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SDLRC - Scientific Articles all years by Author - Gr+


The Sheahan Diamond Literature Reference Compilation
The Sheahan Diamond Literature Reference Compilation is compiled by Patricia Sheahan who publishes on a monthly basis a list of new scientific articles related to diamonds as well as media coverage and corporate announcementscalled the Sheahan Diamond Literature Service that is distributed as a free pdf to a list of followers. Pat has kindly agreed to allow her work to be made available as an online digital resource at Kaiser Research Online so that a broader community interested in diamonds and related geology can benefit. The references are for personal use information purposes only; when available a link is provided to an online location where the full article can be accessed or purchased directly. Reproduction of this compilation in part or in whole without permission from the Sheahan Diamond Literature Service is strictly prohibited. Return to Diamond Resource Center
Sheahan Diamond Literature Reference Compilation - Scientific Articles by Author for all years
A-An Ao+ B-Bd Be-Bk Bl-Bq Br+ C-Cg Ch-Ck Cl+ D-Dd De-Dn Do+ E F-Fn Fo+ G-Gh Gi-Gq Gr+ H-Hd He-Hn Ho+ I J K-Kg Kh-Kn Ko-Kq Kr+ L-Lh
Li+ M-Maq Mar-Mc Md-Mn Mo+ N O P-Pd Pe-Pn Po+ Q R-Rh Ri-Rn Ro+ S-Sd Se-Sh Si-Sm Sn-Ss St+ T-Th Ti+ U V W-Wg Wh+ X Y Z
Sheahan Diamond Literature Reference Compilation - Media/Corporate References by Name for all years
A B C D-Diam Diamonds Diamr+ E F G H I J K L M N O P Q R S T U V W X Y Z
Tips for Users
Posted/Published Reference CodesThe SDLRC provides 3 types of references identified in the reference code. DS for scientific article, DM for a media article, and DC for a corporate announcement. Consider DS0512-0001. The DS stands for "diamond scientific". 05 stands for 2005, the year the reference was posted. 12 represents the month the reference was posted. For all years prior to 2015 the default month is 12. -0001 is the reference's identifier and it does not mean anything. The number below the refence code, ie 2015, is the year the article was published. Note that the posted year may sometimes be later than the published year.
Sort OrderReferences are sorted by the "author" name and when the reference was posted to the compilation.
Most RecentIf the reference code is highlighted yellow, the reference was made available through the most recent monthly compilation of new literature. Use this to check out new references. When new references are posted, we make it our priority to track down an online link and obtain an abstract. With regard to older references, tracking down an abstract and an online link is a work in progress.
Link to external location of article: If the title has a link, it means we have found a location online where you can either retrieve the full article free, or purchase access to it. The Sheahan Diamond Literature Service is not a technical article procurement service; if you want a restricted article, you must deal directly with the vendor who controls the copyright to the article.
Searching this page for a specific term or authorIn your Firefox browser click Edit in the menu bar and then Find. In the Find box that shows up at the bottom of the web page enter your search term. Firefox will highlight all occurrences. This is particularly helpful when the author you are seeking was not the lead author by whom the compilation is sorted.
Sending or sharing a referenceThe left column (Posted/Published) has an embedded hyperlink for each reference. In Firefox, if you right click on it, you can obtain the link url for that reference's location within the page, which you can copy and paste into an email or any other document. You can also use the "share this link" option to tweet, facebook etc the link.
Author Index
A-An Ao+ B-Bd Be-Bk Bl-Bq Br+ C-Cg Ch-Ck Cl+ D-Dd De-Dn Do+ E F-Fn Fo+ G-Gh Gi-Gq Gr+ H-Hd He-Hn Ho+ I J K-Kg Kh-Kn Ko-Kq Kr+ L-Lh
Li+ M-Maq Mar-Mc Md-Mn Mo+ N O P-Pd Pe-Pn Po+ Q R-Rh Ri-Rn Ro+ S-Sd Se-Sh Si-Sm Sn-Ss St+ T-Th Ti+ U V W-Wg Wh+ X Y Z
Sheahan Diamond Literature Reference Compilation - Scientific Articles by Author for all years - Gr+
Posted/
Published
AuthorTitleSourceRegionKeywords
DS2002-0906
2002
GraafsmaKunz, M., Gillet, Fiquet, Sautter, Graafsma, ConradCombined in situ x-ray diffraction and raman spectroscopy on majoritic garnet inclusions in diamondsEarth and Planetary Science Letters, Vol.198,3-4,pp.485-93., Vol.198,3-4,pp.485-93.GlobalSpectroscopy, Diamond inclusions
DS2002-0907
2002
GraafsmaKunz, M., Gillet, Fiquet, Sautter, Graafsma, ConradCombined in situ x-ray diffraction and raman spectroscopy on majoritic garnet inclusions in diamondsEarth and Planetary Science Letters, Vol.198,3-4,pp.485-93., Vol.198,3-4,pp.485-93.GlobalSpectroscopy, Diamond inclusions
DS202009-1674
2020
Grababarczyk, A.Wiszniewska, J.B., Krzeminska, E., Petecki, Z., Grababarczyk, A., Demaiffe, D.Geophysical and petrological constraints for ultramafic-alkaline-carbonatite magmatism in the Tajno intrusion, NE Poland.Goldschmidt 2020, 1p. AbstractEurope, Polandcarbonatites

Abstract: This Tajno alkaline massif (together with the nearby E?k and Pisz intrusions) occurs beneath a thick Mesozoic- Cenozoic sedimentary cover. It has first been recognized by geophysical (magnetic and gravity) investigations, then directly by deep drilling (12 boreholes down to 1800 m). The main rock types identified as clinopyroxenites, syenites, carbonatites, have been cut by later multiphase volcanic /subvolcanic dykes. This massif was characterized as a differentiated ultramafic, alkaline and carbonatite complex, quite comparable to the numerous massifs of the Late Devonian Kola Province of NW Russia [1,2]. Recent geochronological data (U-Pb on zircon from an albitite and Re-Os on pyrrhotite from a carbonatite) indicate that the massif was emplaced at ca. 348 Ma (Early Carboniferous). All the rocks, but more specifically the carbonatites, are enriched in Sr, Ba and LREE, like many carbonatites worldwide but depleted in high field strength elements (Ti, Nb, Ta, Zr). The initial 87Sr/86Sr (0.70370 to 0.70380) and ?Nd(t) (+3.3 to +0.7) isotopic compositions of carbonatites plot in the depleted quadrant of the Nd-Sr diagram, close to “FOcal ZOne” (FOZO) deep mantle domain [1]. The Pb isotopic data (206Pb/204Pb <18.50) do not point to an HIMU (high U/Pb) source. The ranges of C and O stable isotopic compositions of the carbonatites are quite large; some data plot in (or close to) the “Primary Igneous Carbonatite” box while others extend to much higher, typically crustal ?18O and ?13C values.
DS202203-0349
2022
Grabarczyk, A.Grabarczyk, A., Gil, G., Liu, Y., Kotowski, J., Jokubauskas, P., Barnes, J.D., Nejbert, K., Wisniewska, J., Baginski, B.Ultramafic-alkaline-carbonatite Tajno intrusion in NE Poland: a new hypothesis.Ore Geology Reviews, doi.org/10.1016/j.oregeorev.2022.104772 Europe, Polandcarbonatite

Abstract: This manuscript presents results of the newest petrographic, mineralogical and bulk chemical, as well as H, C and O stable isotope study of carbonatites and associated silicate rocks from the Tajno Massif (NE Poland). The Tajno Intrusion is a Tournaisian-Visean ultramafic-alkaline-carbonatite body emplaced within the Paleoproterozoic rocks of the East European Craton (EEC). Carbonatites of the Tajno Massif can be subdivided into the calciocarbonatite (calcite), ferrocarbonatite (ankerite), and breccias with an ankerite-fluorite matrix. Due to location at the cratonic margin and abundance in the REE, Tajno classifies (Hou et al., 2015) as the carbonatite-associated REE deposit (CARD), and more precisely as the Dalucao-Style orebody (the breccia-hosted orebody). High Fe2O3 (13.8 wt%), MnO (2.1 wt%), total REE (6582 ppm), Sr (43895 ppm), Ba (6426 ppm), F (greater than10000 ppm) and CO2 contents points for the involvement of the slab - including pelagic metalliferous sediments - in the carbonatites formation. Spatial relations and Sr isotope composition ((87Sr/86Sr)i = 0.7043-0.7048; Wiszniewska et al., 2020) of alkali clinopyroxenite and syenite suggest that these are products of differentiation of the magma, generated by the initial melting of the SCLM due to influx of F-rich fluids from subducted marine sediments. Carbonatites Sr isotope composition ((87Sr/86Sr)i = 0.7037-0.7038), and Ba/Th (16-20620) and Nb/Y (0.01-6.25) ratios, link their origin with a more advanced melting of the SCLM, triggered by CO2-rich fluids from the subducted AOC and melts from sediments. The Tajno Massif - and coeval mafic-alkaline intrusions - age, high potassic composition, and location along the craton margin nearly parallel the Variscan deformation front, are suggesting Variscan subduction beneath the EEC. The oxygen isotope compositions of clinopyroxene (?18O value = 5.2‰) and alkali feldspar (?18O value = 5.7‰), from alkali clinopyroxenite and foid syenite, respectively, are consistent with mantle-derived magmas. Isotopic compositions of carbonatites and breccias (carbonate ?18O = 8.7‰ to 10.7‰; ?13C = -4.8‰ to ?0.4‰) span from values of primary carbonatites to carbonatites affected by a fractionation or sedimentary contamination. The highest values (?18O = 10.7‰; ?13C = -0.4‰) were reported for breccia cut by numerous veins confirming post-magmatic hydrothermal alteration. The lowest carbonate ?18O (9.3‰ to 10.7‰) and ?13C (?5.0‰ to ?3.8‰) values are reported for veins in alkali clinopyroxenites, whereas the highest ?18O (11.2‰) and ?13C (?1.2‰ to ?1.1‰) values are for veins in syenites and trachytes. Isotopic composition of veins suggests hydrothermal origin, and interaction with host mantle-derived rocks, as well as country rocks. In silicate rocks of the Tajno Massif, fluid influx leads to the development of Pb, Zn, Cu, Ag, Au sulfide mineralization-bearing stockwork vein system, with carbonate, silicate and fluorite infilling the veins. Bulk-rock contents of molybdenum (925 ppm), rhenium (905 ppb) and palladium (29 ppb) are notable. The Re-rich molybdenite association with galena, pyrite and Th-rich bastnäsite in carbonate veins is similar as in Mo deposits associated with carbonatites, implying the mantle source of Mo and Re.
DS2002-0890
2002
Grabezhev, A.I.Korobeinikov, A.F., Grabezhev, A.I., Moloshag, V.P.The behaviour of Pt, Pd and au during the formation of porphyry gold copper systems: evidence from ...Doklady, Vol.383A.March-April pp. 314-7.RussiaGold, copper, platinum, palladium, Deposit - Tominsk Michurinsk
DS1982-0224
1982
Grabkin, O.V.Grabkin, O.V., Zamareyev, S.M., Melnikov, A.I.The Correlation of Endogene Processes of the Siberian Platform and its Framework.Izd. Nauka Sib. Otd. Novosibirsk, Sssr., 129P.Russia, SiberiaKimberlite, Zoning, Diamonds, Genesis
DS2001-0401
2001
Grabowska, T.Grabowska, T., Bojdys, G.The border of the East European Craton in south Eastern Poland based on gravity and magnetic data.Terra Nova, Vol. 13, pp. 92-98.Poland, EuropeGeophysics - gravity, Craton
DS2001-0402
2001
Grabowski, G.Grabowski, G.Diamond potential of lamprophyre in the Lake Temiskaming structural zoneOntario Geological Survey, Northeastern Mineral Symposium, p. 6-8, abstract.OntarioDike - petrology
DS2003-0048
2003
Grabowski, G.Atkinson, B.T., Wilson, A.C., Grabowski, G.An overview of Ontario diamond exploration 2003Quebec Exploration Conference, Nov. 25-27, 1p. abstractOntarioOverview - De Beers, Sudbury Contact, Pele Mountain
DS200412-0070
2003
Grabowski, G.Atkinson, B.T., Wilson, A.C., Grabowski, G.An overview of Ontario diamond exploration 2003.Quebec Exploration Conference, Nov. 25-27, 1p. abstractCanada, OntarioOverview - De Beers, Sudbury Contact, Pele Mountain
DS2002-1560
2002
Grabowski, G.P.B.Stott, G.M., Ayer, J.A., Wilson, A.C., Grabowski, G.P.B.Are the Neoarchean diamond bearing breccias in the Wawa area related to late orogenic alkalic and sunkitoid intrusions?Ontario Geological Survey Open File, Summary of Field Work, No. 6100, pp. 9-1-10.Ontario, WawaDykes, lamprophyres
DS200512-0359
2005
Grabowski, G.P.B.Grabowski, G.P.B., Wilson, A.C.Sampling lamprophere dikes for diamonds: discover Abitibi initiative.Ontario Geological Survey, Open file 6170, 262p. $ 21.00Canada, OntarioGeochemistry - lamprophyres
DS200612-0485
2005
Grabowski, G.P.B.Grabowski, G.P.B., Wilson, A.C.Sampling lamprophyre dikes for diamonds: Discover Abitibi Initiative Project.Ontario Geological Survey, Open File, 6170, 262p.Canada, OntarioGeochemistry
DS1987-0229
1987
Grace, J.D.Fults, M.E., Grace, J.D.Trace element geochemistry of the Lake Ellen kimberlite, Crystal Falls, MichiganGeological Society of America, Vol. 19, No. 4, March p. 199 (abstract)MichiganUSA, Geochemistry
DS1990-0591
1990
Grace, K.Grace, K., Spooner, J.The economics of the rare earth elementsThe Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Annual Meeting Paper preprint, No. 8, 15pGlobalEconomics, Rare earths-excellent overview
DS1997-0434
1997
Grace, K.Grace, K.Mineral reporting practices in Canada vs elsewhereDeveloping Indonesia-Canada Cooperation Nov.3-4, Jakarta, 15p. PEO 13p. Nat Policy 2A 5pCanadaLegal - mining laws, policy, Mineral agreement, investment, contracts, economics
DS1989-0531
1989
Grace, K.A.Grace, K.A.Tax incentives are key to survival of Canadian mineral explorationMining Engineering, Vol. 41, No. 2, February pp. 92-94. Database # 17676CanadaEconomics, CEIP
DS1992-0597
1992
Grace, K.A.Grace, K.A.Competing for the exploration dollar: why Canada?Pda Digest, Vol. 6, No. 28, Summer p. 5, 6CanadaEconomics, Ore reserves, Exploration dollars
DS1996-0556
1996
Grachev, A.F.Grachev, A.F., et al.Tensor characteristics of neotectonic flexural deformations and of curvature lithospheric basementDoklady Academy of Sciences, Vol. 343A No. 6, June pp. 46-53.Russia, East EuropeanEast European Platform, Tectonics
DS200412-0704
2003
Grachev, A.F.Grachev, A.F.Identification of mantle plumes based on studying the composition of volcanic rocks and their isotopic geochemical characteristiPetrology, Vol. 11, 6, pp. 562-596.MantleGeochemistry - plumes
DS200412-0705
2003
Grachev, A.F.Grachev, A.F.The Arctic rift system and the boundary between the Eurasian and North American lithospheric plates: new insight to plate tectonRussian Journal of Earth Sciences, Vol. 5, 5, Oct. pp. 307-345.Russia, Europe, CanadaTectonics
DS1990-0592
1990
Gracie, A.J.Gracie, A.J., Schwann, P.L.Saskatachewan...brief overview of activities. Diamonds one paragraph ( 25lines) overviewPda Exploration And Development Highlights 1989, p. 39SaskatchewanNews item, Diamond exploration -brie
DS2001-0403
2001
Gracie, A.J.Gracie, A.J., Tourigny, G.Diamonds: Candle Lake, Fort a la Corne, StarSaskatchewan Exploration and Dev. Highlights 2000, pp. 10-14.SaskatchewanNews item, Diamond exploration
DS1995-0670
1995
Grad, M.Grad, M., Tripolsky, A.A.Crustal structure from P and S seismic waves and petrological models of the Ukrainian shield.Tectonophysics, Vol. 250, No. 1/3, Nov. 15, pp. 89-112.UKraineTectonics, Geophysics -seismics
DS200712-0088
2006
Grad, M.Bogdanova, S., Gorbatschev, R., Grad, M., Janik, T., Guterch, A., Kozlovskaya, E., Motuza, G., SkridaiteEUROBRIDGE: new insight into the geodynamic evolution of the East European Craton.Geological Society of London Memoir, No. 32, pp. 599-626.EuropeCraton
DS201501-0012
2014
Grad, M.Grad, M., Tiira, T., Olsson, S., Komminaho, K.Seismic lithosphere asthenosphere boundary beneath the Baltic Shield.GFF, Vol. 136, 4, pp. 581-598.Europe, Finland, Sweden, NorwayGeophysics - seismic

Abstract: The problem of the existence of the asthenosphere for old Precambrian cratons is still discussed. In order to study the seismic lithosphere-asthenosphere boundary (LAB) beneath the Baltic Shield, we used records of nine local earthquakes with magnitudes ranging from 2.7 to 5.9. To model the LAB, original data were corrected for topography and Moho depth using a reference model with a 46-km-thick crust. For two northern events at Spitsbergen and Novaya Zemlya, we observe a low-velocity layer, 60-70-km-thick asthenosphere, and the LAB beneath Barents Sea was found at depth of c. 200 km. Sections for other events show continuous first arrivals of P-waves with no evidence for "shadow zone" in the whole range of registration, which could either be interpreted as the absence of the asthenosphere beneath the central part of the Baltic Shield, or that the LAB in this area occurs deeper (>200 km). The relatively thin low-velocity layer found beneath southern Sweden, 15 km below the Moho, could be interpreted as small-scale lithospheric heterogeneities, rather than asthenosphere. Differentiation of the lower lithosphere velocities beneath the Baltic Shield could be interpreted as regional heterogeneity or as anisotropy of the Baltic Shield lithosphere, with high velocities approximately in the east-west direction, and slow velocities approximately in the south-north direction.
DS200412-0706
2004
Gradstein, F.M.Gradstein, F.M., et al.A geological timescale.Geological Survey of Canada, Miscellaneous Report 18, 1 CD $ 6.50TechnologyPoster - timescale
DS1970-0298
1971
Grady, J.C.Grady, J.C.Deep Main Faults in South IndiaGeological Society INDIA Journal, Vol. 12, No. 1, PP. 56-62.IndiaGeotectonics, Regional Structure
DS1987-0811
1987
Grady, M.M.Wright, I.P., Grady, M.M.Meteorites- diamonds are foreverNature, Vol. 326, No. 6115, April 23, pp. 739-740GlobalMeteorite
DS1996-0557
1996
Grady, M.M.Grady, M.M.Meteorites: their flux with time and impact effectsGeoscientist, Vol. 7, No.1, pp. 8-12GlobalMeteorites
DS1998-1068
1998
Grady, M.M.NcCall, G.J.H., Grady, M.M., Hutchison, R.Meteorites - flux with time, impact effectsGeological Society of London Spec. Pub, No. 140, 272p. $ 115.00GlobalBook - ad, Meteorites
DS1920-0186
1924
Graeber, C.K.Honess, A.P., Graeber, C.K.A New Occurrence of an Igneous Dike in Southwestern Pennsylvania.American Journal of Science, SER. 5, Vol. 7, PP. 313-315.United States, Appalachia, PennsylvaniaDixonville, Indiana County, Related Rocks, Geology
DS1920-0284
1926
Graeber, C.K.Honess, A.P., Graeber, C.K.Petrography of the Mica Peridotite Dike at Dixonville, Pennsylvania #2American Journal of Science, SER. 5, Vol. 12, PP. 484-494.United States, Appalachia, PennsylvaniaPetrography, Related Rocks
DS1920-0285
1926
Graeber, C.K.Honess, A.P., Graeber, C.K.Petrography of the Mica Peridotite Dike at Dixonville, Pennsylvania #1Pennsylvania State Coll. Min. Met. Exploration Bulletin., No. 2, 16P.United States, Appalachia, PennsylvaniaRelated Rocks, Petrography
DS1992-0598
1992
Graebner, J.E.Graebner, J.E., Jin, S., Kammlott, G.W., Herb, J.A., Gardiner, C.F.Large anisotropic thermal conductivity in synthetic diamond filmsNature, Vol. 359, No. 6394, October 1, pp. 401-402GlobalDiamond synthesis, CVD.
DS201502-0058
2015
Graedel, T.E.Graedel, T.E., Nassar, N.T.The criticality of metals: a perspective for geologists.In: Ore deposits of an evolving Earth, Geological Society of London,, Special Publication no. 393, pp. 291-302.GlobalEconomics
DS201504-0226
2015
Graettinger, A.HValentine, G.A., Graettinger, A.H, Macorps, E., Ross, P-S., White, J.D.L., Dohring, E., Sonder, I.Experiments with vertically and laterally migrating subsurface explosions with applications to the geology of phreatomagmatic and hydrothermal explosion craters and diatremes.Bulletin of Volcanology, Vol. 77, 15p.TechnologyDiatremes, kimberlites
DS201504-0227
2014
Graettinger, A.HValentine, G.A., Graettinger, A.H, Sonder, I.Explosion depths for phreatomagmatic eruptions.Geophysical Research Letters, Vol. 41, pp. 3045-51.TechnologyMagmatism - phreatomagmatic
DS1995-2034
1995
Graf, C.Waskett-Myers, M., Graf, C.Geochemical sampling and geological report on southwestern Alberta mineralpermits.Alberta Geological Survey, MIN 19950031AlbertaExploration - assessment, Ecstall Mining Corp.
DS201910-2260
2019
Graf, C.Graf, C., Sandner, T., Woodland, A., Hofer, H., Seitz, H-M., Pearson, G., Kjarsgaard, B.Metasomatism, oxidation state of the mantle beneath the Rae craton, Canada.Goldschmidt2019, 1p. AbstractCanadacraton

Abstract: The Rae craton is an important part of the Canadian Shield and was amalgamated to the Slave craton at ?? 1.9 Ga [1]. Recent geophysical and geochemical data indicate a protracted geodynamic history [1, 2]. Even though the oxidation state of the Earth’s mantle has an important influence of fluid compositions and melting behavior, no data on the oxidation state of the Rae’s mantle are available. The aims of this study were to 1) determine the oxidation state (ƒO2) of the lithosphere beneath the Rae craton, 2) link these results to potential metasomatic overprints and 3) compare the geochemical evolution with the Slave craton. We studied 5 peridotite xenoliths from Pelly Bay (central craton) and 22 peridotites from Somerset Island (craton margin). Pelly Bay peridotites give T < 905°C and depths of ??80- 130 km. Garnets have depleted or “normal” REE patterns, the latter samples recording fO2 values ??0.5 log units higher. The deeper samples are more enriched and oxidised. Peridotites from Somerset Island record T ??825-1190°C, a ?logfO2 ranging from ?? FMQ - FMQ-3.6 from a depth interval of ??100-150 km. Garnets exhibit two REE signatures - sinusoidal and “normal” - indicating an evolutionary sequence of increasing metasomatic re-enrichment and a shift from fluid to melt dominated metasomatism. Compared to the Slave craton, the Rae mantle is more reduced at ??80km but becomes up to 2 log units more oxidised (up to ??FMQ-1) at ??100-130 km. Similar oxidising conditions can be found >140 km in the Slave mantle [3]. Especially under Somerset Island, the lithospheric mantle has contrasting fO2 and metasomatic overprints in the same depth range, which may represent juxtaposed old and rejuvenated domains [2].
DS202103-0422
2021
Graf, C.Woodland, A.B., Graf, C., Sandner, T., Hofer, H.E., Seitz, H-M., Pearson, D.G., Kjarsgaard, B.A.Oxidation state and metasomatism of the lithospheric mantle beneath the Rae craton, Canada: strong gradients reflect craton formation and evolution.Nature Scientific Reports, 10.1038/s41598-021-83261-6 11p. PdfCanada, Northwest Territoriesmetasomatism

Abstract: We present the first oxidation state measurements for the subcontinental lithospheric mantle (SCLM) beneath the Rae craton, northern Canada, one of the largest components of the Canadian shield. In combination with major and trace element compositions for garnet and clinopyroxene, we assess the relationship between oxidation state and metasomatic overprinting. The sample suite comprises peridotite xenoliths from the central part (Pelly Bay) and the craton margin (Somerset Island) providing insights into lateral and vertical variations in lithospheric character. Our suite contains spinel, garnet-spinel and garnet peridotites, with most samples originating from 100 to 140 km depth. Within this narrow depth range we observe strong chemical gradients, including variations in oxygen fugacity (ƒO2) of over 4 log units. Both Pelly Bay and Somerset Island peridotites reveal a change in metasomatic type with depth. Observed geochemical systematics and textural evidence support the notion that Rae SCLM developed through amalgamation of different local domains, establishing chemical gradients from the start. These gradients were subsequently modified by migrating melts that drove further development of different types of metasomatic overprinting and variable oxidation at a range of length scales. This oxidation already apparent at ~?100 km depth could have locally destabilised any pre-existing diamond or graphite.
DS202107-1100
2019
Graf, C.Graf, C., Woodland, A., Hofer, H., Seitz, H-M., Pearson, G., Kjarsgaard, B.Metasomatism and oxidation state of lithospheric mantle beneath the Rae Craton, Canada as revealed by xenoliths from Somerset Island and Pelly Bay. ** Note dateGeophysical Research Abstracts , 1p. PdfCanada, Somerset Island , Nunavutcratons

Abstract: We present the first oxidation state measurements for the subcontinental lithospheric mantle (SCLM) beneath the Rae craton, northern Canada, one of the largest components of the Canadian shield. In combination with major and trace element compositions for garnet and clinopyroxene, we assess the relationship between oxidation state and metasomatic overprinting. The sample suite comprises peridotite xenoliths from the central part (Pelly Bay) and the craton margin (Somerset Island) providing insights into lateral and vertical variations in lithospheric character. Our suite contains spinel, garnet-spinel and garnet peridotites, with most samples originating from 100 to 140 km depth. Within this narrow depth range we observe strong chemical gradients, including variations in oxygen fugacity (ƒO2) of over 4 log units. Both Pelly Bay and Somerset Island peridotites reveal a change in metasomatic type with depth. Observed geochemical systematics and textural evidence support the notion that Rae SCLM developed through amalgamation of different local domains, establishing chemical gradients from the start. These gradients were subsequently modified by migrating melts that drove further development of different types of metasomatic overprinting and variable oxidation at a range of length scales. This oxidation already apparent at ~?100 km depth could have locally destabilised any pre-existing diamond or graphite.
DS1988-0265
1988
Graf, G.Graf, G., Will, G.The influence of graphitization on the diamond synthesisTerra Cognita, Vol. 8, No. 1, Winter 1988 p. 64. Abstract onlyGlobalBlank
DS1984-0206
1984
Graf, J.L.Cullers, R.L., Graf, J.L.Rare Earth Elements in Igneous Rocks of the Continental Crust: Predominantly Basic and Ultrabasic Rocks.Rare Earth Geochemistry Edited By Henderson, P. Elsevier Dev, CHAPTER 7, PP. 237-251.GlobalKimberlite, Lamproite, Rare Earth Elements (ree)
DS1960-1084
1969
Graf, P.R.Bryhni, I., Bolingsberg, H.J., Graf, P.R.Eclogites in Quartzo-feldspathic Gneiss of Nordfiord, West Norway.Norsk Geol. Tidsskr., Vol. 49, PP. 194-225.Norway, ScandinaviaPetrography
DS1983-0260
1983
Graff, L.Graff, L.Graff Offers 70 Carat HeartJewellers Circular Keystone, Vol. 154, No. 10, OCTOBER P. D.West AfricaDiamonds Notable
DS1991-0683
1991
Graff, P.J.Hausel, W.D., Edwards, B.R., Graff, P.J.Geology and mineralization of the Wyoming ProvinceAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Preprint, No. 91-72, 12pWyomingBreif mention -diamonds, Overview geology
DS202008-1422
2020
Graff, T.G.McKensie, L., Kilgore, A.H., Peslier, A.D., Brandon, L.A., Schaffer, R.V., Graff, T.G., Agresti, D.G., O'Reilly, S.Y., Griffin, W.L., Pearson, D.G., Hangi, K., Shaulis, B.J.Metasomatic control of hydrogen contents in the layered cratonic mantle lithosphere sampled by Lac de Gras xenoliths in the central Slave craton, Canada.Geochimica et Cosmochimica Acta, in press available, doi.org/101016 /j.gca.2020.07.013 45p. PdfCanada, Northwest Territoriesdeposit - Lac de Gras

Abstract: Whether hydrogen incorporated in nominally anhydrous mantle minerals plays a role in the strength and longevity of the thick cratonic lithosphere is a matter of debate. In particular, the percolation of hydrogen-bearing melts and fluids could potentially add hydrogen to the mantle lithosphere, weaken its olivines (the dominant mineral in mantle peridotite), and cause delamination of the lithosphere's base. The influence of metasomatism on hydrogen contents of cratonic mantle minerals can be tested in mantle xenoliths from the Slave Craton (Canada) because they show extensive evidence for metasomatism of a layered cratonic mantle. Minerals from mantle xenoliths from the Diavik mine in the Lac de Gras kimberlite area located at the center of the Archean Slave craton were analyzed by FTIR for hydrogen contents. The 18 peridotites, two pyroxenites, one websterite and one wehrlite span an equilibration pressure range from 3.1 to 6.6 GPa and include samples from the shallow (? 145 km), oxidized ultra-depleted layer; the deeper (?145-180 km), reduced less depleted layer; and an ultra-deep (? 180 km) layer near the base of the lithosphere. Olivine, orthopyroxene, clinopyroxene and garnet from peridotites contain 30 - 145, 110 - 225, 105 - 285, 2 - 105 ppm H2O, respectively. Within each deep and ultra-deep layer, correlations of hydrogen contents in minerals and tracers of metasomatism (for example light over heavy rare-earth-element ratio (LREE/HREE), high-field-strength-element (HFSE) content with equilibration pressure) can be explained by a chromatographic process occurring during the percolation of kimberlite-like melts through garnet peridotite. The hydrogen content of peridotite minerals is controlled by the compositions of the evolving melt and of the minerals and by mineral/melt partition coefficients. At the beginning of the process, clinopyroxene scavenges most of the hydrogen and garnet most of the HFSE. As the melt evolves and becomes enriched in hydrogen and LREE, olivine and garnet start to incorporate hydrogen and pyroxenes become enriched in LREE. The hydrogen content of peridotite increases with decreasing depth, overall (e.g., from 75 to 138 ppm H2O in the deep peridotites). Effective viscosity calculated using olivine hydrogen content for the deepest xenoliths near the lithosphere-asthenosphere boundary overlaps with estimates of asthenospheric viscosities. These xenoliths cannot be representative of the overall cratonic root because the lack of viscosity contrast would have caused basal erosion of lithosphere. Instead, metasomatism must be confined in narrow zones channeling kimberlite melts through the lithosphere and from where xenoliths are preferentially sampled. Such localized metasomatism by hydrogen-bearing melts therefore does not necessarily result in delamination of the cratonic root.
DS202011-2047
2020
Graff, T.G.Kilgore, M.L., Peslier, A.H., Brandon, A.D., Schaffer, L.A., Morris, R.V., Graff, T.G., Agresti, D.G., O'Reilly, S.Y., Griffin, W.L., Pearson, D.G., Barry, K.G., Shaulis, J.Metasomatic control of hydrogen contents in the layered cratonic mantle lithosphere sampled by Lac de Gras xenoliths in the central Slave Craton, Canada.Geochimica et Cosmochimica Acta, Vol. 286, pp. 29-83. pdfCanada, Northwest Territoriesxenoliths

Abstract: Whether hydrogen incorporated in nominally anhydrous mantle minerals plays a role in the strength and longevity of the thick cratonic lithosphere is a matter of debate. In particular, the percolation of hydrogen-bearing melts and fluids could potentially add hydrogen to the mantle lithosphere, weaken its olivines (the dominant mineral in mantle peridotite), and cause delamination of the lithosphere's base. The influence of metasomatism on hydrogen contents of cratonic mantle minerals can be tested in mantle xenoliths from the Slave Craton (Canada) because they show extensive evidence for metasomatism of a layered cratonic mantle. Minerals from mantle xenoliths from the Diavik mine in the Lac de Gras kimberlite area located at the center of the Archean Slave craton were analyzed by FTIR for hydrogen contents. The 18 peridotites, two pyroxenites, one websterite and one wehrlite span an equilibration pressure range from 3.1 to 6.6 GPa and include samples from the shallow (?145?km), oxidized ultra-depleted layer; the deeper (?145-180?km), reduced less depleted layer; and an ultra-deep (?180?km) layer near the base of the lithosphere. Olivine, orthopyroxene, clinopyroxene and garnet from peridotites contain 30-145, 110-225, 105-285, 2-105?ppm H2O, respectively. Within each deep and ultra-deep layer, correlations of hydrogen contents in minerals and tracers of metasomatism (for example light over heavy rare-earth-element ratio (LREE/HREE), high-field-strength-element (HFSE) content with equilibration pressure) can be explained by a chromatographic process occurring during the percolation of kimberlite-like melts through garnet peridotite. The hydrogen content of peridotite minerals is controlled by the compositions of the evolving melt and of the minerals and by mineral/melt partition coefficients. At the beginning of the process, clinopyroxene scavenges most of the hydrogen and garnet most of the HFSE. As the melt evolves and becomes enriched in hydrogen and LREE, olivine and garnet start to incorporate hydrogen and pyroxenes become enriched in LREE. The hydrogen content of peridotite increases with decreasing depth, overall (e.g., from 75 to 138?ppm H2O in the deep peridotites). Effective viscosity calculated using olivine hydrogen content for the deepest xenoliths near the lithosphere-asthenosphere boundary overlaps with estimates of asthenospheric viscosities. These xenoliths cannot be representative of the overall cratonic root because the lack of viscosity contrast would have caused basal erosion of lithosphere. Instead, metasomatism must be confined in narrow zones channeling kimberlite melts through the lithosphere and from where xenoliths are preferentially sampled. Such localized metasomatism by hydrogen-bearing melts therefore does not necessarily result in delamination of the cratonic root.
DS200512-0156
2005
Graffe, E.Channer, D., Graffe, E., Vielma, P.Geology, mining and mineral potential of southern Venezuela. Diamonds pp. 19-20. Guaniamo area.SEG Newsletter, No. 62, July, pp. 5,13-23.South America, VenezuelaHistory, geology
DS1992-0875
1992
Graham, A.P.Klein, B.W., Graham, A.P., Peterson, S.D.Mining in 1992: a cautious optimism. (United States)Minerals Today, February pp. 6-11United StatesMining, Economics
DS1994-0648
1994
Graham, C.Graham, C., et al.The nature and scale of stable isotope disequilibrium in the mantle: ion and laser microprobe evidence.Mineralogical Magazine, Vol. 58A, pp. 345-346. AbstractMantleGeochronology
DS1990-0443
1990
Graham, C.M.Elphick, S.C., Graham, C.M.Hydrothermal oxygen diffusion in diopside at 1 KB, 900-1200C, a comparison with O diffusion in forsterite, and constraints on OI disequil. in peridotitenodulesTerra, Abstracts of Experimental mineralogy, petrology and, Vol. 2, December abstracts p. 72GlobalExperimental petrology, Kimberlite -peridotite
DS1995-0237
1995
Graham, C.M.Burgess, S.R., Graham, C.M., Valley, J.W., Harte, B.Oxygen isotope composition of metasomatised mantle peridotite xenoliths -laser fluorination/microprobeProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 83-85.South AfricaGeochronology, Deposit -Jagersfontein
DS2001-0899
2001
Graham, C.M.Peck, W.H., Valley, J.W., Wilde, S.A., Graham, C.M.Oxygen isotope ratios and rare earth elements in 3.3 - 4.4 Ga zircons: ion microprobe evidence high 0 18...Geochimica et Cosmochimica Acta, Vol. 65, No. 22, pp. 4215-29.AustraliaGeochronology, Craton - Yilgarn
DS2001-1236
2001
Graham, C.M.Wilde, S.A., Valley, J.W., Graham, C.M.Evidence from detrital zircon for the existence of continental crust and ocean in the earth 4.4 Gyr ago.Nature, Vol. 409, No. 6817, Jan. 11, p. 175-7.MantleGeochronology
DS1999-0231
1999
Graham, D.Furman, T., Graham, D.Erosion of lithospheric mantle beneath the East African Rift system:geochemical evidence from Kivu volcanicsLithos, Vol. 48, No. 1-4, Sept. pp. 237-62.East Africa, KenyaGeochemistry, Lithosphere
DS201412-0309
2014
Graham, D.Graham, D.Mantle geochemistry: small scale stirrings.Nature Geoscience, Vol. 7, July 20, pp. 556-558.MantleGeodynamics
DS1991-0597
1991
Graham, D.F.Graham, D.F., Grant, D.R.A test of airborne, side looking synthetic -aperture radar in central Newfoundland for geological reconnaissanceCanadian Journal of Earth Sciences, Vol. 28, No. 2, February pp. 257-265NewfoundlandRemote sensing, Overview
DS1993-0566
1993
Graham, D.F.Graham, D.F., Bonhamcaon, G.F.Airborne radiometric dat a - a new tool for reconnaissance geological mapping using a GISPhotogrammetry E.R., Vol. 59, No. 8, August, pp. 1243-1249GlobalGIS, Geophysics -radiometric data
DS1994-0649
1994
Graham, D.F.Graham, D.F.Airborne SAR for surficial geological mappingCanadian Journal of Remote Sensing, Vol. 20, No. 3, pp. 319-323CanadaRemote sensing, Alluvials
DS1996-1541
1996
Graham, D.F.Wilkinson, L., Budkewitsch, P., Graham, D.F., HendersonAlternative methods of base map generation using remote sensing and GIS: a pilot study western Churchill ProvinceGeological Survey of Canada Current Research, No. 1997-C, pp. 81-90.Northwest TerritoriesRemote sensing, GIS
DS1997-0435
1997
Graham, D.F.Graham, D.F., Moretzsohn, J.S.Airborne radar data: utility for geological mapping in tropicalenvironments, Serra Pelada, para BrasilThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 90, No. 1011, June pp. 108-113Brazil, Central African RepublicBanded iron formation, Remote Sensing
DS1994-1047
1994
Graham, D.P.Long, R.E., Matthews, P.A., Graham, D.P.The nature of crustal boundaries: combined interpret.of wide angle and normal incidence seismic dataTectonophysics, Vol. 232, pp. 309-318GlobalGeophysics -seismics, Crustal boundaries
DS1994-1048
1994
Graham, D.P.Long, R.E., Matthews, P.A., Graham, D.P.The nature of crustal boundaries: combined interpret. of wide angle and normal incidence seismic data.Tectonophysics, Vol. 232, pp. 309-318.GlobalGeophysics -seismics, Crustal boundaries
DS1995-0671
1995
Graham, D.W.Graham, D.W.Helium, lead, strontium and neodynmium isotope variations in mafic volcanic rocks East African RiftEos, Vol. 76, No. 46, Nov. 7. p.F686. Abstract.GlobalGeochronology
DS1996-1172
1996
Graham, D.W.Reid, M.R., Graham, D.W.Resolving lithospheric and sub lithospheric contributions to helium isotopevariations...Earth and Planetary Science Letters, Vol. 144-1, 2, Oct pp. 213-222.United StatesGeochronology, Lithosphere
DS200512-0360
2005
Graham, D.W.Graham, D.W.Neon illuminates the mantle.Nature, no. 7021, Jan. 6, p. 25.MantleGeochronology
DS200612-0486
2006
Graham, D.W.Graham, D.W., Blichert Toft, J., Russo, C.J., Rubin, K.H., Albarede, F.Cryptic striations in the upper mantle revealed by hafnium isotopes in southeast Indian Ridge basalts.Nature, Vol. 440, 7081, pp. 199-202.Asia, IndiaGeochronology, tectonics
DS200712-0101
2007
Graham, D.W.Brandon, A.D., Graham, D.W., Waight, T., Gautason, B.188 Os amd 187 Os enrichments and high 3He 4He sources in the Earth's mantle evidence from Iclandic picrites.Geochimica et Cosmochimica Acta, Vol. 71, 18, Sept. pp. 4570-91.Europe, IcelandPicrite
DS200712-0102
2007
Graham, D.W.Brandon, A.D., Graham, D.W., Waight, T., Gautason, B.Os He isotope systematics of Iceland picrites: evidence for a deep origin of the Iceland plume.Plates, Plumes, and Paradigms, 1p. abstract p. A119.Europe, IcelandPicrite
DS200712-1127
2007
Graham, D.W.Waight, T., Brandon, A.D., Graham, D.W., Gautason, B.Isotopic constraints on picritic magmatism, Iceland.Plates, Plumes, and Paradigms, 1p. abstract p. A1078.Europe, IcelandPicrite
DS201412-0310
2014
Graham, D.W.Graham, D.W., Hanan, B.B., Hemond, C., Blichert-Toft, J., Albarede, F.Helium isotopic textures in Earth's upper mantle.Geochemistry, Geophysics, Geosystems: G3, Vol. 15, no. 5, pp. 2048-2074.MantleHelium
DS1989-0103
1989
Graham, E.K.Ben Yan, Graham, E.K., Furlong, K.P.Lateral variations in upper mantle thermal structure inferred from three dimensional seismic inversion modelsGeophysical Research Letters, Vol. 16, No. 5, May pp. 449-452GlobalMantle, Seismics -Geophysics
DS200612-1021
2006
Graham, G.R.Oshust, P.A., Graham, G.R., Carlson, J.A.Comparisons of the geology and proposed underground mining methods of the PAnd a and Koala kimberlites at the Ekati diamond mine.CIM Conference and Exhibition, Vancouver - Creating Value with Values, List of talks CIM Magazine, Feb. p. 78.Canada, Northwest TerritoriesMining - Ekati Panda, Kaola
DS200712-0792
2006
Graham, G.R.Oshust, P.A., Carelson, J.A., Graham, G.R., Nowicki, T.E.Comparisons of the geology and proposed underground mining methods of the PAnd a and Kaola kimberlites at the Ekati diamond mine.34th Yellowknife Geoscience Forum, p. 41-42. abstractCanada, Northwest TerritoriesMining methods
DS1998-0176
1998
Graham, I.Bryan, D., Burgess, J., Graham, I., Ravenscroft, P.The Diavik kimberlites - Lac de Gras, Northwest Territories, Canada.Calgary Mining Forum, Apr. 8-9, p. 40-2. abstractNorthwest TerritoriesGeology, Deposit - Diavik
DS1998-0528
1998
Graham, I.Graham, I., Burgess, bryan, Ravenscroft, Thomas, DoyleThe Diavik kimberlites - Lac de Gras, Northwest Territories, Canada7th International Kimberlite Conference Abstract, pp. 259-61.Northwest TerritoriesHistory, kimberlite, evaluation, Deposit - Diavik
DS201502-0123
2014
Graham, I.White, L., Graham, I., Armstrong, R., Hall, R.Tracing the source of Borneo's Cempaka deposit.American Geophysical Union, December - Fall meeting in San Francisco, abstractAsia, KalimantanDeposit - Cempaka
DS201603-0431
2016
Graham, I.White, L.T., Graham, I., Tanner, D., Hall, R., Armstrong, R.A., Yaxley, G., Barron, L.The provenance of Borneo's enigmatic alluvial diamonds: a case study from Cempaka, SE Kalimantan.Gondwana Research, in press available 22p.Asia, KalimantanAlluvials, diamonds

Abstract: Gem-quality diamonds have been found in several alluvial deposits across central and southern Borneo. Borneo has been a known source of diamonds for centuries, but the location of their primary igneous source remains enigmatic. Many geological models have been proposed to explain their distribution, including: the diamonds were derived from a local diatreme; they were brought to the surface through ophiolite obduction or exhumation of UHP metamorphic rocks; they were transported long distances southward via major Asian river systems; or, they were transported from the Australian continent before Borneo was rifted from its northwestern margin in the Late Jurassic. To assess these models, we conducted a study of the provenance of heavy minerals from Kalimantan's Cempaka alluvial diamond deposit. This involved collecting U Pb isotopic data, fission track and trace element geochemistry of zircon as well as major element geochemical data of spinels and morphological descriptions of zircon and diamond. The results indicate that the Cempaka diamonds were likely derived from at least two sources, one which was relatively local and/or involved little reworking, and the other more distal which records several periods of reworking. The distal diamond source is interpreted to be diamond-bearing pipes that intruded the basement of a block that: (1) rifted from northwest Australia (East Java or SW Borneo) and the diamonds were recycled into its sedimentary cover, or: (2) were emplaced elsewhere (e.g. NW Australia) and transported to a block (e.g. East Java or SW Borneo). Both of these scenarios require the diamonds to be transported with the block when it rifted from NW Australia in the Late Jurassic. The local source could be diamondiferous diatremes associated with eroded Miocene high-K alkaline intrusions north of the Barito Basin, which would indicate that the lithosphere beneath SW Borneo is thick (~ 150 km or greater). The ‘local’ diamonds could also be associated with ophiolitic rocks that are exposed in the nearby Meratus Mountains.
DS201605-0907
2016
Graham, I.Sutherland, L., Graham, I., Yaxley, G., Armstrong, R.Major zircon megacryst suites of the Indo-Pacific lithospheric margin (ZIP) and their petrogenetic and regional implications.Mineralogy and Petrology, Vol. 110, 2, pp. 399-420.IndonesiaMegacrysts

Abstract: Zircon megacrysts (± gem corundum) appear in basalt fields of Indo-Pacific origin over a 12,000 km zone (ZIP) along West Pacific continental margins. Age-dating, trace element, oxygen and hafnium isotope studies on representative zircons (East Australia-Asia) indicate diverse magmatic sources. The U-Pb (249 to 1 Ma) and zircon fission track (ZFT) ages (65 to 1 Ma) suggest thermal annealing during later basalt transport, with?
DS201607-1350
2016
Graham, I.Graham, I., Groat, L., Giuliani, G.Gems: bringing the world together,IGC 35th., Session Mineralogy 1 p. abstractTechnologyMineralogy
DS1994-0650
1994
Graham, I.T.Graham, I.T., Franklin, B.J., Marshall, B.Evidence and timing of remobilization in upper mantle peridotiteGeological Society of Australia Abstract Volume, No. 37, pp. 143.MantlePeridotite
DS200812-0426
2007
Graham, I.T.Graham, I.T., Spencer, L., Yaxley, G., Barron, L.The use of zircon in diamond exploration - a preliminary case study from the Cempaka deposit, SE Kalimantan, Indonesia.Geological Society of Australia Abstracts, No. 86, pp. 32-35.IndonesiaDeposit - Cempaka
DS1860-0661
1890
Graham, J.B.Graham, J.B.The Kimberley Diamond Mines (1890)Century, JULY, P.Africa, South AfricaHistory
DS1990-0593
1990
Graham, R.Graham, R., Buseck, P.R.Cathodluminescence of colored diamonds by transmissionelectronmicroscopyGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Vancouver 90 Program with Abstracts, Held May 16-18, Vol. 15, p. A50. AbstractGlobalDiamond morphology, Cathodluminescence
DS1994-0651
1994
Graham, R.J.Graham, R.J., Buseck, P.R.Cathodluminescence of brown diamonds as observed by transmission electronmicroscopy.Phil. Magazine B., Vol. 70, No. 6, Dec. pp. 1177-1185.GlobalDiamond morphology, Cathodluminescence
DS1910-0558
1918
Graham, R.P.D.Poitevin, E., Graham, R.P.D.Contribution to the Mineralogy of Black Lake Area, QuebecGeological Survey of Canada (GSC) MUSEUM Bulletin., No. 27; ( GEOL. SERIES No. 35) 103P.Canada, QuebecBlank
DS1990-0594
1990
Graham, S.Graham, S.Subsidies: encouraging exploration and wasteCrs Perspectives, No. 32, March pp. 17-22CanadaEconomics, Flow-through
DS1990-0937
1990
Graham, S.Liou, J.G., Maruyama, S., Wang, X., Graham, S.Precambrian blueschist terranes of the worldTectonophysics, Vol. 181, pp. 97-111Alaska, Scandinavia, ChinaTerranes, Blueschist
DS1996-0558
1996
Graham, S.Graham, S.Source regions for Norseman and Lara melnoites, western Australia: trace elements and Rb Sr Sm ND and Re OSGeological Society of Australia 13th. Convention held Feb., No. 41, abstracts p.162.AustraliaGeochronology, Yilgarn Craton, Melnoites
DS1996-0559
1996
Graham, S.Graham, S., Lambert, D.D., Shee, S.R., Hamilton, R., FosterAlkaline ultramafic rocks as probes of lithospheric mantle enrichment events in the eastern Yilgarn craton.Australia Nat. University of Diamond Workshop July 29, 30. abstract, 1p.AustraliaCraton, Alkaline rocks, geochronology
DS1997-0436
1997
Graham, S.Graham, S., Lambert, D.D., Shee, S.R., Hamilton, R.ReOs and SmNd evidence for Archean lithosphere mantle modification byorogenesis, Norseman, Western AustraliaGeological Society of Australia Abstracts, No. 44, p. 35. 1p.Australia, Western AustraliaGeochronology, picroilmentites, melnoite, Diamond exploration
DS1998-0529
1998
Graham, S.Graham, S., Lambert, D.D., Shee, S.R., Smith, HamiltonRe Os and Sm neodymium isotope systematics of alkaline ultramafic rocks, xenoliths and macrocrysts...7th International Kimberlite Conference Abstract, pp. 262-4.AustraliaAlkaline rocks, Yilgarn Craton, Earaheedy Basin area
DS1998-0530
1998
Graham, S.Graham, S., Lambert, D.D., Smith, C.B., Shee, ReevesRhenium- Osmium (Re-Os) isotope systematics of oxide xenocrysts and peridotite xenoliths From the kimberlites - Argyle7th International Kimberlite Conference Abstract, pp. 265-7.AustraliaMantle - lithosphere, lamproite, Deposit - Argyle
DS1999-0261
1999
Graham, S.Graham, S., Lambert, D., Shee, S., Smith, C.B., ReevesRe Os isotopic evidence for Archean lithospheric mantle beneath the Kimberley Block, Western Australia.Geology, Vol. 27, No. 5, May pp. 431-34.AustraliaGeochronology, Deposit - Argyle, Seppelt
DS2002-0606
2002
Graham, S.Graham, S., Lambert, D.D., Shee, S.R., Pearson, N.J.Juvenile lithospheric mantle enrichment and the formation of alkaline ultramafic magmaChemical Geology, Vol. 186, No. 2-4, pp. 215-33.Australia, westernMelnoites, Geochronology
DS2003-0492
2003
Graham, S.Graham, S., Lambert, D.D., Shee, S.R.Geochemical and isotopic evidence of a kimberlite - melnoite - carbonatite genetic link8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, AbstractAustraliaKimberlite petrogenesis, Geochronology, Leonora alkalic province
DS2003-0493
2003
Graham, S.Graham, S., Lambert, D.D., Shee, S.R., Pearson, N.J.Erratum to juvenile lithospheric mantle enrichment and the formation of alkalineChemical Geology, Vol. Sept. 15, p.. 361. Original Vol. 186, pp. 215-233.AustraliaMelnoites, Geochronology
DS200412-0145
2004
Graham, S.Beyer, E.E., Brueckner, H.K., Griffin, W.L.,O'Reilly, S.Y., Graham, S.Archean mantle fragments in Proterozoic crust, Western Gneiss region, Norway.Geology, Vol. 32, 7, July pp. 609-612.Europe, NorwayGarnet peridotites
DS200412-0707
2003
Graham, S.Graham, S., Lambert, D.D., Shee, S.R.Geochemical and isotopic evidence of a kimberlite - melnoite - carbonatite genetic link.8 IKC Program, Session 7, AbstractAustraliaKimberlite petrogenesis Geochronology, Leonora alkalic province
DS200412-0708
2003
Graham, S.Graham, S., Lambert, D.D., Shee, S.R., Pearson, N.J.Erratum to juvenile lithospheric mantle enrichment and the formation of alkaline ultramafic magma sources: Re Os Lu Hf and Sm NdChemical Geology, Vol. Sept. 15, p.. 361. Original Vol. 186, pp. 215-233.AustraliaMelnoites, geochronology
DS200412-0722
2004
Graham, S.Griffin, W.L., Graham, S., O'Reilly, S.Y., Pearson, N.J.Lithosphere evolution beneath the Kaapvaal Craton: Re-Os systematics of sulfides in mantle derived peridotites.Chemical Geology, Vol. 208, 1-4, pp. 89-118.Africa, South Africa, LesothoGeochronology, Finsch, Kimberley, Jagersfontein
DS202106-0929
2021
Graham, S.Choi, E., Fiorentini, M.L., Giuliani, A., Foley, S.F., Maas, R., Graham, S.Petrogenesis of Proterozoic alkaline ultramafic rocks in the Yilgarn Craton, western Australia.Gondwana Research, Vol. 93, pp. 197-217. pdfAustraliacarbonatites

Abstract: The Yilgarn Craton and its northern margin contain a variety of petrogenetically poorly defined small-volume alkaline ultramafic rocks of Proterozoic age. This study documents the petrography, mineral and bulk-rock geochemistry and Nd-Hf-Sr-Pb isotope compositions of a selected suite of these rocks. They comprise ~2.03-2.06 Ga ultramafic lamprophyres (UML) and carbonatites from the Eastern Goldfields Superterrane (EGS), ~0.86 Ga UML from Norseman, and orangeites from the Earaheedy Basin, including samples from Jewill (~1.3 Ga), Bulljah (~1.4 Ga) and Nabberu (~1.8-1.9 Ga). The Proterozoic UML and carbonatites from the EGS and Norseman display very consistent chondritic to superchondritic Nd-Hf isotope compositions and trace-element ratios similar to modern OIBs, which are indicative of a common mantle source across this wide alkaline province. These Nd-Hf isotope compositions overlap with the evolution trends of global kimberlites through time, thus suggesting that this mantle source could be deep and ancient as that proposed for kimberlites. Conversely, the orangeites located in the Earaheedy Basin along the northern margin of the Yilgarn Craton display trace element signatures similar to subduction-related calc-alkaline magmas. Taken together with their highly enriched Sr-Nd-Hf isotope compositions, these characteristics indicate an ancient lithospheric mantle source, which was probably metasomatised by subduction-related fluids. As the ages of the Bulljah and Jewill orangeites overlap with the breakup of the Columbia supercontinent, it is proposed that orangeite magmatism was triggered by changes in plate stress conditions associated with this event. This study provides a comprehensive picture of the genesis of Proterozoic alkaline magmatism in the Yilgarn Craton, highlighting the complex tectono-magmatic evolution of this lithospheric block after its assembly in the Archean.
DS2001-1287
2001
Graham, S.A.Yue, Y., Liou, J.G., Graham, S.A.Tectonic correlation of Beishan and Inner Mongolian orogens and its implications for the palinspastic ...Geological Society of America Memoir, No. 194, pp. 101-16.China, MongoliaTectonics - reconstruction of north China
DS2003-0494
2003
Graham, T.Graham, T.TSX Venture Exchange - Canada's public venture capital marketplacePdac Short Course: Comparison Of Listing Requirements For Emerging Mineral, March 12, 17p. text and slidesCanada, OntarioLegal - exchange
DS1910-0415
1914
Grahame, L.Grahame, L.The Diamond Industry and a Review of its Position and Prospects.Jewellers Circular Keystone, Vol. 69, No. 9, SEPT. 30TH. PP. 59, 61, 63, 65.South AfricaMining Economics
DS1900-0188
1903
Graichen, W.Graichen, W.Ist die Zuruckhaltung Unseres Gross kapitals Bei der Entwicklung der Gibeon Diamant Minen Berechtigt?Deut. Kolon. Zeitung, PP. 228-229.Africa, NamibiaHistory, Politics
DS1900-0189
1903
Graichen, W.Graichen, W.Die Newlands Diamantinen SuedafrikaZeitschr. F. Prakt. Geol., Vol. 11, PP. 448-452. ALSO: GEOL. CENTRALL BL., Vol. 6, P. 4South Africa, Griqualand WestGeology, Newland Mine, Kimberlite
DS2002-0607
2002
Grainger, C.J.Grainger, C.J., Groves, D.I., Costa, C.H.G.The epigenetic sediment hosted Serra Pelada au PGE deposit and its potential genetic association ....Society of Economic Geologists Special Publication, No.9,pp.47-64.Brazil, Amazon CratonGold, platinum, iron oxide copper mineralization, Deposit - Serra Pelada, Carajas
DS1982-0225
1982
Grainger, E.Grainger, E.The Remarkable Reverend Clarke; the Life and Times of the Father of Australian Geology.Melbourne: Oxford University Press, 292P.AustraliaKimberley, History, Biography
DS201802-0237
2017
Grakhanov, O.S.Garanin, K.V., Serov, I.V., Nikiforova, A.Yu., Grakhanov, O.S.The ALROSA geological prospecting complex and the analysis of the base for the diamond mining in Russian Federation to 2030. *** IN RUSStarosin, V.I. (ed) Problems of the mineralogy, economic geology and mineral resources. MAKS Press, Moscow *** IN RUS, pp. 22-40.Russiatechnology
DS2003-0495
2003
Grakhanov, S.A.Grakhanov, S.A., Koptil, V.I.Triassic diamond placers on the northeastern Siberian PlatformRussian Geology and Geophysics, Vol. 44, No. 11, pp. 1150-1161Northwestern Siberian Platformplacer deposits
DS200512-0361
2003
Grakhanov, S.A.Grakhanov, S.A., Koptil, V.I.Triassic diamond placers on the northeastern Siberian platform.Russian Geology and Geophysics, Vol. 44, 11, pp. 1150-1161.Russia, SiberiaAlluvials
DS200612-0487
2005
Grakhanov, S.A.Grakhanov, S.A.New dat a on the distribution of diamonds with lonsdaleite admixture in the northeastern Siberian Craton.Doklady Earth Sciences, Vol. 405A, 9, Nov-Dec. pp. 1309-1312.RussiaDiamond mineralogy
DS200812-0427
2007
Grakhanov, S.A.Grakhanov, S.A., Yadrenkin, A.V.Prediction of the diamond potential of Triassic rocks in Taimyr.Doklady Earth Sciences, Vol. 417, 8, pp. 1147-1150.RussiaDiamond genesis
DS201012-0247
2010
Grakhanov, S.A.Grakhanov, S.A., Malanin, Yu.A., Pavlov, Afanasev, Pokhilenko, Gerasimchuk, LipashovaRhaetian diamond placers in Siberia.Russian Geology and Geophysics, Vol. 51, pp. 127-135.Russia, Yakutia, SakhaAlluvials
DS201602-0206
2016
Grakhanov, S.A.Grakhanov, S.A., Zinchuk, N.N., Sobolev, N.V.The age of predictable primary diamond sources in the northeastern Siberian platform.Doklady Earth Sciences, Vol. 465, 2, pp. 1297-1301.Russia, SiberiaDeposit - Malokuonapskaya

Abstract: The U-Pb (SHRIMP) age was determined for zircons collected from 26 observation and sampling sites of diamonds and index minerals in the northeastern Siberian Platform. This part of the region hosts 15 low-diamondiferous Paleozoic and Mesozoic kimberlite fields, excluding the near economic Triassic Malokuonapskaya pipe in the Kuranakh field. Four epochs of kimberlite formation (Silurian, Late Devonian to Early Carboniferous, Middle to Late Triassic, and Middle to Late Jurassic) of the Siberian Platform, including its northeastern part, are confirmed as a result of our studies. Most observation points, including economic Quaternary diamond placers, contain Middle to Late Triassic zircons, which confirms the abundant Late Triassic volcanism in this region. The positive correlation of diamonds and major index minerals of kimberlites (mostly, garnets) at some observation sites indicates the possible Triassic age of the predictable diamondiferous kimberlites.
DS202110-1634
2021
Grakhanov, S.A.Proskumin, V.F., Grakhanov, S.A., Petrov, O.V., Vasiliev, E.A., Berzon, E.I., Antonov, A.V., Sobolev, N.V.Forecast of the diamond potential of Taimyr.Doklady Earth Sciences, Vol. 499, 2, pp. 611-615.Russiadeposit - Taimyr

Abstract: Although irrefutable evidence for the presence of signs of diamondiferous kimberlite on the Taimyr Peninsula were obtained in the 1930s, it was only in 2020 that a macrodiamond (>1 mm) was first discovered in Eastern Taimyr. This was a colorless laminar crystal of a transitional shape from an octahedron to a rhombododecahedron. According to the set of features, the crystal is rare and atypical of the known primary and alluvial deposits of the Siberian Diamond Province. The find of this diamond indicates the presence of primary sources and the need for medium-scale geological survey and exploration over a large area from Anabar Bay (Pronchishchev Ridge) to the west to the Kiryaka-Tas and Tulai-Kiryaka highlands and to the northeast to Tsvetkov Cape.
DS201412-0311
2014
Grakova, O.Grakova, O.Geological characteristics of diamond bearing terrigenous rocks in the north-east borderland of the East European platform.ima2014.co.za, PosterRussiaGeology
DS1991-0598
1991
Gramaccioli, C.M.Gramaccioli, C.M.Application of mineralogical techniques to GemologyEuropean Journal of Mineralogy, Vol. 3, No. 4, pp. 703-706GlobalGemology -general, Brief overview
DS1989-0532
1989
Grambling, J.A.Grambling, J.A., Tewksbury, B.J.Proterozoic geology of the Southern Rocky MountainsGeological Society of America (GSA) Special Paper, No. 235, 176p. $ 27.50Wyoming, Colorado, Utah, New mexico, ArizonaGeochronology, Tectonics
DS1997-0571
1997
Grambling, J.A.Karlstrom, K.E, Dallmeyer, R.D., Grambling, J.A.Ar-Ar evidence for 1.4 Ga regional metamorphism in New Mexico: Implications for thermal evolution of lithosph.Journal of Geology, Vol. 105, No. 2, March pp.205-223.United States, New MexicoThermal evolution, Argon, Lithosphere
DS200812-0786
2008
GramboleNasdala, L., Gigler, Wildner, Grambole, Zaitsev, Harris, Hofmeister, Milledge, SatitkuneAlpha radiation damage in diamond.Goldschmidt Conference 2008, Abstract p.A672.TechnologyDiamond morphology
DS201312-0637
2013
Grambole, D.Nasdala, L., Grambole, D., Wildner, M., Gigler, A.M., Hainschwang, T., Zaitsev, A.M., Harris, J.W., Milledge, J., Schulze, D.J., Hofmeister, W., Balmer, W.A.Radio-colouration of diamond: a spectroscopic study.Contributions to Mineralogy and Petrology, Vol. 165, pp. 843-861.Africa, South Africa, Democratic Republic of Congo, South America, Brazil, VenezuelaDiamond - colour
DS1985-0243
1985
GramenitskiiGramenitskiiReflectance of Diamonds Containing Varying Contents of Lonsdaleite.(russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 279, pp. 186-188RussiaRef. Fleischer United States Geological Survey (usgs) Of 88-689.mineralogical Refs. 198
DS200612-0488
2006
Gramling, C.Gramling, C.Ultraslow ridges hold new clues to crust's formation.Science News , Vol. 169, 13, April 1, 8p.Asia, Indian Ocean RidgeTectonics, layer cake
DS200712-0378
2007
Gramling, C.Gramling, C.X-Ray eyes in the sky: scientists are working on satellites that will see far below the planet's surface, better understand structure and compositionGeotimes, Vol. 52, 7, pp. 24-27.MantleCrust, mantle, core
DS202005-0734
2020
Gramling, C.Gramling, C.Plate tectonics may have started 400 million years earlier than we thought. sciencemag.org, April 22, 3p.AustraliaTectonics

Abstract: Modern plate tectonics may have gotten under way as early as 3.2 billion years ago, about 400 million years earlier than scientists thought. That, in turn, suggests that the movement of large pieces of Earth’s crust could have played a role in making the planet more hospitable to life. Geologist Alec Brenner of Harvard University and his colleagues measured the magnetic orientations of iron-bearing minerals in the Honeyeater Basalt, a layer of rock that formed between 3.19 billion and 3.18 billion years ago. The basalt is part of the East Pilbara Craton, an ancient bit of continent in Western Australia that includes rocks as old as 3.5 billion years. This craton, the researchers found, was on the move between 3.35 billion and 3.18 billion years ago, drifting around the planet at a rate of at least 2.5 centimeters per year. That’s a speed comparable to modern plate motions, the team reports April 22 in Science Advances.
DS1996-0560
1996
Grana, J.P.Grana, J.P., Richardson, R.R.Tectonic stress within the New Madrid seismic zoneJournal of Geophysical Research, Vol. 101, No. B3, March 10, pp. 5445-58.MidcontinentTectonics, Geophysics -seismics
DS201502-0053
2010
Granado, P.deVera, J., Granado, P., McClay, K.Structural evolution of the Orange Basin gravity-driven system, offshore Namibia.Marine and Petroleum Geology, Vol. 27, 1, pp. 223-237.Africa, NamibiaStructure
DS1988-0043
1988
Granain, V.K.Barsanov, G.P., Granain, V.K., Kuznetsov, V.P.Diamond in diamond inclusions from kimberlitic pipes of Yakutia. (Russian)Geologii i Geofiziki, (Russian), No. 3, March pp. 132-137RussiaBlank
DS1984-0746
1984
Granata, J.S.Tyson, R., Theisen, A.F., Granata, J.S., Hemphill, W.R.Detection of Visible Luminescence from a Rare Earth Elements (ree) Bearing Carbonatite in Southern California.Geological Society of America (GSA), Vol. 16, No. 4, P. 258. (abstract.)California, West CoastRelated Rocks
DS2002-0608
2002
Grancea, L.Grancea, L., Bailly, L., Leroy, Banks, Marcoux, MilisiFluid evolution in the Baia Mare epithermal gold/polymetallic district, Inner CarpathiansMineralium deposita, RomaniaGold, copper, zinc, Deposit - Baia Mare
DS200912-0042
2009
GrandBegg, G.C., Griffin, W.L., Natapov, O'Reilly, Grand, O'Neill, Hronsky, Poudjom Djomeni, Swain, Deen, BowdenThe lithospheric architecture of Africa: seismic tomography, mantle petrology, and tectonic evolution.Geosphere, Vol. 5, pp. 23-50.AfricaGeophysics - seismic, tectonics
DS1994-1283
1994
Grand, P.Nolet, G., Grand, P., Kennett, B.L.N.Seismic heterogeneity in the upper mantleJournal of Geophysical Research, Vol. 99, No. B 12, Dec. 10, pp. 23, 753-66.MantleGeophysics -seismics
DS200412-2101
2004
Grand, S.West, M., Ni, J., Baldridge, W.S., Wilson, D., Aster, R., Gao, W., Grand, S.Crust and upper mantle shear wave structure of the southwest United States: implications for rifting and support for high elevatJournal of Geophysical Research, Vol. 109, 3, DOI 10.1029/2003 JB002575United States, California, Colorado PlateauGeophysics - seismics, tectonics
DS200512-1185
2005
Grand, S.Wilson, D., Aster, R., Ni, J., Grand, S., West, M., Gao, W.,Baldridge, W.S., Semken, S.Imaging the seismic structure of the crust and upper mantle beneath the Great Plains, Rio Grande Rift, and Colorado Plateau using receiver functions.Journal of Geophysical Research, Vol. 110, B5, 10.1029/2004 JB003492United States, Colorado PlateauGeophysics - seismics
DS200512-1186
2005
Grand, S.Wilson, D., Aster, R., Ni, J., Grand, S., West, M., Gao, W., Baldridge, W.S., Semken, S.Imaging the seismic structure of the crust and upper mantle beneath the Great Plains, Rio Grande Rift and Colorado Plateau using receiver functions.Journal of Geophysical Research, Vol. 110, B5 May 28, B05306 10.1029/2004 JB003492United States, ColoradoGeophysics - seismics
DS1987-0254
1987
Grand, S.P.Grand, S.P.Tomographic inversion for shear velocity beneath the North American plateJournal of Geophysical Research, Vol. 92, pp. 14065-90.Quebec, Ontario, manitoba, AlbertaTomography, Tectonics
DS1990-0495
1990
Grand, S.P.Frohlich, C., Grand, S.P.The fate of subducting slabsNature, Vol. 347, No. 6291, September 27, pp. 333-334GlobalTectonics, Subducting slabs
DS1991-1528
1991
Grand, S.P.Schwartz, S.Y., Lay, T., Grand, S.P.Seismic imaging of subducted slabs: trade offs with deep path and near receiver effectsGeophysical Research Letters, Vol. 18, No. 7, July pp. 1265-1268GlobalMantle, Tectonis, subduction, geophysics, seismics
DS1994-0652
1994
Grand, S.P.Grand, S.P.Mantle shear structure beneath the Americas and surrounding oceansJournal of Geophy. Res, Vol. 99, No. B6, June 10, pp. 11, 591-11, 621MantleGeophysics -seismics, Tectonics, structure
DS1994-0653
1994
Grand, S.P.Grand, S.P.Mantle shear structure beneath the Americas and surrounding oceansJournal of Geophysical Research, Vol. 99, No. B6, June 10, pp. 11, 591-11, 621.United StatesMantle, Core mantle boundary
DS1996-0829
1996
Grand, S.P.Lee, D-K., Grand, S.P.Upper mantle shear structure beneath the Colorado Rocky MountainsJournal of Geophysical Research, Vol. 101, No. B10, Oct. 10, pp. 22, 233-44.Colorado, WyomingTectonics, Structure
DS1997-0437
1997
Grand, S.P.Grand, S.P., Van der Hilst, R.D., Widiyantoro, S.Global seismic tomography: a snapshot of convection in the earthGsa Today, Vol. 7, No. 4, April pp. 1-7.GlobalTomography, Geophysics - seismics
DS2002-0609
2002
Grand, S.P.Grand, S.P.Mantle shear wave tomography and the fate of subducted slabsPhilosophical Transactions, Royal Society of London Series A Mathematical, Vol.1800, pp. 2475-92.MantleSubduction
DS2002-1489
2002
Grand, S.P.Simmons, N.A., Grand, S.P.Partial melting in the deepest mantleGeophysical Research Letters, Vol. 29, 10, DOI 10.1029/2001GL013716MantleMelting
DS200412-0607
2004
Grand, S.P.Gao, W., Grand, S.P., Baldridge, W.S., Wilson, D., West, M., Ni, J.F., Aster, R.Upper mantle convection beneath the central Rio Grande rift imaged by P and S wave tomography.Journal of Geophysical Research, Vol. 109, 3, DOI 10.1029/2003 JB002743United States, New Mexico, Colorado PlateauGeophysics - seismics, tectonics
DS200412-1988
2004
Grand, S.P.Thorne, M.S., Garnero, E.J., Grand, S.P.Geographic correlation between hot spots and deep mantle lateral shear wave velocity gradients.Physics of the Earth and Planetary Interiors, Vol. 146, 1-2, pp. 47-63.MantleGeophysics - seismics, plumes
DS200612-1307
2006
Grand, S.P.Simmons, N.A., Forte, A.M., Grand, S.P.Constraining mantle flow with seismic and geodynamic data: a joint approach.Earth and Planetary Science Letters, Vol. 246, 1-2, June 15, pp. 109-124.MantleGeophysics - seismics
DS200812-0770
2008
Grand, S.P.Moucha, R., Forte, A.M., Mitrovica, J.X., Rowley, D.B., Quere, S., Simmons, Grand, S.P.Dynamic topography and long term sea level variations: there is no such thing as a stable continental platform.Earth and Planetary Science Letters, Vol. 271, 1-4, pp. 101-108.MantleGeomorphology
DS200812-0771
2008
Grand, S.P.Moucha, R., Forte, A.M., Mitrovica, J.X., Rowley, D.B., Quere, S., Simmons, N.A., Grand, S.P.Dynamic topography and long term sea level variations: there is no such thing as a stable continental platform.Earth and Planetary Science Letters, Vol. 271, 1-4, pp. 101-108.MantleCraton
DS200812-0772
2008
Grand, S.P.Moucha, R., Forte, A.M., Rowley, D.B., Mitrovica, J.X., Simmons, N.A., Grand, S.P.Mantle convection and the recent evolution of the Colorado Plateau and the Rio Grande Rift valley.Geology, Vol. 36, 6, pp. 439-442.United States, Colorado PlateauConvection
DS200812-1072
2008
Grand, S.P.Sine, C.R., Wilson, D., Gao, W., Grand, S.P., Aster, R., Ni, J., Baldridge, W.S.Mantle structure beneath the western edge of the Colorado Plateau.Geophysical Research Letters, Vol. 35, 10, May 28, L10303.United States, Colorado PlateauTectonics
DS200812-1240
2008
Grand, S.P.Wang, X., Ni, J.F., Aster, R., Sandovi, E., Wilson, D., Sine, C., Grand, S.P., Baldridge, W.S.Shear wave splitting and mantle flow beneath the Colorado Plateau and its boundary with the Great Basin.Bulletin of Seismological Society of America, Vol. 98, 5, pp. 2526-2532.United States, Colorado PlateauGeophysics - seismics
DS201012-0206
2010
Grand, S.P.Forte, A.M., Moucha, R., Simmons, N.A., Grand, S.P., Mitrovica, J.X.Deep mantle contributions to the surface dynamics of the North American continent.Tectonophysics, Vol.481, 1-4, pp. 3-15.Canada, United StatesTectonics
DS201012-0207
2010
Grand, S.P.Forte, A.M., Quere, S., Moucha, R., Simmons, N.A., Grand, S.P., Mitrovica, J.X., Rowley, D.B.Joint seismic geodynamic mineral physical modeling of African geodynamics: a reconciliation of deep mantle convection with surface geophysical constraints.Earth and Planetary Science Letters, Vol. 295, 3-4, pp. 329-341.AfricaGeophysics - seismics
DS201012-0812
2010
Grand, S.P.Van Wijk, J.W., Baldridge, W.S., Van Hunen, J., Goes, S., Aster, R., Coblentz, D.D., Grand, S.P., Ni, J.Small scale convection at the edge of the Colorado Plateau: implications for topography, magmatism, and evolution of Proterozoic lithosphere.Geology, Vol. 38, 7, pp. 611-614.United States, Colorado PlateauMagmatism
DS201212-0086
2011
Grand, S.P.Brandt, M.B., Grand, S.P., Nyblade, A.A., Dirks, P.H.G.Upper mantle seismic structure beneath southern Africa: constraints on the bouyancy supporting the African Superswell.Pure and Applied Geophysics, Vol. 169, 4, pp. 595-614.Africa, South AfricaMantle - geophysics
DS1860-0084
1869
GrandidierGrandidierVoyage dans les Provinces Meridonales de L'indeTour Du Monde., IndiaTravelogue
DS1992-1419
1992
Grandstaff, D.Sirkis, D., Grandstaff, D., Castro, J., Gold, D.Testing a model of diatreme emplacement at Oka, Quebec, using rockmagnetismEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 102QuebecCarbonatite, Oka
DS1998-1496
1998
Grandstaff, D.Ulmer, G.C., Grandstaff, D., Gobbels, M., Woermann, E.An experimental delineation of the oxygen fugacity of moissanite ( SiC)bearing silicate systems.7th International Kimberlite Conference Abstract, pp. 932-33.GlobalMineral chemistry, Moissanite
DS1998-1588
1998
Grandstaff, D.Woermann, E., Gobbels, M., Ulmer, G.C., Grandstaff, D.Moissanite and its bearing on the oxygen fugacity of the deeper regimes Of the Earth's upper mantle.7th International Kimberlite Conference Abstract, pp. 958-9.MantleMoissanite, Peridotite xenoliths
DS1987-0758
1987
Grandstaff, D.E.Ulmer, G.C., Grandstaff, D.E., Weiss, D., Moats, M.A., et al.The mantle redox state: an unfinished story?Mantle metasomatism and alkaline magmatism, edited E. Mullen Morris and, No. 215, pp. 5-24GlobalModel, IOF.
DS1992-0599
1992
Grandstaff, D.E.Grandstaff, D.E., Ulmer, G.C.Fluid inclusions in diamond, equations of state and mantle redoxconditionsEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.335MantleDiamond morphology, Mantle redox
DS1999-0755
1999
Grandstaff, D.E.Ulmer, G.C., Grandstaff, D.E.Redox stability of moissanite (SIC) and diamond fluid inclusions:implications for the mantle.Geological Association of Canada (GAC) Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC)., Vol. 24, p. 132. abstractMantleMoissanite
DS2002-0109
2002
Granet, M.Barruol, G., Granet, M.A Tertiary asthenospheric flow beneath the southern French Massif Central indicated by upper mantle seismic anisotropy and related to west mediterranean extension.Earth and Planetary Science Letters, Vol. 202, 1, pp.31-47.EuropeGeophysics - seismics
DS201909-2029
2019
Granet, M.Chandra, J., Paul, D., Stracke, A., Chabaux, F., Granet, M.The origin of carbonatites from Amba Dongar within the Deccan Large Igneous Province.Journal of Petrology , Vol. 60, 6, pp. 1119--1134.Indiacarbonatite

Abstract: There are disparate views about the origin of global rift- or plume-related carbonatites. The Amba Dongar carbonatite complex, Gujarat, India, which intruded into the basalts of the Deccan Large Igneous Province (LIP), is a typical example. On the basis of new comprehensive major and trace element and Sr-Nd-Pb isotope data, we propose that low-degree primary carbonated melts from off-center of the Deccan-Réunion mantle plume migrate upwards and metasomatize part of the subcontinental lithospheric mantle (SCLM). Low-degree partial melting (?2%) of this metasomatized SCLM source generates a parental carbonated silicate magma, which becomes contaminated with the local Archean basement during its ascent. Calcite globules in a nephelinite from Amba Dongar provide evidence that the carbonatites originated by liquid immiscibility from a parental carbonated silicate magma. Liquid immiscibility at crustal depths produces two chemically distinct, but isotopically similar magmas: the carbonatites (20% by volume) and nephelinites (80% by volume). Owing to their low heat capacity, the carbonatite melts solidified as thin carbonate veins at crustal depths. Secondary melting of these carbonate-rich veins during subsequent rifting generated the carbonatites and ferrocarbonatites now exposed at Amba Dongar. Carbonatites, if formed by liquid immiscibility from carbonated silicate magmas, can inherit a wide range of isotopic signatures that result from crustal contamination of their parental carbonated silicate magmas. In rift or plume-related settings, they can, therefore, display a much larger range of isotope signatures than their original asthenosphere or mantle plume source.
DS200712-0800
2007
Granick, S.Par, G-S., Bae, S.C., Granick, S., Lee, J-H., Bae, S-D, Kim, T., Zuo, J.M.Naturally formed epitaxial diamond crystals in rubies.Diamond and Related Materials, Vol. 16, 2, Feb., pp. 397-400.TechnologyDiamond crystallography, rubies
DS200712-0801
2007
Granick, S.Park, G.S., Bae, S.C., Granick, S., Lee, J.H., Bae, S.D., Kim, T., Zuo, J.M.Naturally formed epitaxial diamond crystals in rubies.Diamond and Related Materials, Vol. 16, 2, pp. 397-400 Ingenta 1070685098TechnologyDiamond morphology
DS200712-0261
2007
GraninDobtresov, V.Y., Psakhe, S.G., Popov, V.L., Shilko, E.V., Granin, Timofeev,Astafurov, Dimaki, StarchevichIce cover of Lake Baikal as a model for studying tectonic processes in the Earth's crust.Doklady Earth Sciences, Vol. 413, 2, pp. 155-159.RussiaGeomorphology
DS1992-0600
1992
Grannik, V.M.Grannik, V.M.Magmatic evolution during rifting and some practical consequencesDoklady Academy of Science USSR, Earth Science Section, Vol. 312, No. 1-3, June pp. 247-249RussiaTectonics -rifting, Magma
DS1995-1161
1995
GranovskyMarakushev, A.A., Mitreikina, O.B., Zinolieva, GranovskyDiamondiferous meteorites and their genesisPetrology, Vol. 3, No. 5, Sept-Oct. pp. 407-423.RussiaMeteorites
DS1990-0289
1990
Granozzi, G.Casarin, M., Granozzi, G., Tondello, E., Vittadin, A.A molecular cluster approach to the electronic structure of anomalous muonium in diamondChem. Phys, Vol. 148, No. 2-3, December 1, pp. 183-192GlobalDiamond morphology, MuoniuM.
DS1990-1301
1990
Grant, A.C.Sanford, B.V., Grant, A.C.New findings relating to the stratigraphy and structure of the HudsonPlatformGeological Survey of Canada Paper, Interior Plains and Arctic Canada, No. 90-1D pp. 17-30Ontario, ManitobaStructure, Hudson Platform
DS1998-1282
1998
Grant, A.C.Sanford, B.V., Card, K.D., Grant, A.C., Okulitch, A.V.Bedrock geology, James Bay Ontario - District of Keewatin, NorthwestTerritories.Geological Survey of Canada Open file, No. 3558, 1:1, 000, 000 $ 26.00Ontario, Northwest TerritoriesMap - bedrock geology, James Bay Lowlands
DS1999-0624
1999
Grant, A.C.Sanford, B.V., Grant, A.C.Paleozoic and Mesozoic geology of the Hudson and southeast Arcticplatforms.Geological Survey Open File, No. 3595, 1: 2, 500, 000 $ 40.00Northwest Territories, Ontario, ManitobaMap
DS1992-0728
1992
Grant, B.Hora, Z.D., Hamilton, W.N., Grant, B., Kelly, P.D.Industrial minerals of Alberta and British Columbia, Canada. Proceedings Of the 27th. Forum on geology of industrial mineralsBritish Columbia Department of Mines, Paper No. 1991-23, 214p. $ 30.00British Columbia, AlbertaIndustrial minerals, Table of contents
DS1994-0654
1994
Grant, B.Grant, B.Diamond origin and transport: kimberlites and lamproitesThe Gangue (MDD Newsletter), No. 46, Sept. pp. 12-14.GlobalDiamond genesis, Overview -brief but concise
DS2001-0404
2001
Grant, B.Grant, B.The art and science of writing geoscience reports. RevisionProspectors and Developers Association of Canada (PDAC), Geological Association of Canada (GAC), Geological Society of Canada (GSC), distributors, GlobalBook - ad, Report writing - revision
DS200512-0668
2005
Grant, B.MacKenzie, J.M., Canil, D., Johnston, S.T., English, J., Mihalynuk, M.G., Grant, B.First evidence for ultrahigh pressure garnet peridotite in the North American Cordillera.Geology, Vol. 33, 2, pp. 105-108.Canada, Yukon, British ColumbiaUHP, Mantle lithosphere
DS200612-0218
2005
Grant, B.Canil, D., Mihalynuk, M., MacKenzie, J.M., Johnston, S.T., Grant, B.Diamond in the Atlin-Nakin a region, British Columbia: insights from heavy minerals in stream sediments.Canadian Journal of Earth Sciences, Vol. 42, 12, Dec. pp. 2161-2171.Canada, British Columbia, Yukon, United States, AlaskaGeochemistry
DS1975-0088
1975
Grant, B.G.Grant, B.G.Exploration of Diamonds Phase IiLesotho Department of Mines And Geology, PROJECT No. LES73/021 SPECIAL REPORT BG/1. AND MAP SHEET 292LesothoBlank
DS1975-0285
1976
Grant, B.G.Grant, B.G.Exploration for Diamonds Phase IiLesotho Department of Mines And Geology, PROJECT LES73/021, SPECIAL REPORT BG/2. FIELD GEOLOGISTS REPLesothoBlank
DS1991-0597
1991
Grant, D.R.Graham, D.F., Grant, D.R.A test of airborne, side looking synthetic -aperture radar in central Newfoundland for geological reconnaissanceCanadian Journal of Earth Sciences, Vol. 28, No. 2, February pp. 257-265NewfoundlandRemote sensing, Overview
DS200412-0709
2004
Grant, I.F.Grant, I.F., Heyraud, C., Breon, F-M.Continentral scale hotspot observations of Australia at sub-degree anular resolution from POLDER.International Journal of Remote Sensing, Vol. 25, 18, Sept. pp. 3625-36.AustraliaGeophysics - remote sensing
DS1994-1825
1994
Grant, J.Van der Hilst, R., Kennettm B., Christie, D., Grant, J.Project Skippy explores the lithosphere and mantle beneath AustraliaEos, Vol. 75, No. 15, April 12, pp. 177, 180, 181AustraliaMantle, Geophysics -seismics
DS200512-0362
2005
Grant, J.Grant, J.Diamonds, foreign aid and the uncertain prospects for post-conflict reconstruction in Sierra Leone.The Round Table, Vol. 94, No. 381, pp. 443-457.Africa, Sierra LeoneHistory
DS200612-0489
2005
Grant, J.Grant, J.Diamonds, foreign aid and the uncertain prospects for post conflict reconstruction in Sierra Leone.The Round Table, Vol. 94, Sept. no. 981, pp. 443-457.Africa, Sierra LeoneConflict diamonds
DS1990-0595
1990
Grant, J.A.Grant, J.A., Frost, B.R.Contact metamorphism and partial melting of pelitic rocks in the Aureole of the Laramie anorthosite complex Morton Pass WyomingAmerican Journal of Science, Vol. 290, No. 4, April pp. 425-WyomingAnorthosite, Geochemistry
DS1991-1260
1991
Grant, J.A.Olsen, S.N., Grant, J.A.Isocon analysis of migmatization in the Front Range, Colorado, USAJournal of Metamorphic Geology, Vol. 9, No. 2, March pp. 151-164ColoradoMignatization, Geochronology
DS1993-0567
1993
Grant, J.A.Grant, J.A.SurView - a microsoft window 3.1 application to view geophysical surveydat a ( line, grid, contour, and stacked profilesGeological Survey of Canada, Open file, No. 2661, 1 discGlobalGeophysics, Computer -program SurView
DS1995-1170
1995
Grant, J.A.Markarian, D., Grant, J.A., Elliott, B.E.LogView - microsoft windows borehole log ProgramGeological Survey of Canada, Open File 3055 $ 100.00GlobalComputer, Program -LogView
DS2001-0405
2001
Grant, J.A.Grant, J.A.SurView - a GIS application Windows - viewing geophys. survey dat a (line, grid, contout and stacked profilesGeological Survey of Canada (GSC) Open File, D2661, 1 CD, $ 100.GlobalComputer, Program - SurView
DS200412-0710
2004
Grant, J.A.Grant, J.A., Taylor, I.Global governance and conflict diamonds: the Kimberley Process and the Quest for clean gems.Round Table, ( CARFAX Publ.) Ingenta 1043486217, No. 375, pp. 385-402.GlobalLegal - Kimberley Process
DS200612-0490
2006
Grant, J.A.Grant, J.A.Isocon analysis: a brief review of the method and applications.Physics and Chemistry of the Earth Parts A,B,C, Vol. 30, 17-18, pp. 997-1004.TechnologyMetasomatism, geochemistry
DS201312-0330
2013
Grant, J.Andrew.Grant, J.Andrew.Commonwealth cousins combating conflict diamonds: an examination of South African and Canadian contributions to the Kimberley Process.Commonwealth and Comparative Politics ( Routledge Pub)., Vol. 51, 2, pp. 1466-2043. IngentaCanada, Africa, South AfricaKimberley Process
DS1993-0701
1993
Grant, J.W.Hrabi, R.B., Grant, J.W., Godin, P.D., Helmstaedt, H., King, J.E.Geology of the Winter Lake supracrustal belt, central Slave Province, District of Mackenzie, N.W.T.Geological Survey Canada Paper, No. 93-1C, pp. 71-82Northwest TerritoriesWinter Lake, Regional geology
DS1994-0787
1994
Grant, J.W.Hrabi, R.B., Grant, J.W., Berclaz, A., Duquette, D., Villeneuve, M.E.Geology of the northern half of the Winter Lake supracrustal belt, SlaveProvince, Northwest Territories.Geological Survey of Canada Current Research, No. 1994, C, pp. 13-22.Northwest TerritoriesGeology, Winter Lake
DS200712-0379
2007
Grant, K.Grant, K., Ingrin, J., Lorand, J.P., Dumas, P.Water partitioning between mantle minerals from peridotite xenoliths.Contributions to Mineralogy and Petrology, Vol. 154, 1, pp. 15-34.MantleMineralogy - hydrous phase
DS200612-0491
2006
Grant, K.J.Grant, K.J., Kohn, S.C., Brooker, R.A.Solubility and partitioning of water in synthetic forsterite and enstatite in the system MgO SiO2 and H2Al2O3.Contributions to Mineralogy and Petrology, Vol. 151, 6, pp. 651-664.TechnologyPetrology
DS200612-0619
2006
Grant, K.J.Ingrin, J., Grant, K.J.H profiles in mantle xenoliths: constraints from diffusion data.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1. abstract only.MantleGeochemistry
DS200712-0380
2007
Grant, K.J.Grant, K.J., Brooker, R.A., Kohn, S.C., Wood, B.J.The effect of oxygen fugacity on hydroxyl concentrations and speciation in olivine: implications for water solubility in the upper mantle.Earth and Planetary Science Letters, Vol. 261, 1-2, pp. 217-229.MantleWater
DS200912-0008
2009
Grant, K.J.Araujo, D.P., Griffin, W.L., O'Reilly, S.Y., Grant, K.J., Ireland, T., Van Achterbergh, E.Micro inclusions in monocrystalline octahedral diamonds and coated diamonds from Diavik, Slave Craton: clues to diamond genesis.Lithos, In press available 38p.Canada, Northwest TerritoriesDeposit - Diavik
DS201212-0310
2012
Grant, K.J.Howell, D., O'Neill, C.J., Grant, K.J., Griffin, W.L., O'Reilly, S.Y., Pearson, N.J., Stern, R.A., Stachel, T.Platelet development in cuboid diamonds: insights from micro-FTIR mapping.Contributions to Mineralogy and Petrology, Vol. 164, 6, pp. 1011-1025.TechnologyDiamond morphology
DS1997-0764
1997
Grant, N.Menzel-Jones, A., Ferguson, I.J., Grant, N., Roberts, B.Deep Slave: probing the deep lithosphere beneath the Slave Craton and adjacent terranes using electromagnetic imaging.Geological Survey of Canada Forum 1997 abstracts, p. 4. AbstractNorthwest TerritoriesCraton, Geophysics - electromagnetic
DS1989-1223
1989
Grant, S.Piper, J.D.A., Grant, S.A paleomagnetic test of the axial dipole assumption and complications for continental distribution through geological timePhysics of the Earth and Planetary Interiors, Vol. 55, pp. 37-53. Database # 18199GlobalGeophysics-paleomagnetics, Pangaea
DS201312-0331
2013
Grant, T.Grant, T., Milke, R., Wunder, B., Morales, L., Wirth, R.The kinetic effects of H20 in metasomatic and xenolith breakdown reactions.Goldschmidt 2013, AbstractMantleFluids
DS2001-0726
2001
GranthamManhica, A.S.T.D., Grantham, Armstrong, Guise, KrugerPolyphase deformation and metamorphism at the Kalahari Craton - Mozambique Belt boundary.Geological Society of London, Special Publication, Special Paper 184, pp. 303-22.South Africa, MozambiqueMetamorphism, Craton
DS1960-0051
1960
Grantham, D.R.Grantham, D.R., Allen, J.B.Kimberlites in Sierra LeoneOverseas Geol. Min. Res., Vol. 8, PP. 5-25.Sierra Leone, West Africa, KoiduGeology
DS1960-0052
1960
Grantham, D.R.Grantham, D.R., Allen, J.B.Kimberlite in Sierra LeoneGeological Survey SIERRA LEONE SHORT PAPER., No. 6West Africa, Sierra LeoneGeology, Petrography
DS1960-0831
1967
Grantham, D.R.Grantham, D.R.The Diamond Host Rocks of GhanaAfr. Geol. Symposium 4th., Held In Sheffield., 2P. abstract.Ghana, West AfricaHistory, Geology
DS1960-1113
1969
Grantham, D.R.Grantham, D.R.The Age of the Diamond Bearing Rocks of PannaCurrent Science., Vol. 38, No. 16, PP. 377-379.IndiaGeochronology
DS201901-0037
2018
Grantham, G.Grantham, G., Eglinton, B., Macey, P.H., Ingram,B., Radeneyer, M., Kaiden, H., Manhica, V.The chemistry of Karoo age andesitic lavas along the northern Mozambique coast, southern Africa and possible implications for Gondwana breakup.South African Journal of Geology, Vol. 121, pp. 271-286.Africa, Mozambiquegeodynamics

Abstract: Major, trace, radiogenic isotope and stable isotope data from lavas along the northeastern coast of Mozambique are described. The whole rock composition data demonstrate that the rocks are dominantly andesitic with compositions typical of calc-alkaline volcanic rocks from arc environments. SHRIMP U/Pb data from zircons indicate that the zircons are xenocrystic, having ages of between 500 Ma and 660 Ma, with the age of the lava constrained by Rb/Sr data at ~184 Ma. Strontium, Nd and Pb radiogenic isotope data support an interpretation of extensive mixing between a Karoo age basaltic magma (dolerite) from Antarctica and continental crust similar in composition to the Mozambique basement. Oxygen isotope data also imply a significant crustal contribution to the lavas. Possible tectonic settings for the lavas are at the margin of a plume or from a locally restricted compressional setting during Gondwana breakup processes.
DS1998-0933
1998
Grantham, G.H.Manhica, A., Grantham, G.H., Guise, P.D.An 40Ar 39Ar study of Zimbabwe Craton Mozambique Belt boundary inManica-Chimoio area, western Mozambique.Journal of African Earth Sciences, Vol. 27, 1A, p. 135. AbstractGlobalGeochronology
DS200412-0711
2003
Grantham, G.H.Grantham, G.H., Maboko, M., Eglington, B.M.A review of the evolution of the Mozambique belt and implications for the amalgamation and dispersal of Rodinia and Gondwana.Proterozoic East Gondwana: Supercontinent assembly and Breakup. Ed. Yoshida , Geological Society of London Spe, No. 206, pp. 401-426.Gondwana, RodiniaPlume, tectonics
DS201012-0248
2010
Grantham, G.H.Grantham, G.H., Manhica, A.D.S.T., Armstrong, R.A., Kruger, F.J., Loubser, M.New SHRIMP, Rb/Sr and Sm/Nd isotope and whole rock chemical dat a from central Mozambique and western Dronning Maud Land: implications for eastern KalahariJournal of African Earth Sciences, Vol. 59, 1, pp.74-100.Africa, Mozambique, AntarcticaCraton, amalgamation of Gondwana
DS1960-0456
1964
Granthan, D.R.Granthan, D.R.The Diamond Deposits of Panna, Central IndiaIndustrial Diamond Review., Vol. 24, No. 279, FEBRUARY PP. 28-35.IndiaBlank
DS2003-0246
2003
Grapes, R.Chen, G., Grapes, R., Zhang, K.A model for Mesozoic crustal melting and tectonic deformation in southeast ChinaInternational Geology Review, Vol. 45, 10, Oct. pp. 948-957.ChinaBlank
DS200412-0317
2003
Grapes, R.Chen, G., Grapes, R., Zhang, K.A model for Mesozoic crustal melting and tectonic deformation in southeast China.International Geology Review, Vol. 45, 10, Oct. pp. 948-957.ChinaTectonics
DS1991-0500
1991
Graphchikov, A.A.Fonarev, V.I., Graphchikov, A.A., Konilov, A.N.A consistent system of geothermometers for metamorphic complexesInternational Geology Review, Vol. 33, No. 8, August pp. 743-783RussiaGeothermometry, Metamorphic complexes
DS200712-0381
2007
Graps, A.L.Graps, A.L., Morbidelli, A.A chondritic and nonchondritic Earth: what would the dynamicists say?Plates, Plumes, and Paradigms, 1p. abstract p. A352.MantleWater
DS2000-0357
2000
Grasby, S.Grasby, S., Osadetz, K., Betcher, R., Render, F.Reversal of the regional scale flow system of the Williston Basin in response to Pleistocene glaciationGeology, Vol. 28, No. 7, July, pp. 635-8.Alberta, Saskatchewan, Manitoba, MontanaGeomorphology, glaciation
DS202107-1090
2021
Grasby, S.E.Bedard, J.H., Troll, V.R., Deegan F.M., Tegner, C., Sauumur, B. M., Evenchick, C.A., Grasby, S.E., Dewing, K.High Arctic large igneous province alkaline rocks in Canada: evidence for multiple mantle components.Journal of Petrology, 113p. In press availableCanada, Ellesmerealkaline rocks

Abstract: The Cretaceous High Arctic Large Igneous Province (HALIP) in Canada, although dominated by tholeiites (135-90?Ma), contains two main groups of alkaline igneous rocks. The older alkaline rocks (?96?Ma) scatter around major fault and basement structures. They are represented by the newly-defined Fulmar Suite alkaline basalt dykes and sills, and include Hassel Formation volcanics. The younger alkaline group is represented by the Wootton Intrusive Complex (92.2-92.7?Ma), and the Audhild Bay Suite (83-73?Ma); both emplaced near the northern coast of Ellesmere Island. Fulmar Suite rocks resemble EM-type ocean island basalts (OIB) and most show limited crustal contamination. The Fulmar Suite shows increases of P2O5 at near-constant Ba-K-Zr-Ti that are nearly orthogonal to predicted fractionation- or melting-related variations; which we interpret as the result of melting composite mantle sources containing a regionally widespread apatite-bearing enriched component (P1). Low-P2O5 Fulmar Suite variants overlap compositionally with enriched HALIP tholeiites, and fall on common garnet lherzolite trace element melting trajectories, suggesting variable degrees of melting of a geochemically similar source. High-P2O5 Hassel Formation basalts are unusual among Fulmar rocks, because they are strongly contaminated with depleted lower crust; and because they involve a high-P2O5-Ba-Eu mantle component (P2), similar to that seen in alkali basalt dykes from Greenland. The P2 component may have contained Ba-Eu-rich hawthorneite and/or carbonate minerals as well as apatite, and may typify parts of the Greenlandic sub-continental lithospheric mantle (SCLM). Mafic alkaline Audhild Bay Suite (ABS) rocks are volcanic and hypabyssal basanites, alkaline basalts and trachy-andesites, and resemble HIMU ocean island basalts in having high Nb, low Zr/Nb and low 87Sr/86Sri. These mafic alkaline rocks are associated with felsic alkaline lavas and syenitic intrusions, but crustally-derived rhyodacites and rhyolites also exist. The Wootton Intrusive Complex (WIC) contains geochemically similar plutonic rocks (alkali gabbros, diorites and anatectic granites), and may represent a more deeply eroded, slightly older equivalent of the ABS. Low-P2O5 ABS and WIC alkaline mafic rocks have flat heavy rare-earth (HREE) profiles suggesting shallow mantle melting; whereas High-P2O5 variants have steep HREE profiles indicating deeper separation from garnet-bearing residues. Some High-P2O5 mafic ABS rocks seem to contain the P1 and P2 components identified in Fulmar-Hassel rocks, whereas other samples trend towards possible High-P2O5+Zr (PZr) and High-P2O5+K2O (PK) components. We argue that the strongly alkaline northern Ellesmere Island magmas sampled mineralogically heterogeneous veins or metasomes in Greenlandic-type SCLM, which contained trace phases like apatite, carbonates, hawthorneite, zircon, mica or richterite. The geographically more widespread apatite-bearing component (P1), could have formed part of a heterogeneous plume or upwelling mantle current that also generated HALIP tholeiites when melted more extensively, but may also have resided in the SCLM as relics of older events. Rare HALIP alkaline rocks with high K-Rb-U-Th fall on mixing paths implying strong local contamination from either Sverdrup Basin sedimentary rocks or granitic upper crust. However, the scarcity of potassic alkaline HALIP facies, together with the other trace element and isotopic signatures, provide little support for an ubiquitous fossil sedimentary subduction zone component in the HALIP mantle source.
DS202108-1274
2021
Grasby, S.E.Bedard, J.H., Troll, V.R., Deegan, F.M., Tegner, C., Saumor, B.M., Evenchick, C.A., Grasby, S.E., Dewing, K.High arctic large igneous province alkaline rocks in Canada: evidence for multiple mantle components.Journal of Petrology, 113p. PdfCanada, Ellesmere Islandalkaline rocks

Abstract: The Cretaceous High Arctic Large Igneous Province (HALIP) in Canada, although dominated by tholeiites (135-90?Ma), contains two main groups of alkaline igneous rocks. The older alkaline rocks (?96?Ma) scatter around major fault and basement structures. They are represented by the newly-defined Fulmar Suite alkaline basalt dykes and sills, and include Hassel Formation volcanics. The younger alkaline group is represented by the Wootton Intrusive Complex (92.2-92.7?Ma), and the Audhild Bay Suite (83-73?Ma); both emplaced near the northern coast of Ellesmere Island. Fulmar Suite rocks resemble EM-type ocean island basalts (OIB) and most show limited crustal contamination. The Fulmar Suite shows increases of P2O5 at near-constant Ba-K-Zr-Ti that are nearly orthogonal to predicted fractionation- or melting-related variations; which we interpret as the result of melting composite mantle sources containing a regionally widespread apatite-bearing enriched component (P1). Low-P2O5 Fulmar Suite variants overlap compositionally with enriched HALIP tholeiites, and fall on common garnet lherzolite trace element melting trajectories, suggesting variable degrees of melting of a geochemically similar source. High-P2O5 Hassel Formation basalts are unusual among Fulmar rocks, because they are strongly contaminated with depleted lower crust; and because they involve a high-P2O5-Ba-Eu mantle component (P2), similar to that seen in alkali basalt dykes from Greenland. The P2 component may have contained Ba-Eu-rich hawthorneite and/or carbonate minerals as well as apatite, and may typify parts of the Greenlandic sub-continental lithospheric mantle (SCLM). Mafic alkaline Audhild Bay Suite (ABS) rocks are volcanic and hypabyssal basanites, alkaline basalts and trachy-andesites, and resemble HIMU ocean island basalts in having high Nb, low Zr/Nb and low 87Sr/86Sri. These mafic alkaline rocks are associated with felsic alkaline lavas and syenitic intrusions, but crustally-derived rhyodacites and rhyolites also exist. The Wootton Intrusive Complex (WIC) contains geochemically similar plutonic rocks (alkali gabbros, diorites and anatectic granites), and may represent a more deeply eroded, slightly older equivalent of the ABS. Low-P2O5 ABS and WIC alkaline mafic rocks have flat heavy rare-earth (HREE) profiles suggesting shallow mantle melting; whereas High-P2O5 variants have steep HREE profiles indicating deeper separation from garnet-bearing residues. Some High-P2O5 mafic ABS rocks seem to contain the P1 and P2 components identified in Fulmar-Hassel rocks, whereas other samples trend towards possible High-P2O5+Zr (PZr) and High-P2O5+K2O (PK) components. We argue that the strongly alkaline northern Ellesmere Island magmas sampled mineralogically heterogeneous veins or metasomes in Greenlandic-type SCLM, which contained trace phases like apatite, carbonates, hawthorneite, zircon, mica or richterite. The geographically more widespread apatite-bearing component (P1), could have formed part of a heterogeneous plume or upwelling mantle current that also generated HALIP tholeiites when melted more extensively, but may also have resided in the SCLM as relics of older events. Rare HALIP alkaline rocks with high K-Rb-U-Th fall on mixing paths implying strong local contamination from either Sverdrup Basin sedimentary rocks or granitic upper crust. However, the scarcity of potassic alkaline HALIP facies, together with the other trace element and isotopic signatures, provide little support for an ubiquitous fossil sedimentary subduction zone component in the HALIP mantle source.
DS202111-1757
2021
Grasby, S.E.Bedard, J.H., Troll, V,R., Deegan, F.M., Tegner, C., Saumur, B.M., Evenchick, C.A., Grasby, S.E., Dewing, K.High Arctic large igneous province alkaline rocks in Canada: evidence for multiple mantle components.Journal of Petrology, Vol. 62, 9, pp. 1-31. pdfCanada, Ellesmere Islandalkaline rocks

Abstract: The Cretaceous High Arctic Large Igneous Province (HALIP) in Canada, although dominated by tholeiites (135-90?Ma), contains two main groups of alkaline igneous rocks. The older alkaline rocks (?96?Ma) scatter around major fault and basement structures. They are represented by the newly defined Fulmar Suite alkaline basalt dykes and sills, and include Hassel Formation volcanic rocks. The younger alkaline group is represented by the Wootton Intrusive Complex (92•2-92•7?Ma), and the Audhild Bay Suite (83-73?Ma), both emplaced near the northern coast of Ellesmere Island. Fulmar Suite rocks resemble EM-type ocean island basalts (OIB) and most show limited crustal contamination. The Fulmar Suite shows increases of P2O5 at near-constant Ba-K-Zr-Ti that are nearly orthogonal to predicted fractionation- or melting-related variations, which we interpret as the result of melting composite mantle sources containing a regionally widespread apatite-bearing enriched component (P1). Low-P2O5 Fulmar Suite variants overlap compositionally with enriched HALIP tholeiites, and fall on common garnet lherzolite trace element melting trajectories, suggesting variable degrees of melting of a geochemically similar source. High-P2O5 Hassel Formation basalts are unusual among Fulmar rocks, because they are strongly contaminated with depleted lower crust; and because they involve a high-P2O5-Ba-Eu mantle component (P2), similar to that seen in alkali basalt dykes from Greenland. The P2 component may have contained Ba-Eu-rich hawthorneite and/or carbonate minerals as well as apatite, and may typify parts of the Greenlandic sub-continental lithospheric mantle (SCLM). Mafic alkaline Audhild Bay Suite (ABS) rocks are volcanic and hypabyssal basanites, alkaline basalts and trachy-andesites, and resemble HIMU ocean island basalts in having high Nb, low Zr/Nb and low 87Sr/86Sri. These mafic alkaline rocks are associated with felsic alkaline lavas and syenitic intrusions, but crustally derived rhyodacites and rhyolites also exist. The Wootton Intrusive Complex (WIC) contains geochemically similar plutonic rocks (alkali gabbros, diorites and anatectic granites), and may represent a more deeply eroded, slightly older equivalent of the ABS. Low-P2O5 ABS and WIC alkaline mafic rocks have flat heavy rare earth element (HREE) profiles suggesting shallow mantle melting; whereas High-P2O5 variants have steep HREE profiles indicating deeper separation from garnet-bearing residues. Some High-P2O5 mafic ABS rocks seem to contain the P1 and P2 components identified in Fulmar-Hassel rocks, whereas other samples trend towards possible High-P2O5 + Zr (PZr) and High-P2O5 + K2O (PK) components. We argue that the strongly alkaline northern Ellesmere Island magmas sampled mineralogically heterogeneous veins or metasomes in Greenlandic-type SCLM, which contained trace phases such as apatite, carbonates, hawthorneite, zircon, mica or richterite. The geographically more widespread apatite-bearing component (P1) could have formed part of a heterogeneous plume or upwelling mantle current that also generated HALIP tholeiites when melted more extensively, but may also have resided in the SCLM as relics of older events. Rare HALIP alkaline rocks with high K-Rb-U-Th fall on mixing paths implying strong local contamination from either Sverdrup Basin sedimentary rocks or granitic upper crust. However, the scarcity of potassic alkaline HALIP facies, together with the other trace element and isotopic signatures, provides little support for a ubiquitous fossil sedimentary subduction-zone component in the HALIP mantle source.
DS200612-0375
2005
Graser, G.Emmel, B., Jacobs, J., Kastowski, M., Graser, G.Phanerozoic upper crustal tectonothermal development of basement rocks from central Madagascar: an integrated fission track and structural study.Tectonophysics, in pressAfrica, MadagascarGeothermometry, Gondwana
DS201212-0151
2012
Graser, P.De Bruin, D., Graser, P.Quality control procedures applied to routine electron probe analyses of kimberlite indicator minerals.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractTechnologyGeochemistry - KIMS
DS202104-0580
2019
Grass, C.Grass, C., Woodland, A., Hoferm H,m Seitz, H-M., Pearson, G., Kjarsgaard, B.Metasomatism and oxidation state of the lithospheric mantle beneath the Rae Craton, Canada as revealed by xenoliths from Somerset Island and Pelly Bay. ***note dateGeophysical Research abstracts, EGU, EGU2019-9348, 1p. PdfCanadageodynamics

Abstract: We present the first oxidation state measurements for the subcontinental lithospheric mantle (SCLM) beneath the Rae craton, northern Canada, one of the largest components of the Canadian shield. In combination with major and trace element compositions for garnet and clinopyroxene, we assess the relationship between oxidation state and metasomatic overprinting. The sample suite comprises peridotite xenoliths from the central part (Pelly Bay) and the craton margin (Somerset Island) providing insights into lateral and vertical variations in lithospheric character. Our suite contains spinel, garnet-spinel and garnet peridotites, with most samples originating from 100 to 140 km depth. Within this narrow depth range we observe strong chemical gradients, including variations in oxygen fugacity (ƒO2) of over 4 log units. Both Pelly Bay and Somerset Island peridotites reveal a change in metasomatic type with depth. Observed geochemical systematics and textural evidence support the notion that Rae SCLM developed through amalgamation of different local domains, establishing chemical gradients from the start. These gradients were subsequently modified by migrating melts that drove further development of different types of metasomatic overprinting and variable oxidation at a range of length scales. This oxidation already apparent at ~?100 km depth could have locally destabilised any pre-existing diamond or graphite.
DS1994-0655
1994
Grasset, O.Grasset, O., Albarede, F.Hybridization of mingling magmas with different densitiesEarth and Planetary Science Letters, Vol. 121, No. 3-4, February pp. 327-332GlobalMagma generation
DS2002-0414
2002
Grasset, O.Eberle, M.A., Grasset, O., Sotin, C.A numerical study of the interaction between the mantle wedge, subducting slab and overriding plate.Physics of the Earth and Planetary Interiors, Vol. 134, 3-4, Dec. 22, pp. 191-202.MantleSubduction, Tomography
DS200912-0264
2009
Grassi, D.Grassi, D., Schmidt, M.W.Melting of carbonated pelites at 9-13 GPa: generating potassic carbonatitic melts for mantle metasomatism.Goldschmidt Conference 2009, p. A461 Abstract.MantleMetasomatism
DS201012-0249
2010
Grassi, D.Grassi, D., Schmidt, M.W.Melting of carbonated pelites at 8-13 GPa: generating K-rich carbonatites for mantle metasomatism.Contributions to Mineralogy and Petrology, In press available, 23p.MantleSubduction, potassic magmatism
DS201112-0384
2011
Grassi, D.Grassi, D., Schmidt, M.W.Melting of carbonates pelites at 8-13 GPa: generating K rich carbonatites for mantle metasomatism.Contributions to Mineralogy and Petrology, Vol. 162, 1p. pp. 169-191.TechnologyMetasomatism
DS201112-0385
2011
Grassi, D.Grassi, D., Schmidt, M.W.Melting of carbonated pelites from 70 to 700 km depth.Journal of Petrology, Vol. 52, 4, pp. 765-789.MantleMelting - not specific to diamonds
DS201904-0738
2019
Grassi, D.Galli, A., Grassi, D., Sartori, G., Gianola, O., Burg, J-P., Schmidt, M.W.Jurassic carbonatite and alkaline magmatism in the Ivrea zone ( European Alps) related to the breakup of Pangea.Geology, Vol. 47, 3, pp. 199-202..Europecarbonatite

Abstract: We report on pipe-like bodies and dikes of carbonate rocks related to sodic alkaline intrusions and amphibole mantle peridotites in the Ivrea zone (European Southern Alps). The carbonate rocks have bulk trace-element concentrations typical of low-rare earth element carbonatites interpreted as cumulates of carbonatite melts. Faintly zoned zircons from these carbonate rocks contain calcite inclusions and have trace-element compositions akin to those of carbonatite zircons. Laser ablation-inductively coupled plasma-mass spectrometry U-Pb zircon dating yields concordant ages of 187 ± 2.4 and 192 ± 2.5 Ma, coeval with sodic alkaline magmatism in the Ivrea zone. Cross-cutting relations, ages, as well as bulk and zircon geochemistry indicate that the carbonate rocks are carbonatites, the first ones reported from the Alps. Carbonatites and alkaline intrusions are comagmatic and were emplaced in the nascent passive margin of Adria during the Early Jurassic breakup of Pangea. Extension caused partial melting of amphibole-rich mantle domains, yielding sodic alkaline magmas whose fractionation led to carbonatite-silicate melt immiscibility. Similar occurrences in other rifts suggest that small-scale, sodic and CO2-rich alkaline magmatism is a typical result of extension and decompression-driven reactivation of amphibole-bearing lithospheric mantle during passive continental breakup and the evolution of magma-poor rifts.
DS200712-0824
2006
Grassineau, N.Peate, D.W., Breddam, K., Baker, J.A., Kurz, M., Grassineau, N., Barker, A.K.Compositional features of enriched Icelandic mantle components.Geochimica et Cosmochimica Acta, In press availableEurope, IcelandGeochemistry
DS200912-0848
2009
Grassineau, N.Zaitsev, A.N., Keller, J., Jones, G., Grassineau, N.Mineralogical and geochemical changes of natrocarbonatites due to fumarolic activity at Oldoinyo Lengai volcano, Tanzania.alkaline09.narod.ru ENGLISH, May 10, 2p. abstractAfrica, TanzaniaCarbonatite
DS201603-0380
2010
Grasso, C. B.Grasso, C. B.Petrology of alkaline complex Serra Negra. ( Salitre 1 e Salitre II) Whole rock geochemistry Thesis, Universidade de Brasilia *** IN POR, 164p. Pdf *** In PortugeseSouth America, BrazilCarbonatite
DS201312-0319
2013
Grasso, C.B.Gomide, C.S., Brod, J.A., Junqueira-Brod, T.C., Buhn, B.M., Santos, R.V., Barbosa, E.S.R., Cordeiro, P.F.O., Palmieri, M., Grasso, C.B., Torres, M.G.Sufur isotopes from Brazilian alkaline carbonatite complexes.Chemical Geology, Vol. 341, pp. 38-49.South America, BrazilDeposit - Tapira, Salitre, Serra Negra, Catalao, Jacupiringa
DS201012-0796
2010
Grasso, J.R.Traversa, F., Pinel, V., Grasso, J.R.A constant influx model for the dike propogation: implications for magma reservoir dynamics.Journal of Geophysical Research, Vol. 115, B1, B01201.MantleMagmatism
DS1975-1036
1979
Grasso, R.Grasso, R.El 452 Kia-ora Area, South Australia, Report on the Drilling of Circular Depressions for Oilmin Nl, Transoil Nl and Petromin Nl.South Australia Open File., No. E3466, 3P. UNPUBL.Australia, South AustraliaRotary Drilling, Prospecting, Geology, Diamonds, Kimberlite
DS1991-0599
1991
Grasty, R.L.Grasty, R.L., Holman, P.B., Blanchard, Y.B.Transportable calibration pads for ground and airborne gamma rayspectrometersGeological Survey of Canada Paper, No. 90-23, 25pCanadaSpectrometry, Program -PADWIN.
DS1900-0190
1903
Gratacap, L.P.Gratacap, L.P.A Possible Kimberley DiamondMineral. Coll., Vol. 10, JUNE PP. 60-61.United States, Kentucky, AppalachiaDiamond Occurrence
DS1991-0617
1991
Gratham, G.H.Groenewald, P.B., Gratham, G.H., Watkeys, M.K.Geological evidence for a Proterozoic to Mesozoic link between southeastern Africa and Dronning Maud Land, AntarcticaJournal of the Geological Society of London, Vol. 148, pp. 1115-1123Africa, AntarcticaCraton, Lithostratigraphy
DS1991-0600
1991
Grathwohl, O. and M.Grathwohl, O. and M.Antwerp diamond seminarCab and Crystal, Vol. 3, No. 6, December pp. 14-16BelgiumNews item, Brief overview
DS1991-0601
1991
Gratier, J.P.Gratier, J.P., Gamond, J.F.Transition between seismic and aseismic deformation in the upper crustDeformation Mechanisms, Rheology and Tectonics, editors Knipe, R.J., No. 54, pp. 461-473GlobalTectonics, Geophysics -seismics
DS1900-0407
1906
Graton, L.C.Graton, L.C.Reconnaissance of Some Gold and Tin Deposits of the Southern Appalachians. with Notes on the Dahlonega Mines by W. Lindgren.United States Geological Survey (USGS) Bulletin., No. 293, 134P.United States, AppalachiaDiamond Occurrence
DS201412-0832
2014
Grattan, K.Simandl, G.J., Paradis, S., Stone, R.S., Fajber, R., Kressall, R.D., Grattan, K., Crozier, J., Simandl, L.J.Applicablity of handheld X-ray fluroescence spectrometry in the exploration and development of carbonatite related niobium deposits: a case study of the Aley carbonatite, British Columbia, Canada.Geochemistry: Exploration, Environment, Analysis, Vol. 14, 3, pp. 211-221.Canada, British ColumbiaCarbonatite
DS1960-0673
1966
Grattan-Bellew, P.E.Grattan-Bellew, P.E.The Composition of Some Garnets from African KimberlitesKimberlite-carbonatite Conference Held New Delhi, (1964), I.M.A. Mineralogical Society of India VOLUME, PP. 23-28.South AfricaCrystallography, Mineralogy
DS1989-0533
1989
Gratton, J.Gratton, J.Crustal shortening, root spreading, isotasy and the growth of orogenicbelts: a dimensional analysisJournal of Geophysic. Research, Vol. 94, No. B 11, November 10, pp. 15, 627-15, 635GlobalOrogenic belts, Tectonics
DS200412-0767
2004
Gratton, M.N.Halls, H.C., McArdle, N.J., Gratton, M.N., Hill, M.J., Shaw, J.Microwave paleointensities from dyke chilled margins: a way to obtain long term variations in geodynamo intensity for the last tPhysics of the Earth and Planetary Science Interiors, Vol. 147, 2-3, Nov. 15, pp.183-195.Canada, OntarioMattachewan dyke swarm, geochronology, Biscotasing, Mar
DS1960-1097
1969
Gratton-Bellew, P.Edwards, N., Gratton-Bellew, P.Report on the Coral Rapids Investigation for Selection Trust Exploration Limited, Section Diamonds.Ontario Department of Mines, ASSESSMENT WORK FILE., No. 2.133, 15P. DECEMBER.Canada, OntarioGeochemistry, Sampling, Prospecting
DS1990-0204
1990
Gratz, A.J.Bird, P., Gratz, A.J.A theory for buckling the mantle lithosphere and Moho during compressive detachments in continentsTectonophysics, Vol. 177, pp. 325-336GlobalMantle, Tectonics
DS2002-0131
2002
Gratzer, R.Bechtel, A., Gratzer, R., Puttmann, W.,Oszczepalski, S.Geochemical characteristics across the oxic/anoxic interface Rote Faule front within the KuperschieferChemical Geology, Vol.185,1-2,pp.9-31.PolandGeochemistry, Deposit - Lubin Sieroszowice mining district
DS1992-0601
1992
Graubard, C.M.Graubard, C.M., Smith, G.M.The influence of Precambrian structure on Late Proterozoic Rift geometry of the western USAGeological Society of America (GSA) Abstracts with programs, 1992 Annual, Vol. 24, No. 7, abstract p. A365CordilleraTectonics
DS1992-0602
1992
Graubard, C.M.Graubard, C.M., Smith, G.M.The influence of Precambrian structure on tectonics of the western USAGeological Society of America (GSA) Abstract Volume, Vol. 24, No. 5, May p.28. abstract onlyWyomingTectonics, Structure
DS1999-0356
1999
GrauchKeller, G.R., Miller, Snelson, Sheehan, Levander, GrauchCrustal structure of the Rocky Mountain region, review and recent resultsGeological Society of America (GSA), Vol. 31, No. 7, p. 186. abstract.Alberta, WyomingTectonics
DS2002-1192
2002
Grauch, R.I.Orris, G.J., Grauch, R.I.Rare earth element mines, deposits and occurrencesU.s.g.s. Open File, Http://geopubs.wr.usgs.gov/open-file/of2-189, GlobalCarbonatite ( part of deposit database)
DS200412-1482
2002
Grauch, R.I.Orris, G.J., Grauch, R.I.Rare earth element mines, deposits and occurrences.U.S. Geological Survey, GlobalCarbonatite, ( part of deposit database)
DS1990-0103
1990
Grauch, V.J.Abrams, G.A., Grauch, V.J., Bankey, V.Complete bouguer gravity anomaly map of the Uinta and Piceance basins andvicinity, Utah and ColoradoUnited States Geological Survey (USGS) Open File, No. MF-2008-D, 1 : 500, 000Utah, Colorado PlateauGeophysics -gravity, Map
DS1993-0568
1993
Grauch, V.J.Grauch, V.J., et al.Materials provided at the workshop Geophysical map interpretation on thePC, April 21-22, 1993United States Geological Survey (USGS) Open File, No. 93-0560-B, 4 discs. $ 40.00GlobalComputer Program, Geophysical map workshop
DS201905-1025
2019
Grauchm V.J.S.Drenth, B.J., Grauchm V.J.S.Finding the gap in America's magnetic maps. ( Apr. 16, 2019)EOS, https://spaces.hightail. com/receive/ 2jvDHdtWRrUnited States, Arkansas, Missouri, Tennesseegeophysics, magnetic
DS1987-0108
1987
Grauert, B.Chernyshev, I.V., Kononova, V.A., Kramm, W., Grauert, B.Isotopic geochronology of Ural alkaline rocks based ion zircon uranium leaddata.(Russian)Geochemiya, (Russian), No. 3, pp. 323-338GlobalBlank
DS1990-1219
1990
Graup, G.Reimold, W.U., McGee, T., Graup, G.Search for dynamic deformation effects in contact breccias from South african kimberlite pipes21st. Lunar And Planetary Science Conference, March 12-16, Houston, March 16 presentationSouth AfricaAlteration, Kimberlite-breccias
DS2003-0379
2003
Graup, G.El Goresy, A., Dubrovinsky, L.S., Gillet, P., Mostefaoul, S., Graup, G.A new natural super hard transparent polymorph of carbon from the Popigai impactComptes Rendus Geosciences, IN FRENCH, Vol. 335, 12, Oct. pp. 889-898.RussiaBlank
DS200412-0515
2003
Graup, G.El Goresy, A., Dubrovinsky, L.S., Gillet, P., Mostefaoul, S., Graup, G., Drakopoulos, M., Simionovici, A.S.A new natural super hard transparent polymorph of carbon from the Popigai impact crater, Russia.Comptes Rendus Geoscience, Vol. 335, 12, Oct. pp. 889-898.RussiaLonsdaleite, graphite, mineralogy
DS201412-0222
2003
Graup, G.El Goresy, A., Dubrovinsky, L.S., Gillet, P., Mostefaoui, S., Graup, G., Drakopoulos, M., Simionovici, A.S., Swamy, V., Masaitis, V.L.A new natural, super-hard, transparent polymorph of carbon from the Popigai impact crater, Russia.Comptes Rendus Geoscience, Vol. 335, pp. 889-898.Russia, YakutiaMeteorite
DS1985-0244
1985
Gravchev, A.F.Gravchev, A.F., Nikolaichik, V.V., Trubu*itsyn, V.P.The nature of a regular form of ultrabasic xenoliths in basalts and the regularities of their size distribution.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 285, No. 6, pp. 1433-1435RussiaBlank
DS200612-0492
2005
Gravel, J.Gravel, J., et al.Acme Analytical Laboratories Ltd. & GGL. Diamonds - Soil and lake sediment geochemistry in diamond exploration, NWT, Canada.32ndYellowknife Geoscience Forum, p. 23 abstractCanada, Northwest TerritoriesGeochemistry - GGL Diamonds
DS201512-1937
2015
Gravel, J.Mackay, D.A.R., Simandl, G.J.,Ma, W., Gravel, J., Redfearn, M.Indicator minerals in exploration for speciality metal deposits: a QEMSCAN approach.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 211-218.TechnologyRare earths

Abstract: Quantitative Evaluation of Materials by Scanning electron microscopy (QEMSCAN®) was used to assess carbonatite indicator minerals in fl uvial sediments from the drainage area of the Aley carbonatite, in north-central British Columbia. QEMSCAN® is a viable method for rapid detection and characterization of carbonatite indicator minerals with minimal processing other than dry sieving. Stream sediments from directly above, and up to 11 km downstream, of the carbonatite deposit were selected for this indicator mineral study. The geology of the Aley carbonatite is described by Mäder (1986), Kressal et al. (2010), McLeish (2013), Mackay and Simandl (2014), and Chakhmouradian et al. (2015). Traditional indicator mineral exploration methods use the 0.25-2.0 mm size fraction of unconsolidated sediments (Averill, 2001, 2014; McCurdy, 2006, 2009; McClenaghan, 2011, 2014). Indicator minerals are detectable by QEMSCAN® at particle sizes smaller than those used for hand picking (<0.25 mm). Pre-concentration (typically by shaker table) is used before heavy liquid separation, isodynamic magnetic separation, optical identifi cation using a binocular microscope, and hand picking (McClenaghan, 2011). Following additional sieving, the 0.5-1 and 1-2 mm fractions are hand picked for indicator minerals while the 0.25-0.5 mm fraction is subjected to paramagnetic separation before hand picking (Averill, 2001; McClenaghan, 2011). Hand picking indicator minerals focuses on monomineralic grains, and composite grains may be lost during processing. Composite grains are diffi cult and time consuming to hand pick and characterize using optical and Scanning Electron Microscopy (SEM) methods. A single grain mount can take 6-12 hours to chemically analyse (Layton- Matthews et al., 2014). Detailed sample analysis using the QEMSCAN® Particle Mineral Analysis routine allows for 5-6 samples to be analyzed per day. When only mineral identifi cation and mineral concentrations and counts are required, the use of a Bulk Mineral Analysis routine reduces the analysis time from ~4 hours to ~30 minutes per sample.
DS201605-0864
2016
Gravel, J.Mackay, D.A.R., Simandl, G.J., Ma, W., Redfearn, M., Gravel, J.Indicator mineral-based exploration for carbonatites and related specialty metal deposits - a QEMSCAN orientation survey, British Columbia. Aley, Lonnie, WicheedaJournal of Geochemical Exploration, Vol. 165, pp. 159-173.Canada, British ColumbiaGeochemistry - carbonatites

Abstract: This orientation survey indicates that Quantitative Evaluation of Materials by Scanning electron microscopy (QEMSCAN®) is a viable alternative to traditional indicator mineral exploration approaches which involve complex processing followed by visual indicator mineral hand-picking with a binocular microscope. Representative polished smear sections of the 125-250 ?m fraction (dry sieved and otherwise unprocessed) and corresponding Mozley C800 table concentrates from the drainages of three carbonatites (Aley, Lonnie, and Wicheeda) in the British Columbia Alkaline Province of the Canadian Cordillera were studied. Polished smear sections (26 × 46 mm slide size) contained an average of 20,000 exposed particles. A single section can be analyzed in detail using the Particle Mineral Analysis routine in approximately 3.5-4.5 h. If only mineral identification and mineral concentrations are required, the Bulk Mineral Analysis routine reduces the analytical time to 30 min. The most useful carbonatite indicator minerals are niobates (pyrochlore and columbite), REE-fluorocarbonates, monazite, and apatite. Niobate minerals were identified in the 125-250 ?m fraction of stream sediment samples more than 11 km downstream from the Aley carbonatite (their source) without the need for pre-concentration. With minimal processing by Mozley C800, carbonatite indicator minerals were detected downstream of the Lonnie and Wicheeda carbonatites. The main advantages of QEMSCAN® over the traditional indicator mineral exploration techniques are its ability to: 1) analyze very small minerals, 2) quickly determine quantitative sediment composition and mineralogy by both weight percent and mineral count, 3) establish mineral size distribution within the analyzed size fraction, and 4) determine the proportions of monomineralic (liberated) grains to compound grains and statistically assess mineral associations in compound grains. One of the key advantages is that this method permits the use of indicator minerals based on their chemical properties. This is impossible to accomplish using visual identification.
DS201801-0063
2017
Gravel, J.Simandl, G.J., Mackay, D.A.R., Ma, X., Luck, P., Gravel, J., Akam, C.The direct indicator mineral concept and QEMSCAN applied to exploration for carbonatite and carbonatite related ore deposits.in: Ferbey, T. Plouffe, A., Hickein, A.S. eds. Indicator minerals in tills and stream sediments of the Canadian Cordillera. Geological Association of Canada Special Paper,, Vol. 50, pp. 175-190.Canada, British Columbiacarbonatite - Aley, Lonnie, Wicheeda

Abstract: This volume consists of a series of papers of importance to indicator minerals in the Canadian Cordillera. Topics include the glacial history of the Cordilleran Ice Sheet, drift prospecting methods, the evolution of survey sampling strategies, new analytical methods, and recent advances in applying indicators minerals to mineral exploration. This volume fills a notable knowledge gap on the use of indicator minerals in the Canadian Cordillera. We hope that the volume serves as a user guide, encouraging the wider application of indicator minerals by the exploration community.
DS1987-0170
1987
GravelleDupont, P.L., Lapierre, H., Gravelle, BertrandCaracterisation du magmatism Proterozoique superieur en Afrique de l'ouestet implications geodynamiques: rrifts intracratoniques au Panafricain?Canadian Journal of Earth Sciences, Vol. 24, pp. 96-109.GlobalAlkaline rocks, magmatism
DS1995-0551
1995
Gravelle, J.Forster, D., Gravelle, J.Structuring foreign investments in the mining industryMining Tax Strategies, Held Feb. 1995, 25pCanadaTaxation, Economics -foreign investments
DS201212-0258
2012
Gravelle, J.Gravelle, J.Examining flow through shares in the mining sector.Canadian Mining Journal, June/July p. 34.CanadaFlow thru
DS1975-1037
1979
Gravenor, C.P.Gravenor, C.P., Gostin, V.A.Mechanisms to Explain the Loss of Heavy Minerals from Upper paleozoic Tillites of South Africa and Australia and the Late Precambrian Tillites of Australia.Sedimentology, Vol. 26, PP. 707-717.Australia, South AfricaHeavy Mineral Concentrates
DS200912-0265
2008
Graves, B.Graves, B.NI43-101 - some tricks and traps.Investing in Mining, mineweb.com, Vol. 2. pp. 16-17.CanadaLegal
DS1930-0273
1938
Graves, H.B. JR.Graves, H.B. JR.The Precambrian Structure of MissouriAcademy of Science ST. LOUIS Transactions, Vol. 29, No. 5, PP. 111-164.Missouri, United States, Central StatesBlank
DS200712-0084
2006
GravieBlowes, D.,Moncur, M., Smith, L., Sego, D., Klassen, Neuner, Gravie, Gould, ReinsonMining in the continuous permafrost: construction and instrumentation of two large scale waste rock piles.34th Yellowknife Geoscience Forum, p. 6. abstractCanada, Northwest TerritoriesMining - Diavik
DS200412-0712
2003
Gravity Capital Ltd.Gravity Capital Ltd.Behind the broken engagement... merger with Dwyka Diamonds.Australia's Paydirt, July, 28, 1p.AustraliaNews item Dwyka Diamonds
DS1920-0230
1925
Grawe, O.R.Grawe, O.R.Some Breccia of the St. Louis Formation in the St. Louis Missouri Region.Washington University Studies, Vol. 13, SCI. SER., No. 1, PP. 45-62.Missouri, United States, Central StatesCryptoexplosion
DS1920-0231
1925
Gray, A.Gray, A.Sixty Years Ago: Wanderings of a Stonyhurst Boy in Many LandLondon: John Murray, 306P.South Africa, BotswanaKimberley, Travelogue
DS1975-0152
1975
Gray, A.Nixon, P.H., Gray, A.Significance of Iron Oxide Carbonate Chert Argillite Metasediment Xenoliths from the Sub-karroo Basement of Lesotho.Leeds University Research Institute of African Geology Annual Report, Vol. 19, PP. 42-44.LesothoSekameng, Liqhobong, Kao, Matsuko, Mothae, Melkfontein, Petrograp
DS1992-1127
1992
Gray, A.Nixon, P.H., Davies, G.R., Rex, D.C., Gray, A.Venezuelan kimberlitesJournal of Volcanology and geothermal research, Vol. 50, No. 1/2, April 15, pp. 101-116VenezuelaKimberlites, Occurrences
DS1989-1045
1989
Gray, B.A.Montgomery, C.W., Gray, B.A.Ages and Strontium isotope systematics of Archean basement rocks from the south central Beartooth MountainsThe Mountain Geologist, Vol. 26, No. 3, July pp. 75-80MontanaGeochronology, Beartooth Mountains
DS1970-0776
1973
Gray, C.M.Moore, A.C., Gray, C.M.Carbonatites of the Strangways Range, Central Australia: Evidence from Strontium Isotopes.Geological Society AUST. Journal, Vol. 20, PP. 71-73.AustraliaRelated Rocks
DS1985-0545
1985
Gray, C.M.Price, R.C., Johnson, R.W., Gray, C.M., Frey, F.A.Geochemistry of Phonolites and Trachytes from the Summit Region of Mt. Kenya.Contributions to Mineralogy and Petrology, Vol. 89, No. 4, PP. 394-409.East Africa, KenyaGeochemistry
DS1991-1380
1991
Gray, C.M.Price, R.C., Gray, C.M., Wilson, R.E., Frey, F.A.The effects of weathering on rare earth element, Yttrium and Barium abundances in Tertiary basalts from southeastern AustraliaChemical Geology, Vol. 93, No. 3/4, December 5, pp. 245-266AustraliaWeathering, Yttrium, Barium, Rare earths, basalts
DS1991-1381
1991
Gray, C.M.Price, R.C., Gray, C.M., Wilson, R.E., Frey, F.A., Taylor, S.R.The effects of weathering on rare-earth element Yttrium and Barium abundances in Tertiary basalts from southeastern AustraliaChemical Geology, Vol. 93, No. 3/4, December 5, pp. 245-266AustraliaTholeiitic basalts, Geochemistry, rare earths, weathering
DS1993-1128
1993
Gray, C.M.Nicholls, I.A., Greig, A.G., Gray, C.M., Price, R.C.Newer volcanics province- basalts, xenoliths and megacrystsAustralia Geological Survey AGSO, Record No. 1993/58, $ 16.95AustraliaNewer Volcanics, Xenoliths
DS1997-0925
1997
Gray, C.M.Price. R.C., Gray, C.M., Frey, F.A.Strontium isotopic and trace element heterogeneity in the plains basalts of Newer Volcanic Province, VictoriaGeochimica et Cosmochimica Acta, Vol. 61, No. 1, pp. 171-92.AustraliaGeochronology, Alkaline rocks
DS2003-0485
2003
Gray, D.Goscombe, B., Hand, M., Gray, D., Mawby, J.Metamorphic architecture of a transpressional orogen: the Kaoko belt, NamibiaJournal of Petrology, Vol. 44, 4, pp. 679-712.NamibiaTectonics
DS2003-0486
2003
Gray, D.Goscombe, B., Hand, M., Gray, D.Structure of the Kaoko Belt, Namibia: progressive evolution of a classic transpressionalJournal of Structural Geology, Vol. 25, 7, pp. 1049-81.NamibiaTectonics
DS200412-0698
2003
Gray, D.Goscombe, B., Hand, M.,Gray, D., Mawby, J.Metamorphic architecture of a transpressional orogen: the Kaoko belt, Namibia.Journal of Petrology, Vol. 44, 4, pp. 679-712.Africa, NamibiaTectonics
DS200412-0699
2003
Gray, D.Goscombe, B., Hand, M., Gray, D.Structure of the Kaoko Belt, Namibia: progressive evolution of a classic transpressional orogen.Journal of Structural Geology, Vol. 25, 7, pp. 1049-81.Africa, NamibiaTectonics
DS1997-0438
1997
Gray, D.R.Gray, D.R., Foster, D.A.Orogenic concepts - application and definition: Lachlan Fold Belt, EasternAustraliaAmerican Journal of Science, Vol. 297, No. 9, Nov. 1, pp. 859-891AustraliaTectonics, Lachlan fold belt
DS1997-0439
1997
Gray, D.R.Gray, D.R., Foster, D.A., Bucher, M.Recognition and definition of orogenic events in the Lachlan Fold BeltAustralian Journal ofEarth Science, Vol. 44, No. 4, Aug. pp. 489-502AustraliaTectonics, orogeny, Lachlan Fold Belt, model
DS1997-1077
1997
Gray, D.R.Soesoo, A., Bons, P.D., Gray, D.R., Foster, D.A.Divergent double subduction: tectonics and petrologic consequencesGeology, Vol. 25, No. 8, August pp. 755-758.MantleTectonics, Subduction
DS2000-0300
2000
Gray, D.R.Foster, D.A., Gray, D.R.Timing of orogenic events in the Lachlan Orogen (2000)Australian Journal of Earth Sciences, Vol. 47, No. 4, Aug. 1, pp. 813-22.AustraliaTectonics - orogeny
DS200512-1028
2004
Gray, D.R.Spaggiardi, C.V., Gray, D.R., Foster, D.A.Lachlan Orogen subduction accretion systematics revisited.Australia Journal of Earth Sciences, Vol. 51, 4, pp. 549-553.AustraliaSubduction - not specific to diamonds
DS200912-0261
2009
Gray, D.R.Goscombe, B.D., Gray, D.R.Metamorphic response in orogens of different obliquity, scale and geometry.Gondwana Research, Vol. 15, 2, pp. 151-167.MantleUHP
DS1980-0145
1980
Gray, F.Gray, F.Lherzolite and Wehrlitic Rock Series at Tincup Peak, Klamath Mountains, S.w. Oregon.Geological Society of America (GSA), Vol. 12, No. 3, P. 108. (abstract.).United States, Oregon, Rocky MountainsBlank
DS1985-0245
1985
Gray, F.Gray, F., Page, N.J., Wilson, S.A., Carlson, R.R.Contrasting Petrology and Platinum Group Elements (pge) Geochemistry of Zoned Ultramafic Complexes, Klamath Mountains, California and Oregon.Canadian Mineralogist., Vol. 23, PT. 2, MAY P. 304. (abstract.).United States, West Coast, California, OregonGeochemistry, Geochronology, Petrography
DS1991-1897
1991
Gray, F.Wynn, J.C., Olmore, S.D., Gray, F., Day, W.C.U.S. Geological Survey mineral resource and tectonic studies in Venezuela.-brief overviewUnited States Geological Survey (USGS) Circ, No. C1062, pp. 80-83VenezuelaTectonics, Kimberlite
DS1993-0569
1993
Gray, F.Gray, F.Diamond bearing kimberlite pipes. #2United States Geological Survey (USGS) Bulletin, No. B2062, pp. 75-77.VenezuelaDiatremes, Kimberlites
DS1993-0570
1993
Gray, F.Gray, F., Orris, G.J.Placer diamondUnited States Geological Survey (USGS) Bulletin, No. B2062, pp. 86-88.Venezuela, GuyanaAlluvials, Diamonds
DS1993-1170
1993
Gray, F.Orris, G.J., Page, N.J., Bolm, K.S., Gray, F.Mines, prospects and occurrences of the Venezuelan Guayana ShieldUnited States Geological Survey (USGS) Bulletin, No. B2062, pp. 29-53.Venezuela, GuyanaDiamonds
DS1994-0656
1994
Gray, F.Gray, F.Industrial diamonds..A review of 1993 activitiesMining Engineering, Vol. 46, No. 7, July p. 662.United StatesEconomics
DS1995-0672
1995
Gray, F.Gray, F.Industrial diamonds: a review of 1994 activitiesMining Engineering, Vol. 47, No. 7, July 1/2 pg. p. 661.United StatesDiamonds -industrial, Economics
DS1995-2086
1995
Gray, F.Wynn, J.C., Sidder, G.B., Gray, F., Page, N.J., Mendoza, V.Geology and mineral deposits of the Venezuelan Guayana shield... goldUnited States Geological Survey (USGS) Bulletin, No. 2124-A, approx. 150pVenezuela, GuyanaBook -table of contents, Geophysics, Lo Increible, Sierra Verdun, Cerro ArrendaJ.
DS1993-0571
1993
Gray, J.Gray, J., Lauriol, B., Bruneau, D., Ricard, J.Post glacial emergence of Ungava Peninsula, and its relationship to glacialhistory.Canadian Journal of Earth Sciences, Vol. 30, No. 8, August pp. 1676-1696.QuebecGeomorphology
DS2002-0610
2002
Gray, J.Gray, J.Queen's University mineralogy field trip to Ilmaussaq, south Greenland: a travelogueMineralalogical Association of Canada Newsletter, No. 66, Jan. pp. 1,8-11.GreenlandAlkaline rocks
DS1997-0136
1997
Gray, J.T.Bruneau, D., Gray, J.T.Ecoulements glaciares et deglaciation hative 11 Ka Bp? du nord est de la peninsule d'Ungava, Quebec.Canadian Journal of Earth Sciences, Vol. 34, pp. 1089-1100.Quebec, Ungava, LabradorGeomorphology - tills
DS2001-0406
2001
Gray, J.T.Gray, J.T., Gosse, J.C., Marquette, G.Weathering zones in the Torngat Mountains Labrador, ice sheet thickness and basal thermal regime.Geological Association of Canada (GAC) Annual Meeting Abstracts, Vol. 26, p.54, abstract.Quebec, Ungava, LabradorGeomorphology, Laurentide Ice Sheet
DS1940-0084
1944
Gray, J.W.Gray, J.W.Historic Romance of DiamondsIndiana: Graessle-mercer., United StatesKimberlite
DS201412-0949
2014
Gray, K.Viljoen, K.S., Harris, J.W., Richardson, S.H., Gray, K.Trace element chemistry of peridotitic garnets in diamonds from the Premier ( Cullinan) and Finsch kimberlites, South Africa: contrasting styles of mantle metasomatism.Lithos, Vol. 208-209, pp. 1-15.Africa, South AfricaDeposit - Premier, Finsch
DS1993-1515
1993
Gray, K.J.Southworth, C.S., Gray, K.J., Sutter, J.F.Middle Eocene intrusive igneous rocks of the Central Appalachian Valley and Ridge Province -setting, chemistry, structureU.s. Geological Survey Bulletin, Vol. 1839-J, 21pAppalachiaIgneous rocks, Geochemistry
DS201512-1981
2015
Gray, L.Van Wychen, W., Copland, L., Burgess, D.O., Gray, L., Schaffer, N., Fisher, T.Glacier velocities and dynamic discharge from the ice masses of Baffin Island and Bylot Island, Nunavut, Canada.Canadian Journal of Earth Sciences, Vol. 52, 11, pp. 980-989.Canada, Nunavut, Baffin IslandGeomorphology

Abstract: Speckle tracking of ALOS PALSAR fine beam data from 2007-2011 are used to determine the surface motion of major ice masses on Baffin Island and Bylot Island in the southern Canadian Arctic Archipelago. Glacier velocities are low overall, with peaks of ?100 m a?1 and means of ?20-60 m a?1 common along the main trunk of many outlet glaciers. Peak velocities on Penny and Bylot Island ice caps tend to occur near the mid-sections of their primary outlet glaciers, while the fastest velocities on all other glaciers usually occur near their termini due to relatively large accumulation areas draining through narrow outlets. Estimates of ice thickness at the fronts of tidewater-terminating glaciers are combined with the velocity measurements to determine a regional dynamic discharge rate of between ?17 Mt a?1 and ?108 Mt a?1, with a mid-point estimate of ?55 Mt a?1, revising downward previous approximations. These velocities can be used as inputs for glacier flow models, and provide a baseline dataset against which future changes in ice dynamics can be detected.
DS2002-0611
2002
Gray, R.Gray, R.Proximal and distal relationship between coarse gravel beach remnants of the Plio-Pleistocene Orange River delta.11th. Quadrennial Iagod Symposium And Geocongress 2002 Held Windhoek, Abstract p. 28.NamibiaAlluvials
DS201212-0259
2012
Gray, R.Gray, R., Pysklywec, R.N.Geodynamic models of mature continental collision: evolution of an orogen from lithospheric suduction to continental retreat/delamination.Journal of Geophysical Research, Vol. 117, B03408, 14p.MantleGeodynamics - subduction
DS1997-0440
1997
Gray, S.Gray, S.In line pressure JIG - the Australasian mining industry supporting innovative new technologyAustralian Institute of Mining and Metallurgy (AusIMM) Bulletin, No. 4, June pp. 35, 37-40AustraliaMining, Mineral processing - JIG
DS200412-0672
2004
Gray, W.Glazner, A.F., Bartley, J.M., Coleman, D.S., Gray, W., Taylor, R.Z.Are plutons assembled over millions of years by amalgamation from small magma chambers?Geology Today, Vol. 14, 4, pp. 4-11.TechnologyMagmatism - not specific to diamonds
DS202007-1165
2020
Grayver, A.V.Munch, F.D., Grayver, A.V., Guzavina, M., Kuvshinov, A.V., Khan, A.Joint inversion of daily and long period geomagnetic transfer functions reveals lateral variations in mantle water content.Journal of Geophysical Letters, Vol. 47, e2020GL087222Mantlewater

Abstract: The amount of water trapped in the Earth's interior has a strong effect on the evolution and dynamics of the planet, which ultimately controls the occurrence of earthquakes and volcanic eruptions. However, the distribution of water inside the Earth is not yet well understood. To study the Earth's deep interior, we make use of changes in the Earth's magnetic field to detect variations in electrical conductivity inside the planet. Electrical conductivity is a characteristic of a rock that varies with temperature and water content. Here, we present a novel methodology to estimate the amount of water in different regions of Earth's mantle. Our analysis suggests the presence of small amounts of water in the mantle underneath Europe, whereas larger amounts are expected beneath North America and northern Asia.
DS201708-1653
2017
Greaney, A.Greaney, A.Chalcophile elements in the mantle.11th. International Kimberlite Conference, PosterMantlechalcophile
DS200812-0428
2008
GreatFalls TribuneGreatFalls TribuneGrass Range mine shows promise of holding diamonds. Delta's Rodii is interviewed.GreatFalls, Tribune, May 26, 2p.United States, MontanaNews item - Delta
DS1950-0212
1955
GreatorexGreatorexDiamond Fever. #1London: Cassell And Co. Ltd., 223P.GuyanaKimberlite, Kimberley, History
DS1950-0327
1957
Greatorex, W.Greatorex, W.Diamond Fever. #2London: Cassell And Co, M., 223P.South America, Guyana, GuianaKimberlite
DS201112-0386
2011
Greau, Y.Greau, Y., Huang, J-X., Griffin, W.L., Renac, C., Alard, O., O'Reilly, S.Y.Type 1 eclogite from Roberts Victor kimberlites: products of extensive mantle metasomatism.Geochimica et Cosmochimica Acta, Vol. 75, 22, pp. 6927-2954.Africa, South AfricaDeposit - Roberts Victor
DS201212-0313
2012
Greau, Y.Huang, J.-X., Griffin, W.L., Greau, Y., O'Reilly, S.Y.Seeking the primary compositions of mantle xenoliths: isotopic and elemental consequences of sequential leaching treatments on an eclogite suite.Chemical Geology, in press availableAfrica, South AfricaDeposit - Roberts Victor
DS201212-0314
2012
Greau, Y.Huang, J-X., Greau, Y., Griffin, W.L., O'Reilly, S.Y., Pearson, N.J.Multi-stage origin of Roberts Victor eclogites: progressive metasomatism and its isotopic effects.Lithos, in press availableAfrica, South AfricaDeposit - Roberts Victor
DS201312-0333
2013
Greau, Y.Greau, Y., Alard, O., Griffin, W.L., Huang, J-X., O'Reilly, S.Y.Sulfides and chalcophile elements in Roberts Victor eclogites: unravelling a sulfide rich metasomatic event.Chemical Geology, Vol. 354, pp. 73-92.Africa, South AfricaDeposit - Roberts Victor
DS201312-0407
2013
Greau, Y.Huang, J-X., Griffin, W.L., Greau, Y., Pearson, N.J., O'Reilly, S.Y.Unmasking enigmatic xenolithic eclogites: progressive metasomatism on a key Roberts Victor sample.Goldschmidt 2013, AbstractAfricaKamafugite
DS201412-0314
2014
Greau, Y.Griffin, W.L., Batumike, J.M., Greau, Y., Pearson, N.J., Shee, S.R., O'Reilly, S.Y.Emplacement ages and sources of kimberlites and related rocks in southern Africa: U-Pb ages and Sr-Nd isotopes of groundmass perovskite.Contributions to Mineralogy and Petrology, Vol. 167, pp. 1032-37.Africa, southern AfricaDeposit - geochronology
DS201412-0380
2014
Greau, Y.Huang, J-X., Griffin, W.L., Greau, Y., Pearson, N.J., O'Reilly, S.Y., Cliff, J., Martin, L.Unmasking xenolithic eclogites: progressive metasomatism of a key Roberts Victor sample.Chemical Geology, Vol. 364, pp. 55-65.Africa, South AfricaDeposit - Roberts Victor
DS201412-0381
2014
Greau, Y.Huang, J-X., Li, P., Griffin, W.L., Xia, Q-K, Greau, Y., Pearson, N.J., O'Reilly, S.Y.Water contents of Roberts Victor xenolithic eclogites: primary and metasomatic controls.Contributions to Mineralogy and Petrology, Vol. 168, pp. 1092-1095Africa, South AfricaDeposit - Roberts Victor
DS201502-0063
2014
Greau, Y.Huang, J-X., Li, P., Griffin, W.L., Xia, Q-K, Greau, Y., Pearson, N.J., O'Reilly, S.Y.Water contents of Roberts Victor xenolithic eclogites: primary and metasomatic controls.Contributions to Mineralogy and Petrology, Vol. 168, pp. 1092-1105.Africa, South AfricaDeposit - Roberts Victor
DS201610-1872
2016
Greau, Y.Huang, J-X., Xiang, Y., An, Y., Griffin, W.L., Greau, Y., Xie, L., Pearson, N.J., Yu, H., O'Reilly, S.Y.Magnesium and oxygen isotopes in Roberts Victor eclogites.Chemical Geology, Vol. 438, pp. 73-83.Africa, South AfricaDeposit - Roberts Victor

Abstract: Magnesium and oxygen are critical elements in the solid Earth and hydrosphere. A better understanding of the combined behavior of Mg and O isotopes will refine their use as a tracer of geochemical processes and Earth evolution. In this study, the Mg-isotope compositions of garnet and omphacite separated from well-characterized xenolithic eclogites from the Roberts Victor kimberlite pipe (South Africa) have been measured by solution multi-collector ICP-MS. The reconstructed whole-rock ?26Mg values of Type I (metasomatized) eclogites range from ? 0.61‰ to ? 0.20‰ (Type IA) and from ? 0.60‰ to ? 0.30‰ (Type IB) (mean ? 0.43‰ ± 0.12‰), while ?26Mg of Type IIA (fresh, least metasomatized) eclogites ranges from ? 1.09‰ to ? 0.17‰ (mean ? 0.69‰ ± 0.41‰); a Type IIB (fresh, least metasomatized) has ?26Mg of ? 0.37‰. Oxygen-isotope compositions of garnet were analyzed in situ by SIMS (CAMECA 1280) and cross-checked by laser fluorination. Garnets have ?18O of 6.53‰ to 9.08‰ in Type IA, 6.14‰ to 6.65‰ in Type IB, and 2.34‰ to 2.91‰ in Type IIB. The variation of ?26Mg and ?18O in Type IA and IB eclogites is consistent with the previously proposed model for the evolution of these samples, based on major and trace elements and radiogenic isotopes. In this model, the protoliths (Type II eclogites) were metasomatized by carbonatitic to kimberlitic melts/fluids to produce first Type IA eclogites and then Type IB. Metasomatism has changed the O-isotope compositions, but the Mg-isotope compositions of Type IA are mainly controlled by the protoliths; those of Type IB eclogites reflect mixing between the protoliths and the kimberlitic melt/fluid. The combination of a large range of ?26Mg and low ?18O in Type II eclogites cannot be explained easily by seawater alteration of oceanic crust, interaction of carbonate/silicate sediments with oceanic crust, or partial melting of mafic rocks.
DS201702-0254
2017
Greau, Y.Xu, B., Griffin, W.L., Xiong, Q., Hou, Z-Q, O'Reilly, S.Y., Guo, Z., Pearson, N.J., Greau, Y., Yang, Z-M., Zheng, Y-C.Ultrapotassic rocks and xenoliths from South Tibet: contrasting styles of interaction between lithospheric mantle and asthenosphere during continental collision.Geology, Vol. 45, 1, pp. 51-54.China, TibetUPR - metasomatism

Abstract: Widespread Miocene (24-8 Ma) ultrapotassic rocks and their entrained xenoliths provide information on the composition, structure, and thermal state of the sub-continental lithospheric mantle in southern Tibet during the India-Asia continental collision. The ultrapotassic rocks along the Lhasa block delineate two distinct lithospheric domains with different histories of depletion and enrichment. The eastern ultrapotassic rocks (89°E-92°E) reveal a depleted, young, and fertile lithospheric mantle (87Sr/86Srt = 0.704-0.707 [t is eruption time]; Hf depleted-mantle model age [TDM] = 377-653 Ma). The western ultrapotassic rocks (79°E-89°E) and their peridotite xenoliths (81°E) reflect a refractory harzburgitic mantle refertilized by ancient metasomatism (lavas: 87Sr/86Srt = 0.714-0.734; peridotites: 87Sr/86Srt = 0.709-0.716). These data integrated with seismic tomography suggest that upwelling asthenosphere was diverted away from the deep continental root beneath the western Lhasa block, but rose to shallower depths beneath a thinner lithosphere in the eastern part. Heating of the lithospheric mantle by the rising asthenosphere ultimately generated the ultrapotassic rocks with regionally distinct geochemical signatures reflecting the different nature of the lithospheric mantle.
DS201906-1293
2019
Greau, Y.Gain, S.E.M., Greau, Y., Henry, H., Belousova, E., Dainis, I., Griffin, W.L., O'Reilly, S.Y.Mud Tank zircon: long term evaluation of a reference material for U-Pb dating, Hf-isotope analysis and trace element analysis. ( Carbonatite)Geostandards and Geoanalytical Research, in press available, 16p.Australiadeposit - Mud Tank

Abstract: Zircon megacrysts from the Mud Tank carbonatite, Australia, are being used in many laboratories as a reference material for LA?ICP?MS U?Pb dating and trace element measurement, and LA?MC?ICP?MS determination of Hf isotopes. We summarise a database of > 10000 analyses of Mud Tank zircon (MTZ), collected from 2000 to 2018 during its use as a secondary reference material for simultaneous U?Pb and trace element analysis, and for Hf?isotope analysis. Trace element mass fractions are highest in dark red?brown stones and lowest in colourless and gem?quality ones. Individual unzoned grains can be chemically homogeneous, while significant variations in trace element mass fraction are associated with oscillatory zoning. Chondrite?normalised trace element patterns are essentially parallel over large mass fraction ranges. A Concordia age of 731.0 ± 0.2 Ma (2s, n = 2272) is taken as the age of crystallisation. Some grains show lower concordant to mildly discordant ages, probably reflecting minor Pb loss associated with cooling and the Alice Springs Orogeny (450-300 Ma). Our weighted mean 176Hf/177Hf is 0.282523 ± 10 (2s, n = 9350); the uncertainties on this ratio reflect some heterogeneity, mainly between grains. A few analyses suggest that colourless grains have generally lower 176Hf/177Hf. MTZ is a useful secondary reference material for U?Pb and Hf?isotope analysis, but individual grains need to be carefully selected using CL imaging and tested for homogeneity, and ideally should be standardised by solution analysis.
DS202203-0336
2022
Greau, Y.Boone, S.C., Dalton, H., Prent, A., Kohlman, F., Theile, M., Greau, Y., Florin, G., Noble, W., Hodgekiss, S-A., Ware, B., Phillips, D., Kohn, B., O'Reilly, S., Gleadow, A., McInnes, B., Rawling, T.AusGeochem: an open platform for geochemical data preservation, dissemination and synthesis. Lithodat Pty *** not specific to diamonds but excellent concept/platformGeostandards and Geoanalysis Research, doi.org/10.1111/GGR.12419 34p. PdfAustraliageochemistry

Abstract: To promote a more efficient and transparent geochemistry data ecosystem, a consortium of Australian university research laboratories called the AuScope Geochemistry Network (AGN) assembled to build a collaborative platform for the express purpose of preserving, disseminating, and collating geochronology and isotopic data. In partnership with geoscience-data-solutions company Lithodat Pty Ltd, the open, cloud-based AusGeochem platform (https://ausgeochem.auscope.org.au) was developed to simultaneously serve as a geosample registry, a geochemical data repository, and a data analysis tool. Informed by method-specific groups of geochemistry experts and established international data reporting practices, community-agreed database schemas were developed for rock and mineral geosample metadata and secondary ion mass spectrometry U-Pb analysis, with additional models for laser ablation inductively-coupled mass spectrometry U-Pb and Lu-Hf, Ar-Ar, fission-track and (U-Th-Sm)/He under development. Collectively, the AusGeochem platform provides the geochemistry community with a new, dynamic resource to help facilitate FAIR (Findable, Accessible, Interoperable, Reusable) data management, streamline data dissemination and advanced quantitative investigations of Earth system processes. By systematically archiving detailed geochemical (meta-)data in structured schemas, intractably large datasets comprising thousands of analyses produced by numerous laboratories can be readily interrogated in novel and powerful ways. These include rapid derivation of inter-data relationships, facilitating on-the-fly data compilation, analysis, and visualisation.
DS200712-0353
2006
Greaux, S.Gautron, L., Greaux, S., Andrault, D., Bolfan Casanova, N., Guignot,N., Bouhifd, M.A.Uranium in the Earth's lower mantle.Geophysical Research Letters, Vol. 33, 23, Dec. 16, L23301MantleUranium
DS201612-2304
2016
Greaux, S.Ichikawa, H., Greaux, S., Azuma, S.Subduction of the primordial crust into the deep mantle.Geoscience Frontiers, in press availableMantleSubduction

Abstract: The primordial crust on the Earth formed from the crystallization of the surface magma ocean during the Hadean. However, geological surveys have found no evidence of rocks dating back to more than 4 Ga on the Earth's surface, suggesting the Hadean crust was lost due to some processes. We investigated the subduction of one of the possible candidates for the primordial crust, anorthosite and KREEP crust similar to the Moon, which is also considered to have formed from the crystallization of the magma ocean. Similar to the present Earth, the subduction of primordial crust by subduction erosion is expected to be an effective way of eliminating primordial crust from the surface. In this study, the subduction rate of the primordial crust via subduction channels is evaluated by numerical simulations. The subduction channels are located between the subducting slab and the mantle wedge and are comprised of primordial crust materials supplied mainly by subduction erosion. We have found that primordial anorthosite and KREEP crust of up to ?50 km thick at the Earth's surface was able to be conveyed to the deep mantle within 0.1-2 Gy by that mechanism.
DS201701-0020
2016
Greaux, S.Liu, Z., Du, W., Shinmei, T., Greaux, S., Zhou, C., Arimoto, T., Kunimoto, T., Irifune, T.Garnets in the majorite pyrope system: symmetry, lattice microstain, and order-disorder of cations.Physics and Chemistry of Minerals, in press available 9p.TechnologyGarnet morphology

Abstract: We present a systematic experimental study on the phase transition, lattice microstrain, and order-disorder of cations for garnets in the majorite-pyrope system. Polycrystalline gem-quality garnets were synthesized at high pressure and high temperature using a Kawai-type multi-anvil apparatus. A phase transition from a cubic to tetragonal structure is clearly observed for garnets with the majorite content of more than 74 mol % through X-ray diffraction (XRD) and Raman scattering studies. Microstrain of garnets, evaluated with the Williamson-Hall plot on XRD profiles, shows a nonlinear dependence of the garnet compositions. The variation of the XRD peak broadening suggests the lattice microstrain of these garnets may be associated with the local structural heterogeneities due to the substitution of different cations via the coupled substitution (Mg2+ + Si4+ = 2Al3+) in the garnet structure. The width variation of Raman scattering peaks indicates that cation disorder occurs in the garnet structure for intermediate compositions. It is found that intermediate garnets and end-members have a minimum of microstrain, while those between end-members and intermediate compositions possess a larger microstrain.
DS201709-2059
2017
Greaux, S.Stagno, V., Kono, Y., Greaux, S., Kebukawa, Y., Stopponi, V., Scarlato, P., Lustrino, M., Irifune, T.From carbon in meteorites to carbonatite rocks on Earth.Goldschmidt Conference, abstract 1p.Globalcarbonatite

Abstract: The composition of the early Earth’s atmosphere is believed to result from significant magma outgassing during the Archaean eon. It has been widely debated whether the oxygen fugacity (fo2) of the Earth’s mantle has remained constant over the last ~3.8 Ga to levels where volatiles were mostly in their mobile form [1,2], or whether the mantle has experienced a gradual increase of its redox state [3]. Both hypotheses raise fundamental questions on the effect of composition of the early Earth’s accreting material, the origin and availability of primordial carbon in Earth’s interior, and the migration rate of CO2-rich magmas. In addition, the occurrence in nature of carbonatites (or silicate-carbonatitic rocks), diamonds and carbides indicate a dominant control of the mantle redox state on the volatile speciation over time and, maybe, on mechanisms of their formation, reaction and migration through the silicate mantle. A recent model has been developed that combines both experimental results on the fo2 of preserved carbonaceous chondrites at high pressure and thermodynamic predictions of the the temporal variation of the mantle redox state, with the CO2-bearing magmas that could form in the early asthenospheric mantle. Since any variation in melt composition is expected to cause significant changes in the physical properties (e.g., viscosity and density), the migration rate of these magmas has been determined using recent in situ viscosity data on CO2-rich melts with the falling sphere technique. Our results allow determining the composition of CO2- bearing magmas as function of the increasing mantle redox state over time, and the mechanisms and rate for exchange of carbon between mantle reservoirs.
DS201903-0513
2018
Greaux, S.Greaux, S., Yamada, A.Density variations of Cr-rich garnets in the upper mantle inferred from the elasticity of uvarovite garnet.Comptes Rendu Geoscience, doi.org/10.16/ j.crte.2018.09.012 9p.MantleUHP

Abstract: The thermoelastic parameters of Ca3Cr2Si3O12 uvarovite garnet were examined in situ at high pressure up to 13 GPa and high temperature up to 1100 K by synchrotron radiation energy-dispersive X-ray diffraction within a 6-6-type multi-anvil press apparatus. A least-square fitting of room T data to a third-order Birch-Murnaghan (BM3) EoS yielded K0 = 164.2 ± 0.7 GPa, V0 = 1735.9 ± 0.3 Å3 (K’0 fixed to 4.0). P-V-T data were fitted simultaneously by a modified HT-BM3 EoS, which gave the isothermal bulk modulus K0 = 163.6 ± 2.6 GPa, K’0 = 4.1 ± 0.5, its temperature derivative (?K0,T/?T)P = -0.014 ± 0.002 GPa K?1, and the thermal expansion coefficients a0 = 2.32 ± 0.13 ×10?5 K?1 and b0 = 2.13 ± 2.18 ×10?9 K?2 (K’0 fixed to 4.0). Our results showed that the Cr3+ enrichment in natural systems likely increases the density of ugrandite garnets, resulting in a substantial increase of mantle garnet densities in regions where Cr-rich spinel releases chromium through a metasomatic reaction.
DS201905-1035
2019
Greaux, S.Greaux, S., Yamada, A.Density variations of Cr-rich garnets in the upper mantle inferred from the elasticity of uvarovite garnet.Comptes Rendus Geoscience, in press available 9p.Mantlegarnets

Abstract: The thermoelastic parameters of Ca3Cr2Si3O12 uvarovite garnet were examined in situ at high pressure up to 13 GPa and high temperature up to 1100 K by synchrotron radiation energy-dispersive X-ray diffraction within a 6-6-type multi-anvil press apparatus. A least-square fitting of room T data to a third-order Birch-Murnaghan (BM3) EoS yielded K0 = 164.2 ± 0.7 GPa, V0 = 1735.9 ± 0.3 Å3 (K’0 fixed to 4.0). P-V-T data were fitted simultaneously by a modified HT-BM3 EoS, which gave the isothermal bulk modulus K0 = 163.6 ± 2.6 GPa, K’0 = 4.1 ± 0.5, its temperature derivative (?K0,T/?T)P = -0.014 ± 0.002 GPa K?1, and the thermal expansion coefficients a0 = 2.32 ± 0.13 ×10?5 K?1 and b0 = 2.13 ± 2.18 ×10?9 K?2 (K’0 fixed to 4.0). Our results showed that the Cr3+ enrichment in natural systems likely increases the density of ugrandite garnets, resulting in a substantial increase of mantle garnet densities in regions where Cr-rich spinel releases chromium through a metasomatic reaction.
DS201908-1788
2019
Greaux, S.Liu, Z., Greaux, S., Cai, N., Siersch, N., Boffa Ballaran, T., Irifune, T., Frost, D.J.Influence of aluminum on the elasticity of majorite pyrope garnets.American Mineralogist, Vol. 104, pp. 929-935.Mantlegarnets

Abstract: The effect of aluminum (Al) on the elasticity of majorite-pyrope garnets was investigated by means of ultrasonic interferometry measurements on well-fabricated polycrystalline specimens. Both velocities and elastic moduli increase almost linearly with increasing Al content within analytical uncertainty. No significant variation of the velocities and elastic moduli is observed across the tetragonal-to-cubic phase transition at majorite with the pyrope content up to 26 mol% along the majorite-pyrope system. The elasticity variation of majorite-pyrope garnets is largely dominated by the Al content, while the phase transition as a result of cation ordering/disordering of Mg and Si via substitution of Al on octahedral sites cannot significantly affect elastic properties. Seismic velocity variations of a garnet-bearing mantle transition zone are therefore dominated by garnet composition (e.g., Al, Fe, Ca, and Na) rather than the tetragonal-to-cubic phase transition because of cation ordering/disordering.
DS202111-1792
2021
Greaux, S.Xu, C., Kakizawa, S., Greaux, S., Inoue, T., Li, Y., Gao, J.Al partitioning between phase D and bridgmanite at the uppermost lower mantle.Physics and Chemistry of Minerals, Vol. 48, 10, 6p. Pdf s00269-021-Q1163-5Mantlebridgmanite

Abstract: Phase D is proposed to be the most important hydrous phase at the upper part of the lower mantle, and it has been shown to coexist with bridgmanite (Brg), the most abundant mineral and main host for Al2O3 in the lower mantle. The concentration of Al in Phase D could significantly increase the thermal stability field of Phase D, therefore, partitioning of Al between Brg and Phase D is of particular importance to constrain water distribution in the deep mantle. Here, we performed high P-T experiments in MgO-Al2O3-SiO2-H2O system to investigate the partitioning of Al between Brg and Phase D up to 32 GPa and 1350 °C. Our results indicated that Al distributes strongly into Phase D relative to Brg and the partition coefficient slightly decreases with increasing temperature. Al-bearing Phase D exhibits a very high thermal stability region, but it completely decomposed around 28 GPa and 1350 °C, at which point Brg coexisted with a large amount of melt. The depth?~?850 km (28 GPa) is thus proposed to be the second choke point for hydrous minerals. This may shed new lights on several important geophysical observations in subduction zones.
DS201808-1748
2018
Greaves, J.S.Greaves, J.S., Scaife, A.M.M., Frayer, D.T., Green, D.A., Mason, B.S., Smith, A.M.S.Anomalous microwave emission from spinning nanodiamonds around stars.Nature Astronomy, doi.org/10.1038/s41550-018-0495-zGlobalnanodiamonds

Abstract: Several interstellar environments produce 'anomalous microwave emission', with brightness-peaks at tens-of-gigahertz frequencies. The emission's origins are uncertain - rapidly-spinning nano-particles could emit electric-dipole radiation, but polycyclic aromatic hydrocarbons proposed as the carrier are now found not to correlate with Galactic signals. The difficulty is to identify co-spatial sources over long lines of sight. Here we identify anomalous microwave emission in three proto-planetary discs. These are the only known systems that host hydrogenated nano-diamonds, in contrast to very common detection of polycyclic aromatic hydrocarbons. Spectroscopy locates the nano-diamonds close to the host-stars, at physically-constrained temperatures. Developing disc models, we reproduce the emission with diamonds 0.75-1.1 nanometres in radius, holding less than or equal to 1-2 per cent of the carbon budget. The microwave-emission:stellar-luminosity ratios are approximately constant, allowing nano-diamonds to be ubiquitous but emitting below detection thresholds in many star-systems. This can unify the findings with similar-sized diamonds found within solar system meteorites. As nano-diamond spectral absorption is seen in interstellar sightlines, these particles are also a candidate for generating galaxy-scale anomalous microwave emission.
DS1989-0534
1989
Greb, S.F.Greb, S.F.Structural controls on the formation of the sub-Absaroka unconformity In the U.S. Eastern interior basinGeology, Vol. 17, No. 10, October pp. 889-892KentuckyMidcontinent -structure, tectonics, Reelfoot rift
DS200512-0987
2004
GrebenshchikovaSimakov, S.K., Kalmykov, A.E., Sorokin, L.M., Novikov, Drozdova, Yagovkina, GrebenshchikovaChaoite formation from carbon bearing fluid at low PT parameters.Doklady Earth Sciences, Vol. 399A, 9, Nov-Dec. pp. 1289-1290.Mineralogy - chaoite
DS200412-1826
2004
Grebenshchikova, E.Simakov, S., Kalmykov, A., Sorokin, L., Grebenshchikova, E.Chaoite synthesis at lower temperatures and pressures.Lithos, ABSTRACTS only, Vol. 73, p. S102. abstractTechnologyDiamond like carbon phase
DS201710-2229
2017
Greber, N.Greber, N.Plate tectonics started at least 3.5 billion years ago.Science News, Sept. 21, 1p.Mantletitanium, Plate Tectonics

Abstract: Plate tectonics may have gotten a pretty early start in Earth’s history. Most estimates put the onset of when the large plates that make up the planet’s outer crust began shifting at around 3 billion years ago. But a new study in the Sept. 22 Science that analyzes titanium in continental rocks asserts that plate tectonics began 500 million years earlier. Nicolas Greber, now at the University of Geneva, and colleagues suggest that previous studies got it wrong because researchers relied on chemical analyses of silicon dioxide in shales, sedimentary rocks that bear the detritus of a variety of continental rocks. These rocks’ silicon dioxide composition can give researchers an idea of when continental rocks began to diverge in makeup from oceanic rocks as a result of plate tectonics.But weathering can wreak havoc on the chemical makeup of shales. To get around that problem, Greber’s team turned to a new tool: the ratios of two titanium isotopes, forms of the same element that have different masses. The proportion of titanium isotopes in the rocks is a useful stand-in for the difference in silicon dioxide concentration between continental and oceanic rocks, and isn’t so easily altered by weathering. Those data helped the team estimate that continental rocks — and therefore plate tectonics — were already going strong by 3.5 billion years ago.
DS201802-0252
2017
Grechanovskii, A.E.Marchenko, E.I., Eremin, N.N., Bychkov, A.Y., Grechanovskii, A.E.Ca and Mg perovskite phases in the Earth's mantle as a probable reservoir of Al: computer simulated evidence.Moscow University Geology Bulletin, Vol. 72, 5, pp. 299-304.Mantleperovskite

Abstract: Semi-empirical and quantum chemical studies of Al atom energy in CaSiO3 and MgSiO3 with the perovskite-type structure at pressures and temperatures of the Earth’s mantle are reported. The phase diagram for CaSiO3 is reproduced and refined. Probable mechanisms of Al incorporation in the structures studied are considered. According to the results of the calculations, Al is preferably incorporated into MgSiO3, rather than into CaSiO3. Evaluation of the isomorphic capacity of perovskite phases in relation to Al shows that the Al content in MgSiO3 may reach 2.4 mol % at 120 GPa and 2400 K. CaSiO3 cannot be a source of Al atoms in the Earth’s mantle.
DS1997-0441
1997
Grecoe, T.Grecoe, T.Warming signals in the Mackenzie Basin.... climate hot spotCan. Geographic, Vol. 117, No. 6, Nov-Dec . pp. 36-44Northwest TerritoriesGeomorphology, Mackenzie Basin
DS1996-0561
1996
Grecula, P.Grecula, P.Mineral deposits of the Slovak ore MountainsSlovak Geological Survey, Vol. 1, 900p. approx. $ 65.00 United StatesGlobalGeology, metallogeny, mineralization, Table of contents
DS200812-0504
2008
Gree, D.H.Irving, A.J., Gree, D.H.Phase relationships of hydrous alkalic magmas at high pressures: production of nepheline hawaiitic to mugearitic liquids by amphibole dominated fractionalJournal of Petrology, Vol. 49, 4, pp. 741-756.MantleNephelinite
DS1960-0953
1968
Greef, G.J.Greef, G.J.Fracture Systems and the Kimberlite Intrusions of Griqualand West.Stellenbosch: Msc. Thesis, University Stellenbosch, South AfricaTectonics, Lineament Analyses
DS1981-0186
1981
Greeman, T.K.Greeman, T.K.Lineaments and Fracture Traces, Jennings County and Jefferson Proving Ground Indiana.United States Geological Survey (USGS) OPEN FILE., No. 81-1120.GlobalMid-continent, Tectonic
DS1992-0710
1992
GreenHinze, W.J., Allen, D.J., Fox, A.J., Sunwood, D., Woelk, T., GreenGeophysical investigations and crustal of the North American Midcontinent rift systemTectonophysics, Vol. 213, No. 1-2, special issue, pp. 17-32MidcontinentTectonics, Geophysics
DS1992-0744
1992
GreenHutchinson, D.R., Lee, M.W., Behrendt, J., Cannon, W.F., GreenVariations in the reflectivity of the Moho transition zone beneath The midcontinent Rift System of North America. Results from true amplitude GlimpcedataJournal of Geophysical Research, Vol. 97, No. B4, April 10, pp. 4721-4738MidcontinentGeophysics -seismics, Tectonics
DS2001-0737
2001
GreenMateev, S., O'Neill, H. St., Ballhaus, Taylor, GreenEffect of silica activity on OH IR spectra of olivine: implications for low aSiO2 mantle Metasomatism..Journal of Petrology, Vol. 42, No. 4, Apr. pp. 721-30.MantleMetasomatism - silica
DS2002-0484
2002
GreenFriberg, M., Juhlin, Beckolmen, Petrov, GreenPaleozoic tectonic evolution of the Middle Urals in the light of ESRU seismic experiment.Journal of the Geological Society of London, Vol.159,3,pp.295-306., Vol.159,3,pp.295-306.Russia, UralsTectonics
DS2002-0485
2002
GreenFriberg, M., Juhlin, Beckolmen, Petrov, GreenPaleozoic tectonic evolution of the Middle Urals in the light of ESRU seismic experiment.Journal of the Geological Society of London, Vol.159,3,pp.295-306., Vol.159,3,pp.295-306.Russia, UralsTectonics
DS1987-0042
1987
Green, A.Behrendt, J.C., Green, A., Cannon, W.F.Crustal attentuation and associated basalt flow extrusion in the Keweenawanrift, Lake Superior from deep seismic reflectionprofilesGeological Society of America, Vol. 19, No. 7 annual meeting abstracts, p. 585. abstraGlobalTectonics
DS1989-0208
1989
Green, A.Cannon, W.F., Nicholson, S.W., Green, A.Tectonic and magmatic development of the Midcontinentrift: a synthesis of new seismic ,chemical and isotopic dataUnited Stated Geological Survey (USGS) Circular 1035, Fifth Annual V.E. McKelvey Forum, held Reno, pp. 7-8. Abstract onlyMidcontinent, Kansas, Michigan, Lake Superior regionTectonics, rift model
DS1989-1441
1989
Green, A.Spencer, C., Green, A., Morel-a-l'Huissier, P.The extension of the Grenville basement beneath the northern Appalachians:results from the Quebec-Maine seismic reflection and refraction surveysTectonics, Vol. 8, No. 4, August pp. 677-696GlobalGeophysics-Seismics, Tectonics
DS1993-0930
1993
Green, A.Lucas, S.B., Green, A., et al.Deep seismic profile across a Proterozoic collision zone: surprises atdepthNature, Vol. 363, No. 6427, May 27, pp. 339-341GlobalGeophysics -seismics, Tectonics
DS1994-1033
1994
Green, A.Lewry, J.F., Hajnal, Z., Green, A., et al.Structure of a Paleoproterozoic continent-continent collision zone: a Lithoprobe seismic reflection profileTectonophysics, Vol. 232, pp. 143-160SaskatchewanGeophysics -seismics, lithoprobe, Orogen -Trans Hudson
DS1990-1064
1990
Green, A. G.Morel-a-l'hussier, P., Green, A. G., Jones, A.G., Latham, T.The crust beneath the intracratonic Williston Basin from geophysical datain: Pinet, B., Bois, C. editors The potential of deep seismic profiling for, pp. 141-160SaskatchewanGeophysics, Williston Basin
DS1980-0146
1980
Green, A.G.Green, A.G., Stephenson, O.G.Cooperative Seismic Surveys Across the Superior- Churchill Boundary Zone in Southern Canada.Canadian Journal of Earth Sciences, Vol. 17, PP. 617-632.GlobalMid-continent, Geophysics
DS1983-0261
1983
Green, A.G.Green, A.G., Clowes, R.M.Deep Geology from Seismic Reflection Studies in CanadaFirst Break, Vol. 1, No. 7, PP. 24-33.Canada, Manitoba, OntarioGeophysics
DS1985-0246
1985
Green, A.G.Green, A.G., et al.Evolution of Proterozoic Terrains Beneath the Williston BasinGeology, Vol. 13, pp. 624-8.SaskatchewanBasin, Craton
DS1985-0247
1985
Green, A.G.Green, A.G., Hajnal, WeberAn evolutionary model of the Western Churchill Province and western Margin of the Superior province in canada.Tectonophysics, Vol. 116, pp. 281-322.Saskatchewan, Manitoba, MontanaGeophysics - Seismics, Magnetics, North American Central Plains Anomaly
DS1987-0490
1987
Green, A.G.Morel -A-Lhuissier, P., Green, A.G., Pike, C.J.Crustal refraction surveys across the Trans Hudson orogen/Williston Basin of South Central CanadaJournal of Geophysical Research, Vol. 92, No. B7, June 10, pp. 6403-6420CanadaSaskatchewan, Geophysics
DS1988-0048
1988
Green, A.G.Behrendt, J.C., Green, A.G., Cannon, W.F., Hutchinson, D.R., LeeCrustal structure of the Midcontinent rift system: results from GLIMPCE deep seismic reflection profilesGeology, Vol. 16, No. 1, January pp. 81-85GlobalTectonics, GLIMPCE.
DS1989-0207
1989
Green, A.G.Cannon, W.F., Green, A.G., Hutchinson, D.R., Myung Lee, MilkereitThe North American Midcontinent rift beneath Lake superior from GLIMPCE seismic reflection profilingTectonics, Vol. 8, No. 2, April pp. 305-332MidcontinentGeophysics, Glimpce
DS1989-0209
1989
Green, A.G.Cannon, W.F., Schulz, K.J., Hinze, W.J., Green, A.G.Precambrian terranes beneath northern Lake Michigan defined by seismic and gravity analysis35th. Annual Institute On Lake Superior Geology, Proceedings And, pp. 14-15MichiganMidcontinent, Seismics, Geophysics, Tect
DS1989-0535
1989
Green, A.G.Green, A.G., Cook, F.A., Milkereit, B.Lithoprobe seismic reflection profiles from the south- eastern CanadianCordilleraG.s.c. Open File, No. 2130, 13p. 12 sheets $ 27.00CordilleraGeophysics -seismics, Lithoprobe
DS1989-0536
1989
Green, A.G.Green, A.G., Milkereit, B., Davidson, A., Percival, J.A., ParrishReflection seismic profiling of the Kapuskasing structural zone, SOURCE[ Geological Association of Canada (GAC) Annual Meeting Program AbstractsGeological Society of Canada (GSC) Forum 1989, P. 11. abstractOntarioMidcontinent, Kapuskasing structure
DS1989-0537
1989
Green, A.G.Green, A.G., Milkereit, B., Percival, J.A., Kurtz, R.D., BroomeIntegrated geophysical lithoprobe studies of the Kapuskasing structureGeological Society of Canada (GSC) Forum 1989, P. 11. abstractOntarioGeophysics, Kapuskasing
DS1989-0903
1989
Green, A.G.Ludden, J.N., Hubert, C., Mayrand, L.J., Milkereit, B., Green, A.G.Results from the lithoprobe Abitibi projectGeological Society of Canada (GSC) Forum 1989, P. 17 abstractOntarioGeophysics-seismics
DS1989-1022
1989
Green, A.G.Milkereit, B., Green, A.G., Cook, F.A., West, G.F.Lithoprobe seismic profiles across the Kapuskasingstructure, northernOntarioG.s.c. Open File, No. 2131, 16p. 21 sheets $ 30.50Ontario, MidcontinentGeophysics, Lithoprobe, Kapuskasing structure
DS1989-1197
1989
Green, A.G.Percival, J.A., Green, A.G.Lithoprobe studies of the Kapuskasing uplift: an exposed crustal crosssectionGeological Society of Canada (GSC) Forum 1989, P. 19 abstractOntarioMidcontinent
DS1989-1198
1989
Green, A.G.Percival, J.A., Green, A.G., Milkereit, B., Cook, F.A., Geis, W.Seismic reflection profiles across deep continental crust exposed in the Kapuskasing uplift structureNature, Vol. 342, No. 6248, November 23, pp. 416-419OntarioGeophysics -seismic, Kapuskasing rift zone
DS1989-1605
1989
Green, A.G.West, G.F., Harley, P., Green, A.G., Milkereit, B., Cook, F., GeisReflection seismic profiling of the Kapuskasing structural zoneGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A124. (abstract.)OntarioTectonics, Kapuskasing Zone
DS1990-0271
1990
Green, A.G.Cannon, W.F., Phillips, J.D., Green, A.G., Morel-a l'Hussier, P.Great Lakes segment of the Canada -U.S. border transectGeological Society of America (GSA) Annual Meeting, Abstracts, Vol. 22, No. 7, p. A191GlobalGeochronology, Crust
DS1990-0527
1990
Green, A.G.Geis, W.T., Cook, F.A., Green, A.G., Milkereit, B., Percival, J.A.Thin thrust sheet formation of the Kapuskasing structural zone revealed bylithoprobe seismic reflection dataGeology, Vol. 18, No. 6, June pp. 513-516OntarioGeophysics -Seismics, Kapuskasing Zone
DS1990-0528
1990
Green, A.G.Geis, W.T., Cook, F.A., Green, A.G., Milkereit, B., Percival, J.A.Thin thrust sheet formation of the Kapuskasing structural zone revealed by lithoprobe seismic reflection dataGeology, Vol. 18, No. 6, June pp. 513-516OntarioGeophysics, Kapuskasing Zone
DS1990-0596
1990
Green, A.G.Green, A.G., et al.Origin of deep crustal reflections: seismic profiling across high grade metamorphic terranes in Canada.Tectonophysics, Vol. 173, pp. 627-38.Ontario, British ColumbiaGeophysics - seismics, Lithoprobe
DS1990-0597
1990
Green, A.G.Green, A.G., Milkereit, B.Diverse seismic reflection images from the Canadian shieldTerra, Abstracts of Deep Seismic reflection profiling of the Continental, Vol. 2, December abstracts p. 163OntarioKapuskasing, Tectonics
DS1990-0598
1990
Green, A.G.Green, A.G., Milkereit, B., Mayrand, L.J., Ludden, J.N., Hubert, C.Deep structure of an Archean greenstone terraneNature, Vol. 344, No. 6164, March 22, pp. 327-329QuebecGreenstone belt, Tectonics/structure
DS1990-1043
1990
Green, A.G.Milkereit, B., Green, A.G., Lee, M.W., Agena, W.F., Spencer, C.Pre- and post stack migration of Glimpce reflection dataTectonophysics, Vol. 174, No. 1/2, March 1, pp. 1-14Ontario, MichiganGeophysics -Seismics, Glimpce
DS1991-0217
1991
Green, A.G.Cannon, W.F., Lee, M.Y.W., Hinze, W.J., Schulz, K.J., Green, A.G.Deep crustal structure of the Precambrian basement beneath northern LakeMichigan, midcontinent North AmericaGeology, Vol. 19, No. 3, March pp. 207-210MichiganTectonics, Structure -crustal
DS1991-0969
1991
Green, A.G.Leclair, A.D., Percival, J.A., Milkereit, B., Green, A.G., West G.F.Seismic reflection profiles across major faults of the central KapuskasingUpliftGeological Association of Canada (GAC)/Mineralogical Association of Canada/Society Economic, Vol. 16, Abstract program p. A73OntarioTectonics, Geophysics -seismics
DS1991-1154
1991
Green, A.G.Milkereit, B., Percival, J.A., White, D., Green, A.G., SalisburySeismic reflectors in high grade metamorphic rocks of the Kapuskasinguplift: results of preliminary drill site surveysGeodynamics, Vol. 22, pp. 39-45OntarioKapuskasing uplift, Geophysics -seismics
DS1992-1063
1992
Green, A.G.Milkereit, B., Forsyth, D.A., Green, A.G., Davidson, A., Hanmer, S.Seismic images of a Grenvillian terrane boundaryGeology, Vol. 20, No. 11, November pp. 1027-1030OntarioGeophysics -seismics, Terrane
DS1994-1010
1994
Green, A.G.Leclair, A.D., Percival, J.A., Green, A.G., et al.Seismic reflection profiles across the central Kapuskasing upliftCanadian Journal of Earth Sciences, Vol. 31, No. 7, July pp. 1016-1026.OntarioGeophysics -seismics, Tectonics -Kapuskasing uplift
DS1994-1193
1994
Green, A.G.Milkereit, B., White, D.J., Green, A.G.Towards an improved seismic technique for crustal structures: the Lithoprobe Sudbury experimentGeophy. Res. Letters, Vol. 21, No. 10, May 15, pp. 927-930OntarioLithoprobe, Sudbury Structure
DS2000-0302
2000
Green, A.G.Friberg, M., Juhlin, C., Green, A.G., Hortsmeyer, RothEuroprobe seismic reflection profiling across the eastern middle Urals and West Siberian Basin.Terra Nova, Vol. 12, No. 6, Dec.pp. 252-7.Urals, Russia, SiberiaGeophysics - seismics
DS1860-0592
1888
Green, A.H.Green, A.H.A Contribution to the Geology and Physical Geography of The cape Colony.Quarterly Journal of Geological Society (London), Vol. 44, PP. 239-241.Africa, South Africa, Cape ProvinceRegional Geology
DS200512-0751
2004
Green, B.Moses, T.M., Johnson, M.L., Green, B., Blodgett, Cino, Geurts, Gilbertson, hemphill, King, Kornylak, ReinitzA foundation for grading the overall cut quality of round brilliant cut diamonds.Gems & Gemology, Vol. 40, 3, Fall, pp. 202-228.Diamond cutting
DS202004-0497
2020
Green, B.Ashfold, M.N.R., Goss, J.P., Green, B., May, P.W., Newton, M.E., Peaker, C.V.Nitrogen in diamond.Chemical Reviews, Vol. 120, 4, 10.1021/ acs.chemrev.9b00578 50p. PdfGlobalHPHT, CVD, synthetics

Abstract: Nitrogen is ubiquitous in both natural and laboratory-grown diamond, but the number and nature of the nitrogen-containing defects can have a profound effect on the diamond material and its properties. An ever-growing fraction of the supply of diamond appearing on the world market is now lab-grown. Here, we survey recent progress in two complementary diamond synthesis methods: high pressure high temperature (HPHT) growth and chemical vapor deposition (CVD), how each is allowing ever more precise control of nitrogen incorporation in the resulting diamond, and how the diamond produced by either method can be further processed (e.g., by implantation or annealing) to achieve a particular outcome or property. The burgeoning availability of diamond samples grown under well-defined conditions has also enabled huge advances in the characterization and understanding of nitrogen-containing defects in diamond alone and in association with vacancies, hydrogen, and transition metal atoms. Among these, the negatively charged nitrogen-vacancy (NV-) defect in diamond is attracting particular current interest in account of the many new and exciting opportunities it offers for, for example, quantum technologies, nanoscale magnetometry, and biosensing.
DS202004-0508
2020
Green, B.Diggle, P.L., Dhaenens-Johannsson, U., Green, B., Welbourn, C.M., Tran Thi, T.N., Wang, W., Newton, M.E. Decoration of growth sector boundaries with single nitrogen vacancy centres in as-grown single crystal HPHT synthetic diamond.Diamond and Related Materials, arxiv.org 21p. Globalsynthetics

Abstract: Large (> 100 mm3), relatively pure (type II) and low birefringence single crystal diamond can be produced by high pressure high temperature (HPHT) synthesis. In this study we examine a HPHT sample of good crystalline perfection, containing less than 1 ppb (part per billion carbon atoms) of boron impurity atoms in the {001} growth sector and only tens of ppb of nitrogen impurity atoms. It is shown that the boundaries between {111} and {113} growth sectors are decorated by negatively charged nitrogen vacancy centres (NV?): no decoration is observed at any other type of growth sector interface. This decoration can be used to calculated the relative {111} and {113} growth rates. The bulk (001) sector contains concentrations of luminescent point defects (excited with 488 and 532 nm wavelengths) below 1011 cm?3 (10?3 ppb). We observe the negatively charged silicon-vacancy (SiV?) defect in the bulk {111} sectors along with a zero phonon line emission associated with a nickel defect at 884 nm (1.40 eV). No preferential orientation is seen for either NV? or SiV? defects, but the nickel related defect is oriented with its trigonal axis along the <111> sector growth direction. Since the NV? defect is expected to readily re-orientate at HPHT diamond growth temperatures, no preferential orientation is expected for this defect but the lack of preferential orientation of SiV? in {111} sectors is not explained.
DS201901-0095
2018
Green, B.L.Zhao, J., Breeze, B.G., Green, B.L., Diggle, P.L., Newton, M.E.Fluorescence, phosphoresence, thermoluminesence, and charge tranfer in synthetic diamond.Gems & Gemology, Sixth International Gemological Symposium Vol. 54, 3, 1p. Abstract p. 266.GlobalFluoresence

Abstract: Photoluminescence (PL) and phosphorescence underpin many of the discrimination techniques used to separate natural from synthetic diamond. PL is at the heart of many new quantum technologies based on color centers in lab-grown diamonds. In HPHT synthetic diamond, the phosphorescence observed is explained in terms of donor-acceptor pair recombination. The thermal activation of electrons to neutral boron acceptors shows that boron plays a key role in the phosphorescence process. However, there are a number of things we struggle to explain. For example, the phosphorescence peak positions are not fully explained, and there is no conclusive link between the emission and charge transfer involving the substitutional nitrogen donor. Secondly, the origin of the phosphorescence observed in some synthetic diamond samples grown by the CVD process is unclear. Although we now have evidence for unintentional boron impurity incorporation at stop-start growth boundaries in some CVD syn- thetic samples, it is possible that some of the observed phosphorescence does not involve boron impurities. In this paper we report on the results of combined fluorescence, phosphorescence, thermoluminescence, and quantitative charge transfer investigations undertaken on both HPHT and CVD synthetic diamond, with the objective of identifying which defects are involved in the fluorescence and phosphorescence processes.
DS201809-2030
2018
Green, C.Green, C.The pursuit of colour. Part 1. The rise to prominence of fancy coloured diamonds post 1970.The Australian Gemmologist, Vol. 26, 9-10, pp. 226-239.Globaldiamond - colour
DS201911-2507
2019
Green, C.Akam, C., Simandl, G.J., Lett, R., Paradis, S., Hoshino, M., Kon, Y., Araoka, D., Green, C., Kodama, S., Takagi, T., Chaudhry, M.Comparison of methods for the geochemical determination of rare earth elements: Rock Canyon Creek REE-F-Ba deposit case study, SE British Columbia, Canada.Geochemistry: Exploration, Environment, Analysis, Vol. 19, pp. 414-430.Canada, British Columbiageochemistry

Abstract: Using Rock Canyon Creek REE-F-Ba deposit as an example, we demonstrate the need for verifying inherited geochemical data. Inherited La, Ce, Nd, and Sm data obtained by pressed pellet XRF, and La and Y data obtained by aqua regia digestion ICP-AES for 300 drill-core samples analysed in 2009 were compared to sample subsets reanalysed using lithium metaborate-tetraborate (LMB) fusion ICP-MS, Na2O2 fusion ICP-MS, and LMB fusion-XRF. We determine that LMB ICP-MS and Na2O2 ICP-MS accurately determined REE concentrations in SY-2 and SY-4, and provided precision within 10%. Fusion-XRF was precise for La and Nd at concentrations exceeding ten times the lower detection limit; however, accuracy was not established because REE concentrations in SY-4 were below the lower detection limit. Analysis of the sample subset revealed substantial discrepancies for Ce concentrations determined by pressed pellet XRF in comparison to other methods due to Ba interference. Samarium, present in lower concentrations than other REE compared, was underestimated by XRF methods relative to ICP-MS methods. This may be due to Sm concentrations approaching the lower detection limits of XRF methods, elemental interference, or inadequate background corrections. Aqua regia dissolution ICP-AES results, reporting for La and Y, are underestimated relative to other methods.
DS1960-0552
1965
Green, D.Green, D.Gemstones and Ornamental StonesGeological Survey Bechuanaland Protectorate, (UNPUBL.)BotswanaDiamond
DS1960-0674
1966
Green, D.Green, D.The Karroo System in BechuanalandBotswana Geological Survey, Bulletin. No. 2, 74P.BotswanaStratigraphy
DS1980-0147
1980
Green, D.Green, D., Crockett, R.N., Jones, M.T.Tectonic Control of Karroo Sedimentation in Mid-eastern Botswana.Geological Society of South Africa Transactions, Vol. 83, PP. 213-219.BotswanaRegional Tectonics
DS201808-1748
2018
Green, D.A.Greaves, J.S., Scaife, A.M.M., Frayer, D.T., Green, D.A., Mason, B.S., Smith, A.M.S.Anomalous microwave emission from spinning nanodiamonds around stars.Nature Astronomy, doi.org/10.1038/s41550-018-0495-zGlobalnanodiamonds

Abstract: Several interstellar environments produce 'anomalous microwave emission', with brightness-peaks at tens-of-gigahertz frequencies. The emission's origins are uncertain - rapidly-spinning nano-particles could emit electric-dipole radiation, but polycyclic aromatic hydrocarbons proposed as the carrier are now found not to correlate with Galactic signals. The difficulty is to identify co-spatial sources over long lines of sight. Here we identify anomalous microwave emission in three proto-planetary discs. These are the only known systems that host hydrogenated nano-diamonds, in contrast to very common detection of polycyclic aromatic hydrocarbons. Spectroscopy locates the nano-diamonds close to the host-stars, at physically-constrained temperatures. Developing disc models, we reproduce the emission with diamonds 0.75-1.1 nanometres in radius, holding less than or equal to 1-2 per cent of the carbon budget. The microwave-emission:stellar-luminosity ratios are approximately constant, allowing nano-diamonds to be ubiquitous but emitting below detection thresholds in many star-systems. This can unify the findings with similar-sized diamonds found within solar system meteorites. As nano-diamond spectral absorption is seen in interstellar sightlines, these particles are also a candidate for generating galaxy-scale anomalous microwave emission.
DS1960-0479
1964
Green, D.H.Mcdougall, I., Green, D.H.Excess Radiogenic Argon in Pyroxenes and Isotopic Ages on Minerals from Norwegian Eclogites.Norske Geol. Tidsskr., Vol. 44, PP. 183-196.Norway, ScandinaviaIsotope
DS1960-0735
1966
Green, D.H.Ringwood, A.E., Green, D.H.An Experimental Investigation of the Gabbro Eclogite Transformation and Some Geophysical Implications.Tectonophysics, Vol. 3, No. 5, PP. 383-427.South AfricaGeophysics, Eclogites
DS1960-1114
1969
Green, D.H.Green, D.H.Mineralogy of Norwegian EclogitesContrib. To Physico-chemical Petrology, (korhinskii Volume P, Vol. 1, PP. 37-44.Norway, ScandinaviaEclogite, Ultramafic And Related Rocks
DS1970-0519
1972
Green, D.H.Green, D.H.A Comparison of Recent Experimental Dat a on the Gabbro-garnet Granulite-eclogite Transition.Journal of GEOLOGY, Vol. 80, PP. 277-288.GlobalEclogite, Kimberlite
DS1975-0089
1975
Green, D.H.Green, D.H., Sobolev, N.V.Coexisting Garnets and Ilmenites Synthesized at High Pressure pressures from Pyrolite and Olivine Basanite and Their Significance for Kimberlitic Assemblages.Contributions to Mineralogy and Petrology, Vol. 50, PP. 217-229.South AfricaWesselton, Microprobe Analyses
DS1975-0296
1976
Green, D.H.Irving, A.J., Green, D.H.Geochemistry and Petrogenesis of the Newer Basalts of Victoria and South Australia.Geological Society AUST. Journal, Vol. 23, PP. 45-66.AustraliaKimberlite
DS1975-0746
1978
Green, D.H.Frey, F.A., Green, D.H., Roy, S.D.Integrated Models of Basalt Petrogenesis: a Study of QuartzJournal of PETROLOGY, Vol. 19, PP. 463-513.Australia, New South Wales, VictoriaBasalt, Related Rocks
DS1975-1009
1979
Green, D.H.Ellis, D.J., Green, D.H.An Experimental Study of the Effect of Calcium upon Garnet Clinopyroxene Iron - Magnesium Exchange Equilibria.Contributions to Mineralogy and Petrology, Vol. 71, PP. 13-22.GlobalMineral Chemistry, Analyses, Eclogite
DS1982-0248
1982
Green, D.H.Harley, S.L., Green, D.H.Garnet Ortho Pyroxene Barometry for Granulites and Peridotites.Nature., Vol. 300, No. 5894, PP. 697-701.AustraliaGenesis, Related Rocks
DS1982-0249
1982
Green, D.H.Harley, S.L., Green, D.H.garnet-orthopy roxene Barometry for Granulites and PeridotiteNature., Vol. 300, No. 5894, Dec. 23RD., PP. 697-701.GlobalBlank
DS1982-0461
1982
Green, D.H.Nickel, K.G., Green, D.H.Ultramafic Xenoliths from Lake Bulletinen Merri and Mt. Leura, South East Australia, and Their Bearing on the Evolution of The Continental Upper Mantle.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 230, (abstract.).AustraliaKimberlite, Chemistry
DS1984-0437
1984
Green, D.H.Kuehner, S.M., Green, D.H.Mafic Dikes from the Vestfold Hills, AntarcticaGeological Society of Australia., No. 12, ABSTRACT VOLUME PP. 314-316.GlobalGeochronology, Petrography
DS1984-0550
1984
Green, D.H.Nickel, K.G., Green, D.H.The Nature of the Upper Most Mantle Beneath Victoria Australia As Deduced from Ultramafic Xenoliths.Proceedings of Third International Kimberlite Conference, Vol. 2, PP. 161-178.Australia, Lake Bulletinenmerri, Mt. LeuraWehrlite, Mineral Chemistry, Microprobe Analyses
DS1985-0491
1985
Green, D.H.Nickel, K.G., Green, D.H.Empirical Geothermobarometry for Garnet Peridotites and Implications for the Nature of the Lithosphere, Kimberlites Anddiamonds.Earth Planet. Sci. Letters, Vol. 73, PP. 158-170.South Africa, Africa, Australia, CanadaModels, Genesis, Experimental, Geobarometry
DS1986-0249
1986
Green, D.H.Foley, S.F., Taylor, W.R., Green, D.H.The role of fluorine and oxygen fugacity in the genesis ofultrapotassicrocksContributions to Mineralogy and Petrology, Vol. 94, No. 2, pp. 183-192Wyoming, Spain, Arkansas, Utah, Germany, CaliforniaLamproite
DS1986-0301
1986
Green, D.H.Green, D.H., Falloon, T.J., Brey, G.P., Nickel, K.G.Peridotite melting to GPa and genesis of primary mantle derived magmasProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 181-183GlobalMantle
DS1986-0561
1986
Green, D.H.Mengel, K., Green, D.H.Experimental study of amphibole and phlogopite stability in metasomatized peridoite under water saturated and water undersaturated conditionsProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 193-195GlobalExperimental petrology
DS1986-0799
1986
Green, D.H.Taylor, W.R., Green, D.H.The role of reduced C-O-H fluids in mantle partial melting #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 211-213GlobalExperimental petrology
DS1987-0169
1987
Green, D.H.Duncan, R.A., Green, D.H.The geochemistry and petrology of an alkaline lamprophyre sheet intrusion complex on Maio Cape Verde RepublicContributions to Mineralogy and Petrology, Vol. 96, pp. 326-342GlobalMantle genesis, Peridotites
DS1987-0218
1987
Green, D.H.Foley, S.F., Venturello, G., Green, D.H., Toscani, L.The ultrapotassic rocks: characteristics, classification and constraints for petrogenetic modelsEarth Science Reviews, Vol.24, pp. 81-134GlobalClassification, Petrogenesis
DS1988-0266
1988
Green, D.H.Green, D.H., Wallace, M.E.Mantle metasomatism by ephemeral carbonatite meltsNature, Vol. 336, np. 6198, Dec. 1, pp. 459-462GlobalMantle, Carbonatite
DS1988-0687
1988
Green, D.H.Taylor, W.R., Green, D.H.Measurement oof reduced peridotite- C-O-H solidus And implications for redox melting of the mantleNature, Vol. 332, No. 6162, March 24, pp. 349-351GlobalBlank
DS1988-0746
1988
Green, D.H.Wallace, M.E., Green, D.H.An experimental determination of primary carbonatite magma compositionNature, Vol. 335, No. 6188, Sept. 22, pp. 343-346GlobalCarbonatite, Magma
DS1989-0307
1989
Green, D.H.Crawford, A.J., Falloon, T.J., Green, D.H.Classification, petrogenesis and tectonic setting of boninitesIn: Boninites, Editor A.J. Crawford, Unwin and Hyman, pp. 2-49GlobalBoninites, Classification
DS1989-0415
1989
Green, D.H.Falloon, T.J., Green, D.H.The solidus of carbonated, fertile peridotiteEarth and Planetary Science Letters, Vol. 94, No. 3/4 September pp. 364-370HawaiiPyrolite/peridotite, Experimental petrogenesis
DS1989-1005
1989
Green, D.H.Mengel, K., Green, D.H.Stability of amphibole and phlogopite in metasomatized peridotite underwater-saturated and water-undersaturated conditionsGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 1, pp. 571-581GlobalMantle Metasomatism, Experimental petrology
DS1989-1485
1989
Green, D.H.Taylor, W.R., Green, D.H.The role of reduced C-O-H fluids in mantle partial melting #2Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 1, pp. 592-602GlobalMantle, Oxidation
DS1990-0160
1990
Green, D.H.Ballhaus, C., Berry, R.F., Green, D.H.Oxygen fugacity controls in the earth's upper mantleNature, Vol. 348, No. 6300, November 29, pp. 437-439GlobalMantle, Geochronology -oxygen
DS1990-0462
1990
Green, D.H.Falloon, T.J., Green, D.H.Solidus of carbonated fertile peridotite under fluid-saturatedconditionsGeology, Vol. 18, No. 3, March pp. 193-288GlobalGeochemistry, Peridotite
DS1990-0599
1990
Green, D.H.Green, D.H.Fluids in subduction zones: experimental constraintsGeological Society of Australia Abstracts, No. 25, No. A12.11 pp. 213-214. AbstractGlobalExperimental petrology, Magma genesis
DS1990-0600
1990
Green, D.H.Green, D.H.The role of oxidation-reduction and C-H-O fluids in determining melting conditions and magma compositions in the Upper MantleProceedings Indian Academy of Sciences, Vol. 99, No. 1, March pp. 153-GlobalMantle, Experimental petrology
DS1990-0601
1990
Green, D.H.Green, D.H., Taylor, W.R., Foley, S.The earth's upper mantle as a source for volatilesUniversity of Western Australia Publishing, Proceedings on Conference on stable isotopes and, No. 23, pp. 17-34GlobalMantle, Geochemistry
DS1990-1128
1990
Green, D.H.Odling, N.W.A., Mernagh, T., Green, D.H.high pressure, high temperature fluid inclusion synthesis: analysis andimplicationsTerra, Abstracts of Experimental mineralogy, petrology and, Vol. 2, December abstracts p. 89GlobalMantle, Xenoliths
DS1991-0065
1991
Green, D.H.Ballhaus, C., Berry, R.F., Green, D.H.high pressure experimental calibration of the olivine ortho pyroxene spinel oxygen geobarometer-implications for the oxidation state of the upper mantleContributions to Mineralogy and Petrology, Vol. 107, No. 1, pp. 27-40GlobalMantle, Geobarometry
DS1991-0790
1991
Green, D.H.Jenner, G., Green, D.H.Petrogenesis of type 3 low Calcium boninitesEos Transactions, Vol. 72, No. 44, October 29, abstract p. 519GlobalBoninites, Petrology
DS1991-1078
1991
Green, D.H.Mattey, D.P., Taylor, W.R., Green, D.H.Carbon isotope fractionation between CO2 vapour and silicate melts at 5-30KBARSTerra, Abstracts of Experimental mineralogy, petrology and, Vol. 2, December abstracts p. 88GlobalExperimental petrology, Carbonatite
DS1991-1254
1991
Green, D.H.Olding, N.W.A., Green, D.H., Harte, B.The composition of partial melts in a volatile bearing reduced mantleProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 313-315GlobalExperimental petrology, Xenoliths, partial melt composition
DS1991-1682
1991
Green, D.H.Sweeney, R.J., Falloon, T.J., Green, D.H., Tatsumi, Y.The mantle origin of Karoo picritesEarth and Planetary Science Letters, Vol. 107, No. 2, November pp. 256-271South AfricaPicrites, Mantle
DS1991-1702
1991
Green, D.H.Taylor, W.R., Green, D.H.Mineral chem. of silicate and oxide phases from fertile peridotite equilibrated with a C-O-H fluid phase- a low fO2 dat a set- evaluation of mineralbarometers, therM.Proceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 417-419GlobalExperimental petrology, Geobarometry
DS1991-1825
1991
Green, D.H.Wallace, M.E., Green, D.H.The effect of bulk rock composition on the stability of amphibole in The upper mantle- implications for solidus positions and mantle MetasomatismMineral. Petrol, Vol. 44, No. 1-2, pp. 1-19GlobalMantle, Geochemistry
DS1991-1907
1991
Green, D.H.Yaxley, G.M., Crawford, A.J., Green, D.H.Evidence for carbonatite metasomatism in spinel peridotite xenoliths from western Victoria, AustraliaEarth and Planetary Science Letters, Vol. 107, No. 2, November pp. 305-317AustraliaCarbonatite, Xenoliths
DS1992-0603
1992
Green, D.H.Green, D.H.The earth's lithosphere and asthenosphere; concepts and constraints derived from petrology and high pressure experiments.The Australian Lithosphere, Geol. Society of Australia, Vol. 17, pp. 1-22.AustraliaCraton, Archean
DS1992-1506
1992
Green, D.H.Sweeney, R.J., Green, D.H., Sie, S.H.Trace and minor element partioning between garnet and amphibole and carbonatitic meltEarth and Planetary Science Letters, Vol. 113, No. 1-2, September pp. 1-14GlobalCarbonatite, Mineral chemistry
DS1992-1719
1992
Green, D.H.Yaxley, G., Green, D.H., Crawford, A.J.Carbonatite metasomatism: observations and implications11th. Australian Geol. Convention Held Ballarat University College, Jan., Listing of papers to be given attempting to get volAustraliaCarbonatite, Metasomatism
DS1993-0572
1993
Green, D.H.Green, D.H.The melting behaviour of the Earth's upper mantle and implications for mantle dynamics.Russian Geology and Geophysics, Vol. 34, No. 12, pp. 148-161.MantleGeodynamics, Melting
DS1994-0657
1994
Green, D.H.Green, D.H.Experimental definition of mantle melting and implications for mantledynamics.Mineralogical Magazine, Vol. 58A, pp. 350-351. AbstractMantleGeodynamics, Xenoliths
DS1994-1731
1994
Green, D.H.Sweeney, R.J., Falloon, T.J., Green, D.H.Experimental constraints on the possible mantle originCarbonatite volcanism, Ed. Bell, K., Keller, J., pp. 191-208.TanzaniaDeposit -Oldoinyo Lengai
DS1994-1962
1994
Green, D.H.Yaxley, G.M., Green, D.H.Experimental demonstration of refractory carbonate eclogite and siliceous melt in the subduction regime.Earth Planetary Science Letters, Vol. 128, No. 3-4, Dec. pp. 313-326.GlobalEclogite, Subduction
DS1994-1963
1994
Green, D.H.Yaxley, G.M., Green, D.H., Klapova, H.The refractory nature of carbonate during partial melting of eclogite:evidence from experiments.Mineralogical Magazine, Vol. 58A, pp. 9996-997. AbstractMantleEclogites, Carbonates
DS1996-0562
1996
Green, D.H.Green, D.H.Experimental constraints on kimberlite genesisAustralia Nat. University of Diamond Workshop July 29, 30., 10p.MantleMelting, phase relationships, Redox, lherzolite, harzburgite
DS1997-0332
1997
Green, D.H.Falloon, T.J., Green, D.H., O'Neill, H., Hibberson, W.Experimental tests of low degree peridotite partial melt compositions:implications for the nature ....Earth and Plan. Sci. Letters, Vol. 152, No. 1-4, pp. 149-162.GlobalPetrology - experimental, Andesitic melts, lherzolites
DS1997-1281
1997
Green, D.H.Yaxley, G.M., Green, D.H., Kamenetsky, V.Carbonatite metasomatism in the southeastern Australian lithosphere. #1Geological Association of Canada (GAC) Abstracts, AustraliaCarbonatite
DS1997-1282
1997
Green, D.H.Yaxley, G.M., Kamenets, V., Green, D.H., Falloon, T.J.Classes in mantle xenoliths from Western Victoria Australia, and their relevance to mantle processes.Earth Planetary Science Letters, Vol. 148, No. 3-4, May pp. 433-446.AustraliaXenoliths, Mantle
DS1998-1615
1998
Green, D.H.Yaxley, G.M., Green, D.H.Phase relations of carbonated eclogite under upper mantle PT condition simplications for carbonatite....7th International Kimberlite Conference Abstract, pp. 983-85.MantleExperimental petrology, Eclogites, carbonatite
DS1998-1616
1998
Green, D.H.Yaxley, G.M., Green, D.H., Kamenetsky, V.Carbonatite metasomatism in the southeastern Australian lithosphere. #2Journal of Petrology, Vol. 39, No. 11-12, Nov-Dec. pp. 1917-30.AustraliaCarbonatite, Metasomatism
DS1999-0202
1999
Green, D.H.Falloon, T.J., Green, D.H., Faul, U.H.Peridotitic melting at 1 and 1.5 GPa: an experimental evaluation of techniques using diamond aggregates...Journal of Petrology, Vol. 40, No. 9, Sept. pp. 1343-76.GlobalPetrology - experimental, Melting - near solidus melts, mineral mixes
DS1999-0508
1999
Green, D.H.Niida, K., Green, D.H.Stability and chemical composition of pargasitic amphibole Mid Ocean Ridge Basalt (MORB) pyrolite under upper mantle conditions.Contributions to Mineralogy and Petrology, Vol. 135, No. 1, pp. 18-40.MantleGeochemistry, Pyrolite - amphibole
DS2001-0407
2001
Green, D.H.Green, D.H., Falloon, T.J., Eggins, S.M., Yaxley, G.M.Primary magmas and mantle temperaturesEuropean Journal of Mineralogy, Vol. 13, No. 3, pp. 437-51.MantleMagmatism, Melting, subduction, slabs, hotspots
DS2001-0474
2001
Green, D.H.Hermann, J., Green, D.H.Experimental constraints on high pressure melting in subducted crustEarth and Planetary Science Letters, Vol. 188, No. 1, May 30, pp.149-68.Mantleultra high pressure (UHP), Subduction
DS2001-0844
2001
Green, D.H.Nutman, A.P., Green, D.H., Cook, C.A., Styles, M.T.Shrimp uranium-lead (U-Pb) zircon dating of the exhumation of the Lizard peridotite and its emplacement over crustal rockJour. Geol. Soc. Lond., Vol. 158, No. 5, pp. 809-20.United KingdomGeochronology, Peridotite - Lizard
DS200412-0713
2004
Green, D.H.Green, D.H., Schmidt, M.W., Hibberson, W.O.Island arc ankaramites: primitive melts from fluxed refractory lherzolitic mantle.Journal of Petrology, Vol. 45, 2, pp. 391-403.MantlePetrology
DS200412-1759
2004
Green, D.H.Schmidt, T., Green, D.H., Hibberson, W.O.Ultra calcic magmas generated from Ca depleted mantle: an experimental study on the origin of ankaramites.Journal of Petrology, Vol. 45, 3, pp. 531-554.MantleMagmatism, melt inclusions - not specific to diamonds
DS200512-0241
2005
Green, D.H.Doglioni, C., Green, D.H., Mongelli, F.On the shallow origin of hotspots and the westward drift of the lithosphere.Plates, Plumes, and Paradigms, pp. 735-750. ( total book 861p. $ 144.00)MantleGeophysics
DS200512-0363
2005
Green, D.H.Green, D.H., Falloon, T.J.Primary magmas at mid-ocean ridges, 'hotspots' and other intraplate settings: constraints on mantle potential temperatures.Plates, Plumes, and Paradigms, pp. 217-248. ( total book 861p. $ 144.00)MantleGeothermometry
DS200612-0493
2006
Green, D.H.Green, D.H.Why does the Earth have lithosphere of around 90 km thickness in oceanic and many continental intraplate settings?Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 213, abstract only.MantleGeophysics - seismics, tectonics
DS200712-0303
2007
Green, D.H.Fallon, T.J., Danyushevsky, L.V., Ariskin, A., Green, D.H., Ford, C.E.The application of olivine geothermometry to infer crystallization temperatures of parental liquids; implications for the temperature of MORB magmas.Chemical Geology, Vol. 241, 3-4, pp. 207-233.MantleGeothermometry
DS200712-0910
2007
Green, D.H.Rosenthal, A., Yaxley, G.M., Green, D.H., Hermann, J., Spandler, C.S.Phase and melting relations of a residual garnet clinopyroxenite.Plates, Plumes, and Paradigms, 1p. abstract p. A851.MantleMelting
DS200712-1202
2007
Green, D.H.Yaxley, G.M., Spandler, C.S., Green, D.H., Rosenthal, A., Brey, G.P.The influence of minor elements on melting of eclogite in the mantle.Plates, Plumes, and Paradigms, 1p. abstract p. A1143.MantleMelting
DS200812-0429
2008
Green, D.H.Green, D.H., Hibberson, W.O., O'Neill, H.St.C.Clarification of the influence of water on mantle wedge melting.Goldschmidt Conference 2008, Abstract p.A325.MantleMelting
DS200812-0972
2008
Green, D.H.Rosenthal, A., Yaxley, G.M., Green, D.H., Hermann, J., Spandler, C.S.Melting of residual eclogites with variable proportions of quartz coesite.Goldschmidt Conference 2008, Abstract p.A806.TechnologyMagma genesis
DS200912-0838
2009
Green, D.H.Yaxley, G.M., Spandler, C.S., Sobolev, A.V., Rosenthal, A., Green, D.H.Melting and melt peridotite interactions in heterogeneous upper mantle sources of primitive volcanics.Goldschmidt Conference 2009, p. A1482 Abstract.MantleMelting
DS201012-0638
2010
Green, D.H.Rosenthal, A., Yaxley, G.M., Green, D.H., Hermann, J., Spandler, C.S., Kovacs, I., Mernagh, T.P.Phase and melting relations of a residual eclogite within an upwelling heterogeneous upper mantle.International Mineralogical Association meeting August Budapest, abstract p. 156.MantlePetrogenesis
DS201112-0199
2010
Green, D.H.Conceicao, R.V., Green, D.H., Lenz, C., Gervasconi, F., Drago, S.Derivation of potassic magmas by decompression melting of phlogopite+pargasite lherzolite.5th Brasilian Symposium on Diamond Geology, Nov. 6-12, abstract p. 74.MantleMetasomatism
DS201112-1040
2011
Green, D.H.Tian, W., Chen, B., Ireland, T.R., Green, D.H., Suzuki, K., Chu, Z.Petrology and geochemistry of dunites, chromitites and mineral inclusions from the Gaositai Alaskan type complex, North Chin a craton: mantle source charactersLithos, Vol. 127, 1-2, pp. 165-175.ChinaCarbonatite
DS201212-0379
2012
Green, D.H.Kovacs, I., Green, D.H., Rosenthal, A., Hermann, J., St.O'Neill, H., Hibberson, W.O., Udvardi, B.An experimental study of water in nominally anhydrous minerals in the upper mantle near the water saturated solidus.Journal of Petrology, Vol. 53, 10, pp. 2067-2093.MantleWater content
DS201212-0598
2012
Green, D.H.Rosenthal, A., Green, D.H., Kovacs, I., Hibberson, W.O., Yaxley, G.M., Brink, F.Experimental study of the role of water in the uppermost mantle.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractMantleWater
DS201212-0599
2012
Green, D.H.Rosenthall, A., Yaxley, G.M., Green, D.H., Kovacs, I., Herman, J., Spandler, C.S., Mernagh, T.P.Phase and melting relations of a residue eclogite/pyroxenite within an upwelling heterogeneous upper mantle.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractMantleMelting
DS201412-0312
2014
Green, D.H.Green, D.H., Hibberson, W.O., Rosenthal, A., Kovasc, I., Yaxley, G.M., Falloon, T.J., Brink, F.Experimental study of the influence of water on melting and phase assemblages in the upper mantle.Journal of Petrology, Vol. 55, 10, pp. 2067-2096.MantleMelting
DS201503-0145
2015
Green, D.H.Green, D.H.Experimental petrology of peridotites, including effects of water and carbon on melting in the Earth's upper mantle.Physics and Chemistry of Minerals, Vol. 42, 2, pp. 95-122.MantlePeridotite

Abstract: For over 50 years, the use of high-pressure piston/cylinder apparatus combined with an increasing diversity of microbeam analytical techniques has enabled the study of mantle peridotite compositions and of magmas derived by melting in the upper mantle. The experimental studies have been guided by the petrology and geochemistry of peridotites from diverse settings and by the remarkable range of mantle-derived magma types. Recent experimental study using FTIR spectroscopy to monitor water content of minerals has shown that fertile lherzolite (MORB-source upper mantle) at ~1,000 °C can store ~200 ppm H2O in defect sites in nominally anhydrous minerals (olivine, pyroxenes, garnet and spinel). Water in excess of 200 ppm stabilizes amphibole (pargasite) at P < 3 GPa up to the lherzolite solidus. However, at P > 3 GPa, water in excess of 200 ppm appears as an aqueous vapour phase and this depresses the temperature of the upper mantle solidus. Provided the uppermost mantle (lithosphere) has H2O < 4,000 ppm, the mantle solidus has a distinctive P, T shape. The temperature of the vapour-undersaturated or dehydration solidus is approximately constant at 1,100 °C at pressures up to ~3 GPa and then decreases sharply to ~1,010 °C. The strongly negative dT/dP of the vapour-undersaturated solidus of fertile lherzolite from 2.8 to 3 GPa provides the basis for understanding the lithosphere/asthenosphere boundary. Through upward migration of near-solidus hydrous silicate melt, the asthenosphere becomes geochemically zoned with the ‘enriched’ intraplate basalt source (>500 ppm H2O) overlying the ‘depleted’ MORB source (~200 ppm H2O). From the study of primitive MOR picrites, the modern mantle potential temperature for MORB petrogenesis is ~1,430 °C. The intersection of the 1,430 °C adiabat with the vapour-saturated lherzolite solidus at ~230 km suggests that upwelling beneath mid-ocean ridges begins around this depth. In intraplate volcanism, diapiric upwelling begins from shallower depths and lower temperatures within the asthenosphere and the upwelling lherzolite is enriched in water, carbonate and incompatible elements. Magmas including olivine melilitites, olivine nephelinites, basanites, alkali picrites and tholeiitic picrites are consequences of increasing melt fraction and decreasing pressure at melt segregation. Major element, trace element and isotopic characteristics of island chain or ‘hot-spot’ magmas show that they sample geochemically distinct components in the upper mantle, differing from MORB sources. There is no evidence for higher-temperature ‘hot-spot’ magmas, relative to primitive MORB, but there is evidence for higher water, CO2 and incompatible element contents. The distinctive geochemical signatures of ‘hot-spot’ magmas and their ‘fixed’ position and long-lived activity relative to plate movement are attributed to melt components derived from melting at interfaces between old, oxidised subducted slabs (suspended beneath or within the deeper asthenosphere) and ambient, reduced mantle. In convergent margin volcanism, the inverted temperature gradients inferred for the mantle wedge above the subducting lithosphere introduce further complexity which can be explored by overlaying the phase relations of appropriate mantle and crustal lithologies. Water and carbonate derived from the subducted slab play significant roles, magmas are relatively oxidised, and distinctive primary magmas such as boninites, adakites and island arc ankaramites provide evidence for fluxing of melting in refractory harzburgite to lherzolite by slab-derived hydrous adakitic melt and by wedge-derived carbonatite.
DS201611-2111
2015
Green, D.H.Green, D.H.Experimental petrology of peridotites, including effects of water and carbon on melting in the Earth's upper mantle.Physics and Chemistry of Minerals, Vol. 42, pp. 95-102.MantlePeridotite

Abstract: For over 50 years, the use of high-pressure piston/cylinder apparatus combined with an increasing diversity of microbeam analytical techniques has enabled the study of mantle peridotite compositions and of magmas derived by melting in the upper mantle. The experimental studies have been guided by the petrology and geochemistry of peridotites from diverse settings and by the remarkable range of mantle-derived magma types. Recent experimental study using FTIR spectroscopy to monitor water content of minerals has shown that fertile lherzolite (MORB-source upper mantle) at ~1,000 °C can store ~200 ppm H2O in defect sites in nominally anhydrous minerals (olivine, pyroxenes, garnet and spinel). Water in excess of 200 ppm stabilizes amphibole (pargasite) at P < 3 GPa up to the lherzolite solidus. However, at P > 3 GPa, water in excess of 200 ppm appears as an aqueous vapour phase and this depresses the temperature of the upper mantle solidus. Provided the uppermost mantle (lithosphere) has H2O < 4,000 ppm, the mantle solidus has a distinctive P, T shape. The temperature of the vapour-undersaturated or dehydration solidus is approximately constant at 1,100 °C at pressures up to ~3 GPa and then decreases sharply to ~1,010 °C. The strongly negative dT/dP of the vapour-undersaturated solidus of fertile lherzolite from 2.8 to 3 GPa provides the basis for understanding the lithosphere/asthenosphere boundary. Through upward migration of near-solidus hydrous silicate melt, the asthenosphere becomes geochemically zoned with the ‘enriched’ intraplate basalt source (>500 ppm H2O) overlying the ‘depleted’ MORB source (~200 ppm H2O). From the study of primitive MOR picrites, the modern mantle potential temperature for MORB petrogenesis is ~1,430 °C. The intersection of the 1,430 °C adiabat with the vapour-saturated lherzolite solidus at ~230 km suggests that upwelling beneath mid-ocean ridges begins around this depth. In intraplate volcanism, diapiric upwelling begins from shallower depths and lower temperatures within the asthenosphere and the upwelling lherzolite is enriched in water, carbonate and incompatible elements. Magmas including olivine melilitites, olivine nephelinites, basanites, alkali picrites and tholeiitic picrites are consequences of increasing melt fraction and decreasing pressure at melt segregation. Major element, trace element and isotopic characteristics of island chain or ‘hot-spot’ magmas show that they sample geochemically distinct components in the upper mantle, differing from MORB sources. There is no evidence for higher-temperature ‘hot-spot’ magmas, relative to primitive MORB, but there is evidence for higher water, CO2 and incompatible element contents. The distinctive geochemical signatures of ‘hot-spot’ magmas and their ‘fixed’ position and long-lived activity relative to plate movement are attributed to melt components derived from melting at interfaces between old, oxidised subducted slabs (suspended beneath or within the deeper asthenosphere) and ambient, reduced mantle. In convergent margin volcanism, the inverted temperature gradients inferred for the mantle wedge above the subducting lithosphere introduce further complexity which can be explored by overlaying the phase relations of appropriate mantle and crustal lithologies. Water and carbonate derived from the subducted slab play significant roles, magmas are relatively oxidised, and distinctive primary magmas such as boninites, adakites and island arc ankaramites provide evidence for fluxing of melting in refractory harzburgite to lherzolite by slab-derived hydrous adakitic melt and by wedge-derived carbonatite.
DS201611-2112
2015
Green, D.H.Green, D.H., Falloon, T.J.Mantle-derived magmas: intraplate, hot spots and mid-ocean ridges.Science Bulletin, Vol. 60, 22, pp. 1873-1900.MantleHotspots

Abstract: Primary or parental magmas act as probes to infer eruption and source temperatures for both mid-ocean ridge (MOR) and ‘hot-spot’ magmas (tholeiitic picrites). The experimental petrogenetic constraints (‘inverse’ experiments) argue for no significant temperature differences between them. However, there are differences in major, minor and trace elements which characterise geochemical, not thermal, anomalies beneath ‘hot-spots’. We suggest that diapiric upwelling from interfaces (redox contrasts) between old subducted slab and normal MOR basalt source mantle is the major reason for the observed characteristics of island chain or ‘hot-spot’ volcanism. Intraplate basalts also include widely distributed volcanic centres containing lherzolite xenoliths, i.e. mantle-derived magmas. Inverse experiments on olivine basalt, alkali olivine basalt, olivine basanite, olivine nephelinite, olivine melilitite and olivine leucitite (lamproite) determined liquidus phases as a function of pressure, initially under anhydrous and CO2-absent conditions. Under C- and H-absent conditions, only tholeiites to alkali olivine basalts had Ol + Opx ± Cpx as high-pressure liquidus phases. Addition of H2O accessed olivine basanites at 2.5-3 GPa, ~1,200 °C, but both CO2 and H2O were necessary to obtain saturation with Ol, Opx, Cpx and Ga at 2.5-3.5 GPa for olivine nephelinite and olivine melilitite. The forward and inverse experimental studies are combined to formulate a petrogenetic grid for intraplate, ‘hot-spot’ and MOR magmatism within the plate tectonics paradigm. The asthenosphere is geochemically zoned by slow upward migration of incipient melt. The solidus and phase stabilities of lherzolite with very small water contents (<3,000 ppm) determine the thin plate behaviour of the oceanic lithosphere and thus the Earth’s convection in the form of plate tectonics. There is no evidence from the parental magmas of MOR and ‘hot-spots’ to support the ‘deep mantle thermal plume’ hypothesis. The preferred alternative is the presence of old subducted slabs, relatively buoyant and oxidised with respect to MORB source mantle and suspended or upwelling in or below the lower asthenosphere (and thus detached from overlying plate movement).
DS2001-0312
2001
Green, D.M.Fallon, T.J., Danyushevsky, L.V., Green, D.M.Peridotite melting at 1 GPA: reversal experiments on partial melt compositions produced by peridotite basaltJournal Petrology, Vol. 42, No. 12, pp. 2363-85.MantleExperiments - sandwich, Melting
DS201906-1337
2019
Green, E.C.R.Powell, R., Evans, K.A., Green, E.C.R., White, R.W.The truth and beauty of chemical potentials.Journal of Metamorphic Geology, doi.org.10.1111/ jmg.12484Globalgeochemistry

Abstract: This essay in honour of Mike Brown addresses aspects of chemical equilibrium and equilibration in rocks, with a focus on the role that chemical potentials play. Chemical equilibrium is achieved by diffusive flattening of chemical potential gradients. The idea of equilibration volume is developed, and the way equilibration volumes may evolve along a pressure-temperature path is discussed. The effect of the environment of an equilibration volume is key to understanding the evolution of the equilibration volume with changing conditions. The likely behaviour of equilibration volumes is used to suggest why preservation of equilibrium mineral assemblages and mineral compositions from metamorphism tends to occur. This line of logic then provides the conceptual support to conventional equilibrium thermodynamic approaches to studying rocks, using, for example, thermobarometry and pseudosections.
DS1940-0151
1947
Green, G.A.L.Green, G.A.L.An Editor Looks BackCape Town: Juta., South Africa, Cape ProvinceKimberley, History, Travelogue
DS1990-1329
1990
Green, G.N.Selner, G.I., Green, G.N.DLGGSMUnited States Geological Survey (USGS) Open File, No. 90-0459 A, B, 5p. 1 disc. $ 1.25 and $ 6.00GlobalProgram -DLGGSM.
DS1994-0658
1994
Green, G.N.Green, G.N., Drouillard, P.H.The digital geologic map of Wyoming in Arc/INFO formatUnited States Geological Survey (USGS) Open file, No. 94-0425, 10p. $ 1.75WyomingMap, GIS -digitized
DS2001-0263
2001
Green, H.Dobrzhinetskaya, L.F., Green, H., Mitchell, T., DickersonMetamorphic diamonds: mechanisms of growth and inclusion of oxideGeology, Vol. 29, No. 3, Mar. pp. 263-6.GlobalDiamond inclusions, morphology, Deposit - Kokchetav Massif
DS200912-0179
2009
Green, H.Dobrzhinetskaya, L.F., Wirth, R., Green, H.Lamellae of phylosilicates in K rich diopside from UHP marble of the Kokchetav massif, Kazakhstan: FIB-TEM and synchrotron IR studies.Goldschmidt Conference 2009, p. A296 Abstract.RussiaUHPM - diamond inclusions
DS201412-0197
2014
Green, H.Dobrzhinetskaya, L., Wirth, R., Green, H.Diamonds in Earth's oldest zircons from Jack Hills conglomerate, Australia, are contamination.Earth and Planetary Science Letters, Vol. 387, pp. 212-218.AustraliaDiamond inclusions
DS1970-0917
1974
Green, H.W.Green, H.W., Gueguen, Y.Origin of the Kimberlite Pipes by Upwelling in the Upper Mantle.Nature., Vol. 249, No. 5458, PP. 617-620.South Africa, West AfricaKimberlite Genesis
DS1980-0148
1980
Green, H.W.Green, H.W., Gueguen, Y.Deformation of Peridotite in the Mantle and Extraction by Kimberlite.Eos, Vol. 61, No. 46, P. 1156. (abstract.).United States, Colorado PlateauBlank
DS1986-0302
1986
Green, H.W.Green, H.W., Borch, R., Hobbs, B.E.The pressure dependence of creep in olivine: consequences formantleflowProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 244-246GlobalBlank
DS1986-0806
1986
Green, H.W.Tingle, T.N., Green, H.W., Finnerty, A.A.The solubility and diffusivity of carbon in olivine:implications for carbon in the earth's upper mantleProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 349-351New MexicoSan Carlos
DS1988-0698
1988
Green, H.W.Tingle, T.N., Green, H.W., Finnerty, A.A.Experiments and observations bearing on the solubility and diffusivity of carbon in olivine #1Journal of Geophysical Research, Vol. 93, No. B12, December 10, pp. 15, 289- 15, 304GlobalOlivine, Experimental petrology
DS1989-0538
1989
Green, H.W.Green, H.W., Burnley, P.C.A new self organizing mechanism for deep focus earthquakesNature, Vol. 341, October 26, pp. 733-737. Database #18212GlobalMantle, Model -earthquakes
DS1989-1501
1989
Green, H.W.Tingle, T.N., Green, H.W., Finnerty, A.A.Experiments and observations bearing on the solubility and diffusivity of carbon in olivine #2Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 2, pp. 922-934GlobalRequested not to be cited, Included for citation onl
DS1992-1739
1992
Green, H.W.Zhen-Ming Jin, Green, H.W., Borch, R.S., Shu-Yan Jin, Tingle, T.N.Rare garnet and spinel garnet peridotite xenoliths -token of a modern back-arc geotherm beneath eastern ChinaInternational Symposium Cenozoic Volcanic Rocks Deep seated xenoliths China and its, Abstracts pp. 67-68ChinaXenoliths, Peridotite
DS1994-0847
1994
Green, H.W.Jin, Z-M., Green, H.W., Shou, Y.Melt topology in partially molten mantle peridotite during ductiledeformation.Nature, Vol. 372, No. 6502, Nov. 10, pp. 164-166.MantleMelting
DS1999-0170
1999
Green, H.W.Dobrzhinetskaya, L., Bpzilov, K.N., Green, H.W.The solubility of TiO2 in olivine: implications for the mantle wedgeenvironment.Chemical Geology, Vol. 160, No. 4, Sept. 2, pp. 357-70.MantleMineral chemistry - olivine
DS2000-0626
2000
Green, H.W.Massone, H.J., Dobrzhinetskaya, L., Green, H.W.Quartz Potassium feldspar intergrowths enclosed in eclogitic garnet and omphacite. are pseudomorphs after coesite?Igc 30th. Brasil, Aug. abstract only 4p.Globalmetamorphism, Dabie Shan
DS2001-0408
2001
Green, H.W.Green, H.W.Plate tectonics: a graveyard for bouyant slabs?Science, No. 5526, June 29, pp. 2445-6.MantleSubduction
DS2001-0537
2001
Green, H.W.Jin, Z.M., Zhang, J., Green, H.W., Jin, S.Eclogite rheology: implications for subducted lithosphereGeology, Vol. 29, No. 8, Aug. pp. 667-70.ChinaGarnet, subduction, ultra high pressure (UHP), Dabie Shan
DS2003-0339
2003
Green, H.W.Dobrzhinetskaya, L.F., Green, H.W., Bozhilov, K.N., Mitchell, T.E., Dickerson, R.M.Crystallization environment of Kazakhstan microdiamond: evidence from nanometricJournal of Metamorphic Geology, Vol. 21, 5, pp. 425-38.Russia, KazakhstanMineral inclusions
DS2003-0340
2003
Green, H.W.Dobrzhinetskaya, L.F., Green, H.W., Weschler, M., Darus, M., Wang, Y.C.Focused ion beam technique and transmission electron microscope studies ofEarth and Planetary Science Letters, Vol. 210, 3-4, pp. 399-410.GermanyTechnology
DS2003-0341
2003
Green, H.W.Dobrzhinetskaya, L.F., Green, H.W., Weschler, M., Darus, M., Young-ChungFocused ion beam technique and transmission electron microscope studies ofEarth and Planetary Science Letters, Vol. 210, 3-4, May 30, pp.399-410.GermanyDiamond inclusions
DS2003-0496
2003
Green, H.W.Green, H.W.Psychology of a changing paradigm: ultra high pressure metamorphismGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.95.MantleUHP
DS200412-0463
2003
Green, H.W.Dobrzhinetskaya, L.F., Green, H.W., Bozhilov, K.N., Mitchell, T.E., Dickerson, R.M.Crystallization environment of Kazakhstan microdiamond: evidence from nanometric inclusions and mineral associations.Journal of Metamorphic Geology, Vol. 21, 5, pp. 425-38.Russia, KazakhstanMicrodiamonds, mineral inclusions
DS200412-0464
2003
Green, H.W.Dobrzhinetskaya, L.F., Green, H.W., Weschler, M., Darus, M., Young-Chung, Wang, Massone, H-J., Stockhert, B.Focused ion beam technique and transmission electron microscope studies of microdiamonds from the Saxonian Erzgerbirge, Germany.Earth and Planetary Science Letters, Vol. 210, 3-4, May 30, pp.399-410.Europe, GermanyDiamond inclusions
DS200412-0714
2003
Green, H.W.Green, H.W.Psychology of a changing paradigm: ultra high pressure metamorphism.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p.95.MantleUHP
DS200412-2169
2003
Green, H.W.Yang, J., Xu, Z., Dobrzhinetskaya, L.F., Green, H.W., Pei, X., Shi, R., Wu, C., Wooden, J.L., Zhang, J., WanDiscovery of metamorphic diamonds in central China: an indication of a > 4000 km long zone of deep subduction resulting from mulTerra Nova, Vol. 15, pp. 370-379.ChinaSubduction, Central Orogenic Belt, UHP
DS200512-0238
2004
Green, H.W.Dobrzhinetskaya, L.F., Green, H.W., Renfro, A.P., Bozhilov, K.N., Spengler, D., Van Roemund, H.L.M.Precipitation of pyroxenes and Mg2SiO4 from majorite garnet: simulation of peridotite exhumation from great depth.Terra Nova, Vol. 16, 6, pp. 325-330.MantlePetrology - peridotite
DS200512-0240
2005
Green, H.W.Dobrzhinetskaya, L.F., Wirth, R., Green, H.W.Direct observation and analysis of a trapped COH fluid growth medium in metamorphic diamond.Terra Nova, Vol. 17, 5, Oct. pp. 472-477.KazakhstanDiamond morphology, metamorphic, UHP Kokchetav Massif
DS200512-0364
2005
Green, H.W.Green, H.W.Psychology of a changing paradigm: 40 + years of high pressure metamorphism.International Geology Review, Vol. 47, 5, May, pp. 439-456.MantleUHP
DS200612-0339
2005
Green, H.W.Dobrzhinetskaya, L.F., Wirth, R., Green, H.W.Direct observation and analysis of a trapped COH fluid growth medium in metamorphic diamond.Terra Nova, Vol. 17, 5, pp. 472-477.MantleUHP
DS200712-0254
2007
Green, H.W.Dobrzhinetskaya, L., Liu, Z., Green, H.W.Synchrotron infrared spectroscopy: confirmation of metamorphic diamond crystallization from C-O-H fluid. ( Erzgebirge region).Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p.149.Europe, GermanyDiamond genesis
DS200712-0255
2007
Green, H.W.Dobrzhinetskaya, L., Liu, Z., Green, H.W.Synchrotron infrared spectroscopy: confirmation of metamorphic diamond crystallization from C-O-H fluid. ( Erzgebirge region).Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p.149.Europe, GermanyDiamond genesis
DS200712-0256
2007
Green, H.W.Dobrzhinetskaya, L., Takahata, N., Sano, Y., Green, H.W.Fluid organic matter interaction at high pressure and temperature: evidence from metamorphic diamonds.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 279.Russia, Kazakhstan, Europe, GermanyKokchetav and Erzgebirge
DS200712-0257
2007
Green, H.W.Dobrzhinetskaya, L., Takahata, N., Sano, Y., Green, H.W.Fluid organic matter interaction at high pressure and temperature: evidence from metamorphic diamonds.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 279.Russia, Kazakhstan, Europe, GermanyKokchetav and Erzgebirge
DS200712-0258
2007
Green, H.W.Dobrzhinetskaya, L.F., Green, H.W.Diamond synthesis from graphite in the presence of water and SiO2: implications for diamond formation in quartzites from Kazakhstan.International Geology Review, Vol. 49, 5, pp. 389-400.Russia, KazakhstanDiamond genesis
DS200712-0259
2007
Green, H.W.Dobrzhinetskaya, L.F., Green, H.W.Experimental studies of mineralogical assemblages of metasedimentary rocks at Earth's mantle transition zone conditions.Journal of Metamorphic Geology, Vol. 25, 2, pp. 83-96.MantleMineralogy
DS200712-0260
2007
Green, H.W.Dobrzhinetskaya, L.F., Wirth, R., Green, H.W.A look inside of diamond forming media in deep subduction zones.Proceedings of National Academy of Sciences USA, Vol. 104, 22, pp. 9128-9132. IngentaMantleSubduction
DS200712-0641
2007
Green, H.W.Liu, X., Jin,Z., Green, H.W.Clinoenstatite exsolution in diopsidic augite of Dabie Shan - garnet peridotite from depth of 300 km.Americam Mineralogist, Vol. 92, 4, pp. 546-552.ChinaUHP
DS200912-0177
2008
Green, H.W.Dobrzhinetskaya, L., Wirth, R., Yang, J., Green, H.W.Nontraditional 'deliverers' of UHP rocks from Earth's deep interior to surface.American Geological Union, Fall meeting Dec. 15-19, Eos Trans. Vol. 89, no. 53, meeting supplement, 1p. abstractMantleUHP
DS200912-0180
2009
Green, H.W.Dobrzhinetskaya, L.F., Wirth, R., Rhede, D., Liu, Z., Green, H.W.Phlogopite and quartz lamellae in diamond bearing diopside from marbles of the Kokchetav massif, Kazakhstan: exsolution or replacement reaction?Journal of Metamorphic Geology, Vol. 27, 9, pp. 607-620.Russia, KazakhstanDeposit - Kokchetav
DS200912-0347
2009
Green, H.W.Jung, H., Mo, W., Green, H.W.Upper mantle seismic anisotropy resulting from pressure induced slip transition in olivine.Nature Geoscience, Vol. 2, 1, pp. 73-77.MantleAnisotropy
DS201012-0643
2010
Green, H.W.Ruskov, T., Spirov, I., Georgieva, M., Yamamoto, S., Green, H.W., McCammon, C.A., Dobrzhinetskaya, L.F.Mossbauer spectroscopy studies of the valence state of iron in chromite from the Luobusa Massif of Tibet: implications for a highly reduced mantle.Journal of Metamorphic Geology, Vol. 28, 5, pp. 551-560.Asia, TibetMetasomatism
DS201012-0853
2010
Green, H.W.Wirth, R., Dobrzhinetskaya, L., Harte, B., Green, H.W.Tubular Mg ferrite in magnesiowustite inclusions in diamond from superdeep origin: control of Fe valence by dislocation core structure.International Mineralogical Association meeting August Budapest, abstract p. 210.South America, BrazilPetrology
DS201112-0279
2011
Green, H.W.Dobrzhinetskaya, L., Wirth, R., Green, H.W., Sumino, H.Fluids nature at peak of ultrahigh pressure metamorphism in deep subduction zones - evidence from diamonds.Goldschmidt Conference 2011, abstract p.769.Russia, Kazakhstan, Europe, GermanyUHP - Kokchetav
DS201112-1161
2011
Green, H.W.Zhang, J.F., Xu, H.J., Liu, Q., Green, H.W., Dobrzhinetskaya, L.F.Pyroxene exsolution topotaxy in majoritic garnet from 250 to 300 km depth.Journal of Metamorphic Geology, Vol. 29, 7, pp. 741-751.TechnologyGarnet mineralogy
DS201112-1162
2011
Green, H.W.Zhang, J.F., Xu, H.J., Liu, Q., Green, H.W., Dobrzhinetskaya, L.F.Pyroxene evolution topotaxy in majorite garnet from 250 to 300 km depth.Journal of Metamorphic Geology, In press available,MantleGarnet
DS201212-0163
2013
Green, H.W.Dobrzhinetskaya, L.F., Wirth, R., Green, H.W., Schreiber, A., O'Bannon, E.First find of polycrystalline diamond in ultrahigh-pressure metamorphic terrane of Erzgebirge, Germany.Journal of Metamorphic Geology, Vol. 31, 1, pp. 5-18.Europe, GermanyUHP
DS201212-0164
2012
Green, H.W.Dobrzhinskaya, L.F., Wirth, R., Green, H.W., Schreiber, A., O'bannon, E.First find of polycrystalline diamond in ultrahigh pressure metamorphic terrane of Erzgebirge Germany.Journal of Metamorphic Geology, in press availableEurope, GermanyUHP
DS201312-0219
2013
Green, H.W.Dobrzhinetskaya, L., Wirth, R., Green, H.W., Schreiber, A., O'Bannon, E.First find of polycrystalline diamond in ultrahigh pressure metamorphic terrane of Erzgebirge Germany.Journal of Metamorphic Geology, Vol. 31, pp. 5-18.Europe, GermanyUHP
DS201412-0985
2014
Green, H.W.Wirth, R., Dobrzhinetskaya, L., Harte, B., Schreiber, A., Green, H.W.High-Fe (Mg,Fe)O inclusion in diamond apparently from the lowermost mantle.Earth and Planetary Science Letters, Vol. 404, Oct. pp. 365-375.MantleDiamond inclusions
DS1991-0799
1991
Green, H.W. IIJin, Z.M, Green, H.W. II, Borch, R.S., Tingle, T.N.Unusual spinel garnet lherzolite xenoliths from basalts in eastern China:constraints on the late Tertiary thermal structure of the upper mantleProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 212-213ChinaLherzolite xenoliths -analyses, Geochemistry
DS1996-0370
1996
Green, H.W. IIDobrzhinetskaya, L., Green, H.W. II, Wang, S.Alpe Arami: a peridotite Massif from depths of more than 300 kilometersScience, Vol. 271, March 29, pp. 1841-45.GlobalPeridotite massif, Mantle
DS1983-0262
1983
Green, H.W.IIGreen, H.W.II, Gueguen, Y.Deformation of Peridotite in the Mantle and Extraction by Kimberlite a Case History Documented by Fluid and Solid Precipitates in Olivine.Tectonophysics, Vol. 92, No. 1-3, PP. 71-92.AustraliaPetrography
DS200712-0639
2007
Green, H.W.IILiu, L., Zhang, J., Green, H.W.II, Jin, Z., Bozhilov, K.N.Evidence of former stishovite in metamorphosed sediments, implying subduction to > 350 km.Earth and Planetary Science Letters, Vol. 263,3-4, Nov.30, pp. 180-191.MantleUHP
DS1987-0741
1987
Green, H.W.II.Tingle, T.N., Green, H.W.II.Carbon solubility in olivine: implications for upper mantle evolutionGeology, Vol. 15, No. 4, April pp. 324-326GlobalMantle genesis, Carbon
DS200512-0239
2004
Green, H.W.II.Dobrzhinetskaya, L.F., Renfro, A.P., Green, H.W.II.Synthesis of skeletal diamonds: implications for microdiamond formation in orogenic belts.Geology, Vol. 32, 10, Oct. pp. 869-872.KazakhstanUHP, C-O-H fluid, Kokchetav massif
DS200612-0340
2006
Green, H.W.II.Dobrzhinetskaya, L.F., Wirth, R., Green, H.W.II.Nanometric inclusions of carbonates in Kokchetav diamonds from Kazakhstan: a new constraint for the depth of metamorphic diamond crystallization.Earth and Planetary Science Letters, Vol. 243, 1-2, Mar. 15, pp. 85-93.Russia, KazakhstanDiamond morphology, metamorphism
DS200712-0642
2007
Green, H.W.II.Liu, X-W., Jin, Z-M., Green, H.W.II.Clinoenstatite exsolution in diopsidic augite of Dabieshan: garnet peridotite from depth of 300 km.American Mineralogist, Vol. 92, pp. 546-552.ChinaPeridotite, UHP
DS200712-1226
2007
Green, H.W.II.Zhang, J., Green, H.W.II.On the deformation of UHP eclogite: from laboratory to nature.International Geology Review, Vol. 49, 6, pp. 487-503.MantleUHP
DS200812-0430
2008
Green, H.W.II.Green, H.W.II.Are subducting zones dry below 400 km?Goldschmidt Conference 2008, Abstract p.A326.MantleSubduction
DS201212-0822
2012
Green, H.W.II.Zhao, S., Jin, Z., Zhang, J., Xu, H., Xia, G., Green, H.W.II.Does subducting lithosphere weaken as it enters the lower mantle?Geophysical Research Letters, Vol. 39, L10311 5p.MantleSubduction
DS201312-0792
2013
Green, H.W.II.Schubnel, A., Brunet, F., Hilairet, N., Gasc, J., Wang, Y., Green, H.W.II.Deep focus earthquake analogs recorded at high pressure and temperature in the laboratory.Science, Vol. 341, no. 6152, pp. 1377-1380. Sept. 20TechnologySubduction
DS1981-0187
1981
Green, J.C.Green, J.C.Geologic and Geochemical Evidence for the Nature and Development of the Precambrian Midcontinent Rift of North America.Lpi Contribution., No. 457, PP. 110-113.GlobalMid-continent
DS1982-0226
1982
Green, J.C.Green, J.C.Geology of the Keweenawan Extrusive RocksGeological Society of America (GSA) MEMOIR., No. 156, PP. 47-55.GlobalMid-continent
DS1983-0263
1983
Green, J.C.Green, J.C.Geologic and Geochemical Evidence for the Nature and Development of the Middle Proterozoic (keweenawan) Midcontinent Rift of North America.Tectonophysics, Vol. 94, PP. 413-437.GlobalMid-continent
DS1983-0264
1983
Green, J.C.Green, J.C., Brannon, J.G.Physical Volcanology of a Proterozoic Continental Rift: The keweenawan North Shore Volcanics, Minnesota.Geological Society of America (GSA), Vol. 15, No. 6, P. 586. (abstract.).GlobalMid Continent
DS1985-0248
1985
Green, J.C.Green, J.C., Chandler, V.C.Diabase Dikes of the Midcontinent Rift in Minnesota: a Record of Keweenawan Magmatism and Tectonic Development.Geological Society of America (GSA), Vol. 17, No. 7, P. 597. (abstract.).United States, Great Lakes, MinnesotaMidcontinent, Tectonics
DS1989-0355
1989
Green, J.C.Dickas, A.B., Bornhorst, T.J., Ojakangas, R.W., Green, J.C.Lake Superior basin segment of the Midcontinent rift systemAmerican Geophysical Union (AGU) 28th. International Geological Congress Field Trip Guidebook, No. T 344, 62pMidcontinentTectonics
DS1989-0539
1989
Green, J.C.Green, J.C., Fitz, T.J.Large rhyolites in the Keweenawan midcontinent rift plateau volcanics of Minnesota- lavas orrheoignimbrites?New Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 113 Abstract held June 25-July 1MinnesotaVolcanology
DS1989-1148
1989
Green, J.C.Ojakangas, R.W., Green, J.C., Holst, T.B.35th. Annual Institute on Lake Superior Geology,Proceedings andAbstracts, held Duluth Minnesota,May 4-5, 1989Institute Lake Superior Geology, 35th. VolumeMinnesota, MichiganMid continent, Tectonics
DS1991-1234
1991
Green, J.C.Nicholson, S.W., Green, J.C.Regional neodymium and lead isotopic variations among the earliest midcontinent rift basalts in western Lake SuperiorGeological Association of Canada (GAC)/Mineralogical Association of Canada/Society Economic, Vol. 16, Abstract program p. A90OntarioTectonics, Rifting
DS1992-0604
1992
Green, J.C.Green, J.C.Proterozoic rifts: North American Rift systemProterozoic Crustal Evolution, K.C. Condie, Developments in Precambrian, Chapter 3, pp. 116-119.Appalachia, OntarioTectonics, Midcontinent Rift
DS1993-0573
1993
Green, J.C.Green, J.C., Fitz, T.J.Extensive felsic lavas and rheoignimbrites in the Keweenawan Midcontinent rift plateau volcanics, Minnesota: petrographic and field recognitionJournal of Volcanology and Geothermal Research, Vol. 54, No. 3-4, January pp. 177-196MinnesotaVolcanics, Petrology
DS1995-1380
1995
Green, J.C.Ojakangas, R.W., Dickas, A.B., Green, J.C.Basement tectonics - No. 10 proceedings -prev. held 1992Kluwer Academic Publ, 450pUnited States, MidcontinentStructures, lineaments, tectonics, shear zones, Table of contents
DS1997-0247
1997
Green, J.C.Davis, D.W., Green, J.C.Geochronology of the North American Midcontinent rift in western Lake superior and implications -geodynamicsCanadian Journal of Earth Sciences, Vol. 34, No. 4, April, pp. 476-488MidcontinentGeochronology, tectonics, Geodynamics
DS1997-0868
1997
Green, J.C.Ojakangas, R.W., Diackas, A.B., Green, J.C.Middle Proterozoic to Cambrian rifting, central North AmericaGeological Society of America, SPE312, 326p. approx. $ 80.00 United StatesNorth AmericaBook - ad, Tectonics, rifting
DS1997-0869
1997
Green, J.C.Ojakangas, R.W., Dickas, A.B., Green, J.C.Middle Proterozoic to Cambrian rifting central North AmericaGeological Society of America Special Paper, No. 312, $ 100.00Appalachia, MidcontinentBook - ad, Tectonics, rifting
DS1997-1208
1997
Green, J.C.Vervoort, J.D., Green, J.C.Origin of evolved magmas in the Midcontinent rift system: ND isotope evidence for melting Archean crust.Canadian Journal of Earth Sciences, Vol. 34, No. 4, April, pp. 521-535.Minnesota, MidcontinentGeochronology, Magma
DS1983-0265
1983
Green, J.G.Green, J.G.Geologic and geochemical evidence for the nature and development of the Middle Proterozoic Keweenawan ...Tectonophysics, Vol. 94, pp; 413-37.Minnesota, Wisconsin, MidcontinentTectonics - Rifting, Geochemistry
DS1992-0460
1992
Green, J.M.Field, S.W., Haggerty, S.E., Field, J.E., Green, J.M.Symplectities in peridotites and the growth of garnet in the upper mantleEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.336South Africa, MantlePeridotite, Harzburgite
DS1985-0249
1985
Green, K.Green, K.China's Gem DiamondsThe China Business Review, May-June pp. 13-15ChinaDiamond, Production
DS1940-0176
1948
Green, L.C.Green, L.C.To the River's End #1Cape Town: Howard Timmins, 208P.Southwest Africa, Namibia, South Africa, BotswanaTravelogue, True Adventure, Diamonds, Kimberley
DS1930-0138
1933
Green, L.G.Green, L.G.The Coast of TreasureLondon: Putnam., 269P.Southwest Africa, NamibiaDiamonds, Kimberley, Occurrences
DS1930-0189
1935
Green, L.G.Green, L.G.Who Found the First Diamonds at LuderitzCape Argus, AUGUST 17TH.Southwest Africa, NamibiaHistory
DS1930-0190
1935
Green, L.G.Green, L.G.No More Diamond Raids in NamaqualandCape Argus, JUNE 8TH. P. 13.Southwest Africa, NamibiaHistory, Politics
DS1930-0216
1936
Green, L.G.Green, L.G.Secret Africa 1936London: Stanley Paul, 187P.South AfricaKimberley, History
DS1930-0245
1937
Green, L.G.Green, L.G.The Coast of DiamondsCape Town: Howard Timmins, 287P.Southwest Africa, NamibiaDiamond, Fiction, Kimberley
DS1930-0297
1939
Green, L.G.Green, L.G.Strange AfricaLondon: Stanley Paul, South AfricaKimberley, Fiction
DS1940-0114
1946
Green, L.G.Green, L.G.Secret Africa 1946London: Stanley Paul, 280P.South AfricaKimberley, History
DS1940-0115
1946
Green, L.G.Green, L.G.So Few Are FreeCape Town: Monarch House., 250P.Southwest Africa, NamibiaHistory, Kimberley
DS1940-0210
1949
Green, L.G.Green, L.G.To the River's End #2Cape Town: Harold Timmins, South AfricaHistory, Travelogue, Kimberley
DS1960-0245
1962
Green, L.G.Green, L.G.Something Rich and StrangeCape Town: Timmins, 258P.South AfricaKimberley, History
DS1960-0832
1967
Green, L.G.Green, L.G.Like Diamond Blazing; the Story of the Diamonds of South Africa and the Men Who Sought and Found and Stole Diamonds in Strange Places.London: Hale., 206P.South Africa, Southwest Africa, Namibia, PeruKalahari, Vaal River Diggings, Orange River Area, Kimberley
DS1960-0954
1968
Green, L.G.Green, L.G.Like Diamond BlazingCape Town: Struik, 295P.South AfricaHistory, Kimberley
DS2003-0497
2003
Green, M.Green, M.Crime of opportunity. In December 2000, a parcel of 21 diamonds vanished en routeCanadian Diamonds, Summer 2003, pp. 22-26.Northwest TerritoriesNews item - Sirius Diamonds
DS200412-0715
2003
Green, M.Green, M.Crime of opportunity. In December 2000, a parcel of 21 diamonds vanished en route from Yellowknife.Canadian Diamonds, Summer 2003, pp. 22-26.Canada, Northwest TerritoriesNews item - Sirius Diamonds
DS201212-0584
2012
Green, M.B.Rice, M.D., Tierney, S., O'Hagan, S., Lyons, D., Green, M.B.Knowledge, influence and firm level change: a geographic analysis of board membership associated with Canada's growing and declining businesses.Geoforum, Vol. 43, pp. 959-968.CanadaCSR - governance
DS2000-0358
2000
Green, M.G.Green, M.G., Sylvester, P.J., Buick, R.Growth and recycling of Early Archean continental crust: geochemical evidence from Pilbara Craton.Tectonophysics, Vol. 322, No. 1-2, pp. 69-88.AustraliaGeochemistry - subduction
DS1989-0365
1989
Green, N.L.Donahoe, J.L., Green, N.L., Fang, Jen-HoAn expert system for idenification of minerals in thin sectionJournal of Geology Education, Vol. 37, No. 1, pp. 4-6. Database # 17586GlobalGIS - Mineralogy, Computer- Expert system
DS1999-0295
1999
Green, N.L.Harry, D.L., Green, N.L.Slab dehydration and basalt petrogenesis in subduction systems involving very young oceanic lithosphere.Chemical Geology, Vol. 160, No. 4, Sept. 2, pp. 309-334.MantleLithosphere, Subduction
DS200612-0822
2005
Green, O.R.Lindsay, J.F., Brasier, M.D., McLoughlin, N., Green, O.R., Fogel, M., Steele, A., Mertzman, S.A.The problem of deep carbon - an Archean paradox.Precambrian Research, Vol. 143,1-4, Dec. 15, pp. 1-22.AustraliaCarbon dykes, geochronology
DS1960-0408
1963
Green, P.Turno, S.G. DI, Green, P.Diamond RiverLondon: Hamish Hamilton., 208P.VenezuelaKimberlite, Kimberley, Janlib, Travelogue
DS1989-0540
1989
Green, P.F.Green, P.F., Duddy, I.R., Leslett, G.M., Hegarty, K.A., GleadowThermal annealing of fission tracks in apatite, 4. Quantitative modelling techniques and extension to geological timescalesChemical Geology, Vol. 79, No. 2, August 1, pp. 155-GlobalGeochronology, Timescales
DS1999-0735
1999
Green, P.F.Thomson, K., Green, P.F., Whithm, A.G., Price, S.P.New constraints on the thermal history of southeast Greenland from apatite fission track analysis.Geological Society of America (GSA) Bulletin., Vol. 111, No. 7, July pp. 1054-68.GreenlandGeothermometry
DS2002-0869
2002
Green, P.F.Kohn, B.F., Green, P.F.Low temperature thermochronology: from tectonics to Lands cape evolutionTectonophysics, Vol. 349,No.1-4, pp. 1-4.GlobalGeothermometry
DS200812-1189
2008
Green, P.F.Turner, J.P., Green, P.F., Hoford, S.P., Lawrence, S.R.Thermal history of the Rio Muni (West Africa) - NE Brazil margins during continental breakup.Earth and Planetary Science Letters, Vol. 270, 3-4, pp. 354-367.Africa, West Africa, South America, BrazilGeothermometry
DS200612-0494
2006
Green, P.K.Green, P.K., Duddy, I.R.Interpretation of apatite ( U-Th) /He ages and fission track ages from cratons.Earth and Planetary Science Letters, in pressEurope, Sweden, FennoscandiaGeothermometry, geochronology
DS1991-1664
1991
Green, P.M.Stone, P., Green, P.M., Lintern, B.C., Plant, J.A., Simpson, P.R.Geochemistry characterizes provenance in southern ScotlandGeology Today, Vol. 7, No. 5, September/October pp. 177-181ScotlandGeochemistry, Geology
DS1992-0258
1992
Green, R.W.E.Cichowicz, A., Green, R.W.E.Tomographic study of upper mantle structure of the South African using wave form inversionPhysics of the Earth and Planetary Interiors, Vol. 72, No. 3-4, August pp. 276-South AfricaMantle, Geophysics -seismics
DS1992-0404
1992
Green, R.W.E.Durrheim, R.J., Green, R.W.E.A seismic refraction investigation of the Archean Kaapvaal craton, SouthAfrica, using mine tremors as the energy sourceGeophys. Journal of International, Vol. 108, No. 3, March pp. 812-832South AfricaGeophysics -seismics, Craton
DS1995-0673
1995
Green, R.W.E.Green, R.W.E., Smith, C.B., Jones, Muller, ViljoenProgress towards understanding the Kaapvaal lithosphere geophysical and geochemical perspectives.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 188-90.South AfricaGeophysics, Craton -Kaapvaal
DS1995-0674
1995
Green, R.W.E.Green, R.W.E., Webb, S.J., Wright, C.Broad band seismic studies in southern AfricaSouth Afr. Journal of Science, Vol. 91, No. 5, May pp. 234-239South AfricaGeophysics -seismics
DS1995-0675
1995
Green, R.W.E.Green, R.W.E., Webb, S.J., Wright, C.Broad band seismic studies in southern AfricaSouth Afr. Journal of Science, Vol. 91, No. 5, May pp. 234-239.South AfricaGeophysics -seismics
DS1995-1776
1995
Green, R.W.E.Smith, C.B., Green, R.W.E., Jones, M., Viljoen, K.S.Progress two ards understanding the evolution of the Kaapvaal lithosphere:the mantle perspective.Centennial Geocongress (1995) Extended abstracts, Vol. 1, p. 343-346. abstractSouth AfricaCraton, Mantle
DS1995-1998
1995
Green, R.W.E.Vinnick, L.P., Green, R.W.E., Nicolaysen, L.O.Recent deformation of the deep continental root beneath southern AfricaNature, Vol. 375, No. 6526, May 4, pp. 50-52.South Africa, BotswanaMantle, tectonics, Craton, root
DS1995-1999
1995
Green, R.W.E.Vinnik, L.P., Green, R.W.E., Nicolaysen, L.O., KosarevDeep seismic structure and kimberlites of the Kaapvaal cratonProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 656.South AfricaGeophysics -seismics, Craton -Kaapvaal
DS1996-1482
1996
Green, R.W.E.Vinnik, L.P., Green, R.W.E., Nicolaysen, L.O.Seismic constraints on dynamics of the mantle of the Kaapvaal cratonPhysics of the Earth and Planetary Interiors, Vol. 95, pp. 139-151.South AfricaGeophysics -seismics, Kaapvaal Craton
DS1996-1483
1996
Green, R.W.E.Vinnik, L.P., Green, R.W.E., Nicolaysen, L.O., Kosarev...Deep seismic structure of the Kaapvaal CratonTectonophysics, Vol. 262, No. 1-4, Sept. 30, pp. 67-75.South Africa, southern AfricaGeophysics - seismics, Craton - Kaapvaal
DS1993-1296
1993
Green, S.Rencz, A., Harris, J., Toubourg, J., Ballantye, B., Green, S.Remote sensing applications in geosciences: a an introductionProspectors and Developers Association of Canada (PDAC) Meeting Workshop held April 1, Toronto, approx. 100pGlobalBook -table of contents, Remote sensing
DS1991-1433
1991
Green, S.B.Robert, F., Sheahan, P.A., Green, S.B.Greenstone gold and crustal evolution, Nuna Conference held Val d'Or May1990Geological Association of Canada (GAC)/Mineral Deposits Division Publ, 237p. $ 25.00Quebec, Ontario, Australia, South AfricaGreenstone belt, Gold genesis
DS1981-0188
1981
Green, T.Green, T.The World of Diamonds #2Weidenfeld And Nicolson., 261P.China, South Africa, Namibia, Southwest Africa, Botswana, RussiaDiamond Industry, Marketing
DS1981-0189
1981
Green, T.Green, T.The World of Diamonds #1New York: W. Morrow And Co. Inc., 300P.GlobalKimlibkimlib
DS1996-0563
1996
Green, T.Green, T., Duval, D., Louthean, R.New frontiers in diamondsDuval Minecom, 416 470 Granville Street, Vancouver BC., 604 669-1493 Fax $ 65.00 inc. P and HGlobalBook, Anecdotes, diamond industry, companies, areas of intere
DS2001-0004
2001
Green, T.Adam, J., Green, T.Experimentally determined partition coefficients for minor and trace elements in peridotite minerals...European Journal of Mineralogy, Vol. 13, pp. 815-27.GlobalCarbonatite melt, relevance to natural Carbonatite, Microprobe ICP-MS
DS2001-0409
2001
Green, T.Green, T., Adam, J.Partition co-efficients - modeling crust-mantle... carbonatite - a popular mantle metasomatic agent.Gemoc Annual Report 2000, p. 34-5.MantleCarbonatite, Geochemistry
DS200612-0001
2006
Green, T.Adam, J., Green, T.Trace element partitioning between mica and amphibole bearing garnet lherzolite and hydrous basanitic melt: 1. experimental results and the investigation controlsContributions to Mineralogy and Petrology, Online, availableAustralia, TasmaniaPartitioning behaviour, melting
DS1990-0615
1990
Green, T.H.Guo, J.F., Green, T.H.Experimental study of barium partitioning between phlogopite and silicate liquid at upper-mantle pressure and temperatureLithos, Vol. 24, No. 2, March pp. 83-95GlobalExperimental petrology, Mantle
DS1990-0616
1990
Green, T.H.Guo, J.F., Green, T.H., O'Reilly, S.Y.Barium partitioning and anorthoclase megacryst genesisGeological Society of Australia Abstracts, No. 25, No. A12.11 pp. 239. AbstractAustraliaMagma, barium, Ba content
DS1991-0602
1991
Green, T.H.Green, T.H., Adam, J.Assessment of the garnet-clinopyroxene iron-magnesium exchange thermometer using new experimental dataJournal of Metamorphic Geology, Vol. 9, No. 3, May pp. 341-347AustraliaEclogites, Geothermetry
DS1992-0605
1992
Green, T.H.Green, T.H., Adam, ., Sie, S.H.Trace element partitioning between silicate minerals and carbonatite at 25Kbar and application to mantle MetasomatismMineralogy and Petrology, Vol. 46, No. 3, pp. 179-184MantleSilicates, Metasomatism
DS1992-0606
1992
Green, T.H.Green, T.H., Adam, J., Sie, S.Trace element partitioning and mantle Metasomatism11th. Australian Geol. Convention Held Ballarat University College, Jan., Listing of papers to be given attempting to get volAustraliaGeochemistry, Mantle
DS1993-0574
1993
Green, T.H.Green, T.H., Adam, J., Sie, S.H.Proton microprobe determined trace element partition coefficients betweenpargasite, augite and silicate of carbonatitic meltsEos, Transactions, American Geophysical Union, Vol. 74, No. 16, April 20, supplement abstract p. 340GlobalMineral chemistry, Carbonatite
DS1995-0676
1995
Green, T.H.Green, T.H.Experimental versus natural two mineral partition coefficients: a high techcontroversyInternational Geology Review, Vol. 37, No. 10, Oct. pp. 851-865GlobalPetrology -partitioning
DS1995-0677
1995
Green, T.H.Green, T.H.Significance of Niobium and Tantalum as an indicator of geochemical processes in the crust mantle systemChemical Geology, Vol. 120, No. 3-4, March 1, pp. 347-359.MantleGeochemistry -Niobium, TantaluM., Carbonatite
DS1999-0174
1999
Green, T.H.Draper, D.S., Green, T.H.P - T phase relations of silicic, alkaline, aluminous liquids: new result sand applications to mantle meltingEarth and Planetary Science Letters, Vol. 170, No. 3, July 15, pp. 255-68.MantleMelt - alkaline rocks, Metasomatism
DS1999-0175
1999
Green, T.H.Draper, D.S., Green, T.H.P T phase relations of silicic alkaline, aluminous liquids: new results and apllications to mantle meltingEarth and Planetary Science Letters, Vol. 170, No. 3, July 15, pp. 215-39.MantleMetasomatism
DS2000-0359
2000
Green, T.H.Green, T.H., Blundy, J.D., Adam, J., Yaxley, G.M.SIMS determination of trace element partition coefficients between clinopyroxene and basaltsLithos, Vol. 53, No. 3-4, Sept. 1, pp. 165-87.GlobalPetrology - experimental, Garnet
DS2000-0360
2000
Green, T.H.Green, T.H., Blundy, J.D., Adam, J., Yaxley, G.M.SIMS determination of trace element partion coefficients between garnet, clinopyroxene and basalticLithos, Vol. 53, No. 3-4, Sept. pp. 165-87.GlobalPetrology - experimental, Gpa and Temp
DS200612-0495
2006
Green, T.H.Green, T.H., Hauri, E.H., Gaetani, G.A., Adam, J.New calculations on water storage in the upper mantle, and implications for mantle melting models.Geochimica et Cosmochimica Acta, Vol. 70, 18, 1, p. 215, abstract only.MantleWater
DS200612-0548
2006
Green, T.H.Hauri, E.H., Gaetani, G.A., Green, T.H.Partitioning of water during melting of the Earth's upper mantle at H2O undersaturated conditions.Earth and Planetary Science Letters, Vol. 248, 3-4, Aug. 30, pp. 715-734.MantleMelting
DS201212-0002
2012
Green, T.H.Adam, J., Oberti, R., Camara, F., Green, T.H., Rushmer, T.The effect of water on equilibrium relations between clinopyroxenes and basanitic magmas: tracing water and non- volatile incompatible elements in the Earth's mantle.emc2012 @ uni-frankfurt.de, 1p. AbstractMantleMelting
DS1981-0190
1981
Green, T.S.Green, T.S.Diamond Diggers in Namibia Sift Ocean Sands for GemstonesSmithsonian., Vol. 12, No. 2, MAY, PP. 48-57.Southwest Africa, NamibiaHistory, Mining Methods, Littoral Diamond Placers
DS200412-2204
2004
Green, W.H.Zhang, J., Green, W.H., Bozhillov, K., Jin, Z.Faulting induced by precipitation of water at grain boundaries in hot subducting oceanic crust.Nature, Vol. 428, April 8, 633-636.MantleSubduction
DS1991-0603
1991
Green, W.V.Green, W.V., Achauer, U., Meyer, R.P.A three dimensional seismic image of the crust and upper mantle beneath the Kenya riftNature, Vol. 354, No. 6350, November 21, pp. 199-203KenyaMantle, Tectonics -rifting Kenya Rift
DS200612-0338
2006
Green II, H.W.Dobrzhinetskaya, L.F., liu, Z., Cartigny, P., Zhang, J., Tchkhetia, D., Hemley, R.J., Green II, H.W.Synchrotron infrared and Raman spectroscopy of microdiamonds from Erzgebirge, Germany.Earth and Planetary Science Letters, Vol. 248, 1-2, Aug. 15, pp. 325-334.Europe, GermanyMicrodiamonds
DS201412-0834
2014
Greenberg, E.Sinmyo, R., Pesce, G., Greenberg, E., McCammon, C., Dubrovinsky, L.Lower mantle electrical conductivity based on measurements of Al, Fe-bearing perovskite under lower mantle conditions.Earth and Planetary Science Letters, Vol. 393, pp. 165-172.MantleGeophysics
DS201805-0984
2018
Greenberg, E.Tschauner, O., Huang, S., Greenberg, E., Prakapenka, V.B., Ma, C., Rossman, G.R., Shen, A.H., Zhang, D., Newville, M., Lanzirotti, A., Tait, K.Ice-VII inclusions in diamonds: evidence for aqueous fluid in the Earth's deep mantle. Orapa, ShandongScience, Vol. 359, pp. 1136-1139.Africa, South Africa, Botswana, Congo, Sierra Leone, Chinadiamond inclusions
DS202009-1624
2020
Greenberg, E.Dorfman, S.M., Potapkin, V., Lv, M., Greenberg, E., Kupenko, I., Chumakov, A.I., Bi, W., Alp, E.E., Liu, J., Magrez, A., Dutton, S.E., Cava, R.J., McCammon, C.A., Gillet, P.Effects of composition and pressure on electronic states of iron in bridgmanite.American Mineralogist, Vol. 105, pp. 1030-1039. pdfMantleredox

Abstract: Electronic states of iron in the lower mantle's dominant mineral, (Mg,Fe,Al)(Fe,Al,Si)O3 bridgmanite, control physical properties of the mantle including density, elasticity, and electrical and thermal conductivity. However, the determination of electronic states of iron has been controversial, in part due to different interpretations of Mössbauer spectroscopy results used to identify spin state, valence state, and site occupancy of iron. We applied energy-domain Mössbauer spectroscopy to a set of four bridgmanite samples spanning a wide range of compositions: 10-50% Fe/total cations, 0-25% Al/total cations, 12-100% Fe3+/total Fe. Measurements performed in the diamond-anvil cell at pressures up to 76 GPa below and above the high to low spin transition in Fe3+ provide a Mössbauer reference library for bridgmanite and demonstrate the effects of pressure and composition on electronic states of iron. Results indicate that although the spin transition in Fe3+ in the bridgmanite B-site occurs as predicted, it does not strongly affect the observed quadrupole splitting of 1.4 mm/s, and only decreases center shift for this site to 0 mm/s at ~70 GPa. Thus center shift can easily distinguish Fe3+ from Fe2+ at high pressure, which exhibits two distinct Mössbauer sites with center shift ~1 mm/s and quadrupole splitting 2.4-3.1 and 3.9 mm/s at ~70 GPa. Correct quantification of Fe3+/total Fe in bridgmanite is required to constrain the effects of composition and redox states in experimental measurements of seismic properties of bridgmanite. In Fe-rich, mixed-valence bridgmanite at deep-mantle-relevant pressures, up to ~20% of the Fe may be a Fe2.5+ charge transfer component, which should enhance electrical and thermal conductivity in Fe-rich heterogeneities at the base of Earth's mantle.
DS202104-0590
2021
Greenberg, E.Lv, M., Dorfman, S.M., Badro, J., Borensztajin, S., Greenberg, E., Prakapenka, V.B.Reversal of carbonate-silicate cation exchange in cold slabs in Earth's lower mantle. Nature Communications, doi.org/10.10.1038 /s41467-021-21761-9 8p. PdfMantlediamond inclusions

Abstract: The stable forms of carbon in Earth’s deep interior control storage and fluxes of carbon through the planet over geologic time, impacting the surface climate as well as carrying records of geologic processes in the form of diamond inclusions. However, current estimates of the distribution of carbon in Earth’s mantle are uncertain, due in part to limited understanding of the fate of carbonates through subduction, the main mechanism that transports carbon from Earth’s surface to its interior. Oxidized carbon carried by subduction has been found to reside in MgCO3 throughout much of the mantle. Experiments in this study demonstrate that at deep mantle conditions MgCO3 reacts with silicates to form CaCO3. In combination with previous work indicating that CaCO3 is more stable than MgCO3 under reducing conditions of Earth’s lowermost mantle, these observations allow us to predict that the signature of surface carbon reaching Earth’s lowermost mantle may include CaCO3.
DS1982-0319
1982
Greenberg, J.K.Keller, G.R., Bland, A.E., Greenberg, J.K.Evidence for a Major Late Precambrian Tectonic Event (rifting?) in the Eastern Midcontinent Region, United States.Tectonics, Vol. 1, No. 2, PP. 213-223.GlobalMid-continent, Peralkaline
DS1983-0266
1983
Greenberg, J.K.Greenberg, J.K., Brown, B.A.Proterozoic Cratonization South of the Superior Province Inwisconsin.Geological Society of America (GSA), Vol. 15, No. 6, P. 586. (abstract.).Wisconsin, United States, Great LakesMid Continent
DS1984-0310
1984
Greenberg, J.K.Greenberg, J.K., Brown, B.A.Cratonic Sedimentation During the Proterozoic; an Orogenic Connection in wisconsin and the Upper Midwest.Journal of GEOLOGY, Vol. 92, No. 2, MARCH PP. 159-172.WisconsinMid-continent
DS201012-0250
2010
Greene, D.C.Greene, D.C.Neoproterozoic rifting in the southern Georgin a Basin, central Australia: implications for reconstructing Australia in Rodinia.Tectonics, Vol. 29, 5, TC5010.AustraliaGeodynamics
DS1989-0541
1989
Greene, L.C.Greene, L.C., Johnson, R.A.Interpretation of gravity and seismic relection dat a beneath the ChalbiEos, Vol. 70, No. 43, October 24, p. 1336. AbstractKenyaTectonics, Rift
DS1991-0604
1991
Greene, L.C.Greene, L.C., Richards, D.R., Johnson, R.A.Crustal structure and tectonic evolution of the Anza rift, northern SOURCE[ TectonophysicsTectonophysics, Vol. 197, No. 2-4, November pp. 203-212KenyaTectonics, Rift system
DS1981-0191
1981
Greene, R.C.Greene, R.C., Plouff, D.Location of a Caldera Source for the Soldier Meadow Tuff, Northwestern Nevada, Indicated by Gravity and Aeromagnetic Data.Geological Society of America (GSA) Bulletin., Vol. 92, No. 1, PP. 4-6, AND FICHE PP. 39-56.GlobalMid-continent, Geophysics
DS201905-1062
2019
Greene, S.Nestola, F., Jacob, D.E., Pamato, M.G., Pasqualatto, L., Oliveira, B., Greene, S., Perritt, S., Chinn, I., Milani, S., Kueter, N., Sgreva, N., Nimis, P., Secco, L., Harris, J.W.Protogenetic garnet inclusions and the age of diamonds.Geology, doi.10.1130/G45781.1Mantlediamond inclusions

Abstract: Diamonds are the deepest accessible “fragments” of Earth, providing records of deep geological processes. Absolute ages for diamond formation are crucial to place these records in the correct time context. Diamond ages are typically determined by dating inclusions, assuming that they were formed simultaneously with their hosts. One of the most widely used mineral inclusions for dating diamond is garnet, which is amenable to Sm-Nd geochronology and is common in lithospheric diamonds. By investigating worldwide garnet-bearing diamonds, we provide crystallographic evidence that garnet inclusions that were previously considered to be syngenetic may instead be protogenetic, i.e., they were formed before the host diamond, raising doubts about the real significance of many reported diamond “ages.” Diffusion modeling at relevant pressures and temperatures, however, demonstrates that isotopic resetting would generally occur over geologically short time scales. Therefore, despite protogenicity, the majority of garnet-based ages should effectively correspond to the time of diamond formation. On the other hand, our results indicate that use of large garnet inclusions (e.g., >100 ?m) and diamond hosts formed at temperatures lower than ?1000 °C is not recommended for diamond age determinations.
DS202008-1398
2020
Greene, S.Greene, S., Jacob, D.E., O'Reilly, S.Y., Henry, H., Pinter, Z., Heaman, L.Extensive prekimberlitic lithosphere modification recorded in Jericho mantle xenoliths in kimberlites, Slave Craton.Goldschmidt 2020, 1p. AbstractCanada, Northwest Territoriesdeposit - Jericho

Abstract: Wehrlite and pyroxenite xenoliths and megacrysts from the Jericho kimberlite were analyzed by ?XRF and EBSD, and for major elements, trace elements, and isotopes (Pb-Sr- O) in major phases. Thermobarometry places these samples at 60 - 180 km and 600 - 1200 ??C. While modes and textures vary, many samples have olivine-olivine grain boundaries with straight edges and 120° angle junctions, indicating granoblastic recrystallisation, while clinopyroxene and orthopyroxene are complexly intergrown. Clinopyroxene twins and subgrains recording orientations distinct from the encapsulating grain were detected using EBSD and are inferred to represent recent modification processes. Several distinct garnet compositions were measured, with multiple thin garnet rims in some samples suggesting possible successive stages of garnet crystallisation. Complex chromium zoning in garnet is detected by ?XRF in several samples (fig.1). Pb-Pb ages for most samples are similar to the age of kimberlite entrainment (173 Ma), but the shallowest pyroxenite sample preserves the most radiogenic Pb composition, intercecting concordia at 0.7 - 1.1 Ga, and is the only sample with ?18O above the mantle range (6.2±0.1 ‰). The deepest sample has the lowest ?18O (5.5±0.1 ‰) and radiogenic 87Sr/86Sr similar to MARID rocks (0.709±1 ‰). These results suggest the Jericho lithosphere experienced several melt/fluid injection events that modified substantial portions of the sampled section soon before kimberlite entrainment.
DS202105-0781
2021
Greene, S.Pamato, M.G., Novella, D., Jacobs, D.E., Oliveira, B., Pearson, D.G., Greene, S., Alfonso, J.C., Favero, M., Stachel, T., Alvaro, M., Nestola, F.Protogenetic sulfide inclusions in diamonds date the diamond formation event using Re-Os isotopes. Victor, JerichoGeology , Vol. 49, 4, 5p. Canada, Ontario, Nunavutdiamond inclusions

Abstract: Sulfides are the most abundant inclusions in diamonds and a key tool for dating diamond formation via Re-Os isotopic analyses. The manner in which fluids invade the continental lithospheric mantle and the time scale at which they equilibrate with preexisting (protogenetic) sulfides are poorly understood yet essential factors to understanding diamond formation and the validity of isotopic ages. We investigated a suite of sulfide-bearing diamonds from two Canadian cratons to test the robustness of Re-Os in sulfide for dating diamond formation. Single-crystal X-ray diffraction (XRD) allowed determination of the original monosulfide solid-solution (Mss) composition stable in the mantle, indicating subsolidus conditions of encapsulation, and providing crystallographic evidence supporting a protogenetic origin of the inclusions. The results, coupled with a diffusion model, indicate Re-Os isotope equilibration is sufficiently fast in sulfide inclusions with typical grain size, at mantle temperatures, for the system to be reset by the diamond-forming event. This confirms that even if protogenetic, the Re-Os isochrons defined by these minerals likely reflect the ages of diamond formation, and this result highlights the power of this system to date the timing of fluid migration in mantle lithosphere.
DS1982-0098
1982
Greenex, Greenbushes Tin Ltd.Birrell, R.D., Greenex, Greenbushes Tin Ltd., Territory Mining Ltd.El 2842-final Report 1981-1982Northern Territory Open File., No. CR 82-258, 8 P. UNPUBL.Australia, Northern TerritoryHeavy Minerals, Geochemistry, Diamonds, Prospecting
DS1982-0099
1982
Greenex, Greenbushes Tin Ltd.Birrell, R.D., Greenex, Greenbushes Tin Ltd., Territory Mining Ltd.El 2906 Hayes Creek Final Report 1981-1982Northern Territory Geological Survey, No. CR 82/366, 6P.Australia, Northern TerritoryProspecting, Geochemistry
DS1982-0100
1982
Greenex, Greenbushes Tin Ltd.Birrell, R.D., Greenex, Greenbushes Tin Ltd., Territory Mining Ltd.El 2842 Final Report 1981-1982Northern Territory Geological Survey Open File., No. SD5212 5069, 8P.Australia, Northern TerritoryProspecting, Heavy Mineral Sampling
DS1982-0101
1982
Greenex, Greenbushes Tin Ltd.Birrell, R.D., Greenex, Greenbushes Tin Ltd.El 3294 Hayes Creek Annual Report 1982Northern Territory Geological Survey, No. 82/365, 11P.Australia, Northern TerritoryGeochemistry, Prospecting
DS1970-0918
1974
Greenhalgh, P.Greenhalgh, P.An Economic History of the Ghanian Diamond Industry 1919-197Ph.d. Thesis, University Birmingham., 514P.Ghana, West AfricaEconomics, History
DS1985-0250
1985
Greenhalgh, P.Greenhalgh, P.West African Diamonds 1919-1983 - an Economic HistoryManchester University Press, 306P.West Africa, Ghana, Sierra LeoneProduction, Methods
DS1995-0264
1995
Greenhalgh, S.Cao, S., Greenhalgh, S.High resolution seismic tomographic delineation of ore depositsExploration Geophysics ( Australia), Vol. 26, No. 2-3, June 1, pp. 315-318AustraliaGeophysics -seismics, Tomography
DS200612-0557
2005
Greenhalgh, S.Heath, P.J., Greenhalgh, S., Direen, N.G.Modeling gravity and magnetic gradient tensor responses for exploration within the regolith.Exploration Geophysics, Vol. 36, 4, pp. 357-364.AustraliaGeophysics - not specific to diamonds
DS1989-1171
1989
Greenhalgh, S.A.Pant, D.R., Greenhalgh, S.A.Multicomponent seismic reflection profiling over an ore-body structure- a scale model investigationGeophysical Research Letters, Vol. 16, No. 10, October pp. 1089-1092GlobalGeophysics, Seismics -orebody
DS1992-0494
1992
Greenhough, J.D.Fryer, B.J., Greenhough, J.D.Evidence for mantle heterogeneity from platinum group element abundances in Indian-ocean basaltsCanadian Journal of Earth Sciences, Vol. 29, No. 11, November pp. 2329-2340IndiaMantle, Geochemistry
DS1994-0659
1994
Greenhough, J.D.Greenhough, J.D., Fryer, B.J., Owen, J.V.Mantle processes affecting the concentration and distribution of platinum group elements (PGE):information from alkaline magmas.International Symposium Upper Mantle, Aug. 14-19, 1994, Extended abstracts pp. 67-69.NewfoundlandMantle, Alkaline rocks, platinum
DS1996-0564
1996
Greenland Geological SurveyGreenland Geological SurveyGreenland MapGreenland Geological Survey, mapGreenlandMap -ad
DS1997-0442
1997
Greenland Minex News BriefGreenland Minex News BriefPlatinova A/S in the Archean of western Greenland discovers kimberliteboulders.Greenland Minex News Brief, 1/4p. and mapGreenlandNews item, Platinova A/S.
DS202108-1285
2021
Greenman, J.W.Greenman, J.W., Rooney, A.D., Patzke, M., Ielpi, A., Halverson, G.P.Re-Os geochronology highlights widespread latest Mesoproterozoic ( ca 1090-1050 Ma) cratonic basin development on northern Laurentia.Geology, Vol. 49, March pp. 779-783.Canada, Greenlandgeochronology

Abstract: The terminal Mesoproterozoic was a period of widespread tectonic convergence globally, culminating in the amalgamation of the Rodinia supercontinent. However, in Laurentia, long-lived orogenesis on its eastern margin was punctuated by short-lived extension that generated the Midcontinent Rift ca. 1110-1090 Ma. Whereas this cratonic rift basin is typically considered an isolated occurrence, a series of new depositional ages demonstrate that multiple cratonic basins in northern Laurentia originated around this time. We present a Re-Os isochron date of 1087.1 ± 5.9 Ma from organic-rich shales of the Agu Bay Formation of the Fury and Hecla Basin, which is one of four closely spaced cratonic basins spanning from northeastern Canada to northwestern Greenland known as the Bylot basins. This age is identical, within uncertainty, to ages from the Midcontinent Rift and the Amundsen Basin in northwestern Canada. These ages imply that the late Mesoproterozoic extensional episode in Laurentia was widespread and likely linked to a common origin. We propose that significant thermal anomalies and mantle upwelling related to supercontinent assembly centered around the Midcontinent Rift influenced the reactivation of crustal weaknesses in Arctic Laurentia beginning ca. 1090 Ma, triggering the formation of a series of cratonic basins.
DS1960-0553
1965
Greenman, L.Greenman, L.Preliminary Report on the Geology of the Luderitz AreaPrecamb. Res. Unit, University Cape Town , Annual Report 3rd., PP. 16-19.Southwest Africa, NamibiaGeology
DS1960-1115
1969
Greenman, L.Greenman, L.The Elizabeth Bay Formation, Luderitz, and its Bearing on The Genesis of Dolomite.Geological Society of South Africa Transactions, Vol. 72, No. 3, PP. 115-121.Southwest Africa, NamibiaGeology, Sedimentology
DS1987-0458
1987
Greenough, J.D.McHone, J.G., Ross, M.E., Greenough, J.D.Mesozoic dyke swarms of eastern North Americain: Mafic dyke swarms, editors, Halls, H.C., Fahrig, W.F., Geological, Special Paper 34, pp. 279-288GlobalQuebec- Camptonite, Monchiquite, Montregian Hills p. 28
DS1988-0267
1988
Greenough, J.D.Greenough, J.D., Hayatsu, A., Papezik, V.S.Mineralogy, petrology and geochemistry of the alkaline Malpeque Bay @Prince Edward IslandCanadian Mineralogist, Vol. 26, No. 1, March pp. 97-108GlobalBlank
DS1989-1158
1989
Greenough, J.D.Owen, J.V., Greenough, J.D., Bellefontaine, K.A.Preservation of primary geochemical signatures in polymetamorphosedtholeite: the Long Range dyke swarm,Newfoundland, CanadaLithos, Vol. 24, No. 1, December pp. 55-64NewfoundlandTholeite, Long Range dyke swarm
DS1992-0607
1992
Greenough, J.D.Greenough, J.D., Ruffman, A.Noble metal concentrations in shoshonitic lamprophyres: the Weekend Meguma terrane, Nova ScotiaGeological Association of Canada (GAC) Abstracts Volume, Vol. 17, p. A43. abstract onlyNova ScotiaShoshonite, Lamprophyre
DS1993-0575
1993
Greenough, J.D.Greenough, J.D., Owen, J.V., Ruffman, A.Noble metal concentrations in shoshonitic lamprophyres -analysis of the weekend dykes, eastern shore, Nova Scotia, Canada.Journal of Petrology, Vol. 34, No.6, December pp. 1247-1269.Nova ScotiaLamprophyres, Shoshonites
DS1993-0576
1993
Greenough, J.D.Greenough, J.D., Owen, J.V., Ruffman, A.Noble metal concentrations in shoshonitic lamprophyres: analysis of the weekend Dykes, eastern shore, Nova ScotiaJournal of Petrology, Vol. 34, No. 4, December pp. 1247-1270Nova ScotiaShoshonites, Gold, silver, platinum group elements (PGE)
DS1995-0678
1995
Greenough, J.D.Greenough, J.D., Owen, J.V.The role of subcontinental lithospheric mantle in massif type anorthositepetrogenesis:jotunitic Red BaySchweiz. Mineral. Petrogr. Mitt, Vol. 75, pp. 1-15Labrador, Quebec, UngavaProterozoic -Middle, Anorthosite -Massif-type
DS2003-0498
2003
Greenough, J.D.Greenough, J.D., Kyser, K.Contrasting Archean and Proterozoic lithospheric mantle: isotopic evidence from theContributins to Mineralogy and Petrology, Vol. 145, 2, May pp. 169-181.MontanaGeochronology - WYMAP alkaline province
DS2003-0499
2003
Greenough, J.D.Greenough, J.D., Kyser, T.K.Contrasting Archean and Proterozoic lithospheric mantle: isotopic evidence from theContributions to Mineralogy and Petrology, Vol. 145, 2, pp. 169-181.MontanaBlank
DS200412-0716
2003
Greenough, J.D.Greenough, J.D., Kyser, T.K.Contrasting Archean and Proterozoic lithospheric mantle: isotopic evidence from the Shonkin Sag sill (Montana).Contributions to Mineralogy and Petrology, Vol. 145, 2, pp. 169-181.United States, MontanaGeochronology
DS200512-0076
2005
Greenough, J.D.Benz, D.M., Fipke, C.E., Greenough, J.D.Preliminary LAM-ICP-MS analysis of diamond indicator silicate minerals in the PAnd a and New Eland kimberlite pipes.GAC Annual Meeting Halifax May 15-19, Abstract 1p.Canada, Northwest Territories, Africa, South AfricaMineral chemistry
DS200512-0365
2005
Greenough, J.D.Greenough, J.D., Dostal, J., Mallory-Greenough, L.M.Igneous rock association- pt. 4 Oceanic volcanism 1 mineralogy and petrology.Geoscience Canada, Vol. 32, 1, March pp. 29-45.MantleHotspots, tectonics, basalts
DS201805-0948
2018
Greenough, J.D.Greenough, J.D., McDivitt, J.A.Earth's evolving subcontinental lithospheric mantle: inferences from LIP continental flood basalt geochemistry.International Journal of Earth Sciences, Vol. 107, 3, pp. 787-810.Mantlegeochemistry

Abstract: Archean and Proterozoic subcontinental lithospheric mantle (SLM) is compared using 83 similarly incompatible element ratios (SIER; minimally affected by % melting or differentiation, e.g., Rb/Ba, Nb/Pb, Ti/Y) for >3700 basalts from ten continental flood basalt (CFB) provinces representing nine large igneous provinces (LIPs). Nine transition metals (TM; Fe, Mn, Sc, V, Cr, Co, Ni, Cu, Zn) in 102 primitive basalts (Mg# = 0.69-0.72) from nine provinces yield additional SLM information. An iterative evaluation of SIER values indicates that, regardless of age, CFB transecting Archean lithosphere are enriched in Rb, K, Pb, Th and heavy REE(?); whereas P, Ti, Nb, Ta and light REE(?) are higher in Proterozoic-and-younger SLM sources. This suggests efficient transfer of alkali metals and Pb to the continental lithosphere perhaps in association with melting of subducted ocean floor to form Archean tonalite-trondhjemite-granodiorite terranes. Titanium, Nb and Ta were not efficiently transferred, perhaps due to the stabilization of oxide phases (e.g., rutile or ilmenite) in down-going Archean slabs. CFB transecting Archean lithosphere have EM1-like SIER that are more extreme than seen in oceanic island basalts (OIB) suggesting an Archean SLM origin for OIB-enriched mantle 1 (EM1). In contrast, OIB high U/Pb (HIMU) sources have more extreme SIER than seen in CFB provinces. HIMU may represent subduction-processed ocean floor recycled directly to the convecting mantle, but to avoid convective homogenization and produce its unique Pb isotopic signature may require long-term isolation and incubation in SLM. Based on all TM, CFB transecting Proterozoic lithosphere are distinct from those cutting Archean lithosphere. There is a tendency for lower Sc, Cr, Ni and Cu, and higher Zn, in the sources for Archean-cutting CFB and EM1 OIB, than Proterozoic-cutting CFB and HIMU OIB. All CFB have SiO2 (pressure proxy)-Nb/Y (% melting proxy) relationships supporting low pressure, high % melting resembling OIB tholeiites, but TM concentrations do not correlate with % melting. Thus, the association of layered intrusion (plutonic CFB) TM deposits with Archean terranes does not appear related to higher metal concentrations or higher percentages of melting in Archean SLM. Other characteristics of these EM1-like magmas (e.g., S2 or O2 fugacity) may lead to element scavenging and concentration during differentiation to form ore deposits.
DS200712-0898
2006
Greenroyd, C.J.Rodger, M., Watts, A.B., Greenroyd, C.J., Peirce, C., Hobbs, R.W.Evidence for unusually thin oceanic crust and strong mantle beneath the Amazon Fan.Geology, Vol. 34, 12, pp. 1081-1084.South AmericaGeophysics - seismics
DS1970-0730
1973
Greenshields, R.Joynt, R.H., Greenshields, R., Hodgen, R.Advances in Sea and Beach Diamond Mining TechniquesMining Engineering Journal of South Africa, Vol. No. APRIL, PP. 25-49.Southwest Africa, NamibiaSubmarine Diamond Placers, Marine Diamond Corporation, Sampling
DS200812-0916
2008
Greentree, A.D.Prawer, S., Greentree, A.D.Diamond for quantum computing.Science, Vol. 320, 5883, June 20, p. 1601-2.TechnologyComputers
DS2002-0612
2002
Greenwell, B.Greenwell, B.The search for diamonds and PGMs builds momentumProspectors and Developers Association of Canada (PDAC) Exploration and, pp. 12-4.OntarioNews item - brief review, platinum group metals
DS1999-0617
1999
GreenwoodRuzicka, A., Riciputi, Taylor, Snyder, GreenwoodPetrogenesis of mantle derived sulphide inclusions in Yakutian diamonds: chemical and isotopic disequilibriuM.7th International Kimberlite Conference Nixon, Vol. 2, pp. 741-49.Russia, YakutiaQuenching from high temperatures, Deposit - Mir, 23rd., Aikhal, Udachnaya
DS1995-0679
1995
Greenwood, D.R.Greenwood, D.R., Wing, S.L.Eocene continental climates and latitudinal temperature gradientsGeology, Vol. 23, No. 11, Nov. pp. 1044-1048GlobalPaleoclimate
DS201710-2278
2017
Greenwood, D.R.Wolfe, A.P., Reyes, A.V., Royer, D.L., Greenwood, D.R., Doria, G., Gagen, M.H., Siver, P.A., Westgate, J.A.Middle Eocene CO2 and climate reconstructed from the sediment fill of a subarctic kimberlite Maar.Geology , Vol. 45, 7, pp. 619-622.Canada, Northwest Territoriesdeposit - Giraffe

Abstract: Eocene paleoclimate reconstructions are rarely accompanied by parallel estimates of CO2 from the same locality, complicating assessment of the equilibrium climate response to elevated CO2. We reconstruct temperature, precipitation, and CO2 from latest middle Eocene (ca. 38 Ma) terrestrial sediments in the posteruptive sediment fill of the Giraffe kimberlite in subarctic Canada. Mutual climatic range and oxygen isotope analyses of botanical fossils reveal a humid-temperate forest ecosystem with mean annual temperatures (MATs) more than 17 °C warmer than present and mean annual precipitation ?4× present. Metasequoia stomatal indices and gas-exchange modeling produce median CO2 concentrations of ?630 and ?430 ppm, respectively, with a combined median estimate of ?490 ppm. Reconstructed MATs are more than 6 °C warmer than those produced by Eocene climate models forced at 560 ppm CO2. Estimates of regional climate sensitivity, expressed as ?MAT per CO2 doubling above preindustrial levels, converge on a value of ?13 °C, underscoring the capacity for exceptional polar amplification of warming and hydrological intensification under modest CO2 concentrations once both fast and slow feedbacks become expressed.
DS201712-2722
2017
Greenwood, D.R.Reyes, A.V., Wolfe, A.P., Tierney, J.E., Silver, P.A., Royer, D.L., Greenwood, D.R., Buryak, S., Davies, J.H.F.L.Paleoenvironmental research on early Cenozoic sediment fills in Lac de Gras kimberlite pipes: progress and prospects.45th. Annual Yellowknife Geoscience Forum, p. 65 abstractCanada, Northwest Territoriesdeposit - Giraffe

Abstract: Several Lac de Gras kimberlite pipes host thick accumulations of stratified post-eruptive lacustrine sediment and peat. Given the range of Lac de Gras kimberlite emplacement ages, these fills - though rare - provide a unique sedimentary archive of paleoenvironments during the sustained Early Cenozoic “greenhouse” interval, in a high-latitude region otherwise devoid of Phanerozoic sediment cover. Extensive exploration drilling has provided a valuable window into this unique sedimentary record, which would have otherwise remained covered by Quaternary glacial deposits. Our focus to date has been multidisciplinary study of the Giraffe pipe sediment fill: an ~80 m-thick sequence of post-eruptive lacustrine silt overlain by peat, which paints a remarkable picture of a humid-temperate Middle Eocene forest ecosystem on the Canadian Shield. Post-eruptive chronology is provided by interbedded distal tephra horizons, likely sourced from Alaska, that have been dated by glass fission-track and zircon U-Pb techniques. Paleoclimate proxies derived from pollen, wood cellulose oxygen isotopes, and biomarkers converge on reconstructed mean annual temperatures >17 °C warmer than present, with mean winter temperatures above freezing, and mean annual precipitation ~4x present. Two independent reconstructions of CO2 from well preserved conifer foliage suggest that this warming occurred under relatively modest atmospheric CO2 concentrations of 430-630 ppm. These findings provide direct field-based evidence for dramatic past arctic warming at CO2 concentrations that were well within the range of projections under “business-as-usual” emissions scenarios, underscoring the capacity for exceptional polar amplification of climate change under modest CO2 concentrations once both fast and slow feedbacks processes become expressed. Our studies at Giraffe pipe also highlight the scientific value of archived exploration drill core in the Lac de Gras kimberlite field, particularly with respect to pipes that are unremarkable for the purpose of diamond exploration.
DS1988-0429
1988
Greenwood, H.J.Mader, U.K., Greenwood, H.J.Carbonatites and related rocks of the Prince and George Claims Northern Rocky MountainsBritish Columbia Department of Mines, Geological Fieldwork 1987, Paper 1988-1, pp. 375-380British ColumbiaBlank
DS1989-0542
1989
Greenwood, H.J.Greenwood, H.J.On models and modelingCanadian Mineralogist, Vol. 27, pt. 1, March pp. 1-14GlobalBasalt-eclogite, Petrology
DS1970-0953
1974
Greenwood, H.L.Littlejohn, A.L., Greenwood, H.L.Lherzolite Nodules in Basalts from British ColumbiaCanadian Journal of Earth Sciences, Vol. 11, PP. 1288-1308.Canada, British ColumbiaXenoliths
DS1998-0531
1998
Greenwood, J.C.Greenwood, J.C., Gibson, S.A., Thompson, R.N., WeskaPetrogenesis of Cretaceous kimberlites from the Paranatinga region, centralBrasil.7th International Kimberlite Conference Abstract, pp. 268-270.BrazilGeochemistry, petrology, Deposit - Paratinga
DS1993-1761
1993
Greenwood, P.Woodhead, J.D., Greenwood, P., Harmon, R.S., Stoffers, P.Oxygen isotope evidence for recycled crust in the source of electromagnetic-type ocean island basaltsNature, Vol. 362, No. 6423, April 29, pp. 809-813GlobalGeochronology, Ocean island basalts
DS1991-1312
1991
Greenwood, P.B.Pearson, D.G., Davies, G.R., Nixon, P.H., Greenwood, P.B.Oxygen isotope evidence for the origin of pyroxenites in the Beni Bousera peridotite massif, North Morocco: derivation from subducted oceaniclithosphereEarth and Planetary Science Letters, Vol. 102, No. 3/4, March pp. 289-301MoroccoGeochemistry, Ophiolite - Beni Bousera
DS1970-0486
1972
Greenwood, P.G.Burley, A.J., Greenwood, P.G.Geophysical Surveys over Kimberlite Pipes in LesothoInstitute of Geological Sciences GEOPHYS. DIV., I.G.S. 540 1009/72, 32P.LesothoKimberlite, Geophysics
DS1981-0192
1981
Greenwood, R.Greenwood, R., Gottliebsen, R.Cra and Ashton Crack Down on Northern MiningBusiness Review., JULY 24TH. PP. 11-12.Australia, Western AustraliaHistory, Company Investment
DS200512-0366
2004
Greff-Lefftz, M.Greff-Lefftz, M.Upwelling plumes, superswells and true polar wander.Geophysical Journal International, Vol. 159, 3, pp. 1125-1137.MantlePlume
DS200612-0778
2006
Greff-Lefftz, M.Le Mouel, J.L., Narteau, C., Greff-Lefftz, M., Holschneider, M.Dissipation at the core mantle boundary on a small scale topography.Journal of Geophysical Research, Vol. 111, 10p. B04413MantleCMB - friction
DS201012-0639
2010
Greff-Lefftz, M.Rouby, H., Greff-Lefftz, M., Besse, J.Mantle dynamics, geoid, inertia and TPW since 120 Myr.Earth and Planetary Science Letters, Vol. 292, 3-4, pp. 301-311.MantleGeodynamics
DS201412-0661
2014
Greff-Lefftz, M.Panet, I., Pajot-Metivier, G., Greff-Lefftz, M., Metivier, L., Diament, M.Mapping the mass distribution of Earth's mantle using satellite-derived gravity gradients.Nature Geoscience, Vol. 7, 2, Feb. pp. 131-135.MantleGeophysics - tomography
DS201610-1887
2016
Greff-Lefftz, M.Metivier, L., Caron, L., Greff-Lefftz, M., Pajot-Metivier, G., Fleitout, L., Rouby, H.Evidence for Post glacial signatures in gravity gradients: a clue in lower mantle viscosity. ( Hudson bay region)Earth and Planetary Science Letters, Vol. 453, pp. 146-156.Canada, OntarioGravity

Abstract: The Earth's surface was depressed under the weight of ice during the last glaciations. Glacial Isostatic Adjustment (GIA) induces the slow recession of the trough that is left after deglaciation and is responsible for a contemporary uplift rate of more than 1 cm/yr around Hudson Bay. The present-day residual depression, an indicator of still-ongoing GIA, is difficult to identify in the observed topography, which is predominantly sensitive to crustal heterogeneities. According to the most widespread GIA models, which feature a viscosity of on top of the lower mantle, the trough is approximately 100 m deep and cannot explain the observed gravity anomalies across North America. These large anomalies are therefore usually attributed to subcontinental density heterogeneities in the tectosphere or to slab downwelling in the deep mantle.
DS201805-0989
2018
Greff-Lefftz, M.Vincente de Gouveia, S., Besse, J., Frizon de Lamotte, D., Greff-Lefftz, M., Lescanne, M., Gueydan, F., Leparmentier, F.Evidence of hot spot paths below Arabia and the Horn of Africa and consequences on the Red Sea opening.Earth Planetary Science Letters, Vol. 487, pp. 210-220.Africatectonics

Abstract: Rifts are often associated with ancient traces of hotspots, which are supposed to participate to the weakening of the lithosphere. We investigated the expected past trajectories followed by three hotspots (Afar, East-Africa and Lake-Victoria) located around the Red Sea. We used a hotspot reference frame to compute their location with respect to time, which is then compared to mantle tomography interpretations and geological features. Their tracks are frequently situated under continental crust, which is known to strongly filter plume activity. We looked for surface markers of their putative ancient existence, such as volcanism typology, doming, and heat-flow data from petroleum wells. Surface activity of the East-Africa hotspot is supported at 110 Ma, 90 Ma and 30 Ma by uplift, volcanic activity and rare gas isotopic signatures, reminiscent of a deep plume origin. The analysis of heat-flow data from petroleum wells under the Arabian plate shows a thermal anomaly that may correspond to the past impact of the Afar hotspot. According to derived hotspot trajectories, the Afar hotspot, situated (at 32 Ma) 1000 km north-east of the Ethiopian-Yemen traps, was probably too far away to be accountable for them. The trigger of the flood basalts would likely be linked to the East-Africa hotspot. The Lake-Victoria hotspot activity appears to have been more recent, attested only by Cenozoic volcanism in an uplifted area. Structural and thermal weakening of the lithosphere may have played a major role in the location of the rift systems. The Gulf of Aden is located on inherited Mesozoic extensional basins between two weak zones, the extremity of the Carlsberg Ridge and the present Afar triangle, previously impacted by the East-Africa hotspot. The Red Sea may have opened in the context of extension linked to Neo-Tethys slab-pull, along the track followed by the East Africa hotspot, suggesting an inherited thermal weakening.
DS1999-0262
1999
Gregersen, S.Gregersen, S., et al.Important findings expected from Europe's largest seismic arrayEos, Vol. 80, No. 1, Jan. 5, pp. 1, 6.EuropeGeophysics - seismics
DS200412-0406
2004
Gregersen, S.Darbyshire, F.A., Larsen, T.B., Mosegaard, K., Dahl Jensen, T., Gudmundsson, O., Bach, T., Gregersen, S., PedeA first detailed look at the Greenland lithosphere and upper mantle; using Rayleigh wave tomography.Geophysical Journal International, Vol. 158, 1, pp. 267-286.Europe, GreenlandGeophysics - seismic
DS200612-1491
2006
Gregersen, S.Voss, P., Mosegaard, K., Gregersen, S., TORThe Tornquist Zone, north east inclining lithospheric transition at the south western margin of the Baltic Shield: revealed through a nonlinear teleseismic tomographic inversion.Tectonophysics, Vol. 416, 1-4, April 5, pp. 151-166.Europe, Baltic ShieldGeophysics - seismics
DS2000-0478
2000
Gregg, J.M.Keller, T.J., Gregg, J.M., Shelton, K.L.Fluid migration and associated diagenesis in the Greater Reelfoot Rift region Midcontinent United StatesGeological Society of America (GSA) Bulletin., Vol. 112, No. 11, Nov. pp. 1680-93.Arkansas, MidcontinentCraton, Rifting - not specific to diamonds
DS201212-0260
2012
Gregg, P.M.Gregg, P.M., De Silva, S.L., Grosfils, E.B., Parmigiani, J.P.Catastrophic caldera forming eruptions: thermomechanics and implications for eruption triggering and maximum caldera dimensions on Earth.Journal of Volcanology and Geothermal Research, Vol. 242-242, pp. 1-12.MantleCalderas
DS201605-0885
2016
Gregg, P.M.Pritchard, M.E., Gregg, P.M.Enigmatic relationship between silicic and volcanic and plutonic rocks: geophysical evidence for silicic crustal melt in the continents: where. What kind, and how much?Elements, Vol. 12, pp. 121-127.TechnologyGeophysics
DS1993-0577
1993
Gregg, W.J.Gregg, W.J.Structural geology of parautochthonous and allochthonous terranes of Penokean Orogeny comparisons with Northern Appalachian tectonicsUnited States Geological Survey (USGS) Bulletin, No. B 1904 -Q, 28p. $ 2.50MichiganStructure, Baraga Belt
DS1993-0578
1993
Gregg, W.J.Gregg, W.J.Structural geology of parautochthonous and allochthonous terranes of the Penokean OrogenyU.s. Geological Survey Bulletin, No. 1904, 26pMichiganTectonics, Penokean Orogeny
DS1999-0263
1999
Greggs, D.H.Greggs, D.H., Hein, F.J.Lineaments and basement tectonics in the Western Canada sedimentary basin8th. Calgary Mining forum, 1p. abstractSaskatchewan, AlbertaCraton, Tectonics - lineaments
DS2001-0758
2001
GregoireMcInnes, B.I.A., Gregoire, Binss, Herzig, HanningtonHydrous metasomatism of oceanic sub arc mantle: petrology, geochemistry of fluid metasom. mantle wedgeEarth and Planetary Science Letters, Vol. 188, No. 1, May 30, pp.169-83.Papua New GuineaXenoliths, Metasomatism - not specific to diamonds
DS2001-0788
2001
GregoireMoine, B., Gregoire, Cottin, Sheppard, O'Reilly, GiretVolatile bearing ultramafic to mafic xenoliths from the Kerugelen Archipelago: evidence for carbonatites...Journal of South African Earth Sciences, Vol. 32, No. 1, p. A 25. (abs)Indian Ocean, mantleCarbonatite, Kerugelen Archipelago
DS1993-0422
1993
Gregoire, D.C.Evans, N.J., Gregoire, D.C.Use of platinum group elements for impactor identification terrestrial impact craters and Cretaceous Tertiary boundaryGeochimica et Cosmochimica Acta, Vol. 57, No.15, pp. 3737-3748GlobalImpact craters, platinum group elements (PGE)
DS1994-0497
1994
Gregoire, D.C.Evans, N.J., Gregoire, D.C., Goodfellow, W.D., Miles, N., VeizerThe Cretaceous Tertiary fireball layer, ejecta layer and coal seam: platinum group elements (PGE) content and mineralogy of size fractionsUnknown, pp. 223-235Alberta, Italy, New Zealand, Denmark, Colorado, WyomingPlatinum Group Elements, K-T boundary
DS1999-0325
1999
Gregoire, M.Ionov, D.A., Gregoire, M., Prikhodko, V.S.Feldspar Ti Oxide metasomatism in off cratonic continental and oceanic upper mantle.Earth and Planetary Science Letters, Vol.165, No.1, Jan.15, pp.37-44.MantleMetasomatism
DS2001-0410
2001
Gregoire, M.Gregoire, M., Jackson, I., O'Reilly, S.Y., Cottin, J.Y.The lithospheric mantle beneath Kerguelen Islands: petrological and petrophysical characteristics....Contributions to Mineralogy and Petrology, Vol. 142, No. 2, Nov. pp. 244-59.Indian Ocean, Kerguelen IslandsMantle mafic rock types - correlation with profiles, Geophysics - seismics
DS2001-0411
2001
Gregoire, M.Gregoire, M., McInnes, B.I.A., O'Reilly, S.Y.Hydrous metasomatism of oceanic sub-arc mantle, Pt. 2. trace element characteristics of slab derived fluids.Lithos, Vol. 59, No. 3, Nov. pp. 91-108.Papua New GuineaMantle metasomatism -Lihir
DS2002-0613
2002
Gregoire, M.Gregoire, M., Bell, D.R., Le Roex, A.P.Trace element geochemistry of phlogopite rich mafic mantle xenoliths: their classification and relationshipContributions to Mineralogy and Petrology, Vol. 142, No. 5, Feb. pp. 603-25.MantlePeridotites, kimberlites - phlogopite bearing, Kimberlites
DS2002-1295
2002
Gregoire, M.Rabinowicz, M., Ricard, Y., Gregoire, M.Compaction in a mantle with a very small melt concentration: implications for theEarth and Planetary Science Letters, Vol. 203, 1, pp. 205-220.MantleMagmatism, Carbonatite, Geochemistry
DS2003-0094
2003
Gregoire, M.Bell, D.R., Gregoire, M., Grove, T.L., Chatterjee, N.D., Bowring, S.A.Silica and carbon deposition in Kimberley peridotites8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, AbstractSouth AfricaMantle petrology, Deposit - Bultfontein
DS2003-0292
2003
Gregoire, M.Coussaert, N., Gregoire, M., Mercier, J.C.C., Bell, D.R., Demaiffe, D., Le RoexThe origin of clinopyroxene in cratonic mantle8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractSouth AfricaMantle geochemistry, Deposit - Bultfontein, Jagersfontein, Monastery, Premie
DS2003-0500
2003
Gregoire, M.Gregoire, M., Bell, D.R., LeRoex, A.P.Garnet lherzolites from the Kaapvaal Craton ( South Africa): trace element evidence forJournal of Petrology, Vol. 44, 4, pp. 629-58.South AfricaMineralogy, Metasomatism
DS200412-0127
2003
Gregoire, M.Bell, D.R., Gregoire, M., Grove, T.L., Chatterjee, N.D., Bowring, S.A.Silica and carbon deposition in Kimberley peridotites.8 IKC Program, Session 6, AbstractAfrica, South AfricaMantle petrology Deposit - Bultfontein
DS200412-0437
2004
Gregoire, M.Delpech, G., Gregoire, M., O'Reilly, S.Y., Cottin, J.Y., Moine, B., Michon, G., Giret, A.Feldspar from carbonate rich silicate metasomatism in the shallow oceanic mantle under Kerguelen Islands ( South Indian Ocean).Lithos, Vol. 75, 1-2, July pp. 209-237.Kerguelen IslandsMetasomatism, trace element fingerprinting, petrogeneti
DS200412-0717
2003
Gregoire, M.Gregoire, M., Bell, D.R., LeRoex, A.P.Garnet lherzolites from the Kaapvaal Craton ( South Africa): trace element evidence for a metasomatic history.Journal of Petrology, Vol. 44,4,pp. 629-58.Africa, South AfricaMineralogy Metasomatism
DS200412-1173
2004
Gregoire, M.Lorand, J.P., Delpech, G., Gregoire, M., Moine, B., O'Reilly, S.Y., Cottin, J.Y.Platinum group elements and the multistage metasomatic history of Kerguelen lithospheric mantle ( South Indian Ocean).Chemical Geology, Vol. 208, 1-4, pp. 195-215.Indian OceanMetasomatism, carbonatite
DS200412-1349
2004
Gregoire, M.Moine, B.N., Gregoire, M., O'Reilly, S.Y., Delpech, G., Sheppard, S.M.F., Lorand, J.P., Renac, Giret, CottinCarbonatite melt in oceanic upper mantle beneath the Kerguelen Archipelago.Lithos, Vol. 75, pp. 239-252.Kerguelen IslandsCarbonatite, harzburgite, metasomatism
DS200512-0367
2005
Gregoire, M.Gregoire, M., Tinguely, C., Bell, D.R., Le Roex, A.P.Spinel lherzolite xenoliths from the Premier kimberlite ( Kaapvaal craton) South Africa: nature and evolution of the shallow upper mantle beneath Bushveld Complex.Lithos, Vol. 84, 3-4, Oct. pp. 185-205.Africa, South AfricaPetrology - Premier, melting, metasomatism
DS200612-0115
2005
Gregoire, M.Bell, D.R., Gregoire, M., Grove, T.L., Chaterjee, N., Carlson, R.W., Buseck, P.R.Silica and volatile element metasomatism of Archean mantle: a xenolith scale example from the Kaapvaal Craton.Contributions to Mineralogy and Petrology, Vol. 150, 3, pp. 251-267.Africa, South AfricaMetasomatism
DS200612-0496
2005
Gregoire, M.Gregoire, M., Rabonowicz, M., Janse, A.J.A.Mantle mush compaction: a key to understand the mechanisms of concentration of kimberlite melts and initiation of swarms of kimberlite dykes.Journal of Petrology, Vol. 47, 3, March, pp. 631-646,Africa, South Africa, Lesotho, BotswanaConvection, Kimberley, Rietfontein, Central Cape,Gibeon
DS200612-1086
2006
Gregoire, M.Petitjean, S., Rabinowicz, M., Gregoire, M., Chevrot, S.Differences between Archean and Proterozoic lithospheres: assessment of the possible major role of thermal conductivity.Geochemistry, Geophysics, Geosystems: G3, Vol. 7, Q03021 10.1029/2005 GC001053MantleGeothermometry
DS200712-0196
2007
Gregoire, M.Coltorti, M., Bonadiman, C., Faccini, B., Gregoire, M., OReilly, S.Y., Powell, W.Amphiboles from supra subduction and intraplate lithospheric mantle.Lithos, Vol. 99, 1-2, pp. 68-84.MantleSubduction
DS200812-0046
2008
Gregoire, M.Arndt, N.T., Coltice, N., Helstaedt, H., Gregoire, M.Origin of Archean subcontinental lithospheric mantle: some petrological constraints.Lithos, In press available 47p.CanadaArchean - craton
DS200812-0230
2008
Gregoire, M.Coltori, M., Gregoire, M.Metasomatism in oceanic and continental lithospheric mantle: introduction.Geological Society of London, Special Publications no. 293, pp. 1-10.MantleMetasomatism
DS200912-0122
2009
Gregoire, M.Coltorti, M., Downes, H., Gregoire, M., O'Reilly, S.Y., Beccaluva, L., Bonadiman, Piccardo.Rivalenti, SienaPetrological evolution of the European lithospheric mantle: from Archean to present day.Journal of Petrology, Vol. 50, no. 7, pp. 1181-1184.MantleMagmatism
DS200912-0763
2008
Gregoire, M.Tinguely, C.E., Gregoire, M., LeRoex, A.P.Eclogite and pyroxenite xenoliths from off craton kimberlites near the Kaapvaal Craton, South Africa.Comptes Rendus Geoscience, Vol. 340, 12, pp. 811-812.Africa, South AfricaMineral chemistry
DS201012-0114
2010
Gregoire, M.Coltori, M., Downes, H., Gregoire, M., O'Reilly, S.Y.Petrological evolution of the European lithospheric mantle: introduction.Geological Society of London Special Publication, No. 337, pp. 1-5.EuropeMantle petrology
DS201012-0115
2009
Gregoire, M.Coltori, M., Gregoire, M.One page overview of papers in Elements August 2010, p. 268. papers from this book are not listed.Metasomatism in oceanic and continental lithospheric mantle, Geological Society Special Publication, 293, 361p.MantleBook - mantle metasomatism
DS201312-0713
2013
Gregoire, M.Poitrasson, F., Delpech, G., Gregoire, M.On the iron isotope heterogeneity of lithospheric mantle xenoliths: implications for mantle metasomatism, the origin of basalts and the iron isotope composition of the Earth.Contributions to Mineralogy and Petrology, Vol. 165, 6, pp. 1243-1258.Africa, Cameroon, South AfricaMelting
DS201509-0396
2015
Gregoire, M.France, L., Chazot, G., Kornprobst, J., Dallai, L., Vannucci, R., Gregoire, M., Bertrand, H., Boivin, P.Mantle refertilization and magmatism in old orogenic regions: the role of late-orogenic pyroxenites.Lithos, Vol. 232, pp. 49-75.Africa, Morocco, Cameroon, Jordan, Europe, FranceXenoliths

Abstract: Pyroxenites and garnet pyroxenites are mantle heterogeneities characterized by a lower solidus temperature than the enclosing peridotites; it follows that they are preferentially involved during magma genesis. Constraining their origin, composition, and the interactions they underwent during their subsequent evolution is therefore essential to discuss the sources of magmatism in a given area. Pyroxenites could represent either recycling of crustal rocks in mantle domains or mantle originated rocks (formed either by olivine consuming melt-rock reactions or by crystal fractionation). Petrological and geochemical (major and trace elements, Sr-Nd and O isotopes) features of xenoliths from various occurrences (French Massif-Central, Jordan, Morocco and Cameroon) show that these samples represent cumulates crystallized during melt percolation at mantle conditions. They formed in mantle domains at pressures of 1-2 GPa during post-collisional magmatism (possibly Hercynian for the French Massif-Central, and Panafrican for Morocco, Jordan and Cameroon). The thermal re-equilibration of lithospheric domains, typical of the late orogenic exhumation stages, is also recorded by the samples. Most of the samples display a metasomatic overprint that may be either inherited or likely linked to the recent volcanic activity that occurred in the investigated regions. The crystallization of pyroxenites during late orogenic events has implications for the subsequent evolution of the mantle domains. The presence of large amounts of mantle pyroxenites in old orogenic regions indeed imparts peculiar physical and chemical characteristics to these domains. Among others, the global solidus temperature of the whole lithospheric domain will be lowered; in turn, this implies that old orogenic regions are refertilized zones where magmatic activity would be enhanced.
DS201709-1998
2017
Gregoire, M.Henry, H., Afonso, J.C., Satsukawa, T., Griffin, W.L., O'Reilly, S.Y., Kaczmarek, M-A., Tilhac, R., Gregoire, M., Ceuleneer, G.The unexplored potential impact of pyroxenite layering on upper mantle seismic properties.Goldschmidt Conference, abstract 1p.Europe, Spain, United States, Californiageophysics - seismics

Abstract: It is now accepted that significant volumes of pyroxenites are generated in the subduction factory and remain trapped in the mantle. In ophiolites and orogenic massifs the geometry of pyroxenite layers and their relationships with the host peridotite can be observed directly. Since a large part of what is known about the upper mantle structure is derived from the analysis of seismic waves, it is crucial to integrate pyroxenites in the interpretations. We modeled the seismic properties of a peridotitic mantle rich in pyroxenite layers in order to determine the impact of layering on the seimsic properties. To do so, EBSD data on deformed and undeformed pyroxenites from the Cabo Ortegal complex (Spain) and the Trinity ophiolite (California, USA) respectively are combined with either A or B-type olivine fabrics in order to model a realistic pyroxenite-rich upper mantle. Consideration of pyroxeniterich domains within the host mantle wall rock is incorporated in the calculations using the Schoenberg and Muir group theory [1]. This quantification reveals the complex dependence of the seismic signal on the deformational state and relative abundance of each mineral phase. The incorporation of pyroxenites properties into geophysical interpretations in understanding the lithospheric structure of subduction zones will lead to more geologically realistic models.
DS202002-0219
2020
Gregoire, M.Tilhac, R., Oliveira, B., Griffin, W.L., O'Reilly, S.Y., Schaefer, B.F., Alard, O., Ceuleneer, G., Afonso, J.C., Gregoire, M.Reworking of old continental lithosphere: unradiogenic Os and decoupled Hf-Nd isotopes in sub-arc mantle pyroxenites.Lithos, Vol. 354-355, 19p. pdfEurope, Spainpyroxenites

Abstract: Mantle lithologies in orogenic massifs and xenoliths commonly display strikingly different Hf- and Nd-isotope compositions compared to oceanic basalts. While the presence of pyroxenites has long been suggested in the source region of mantle-derived magmas, very few studies have reported their combined HfNd isotope compositions. We here report the first LuHf data along with ReOs data and S concentrations on the Cabo Ortegal Complex, where the pyroxenite-rich Herbeira massif has been interpreted as remnants of a delaminated arc root. The pyroxenites, chromitites and their host harzburgites show a wide range of whole-rock 187Re/188Os and 187Os/188Os (0.16-1.44), indicating that Re was strongly mobilized, partly during hydrous retrograde metamorphism but mostly during supergene alteration that preferentially affected low-Mg#, low Cu/S pyroxenites. Samples that escaped this disturbance yield an isochron age of 838 ± 42 Ma, interpreted as the formation of Cabo Ortegal pyroxenites. Corresponding values of initial 187Os/188Os (0.111-0.117) are relatively unradiogenic, suggesting limited contributions of slab-derived Os to primitive arc melts such as those parental to these pyroxenites. This interpretation is consistent with radiogenic Os in arc lavas being mostly related to crustal assimilation. Paleoproterozoic to Archean Os model ages confirm that Cabo Ortegal pyroxenites record incipient volcanic arc magmatism on the continental margin of the Western African Craton, as notably documented by zircon UPb ages of 2.1 and 2.7 Ga. LuHf data collected on clinopyroxene and amphibole separates and whole-rock samples are characterized by uncorrelated 176Lu/177Hf and 176Hf/177Hf (0.2822-0.2855), decoupled from Nd-isotope compositions. This decoupling is ascribed to diffusional disequilibrium during melt-peridotite interaction, in good agreement with the results of percolation-diffusion models simulating the interaction of an arc melt with an ancient melt-depleted residue. These models notably show that HfNd isotopic decoupling such as recorded by Cabo Ortegal pyroxenites and peridotites (??Hf(i) up to +97) is enhanced during melt-peridotite interaction by slow diffusional re-equilibration and can be relatively insensitive to chromatographic fractionation. Finally, we discuss the hypothesis that arc-continent interaction may provide preferential conditions for such isotopic decoupling and propose that its ubiquitous recognition in peridotites reflects the recycling of sub-arc mantle domains derived from ancient, reworked SCLM.
DS202008-1413
2020
Gregoire, M.Le Roex, A., Tinguely, C., Gregoire, M.Eclogite and garnet pyroxenite xenoliths from kimberlites emplaced along the southern margin of the Kaapvaal craton, southern Africa: mantle or lower crustal fragments?Journal of Petrology, https://doi.org/ 10.1093/petrology /egaa040 50p. PdfAfrica, South Africakimberlites

Abstract: Eclogite xenoliths, together with garnet pyroxenites and some mafic garnet granulites, found in kimberlites located along the southern margin of the Kaapvaal craton in southern Africa have been analysed by electron microprobe and mass spectrometry techniques to determine their geochemical characteristics. The majority of eclogites are bimineralic with garnet and omphacitic clinopyroxene in subequal proportions, with rutile as the main accessory phase; a few contain kyanite. Based on K2O in clinopyroxene and Na2O in garnet, the eclogites can be classified as Group II eclogites, and the majority are high-Ca in character. Garnet pyroxenites comprise garnet clinopyroxenites and garnet websterites. Major and trace element concentrations and isotope ratios of reconstituted bulk rock compositions of the eclogites and garnet pyroxenites allow constraints to be placed on depth of origin and likely protolith history. Calculated Fe–Mg exchange equilibration temperatures for the eclogites range from 815 to 1000?°C, at pressures of 1·7?±?0·4?GPa as determined by REE partitioning, indicating that they were sampled from depths of 50–55?km; i.e. within the lower crust of the Namaqua–Natal Belt. The garnet pyroxenites show slightly lower temperatures (686–835?°C) at similar pressures of equilibration. Initial 143Nd/144Nd and 87Sr/86Sr ratios (calculated to time of kimberlite emplacement) of both lithologies overlap the field for lower crustal samples from the Namaqua–Natal Belt. Further evidence for a crustal origin is found in the similar REE patterns shown by many of the associated garnet granulite xenoliths. Garnet pyroxenites are interpreted to have a similar origin as the associated eclogites but with the mafic protolith having insufficient Na (i.e. low modal plagioclase) to allow for development of omphacitic pyroxene. Metamorphism of the mafic protoliths to these eclogites and garnet pyroxenites is inferred to have occurred during crustal shortening and thickening associated with the collision of the Namaqua–Natal Belt with the Kaapvaal craton at 1–1·2?Ga.
DS202009-1639
2020
Gregoire, M.Le Roex, A., Tinguely, C., Gregoire, M.Eclogite and garnet pyroxenite xenoliths from kimberlites emplaced along the southern margin of the Kaapvaal Craton, southern Africa: mantle or lower crustal fragments?Journal of Petrology, pp. 1-32. pdf.Africa, South Africaeclogite, pyroxenite

Abstract: Eclogite xenoliths, together with garnet pyroxenites and some mafic garnet granulites, found in kimberlites located along the southern margin of the Kaapvaal craton in southern Africa have been analysed by electron microprobe and mass spectrometry techniques to determine their geochemical characteristics. The majority of eclogites are bimineralic with garnet and omphacitic clinopyroxene in subequal proportions, with rutile as the main accessory phase; a few contain kyanite. Based on K2O in clinopyroxene and Na2O in garnet, the eclogites can be classified as Group II eclogites, and the majority are high-Ca in character. Garnet pyroxenites comprise garnet clinopyroxenites and garnet websterites. Major and trace element concentrations and isotope ratios of reconstituted bulk rock compositions of the eclogites and garnet pyroxenites allow constraints to be placed on depth of origin and likely protolith history. Calculated Fe-Mg exchange equilibration temperatures for the eclogites range from 815 to 1000?°C, at pressures of 1•7?±?0•4?GPa as determined by REE partitioning, indicating that they were sampled from depths of 50-55?km; i.e. within the lower crust of the Namaqua-Natal Belt. The garnet pyroxenites show slightly lower temperatures (686-835?°C) at similar pressures of equilibration. Initial 143Nd/144Nd and 87Sr/86Sr ratios (calculated to time of kimberlite emplacement) of both lithologies overlap the field for lower crustal samples from the Namaqua-Natal Belt. Further evidence for a crustal origin is found in the similar REE patterns shown by many of the associated garnet granulite xenoliths. Garnet pyroxenites are interpreted to have a similar origin as the associated eclogites but with the mafic protolith having insufficient Na (i.e. low modal plagioclase) to allow for development of omphacitic pyroxene. Metamorphism of the mafic protoliths to these eclogites and garnet pyroxenites is inferred to have occurred during crustal shortening and thickening associated with the collision of the Namaqua-Natal Belt with the Kaapvaal craton at 1-1•2?Ga.
DS201112-0198
2010
Gregoirue, M.Coltori, M., Downes, H., Gregoirue, M., O'Reilly, S.Y.,editorsPetrological evolution of the European lithospheric mantle.Geological Society of London, Special Publ., 337, 246p.MantleBook - review
DS1992-0608
1992
Gregor, B.Gregor, B.Some ideas on the rock cycle: 1788-1988Geochimica et Cosmochimica Acta, Vol. 56, No. 8, pp. 2993-3000GlobalGeologic theory, Cyclic views
DS1997-0443
1997
Gregori, D.A.Gregori, D.A., Bjerg, E.A.New evidence on the nature of frontal Cordillera ophiolitic belt -ArgentinaJournal of South American Earth Sciences, Vol. 10, No. 2, pp. 147-156ArgentinaOphiolites
DS200712-0779
2007
GregorieNeumann, E.R., Simon, N.S.C., Bonadiman, C., Coltorti, Delpech, GregorieExtremely refractory oceanic lithospheric mantle and its implications for geochemical mass balance.Plates, Plumes, and Paradigms, 1p. abstract p. A712.MantleHarzburgite
DS200612-0835
2006
Gregorie, M.Lorand, J-P., Gregorie, M.Petrogenesis of base metal sulphide assemblages of some peridotites from the Kaapvaal Craton (South Africa).Contributions to Mineralogy and Petrology, Vol. 151, 5, May pp. 521-538.Africa, South AfricaKimberlites, whole rock geochemistry
DS200912-0013
2009
Gregorie, M.Arndt, N.T., Coltice, N., Helmstaedt, H., Gregorie, M.Origin of Archean subcontinental lithospheric mantle: some petrological constraints.Lithos, Vol. 109, 1-2, pp. 61-71.MantlePetrology
DS1997-0488
1997
GregoryHausel, W.D., Kucera, R.E., McCandless, T.E., GregoryDiamond exploration potential of the Wyoming craton, western USA ... extends into southernmost Alberta.Wyom. Geol. Association Guidebook, No. 48, pp. 139-176.Alberta, Wyoming, SaskatchewanCraton - brieg mention of Wyoming province
DS1998-0597
1998
GregoryHausel, W.D., Kucera, R.E., McCandless, T.E., GregoryMantle derived diatremes in the southern Green River Basin, Wyoming, USA7th International Kimberlite Conference Abstract, pp. 320-1.WyomingDiatremes, Deposit - Cedar Mountain
DS201706-1115
2017
Gregory, C.J.Zi, J-W., Gregory, C.J., Rasmussen, B., Sheppard, S., Muhling, J.R.Using monazite geochronology to test the plume model for carbonatites: the example of Gifford Creek carbonatite complex, Australia.Chemical Geology, Vol. 463, pp. 50-60.Australiacarbonatite

Abstract: Carbonatites are carbonate-dominated igneous rocks derived by low-degree partial melting of metasomatized mantle, although the geodynamic processes responsible for their emplacement into the crust are disputed. Current models favor either reactivation of lithospheric structures in response to plate movements, or the impingement of mantle plumes. Geochronology provides a means of testing these models, but constraining the age of carbonatites and related metasomatic events is rarely straightforward. We use in situ U-Th-Pb analysis of monazite by SHRIMP to constrain the emplacement age and hydrothermal history of the rare earth element-bearing Gifford Creek Carbonatite Complex in Western Australia, which has been linked to plume magmatism at ca. 1075 Ma. Monazite in carbonatites and related metasomatic rocks (fenites) from the carbonatite complex dates the initial emplacement of the carbonatite at 1361 ± 10 Ma (n = 22, MSWD = 0.91). The complex was subjected to multiple stages of magmatic/hydrothermal overprinting from ca. 1300 Ma to 900 Ma during later regional tectonothermal events. Carbonatite emplacement at ca. 1360 Ma appears to be an isolated igneous event in the region, and occurred about 300 million years before intrusion of the ca. 1075 Ma Warakurna large igneous province, thus precluding a genetic connection. The Gifford Creek Carbonatite Complex occurs within a major crustal suture, and probably formed in response to reactivation of this suture during plate reorganization. Our study demonstrates the veracity of monazite geochronology in determining the magmatic and hydrothermal histories of a carbonatite complex, critical for evaluating competing geodynamic models for carbonatites. The approach involving in situ SHRIMP U-Th-Pb dating of monazite from a wide spectrum of rocks in a carbonatite complex is best suited to establishing the intrusive age and hydrothermal history of carbonatites.
DS201708-1587
2017
Gregory, C.J.Zi, J-W., Gregory, C.J., Rasmussen, B., Sheppard, S., Muhling, J.R.Using monazite geochronology to test the plume model for carbonatites: the example of Gifford Creek carbonatite complex, Australia.Chemical Geology, Vol. 463, pp. 50-60.Australiacarbonatites, Gifford Creek

Abstract: Carbonatites are carbonate-dominated igneous rocks derived by low-degree partial melting of metasomatized mantle, although the geodynamic processes responsible for their emplacement into the crust are disputed. Current models favor either reactivation of lithospheric structures in response to plate movements, or the impingement of mantle plumes. Geochronology provides a means of testing these models, but constraining the age of carbonatites and related metasomatic events is rarely straightforward. We use in situ U-Th-Pb analysis of monazite by SHRIMP to constrain the emplacement age and hydrothermal history of the rare earth element-bearing Gifford Creek Carbonatite Complex in Western Australia, which has been linked to plume magmatism at ca. 1075 Ma. Monazite in carbonatites and related metasomatic rocks (fenites) from the carbonatite complex dates the initial emplacement of the carbonatite at 1361 ± 10 Ma (n = 22, MSWD = 0.91). The complex was subjected to multiple stages of magmatic/hydrothermal overprinting from ca. 1300 Ma to 900 Ma during later regional tectonothermal events. Carbonatite emplacement at ca. 1360 Ma appears to be an isolated igneous event in the region, and occurred about 300 million years before intrusion of the ca. 1075 Ma Warakurna large igneous province, thus precluding a genetic connection. The Gifford Creek Carbonatite Complex occurs within a major crustal suture, and probably formed in response to reactivation of this suture during plate reorganization. Our study demonstrates the veracity of monazite geochronology in determining the magmatic and hydrothermal histories of a carbonatite complex, critical for evaluating competing geodynamic models for carbonatites. The approach involving in situ SHRIMP U-Th-Pb dating of monazite from a wide spectrum of rocks in a carbonatite complex is best suited to establishing the intrusive age and hydrothermal history of carbonatites.
DS1984-0311
1984
Gregory, E.Gregory, E.Constraints on Kimberlite Magma Ascent TimeUniversity WYOMING 1984 ROCKY MOUNTAIN GEO DAYS SYMPOSIUM, HELD A, PP. 5-7.United States, State Line, Colorado, WyomingGenesis
DS1988-0292
1988
Gregory, E.B.Hausel, W.D., Sutherland, W.M., Gregory, E.B.Stream-sediment sample results in search of kimberlite intrusives in southeastern WyomingUnited States Geological Survey (USGS) Open File, No. 88-11, 11p. Map 1: 100, 000WyomingGeochemistry, Sampling-Stream-sediment
DS1960-1116
1969
Gregory, G.P.Gregory, G.P.Geochemical Dispersion Patterns Related to Kimberlite Intrusives in North America.Ph.d. Thesis, University of London, Royal School of Mines, 327P.United States, Gulf Coast, ArkansasGeochemistry
DS1960-1117
1969
Gregory, G.P.Gregory, G.P., Tooms, J.S.Geochemical Prospecting for KimberlitesCol. Sch. Mines Quarterly, Vol. 64, No. 1, JANUARY PP. 265-304.United States, Gulf Coast, ArkansasGeochemistry, Evaluation, Prairie Creek, Mineral Chemistry, Soil
DS1981-0193
1981
Gregory, G.P.Gregory, G.P., Seltrust mining corp. pty. ltd.Tr 7668h Alice Hill Diamond Exploration Dixon Range SheetWest Australia Geological Survey Open File., No. GSWA 1199 ROLL 403, M 2712, 27P.Australia, Western AustraliaProspecting, Photogeology, Stream Sediment Sampling
DS1982-0227
1982
Gregory, G.P.Gregory, G.P., Mason, M.G., Pedler, A.D., Williams, S.D.Argyle Diamond Deposit Western AustraliaConfidential Report In-house., JULY 6TH. 5P.Australia, Western AustraliaGeology, Petrology, Mineralogy
DS1982-0298
1982
Gregory, G.P.Jaques, A.L., Gregory, G.P., Lewis, J.D., Ferguson, J.The Ultrapotassic Rocks of the West Kimberley Region, Western Australia, and a New Class of Diamondiferous Kimberlite.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, PP. 251-252, (abstract.).AustraliaKimberlite, Leucite, Lamproite, Ellendale, Calwynyardah, Noonkanb
DS1984-0312
1984
Gregory, G.P.Gregory, G.P.Exploration for Primary Diamond Deposits with Special Emphasis on the Lennard Shelf, W.a. #2Bp Minerals Australia In House Report., UNPUBL. 16P.Australia, Western AustraliaProspecting
DS1984-0313
1984
Gregory, G.P.Gregory, G.P.Exploration for Primary Diamond Deposits with Special Emphasis on the Lennard Shelf, Western Australia. #1In: The Canning Basin., PP. 475-484.Australia, Western AustraliaProspecting, Sampling, Geochemistry, Geophysics, Remote Sensing
DS1984-0380
1984
Gregory, G.P.Jaques, A.L., Lewis, J.D., Smith, C.B., Gregory, G.P., Ferguson.The Diamond Bearing Ultrapotassic Lamproitic Rocks of the West Kimberley Region Western Australia.Proceedings of Third International Kimberlite Conference, Vol. 1, PP. 225-254.AustraliaLamproite, Geochronology, Ellendale, Calwynyardah, Noonkanbah
DS1989-0543
1989
Gregory, G.P.Gregory, G.P., White, D.R.Collection and treatment of diamond exploration samples #2Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 2, pp. 1123-1134AustraliaExploration, Geochemistry-sampling
DS1992-0609
1992
Gregory, G.P.Gregory, G.P., Janse, A.J.A.Diamond exploration in tropical terrainsin: Regolith exploration geochemistry in tropical and subtropical, Elsevier, ChapterV.1, pp. 419-437Australia, AfricaGeochemistry, Diamond exploration tropics
DS202009-1643
2020
Gregory, G-M.Nabyl, Z., Massuyeau, M.,Gaillard, F., Tuduri, J., Gregory, G-M., Trong, E., Di Carlo, I., Melleton, J., Bailly, L. A window in the course of alkaline magma differentiation conducive to immiscible REE-rich carbonatite.Geochimica et Cosmochimica Acta, Vol. 282, pp. 297-323.Africa, East Africacarbonatites

Abstract: Rare earth element (REE) enrichments in carbonatites are often described as resulting from late magmatic-hydrothermal or supergene processes. However, magmatic pre-enrichment linked to the igneous processes at the origin of carbonatites are likely to contribute to the REE fertilisation. Experimental constraints reveals that immiscibility processes between carbonate and silicate melts can lead to both REE enrichments and depletions in carbonatites making the magmatic processes controlling REE enrichments unclear. We link REE contents of carbonatites to the magmatic stage at which carbonatites are separated from silicate magma in their course of differentiation. We present results of experiments made at pressure and temperature conditions of alkaline magmas and associated carbonatites differentiation (0.2-1.5 GPa; 725-975?°C; FMQ to FMQ?+?2.5), simultaneously addressing crystal fractionation of alkaline magmas and immiscibility between carbonate (calcio-carbonate type) and silicate melts (nephelinite to phonolite type). The experimental data shows that the degree of differentiation, controlling the chemical composition of alkaline melts, is a key factor ruling the REE concentration of the coexisting immiscible carbonate melts. In order to predict carbonate melt REE enrichments during alkaline magma differentiation, we performed a parameterisation of experimental data on immiscible silicate and carbonate melts, based exclusively on the silica content, the alumina saturation index and the alkali/alkaline-earth elements ratio of silicate melts. This parameterisation is applied to more than 1600 geochemical data of silicate magmas from various alkaline provinces (East African Rift, Canary and Cape Verde Islands) and show that REE concentrations of their potential coeval carbonatite melts can reach concentration ranges similar to those of highly REE enriched carbonatites (?REE?>?30 000?ppm) by immiscibility with phonolitic/phono-trachytic melt compositions, while more primitive alkaline magmas can only be immiscible with carbonatites that are not significantly enriched in REE.
DS1910-0502
1916
Gregory, H.E.Gregory, H.E.Garnet Deposits of the Navajo Reservation, Arizona and UtahEconomic Geology, Vol. 11, PP. 223-230.United States, Arizona, Utah, Colorado PlateauPetrology
DS1910-0528
1917
Gregory, H.E.Gregory, H.E.Geology of the Navajo Country: a Reconnaissance of Parts Ofarizaona, New Mexico and Utah.United States Geological Survey (USGS) PROF. PAPER., No. 93, PP. 93-95; P. 102; PP. 146-147.United States, New Mexico, Utah, Colorado PlateauGeology
DS1860-0066
1868
Gregory, J.R.Gregory, J.R.Diamonds from the Cape of Good Hope Orange RiverGeology Magazine (London), Dec. 1, Vol. 5, No. 12, PP. 558-561.Africa, South Africa, Cape ProvinceHistory
DS1860-0085
1869
Gregory, J.R.Gregory, J.R.Discovery of Diamonds at the Cape Orange and Vaal riversGeology Magazine (London), Dec. 1, Vol. 6, PP. 333-334.Africa, South Africa, Cape ProvinceHistory
DS1996-0167
1996
Gregory, K.J.Branson, J., Brown, A.K., Gregory, K.J.Global continental changes: the context of paleohydrologyGeological Society of London, No. 115, 280p. approx. $98.00 United StatesGlobalPaleohydrology, Book -ad
DS1992-0236
1992
Gregory, K.M.Chase, C.G., Gregory, K.M., Butler, R.F.Geologic constraints on amounts of Colorado Plateau rotationEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 95Colorado PlateauPaleomagnetics, Tectonics
DS200612-0497
2006
Gregory, L.C.Gregory, L.C., Meert, J.G., Pradhan, V., Pandit, M.K., Tamrat, E., Malone, S.J.A paleomagnetic and geochronologic study of the Majhgawan kimberlite. India: implications for the age of the Upper Vindhyan Supergroup.Precambrian Research, Vol. 149, 1-2, pp. 65-75.IndiaDeposit - Majhgawan, geophysics, geochronology
DS201012-0596
2010
Gregory, L.C.Pradhan, V.R., Meert, J.G., Pandit, M.K., Kamenov, G., Gregory, L.C., Malone, S.J.India's changing place in global Proterozoic reconstructions: a review of geochronologic constraints and paleomagnetic poles from the Dharwar Bundelk hand and MarwarJournal of Geodynamics, Vol. 50, 3-4, pp. 224-242.IndiaCraton, crustal evolution
DS201412-0248
2015
Gregory, L.C.Foster, D.A., Goscombe, B.D., Newstead, B., Mapani, B., Mueller, P.A., Gregory, L.C., Muvangua, E.U-Pb age and Lu-Hf isotopic dat a of detrital zircons from the Neoproterozoic Damara sequence: implications for Congo and Kalahari before Gondwana.Gondwana Research, Vol. 28, 1, pp. 179-190.AfricaGeochronology
DS1986-0303
1986
Gregory, P.G.Gregory, P.G., White, D.R.Collection and treatment of diamond exploration samples, #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 460-462AustraliaDiamond exploration
DS1992-0684
1992
Gregory, R.H.Hausel, H.D., Marlatt, G.G., Nielson, E.L., Gregory, R.H.Preliminary study of metals and precious stones along the Union Pacific right of way, southern WyomingWyoming Geological Survey Open File Report, No. 92-5, 79pWyomingDiamonds mentioned
DS1984-0314
1984
Gregory, R.T.Gregory, R.T., Taylor, H.P.Jr.Non Equilibrium 18 O 16 O Effects in Mantle XenolithsGeological Society of America (GSA), Vol. 16, No. 6, P. 524. (abstract.).GlobalGeothermometry
DS1986-0304
1986
Gregory, R.T.Gregory, R.T., Taylor, H.P.Jr.Possible non-equilibrium oxygen isotope effects in mantlenodules, an alternative to the Kyser O'Neil Carmichael 18O16geothermometerContributions to Mineralogy and Petrology, Vol. 93, No. 1, pp. 114-119GlobalGeothermometry
DS1986-0305
1986
Gregory, R.T.Gregory, R.T., Taylor, H.P.Jr.Non-equilibrium metasomatic 18 O/16 effects in upper mantlemineralassemblagesContributions to Mineralogy and Petrology, Vol. 93, No. 1, pp. 124-135GlobalMantle
DS1987-0728
1987
Gregory, R.T.Taylor, H.P..Jr., Gregory, R.T., Turi, B.Oxygen-18/Oxygen-16 evidence for fluid rock interaction in the uppermantle: dat a from ultramafic nodules and potassium rich volcanic rocks inItalyNato, Ser. C., Chemical Transp. Metasomatic processes, Vol. 218, pp. 1-37ItalyPeridotite nodule basalt, kimberlite, Inclusions
DS1999-0300
1999
Gregory, R.W.Hausel, D., Gregory, R.W.Geology, diamond potential, geochemistry, and geophysics Iron Mountain kimberite district.Geology and mineral of Wyoming, Oct. 14, 15. abstract pp. 25-26.WyomingGrant Creek, Eagle Rock, Geophysics - em, mag
DS2001-0459
2001
Gregory, R.W.Hausel, W.D., Gregory, R.W., Moten, R.H., Sutherland, W.M.Economic geology of the Iron Mountain kimberlite district, WyomingWyoming Geological Association Guidebook, No. 51, pp. 151-164.WyomingGeology - Iron Mountain
DS201906-1270
2019
Gregory, S.P.Barnett, M.J., Deady, E.A., Gregory, S.P., Palumbo-Roe, B.The role of biobased circular economy approach in sustainable critical metal extraction: the rare earth elements. Bioleaching3rd International Critical Metals Meeting held Edinburgh, Apr. 30-May 2.GlobalREE

Abstract: PDF link to presentation.
DS1960-0246
1962
Gregory, Sir.T.Gregory, Sir.T.Ernest Oppenheimer and the Economic Development of Southernafrica. #1London: Oxford University Press, Southwest Africa, Namibia, South AfricaDiamond, Politics, Biography, Kimberley
DS1960-0247
1962
Gregory, T.E.Gregory, T.E.Ernest Oppenheimer and the Economic Development of Southernafrica. #2Cape Town: Oxford University Press, 637P.South AfricaHistory, Kimberley
DS201912-2821
2019
Gregoryanz, E.Sanatmaria-Perez, D., Ruiz-Fuertes, J., Pena-Alvarez, M., Chulia-Jordan, R., Marquerno, T., Zimmer, D., Guterrez-Cano, V., Macleod, S., Gregoryanz, E., Popescue, C., Rodriguez-Herandez, P., Munoz, A.Post-tilleyite, a dense calcium silicate carbonate phase.Nature Scientific Reports, Vol. 9, 11p. PdfMantletilleyite

Abstract: Calcium carbonate is a relevant constituent of the Earth’s crust that is transferred into the deep Earth through the subduction process. Its chemical interaction with calcium-rich silicates at high temperatures give rise to the formation of mixed silicate-carbonate minerals, but the structural behavior of these phases under compression is not known. Here we report the existence of a dense polymorph of Ca5(Si2O7)(CO3)2 tilleyite above 8 GPa. We have structurally characterized the two phases at high pressures and temperatures, determined their equations of state and analyzed the evolution of the polyhedral units under compression. This has been possible thanks to the agreement between our powder and single-crystal XRD experiments, Raman spectroscopy measurements and ab-initio simulations. The presence of multiple cation sites, with variable volume and coordination number (6-9) and different polyhedral compressibilities, together with the observation of significant amounts of alumina in compositions of some natural tilleyite assemblages, suggests that post-tilleyite structure has the potential to accommodate cations with different sizes and valencies.
DS2002-0034
2002
Gregory-Wodzicki, K.M.Anders, M.H., Gregory-Wodzicki, K.M., Spiegelman, M.A critical evaluation of Late Tertiary accelerated uplift rates for the eastern Cordillera, central AndesJournal of Geology, Vol.110,1,pp. 89-100.BoliviaTectonics
DS1991-0605
1991
Gregotski, M.E.Gregotski, M.E., Jensen, O., Arkani-Hamed, J.Fractal stochastic modeling of aeromagnetic dataGeophysics, Vol. 56, No. 11, November pp. 1706-1715Alberta, OntarioGeophysics, Athabaska Basin, Kirkland Lake
DS201705-0834
2017
Greiff, S.Hilgner, A., Greiff, S., Quast, D.Gemstones in the first millennium AD. Mines, trade, workshops and symbolism. Romisch-Germanisches Zentralmuseum Leibniz-Forschungsinstitut fur Archaologie Mainz International Conference Oct. 20-22, 2015, pp. 155-217.GlobalBook - gemstones
DS1989-0544
1989
Greig, A.Greig, A., Nicholls, I.A.Thermal histories of Victorian peridotite xenolithsNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 114 Abstract held June 25-July 1AustraliaAnakie cone, Xenoliths
DS1992-0610
1992
Greig, A.Greig, A., Nicholls, I., Sie, S.Metasomatism of the upper mantle by melts: a proton microprobe study11th. Australian Geol. Convention Held Ballarat University College, Jan., AbstractAustraliaMantle, Microprobe
DS1996-0911
1996
Greig, A.McBride, J.S., Lambert, D.D., Greig, A., Nicholls, I.A.Multistage evolution of Australian subcontinental mantle: Rhenium- Osmium (Re-Os) isotopic constraints from Victorian...Geology, Vol. 24, No. 7, July pp. 631-634.Australia, VictoriaMantle xenoliths, Geochronology
DS2003-0682
2003
Greig, A.Kamber, B.S., Greig, A., Schoenberg, R., Collerson, K.D.A refined solution to Earth's hidden niobium: implications for evolution of continentalPrecambrian Research, Vol. 126, 3-4, Oct. pp.289-308.MantleGeochemistry - niobium
DS200412-0943
2003
Greig, A.Kamber, B.S., Greig, A., Schoenberg, R., Collerson, K.D.A refined solution to Earth's hidden niobium: implications for evolution of continental crust and mode of core formation.Precambrian Research, Vol. 126, 3-4, Oct. pp.289-308.MantleGeochemistry - niobium
DS201112-1119
2011
Greig, A.Woodhead, J., Hergt, J., Greig, A., Edwards, L.Subduction zone Hf anomalies: mantle messenger, melting artefact or crustal process?Earth and Planetary Science Letters, Vol. 304, 1-2, pp. 231-239.MantleSubduction
DS201312-0314
2013
Greig, A.Giuliani, A., Phillips, D., Kendrick, M.K., Maas, R., Greig, A., Armstrong, R., Felgate, M.R., Kamenetsky, V.S.Dating mantle metasomatism: a new tool ( U/PB LIMA Titanate) and an imposter ( 40Ar/39Ar phlogopite).Goldschmidt 2013, AbstractMantleMetasomatism
DS201412-0296
2014
Greig, A.Giuliani, G., Phillips, D., Maas, R., Woodhead, J.D., Kendrick, M.A., Greig, A., Armstrong, R.A., Chew, D., Kamenetsky, V.S., Fiorentini, M.I.LIMA U-Pb ages link lithospheric mantle metasomatism to Karoo magmatism beneath the Kimberley region, South Africa.Earth and Planetary Science Letters, Vol. 401, pp. 132-147.Africa, South AfricaKimberlite
DS201803-0450
2014
Greig, A.Giuliani, A., Phillips, D., Maas, R., Woodhead, J.D., Kendrick, M.A., Greig, A., Armstrong, R.A., Chew, D., Kamenetsky, V.S., Fiorentini, M.L.LIMA U-Pb ages link lithospheric mantle metasomatism to Karoo magmatism beneath the Kimberley region, South Africa.Earth and Planetary Science Letters, Vol. 401, pp. 132-147.Africa, South Africametasomatism

Abstract: The Karoo igneous rocks (174-185 Ma) of southern Africa represent one of the largest continental flood basalt provinces on Earth. Available evidence indicates that Karoo magmas either originated in the asthenosphere and were extensively modified by interaction with the lithospheric mantle prior to emplacement in the upper crust; or were produced by partial melting of enriched mantle lithosphere. However, no direct evidence of interaction by Karoo melts (or their precursors) with lithospheric mantle rocks has yet been identified in the suites of mantle xenoliths sampled by post-Karoo kimberlites in southern Africa. Here we report U-Pb ages for lindsleyite-mathiasite (LIMA) titanate minerals (crichtonite series) from three metasomatised, phlogopite and clinopyroxene-rich peridotite xenoliths from the ?84 Ma Bultfontein kimberlite (Kimberley, South Africa), located in the southern part of the Karoo magmatic province. The LIMA minerals appear to have formed during metasomatism of the lithospheric mantle by fluids enriched in HFSE (Ti, Zr, Hf, Nb), LILE (K, Ba, Ca, Sr) and LREE. LIMA U-Pb elemental and isotopic compositions were measured in situ by LA-ICP-MS methods, and potential matrix effects were evaluated by solution-mode analysis of mineral separates. LIMA minerals from the three samples yielded apparent U-Pb ages of , and (). A single zircon grain extracted from the ?190 Ma LIMA-bearing sample produced a similar U-Pb age of , within uncertainty of the LIMA ages. These data provide the first robust evidence of fluid enrichment in the lithospheric mantle beneath the Kimberley region at ?180-190 Ma, and suggest causation of mantle metasomatism by Karoo melts or their precursor(s). The results further indicate that U-Pb dating of LIMA minerals provides a new, accurate tool for dating metasomatic events in the lithospheric mantle.
DS201908-1773
2019
Greig, A.Bussweiler, Y., Giuliani, A., Greig, A., Kjarsgaard, B.A., Petts, D., Jackson, S.E., Barrett, N., Luo, Y., Pearson, D.G.Trace element analysis of high-Mg olivine by LA-ICP-MS - characterization of natural olivine standards for matrix-matched calibration and application to mantle peridotites.Chemical Geology, Vol. 524, pp. 136-157.Mantleperidotite

Abstract: The trace element composition of olivine is becoming increasingly important in petrological studies due to the ubiquity of olivine in the Earth's upper mantle and in primitive magmatic rocks. The LA-ICP-MS method allows for the routine analysis of trace elements in olivine to sub-ppm levels, but a major drawback of this method is the lack of knowledge about possible downhole fractionation effects when non matrix-matched calibration is used. In this contribution, we show that matrix-matched (i.e., olivine-based) calibration is preferable for small laser spot sizes (<100??m) due to significant laser-induced inter-element fractionation between olivine and commonly used silicate glass calibration materials, e.g., NIST SRM 612, GSD-1G and BHVO-2G. As a result, we present two Mg-rich natural olivine standards (355OL and SC-GB) that have been characterized by independent methods (EPMA, solution ICP-MS), and by LA-ICP-MS in four different laboratories. These natural olivines have been used 1) as primary standards for the matrix-matched calibration of olivine samples for most elements of interest (e.g., Li, Na, Al, P, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn), and 2) as secondary standards to assess the accuracy of results. Comparison of olivine- and silicate glass-calibrated results for natural peridotitic olivine reveals that matrix-matched calibration is essential when using small laser spot sizes (<100??m) in order to mitigate downhole fractionation effects for certain elements, especially Na, P, Mn, Co, Ni and Zn. If matrix-matched calibration is not feasible, we recommend that spot sizes of ?100??m, laser fluence of ?4.0?J/cm2, and total laser shot counts of ?250 (e.g., 5?Hz repetition rate for 50?s) are used in order to minimize fractionation effects between olivine and silicate glass calibration materials. We demonstrate the applicability of matrix-matched calibration on olivine from a suite of different mantle peridotite xenoliths sampled by kimberlites and alkali basalts from on-craton and off-craton localities.
DS1993-1128
1993
Greig, A.G.Nicholls, I.A., Greig, A.G., Gray, C.M., Price, R.C.Newer volcanics province- basalts, xenoliths and megacrystsAustralia Geological Survey AGSO, Record No. 1993/58, $ 16.95AustraliaNewer Volcanics, Xenoliths
DS201704-0627
2017
Greig, J.Greig, J., Besserer, D., Raffle, K.Exploring forgotten diamond-bearing ground in the North Slave Craton. Muskox and JerichoVancouver Kimberlite Cluster, Apr. 5, 1p. AbstractCanada, NunavutDeposit - Jericho
DS1996-0659
1996
Greiling, R.Hynes, A., Arkani-Hamed, J., Greiling, R.Subduction of continental margins and the uplift of high pressure metamorphic rocksEarth and Planetary Science Letters, Vol. 140, No. 1-4, May 1, pp. 13-26GlobalTectonics, Subduction -metamorphism
DS1998-0472
1998
Greiling, R.O.Garfunkel, Z., Greiling, R.O.A thin orogenic wedge upon thick foreland lithosphere and the missing foreland basin.Geol. Rundsch., Vol. 87, pp. 314-25.Scandinavia, Norway, Sweden, FinlandTectonics, Collisional orogen
DS201810-2336
2018
Greiling, R.O.Kankeu, B., Greiling, R.O., Nzenti, J.P., Ganno, S., Danguene, P.Y.E., Basshahak, J., Hell, J.V.Contrasting Pan-African structural styles at the NW margin of the Congo shield in Cameroon.Journal of African Earth Sciences, Vol. 146, pp. 28-47.Africa, Camerooncraton

Abstract: Field, microstructural, and anisotropy of magnetic susceptibility (AMS, magnetic fabrics) studies assessed the Pan-African deformational history and strain geometry at the southern margin of the Central African Fold Belt (CAFB) against the older, cratonic basement of the Congo Shield (CS). Reflected light microscopy and thermomagnetic studies supported the identification of magnetic minerals. Data cover a low angle thrust margin (Mbengis-Sangmelima area) in the east and high angle shear zones cutting the margin (Kribi area) in the west, at the Atlantic coast. In the CS basement units, magnetic anisotropy is generally higher than in the low grade Pan-African units. In the latter, early D1/D2 shortening produced a flat-lying magnetic foliation parallel with the regional trend of the belt, a shallow magnetic lineation, and mostly oblate fabrics. Subsequent D3 deformation is only of local importance in the Mbengis-Sangmelima area. The magnetic lineation shows distinct maxima in NNE-SSW direction, parallel with the low angle tectonic transport direction. In the Kribi area, the NNE-SSW trending Kribi-Campo shear zone (KCSZ) affected both older rocks and Pan-African high grade metapelites of the Yaoundé unit together with their basal thrust. The early planar fabric (S1) was overprinted during D2 folding under relatively high T conditions, and subsequent D3 wrenching. Magnetic fabrics document a progressive change from oblate towards prolate ellipsoids towards the KCSZ. Magnetic foliations with medium to steep dips curve into the N-S to NE-SW orientation of the KCSZ, lineations follow the same trend with shallow to medium plunges. This fabric implies that the KCSZ is a Pan-African strike-slip shear zone with a subordinate component of compression. Strike-slip tectonics in the west (KCSZ) and thrusting in the east imply N-S to NE-SW convergence during Pan-African terrane assembly against the present northern margin of the CS. In addition, the KCSZ may separate the CS from the São Francisco Craton in Brazil and thus be the northern part of a link connecting the CAFB to the West Congo Belt in the south. This putative Pan-African link separated the São Francisco Craton from the Congo Shield prior to Mesozoic Gondwana break-up.
DS1999-0264
1999
Greiner, B.Greiner, B.Euler rotations in plate tectonic reconstructionsComputers and Geosciences, Vol. 25, No. 3, pp. 209-216.GlobalTectonics, Euler application - not specific to diamonds
DS1988-0268
1988
Greiner, N.R.Greiner, N.R., Phillips, D.S., Johnson, J.D., Volk, F.Diamonds in detonation sootNature, Vol. 333, No. 6172, June 2, pp. 440-441GlobalBlank
DS1990-0150
1990
Greiner, R.Badziag, P., Verwoerd, W.S., Ellis, W.P., Greiner, R.Nanometre-sized diamonds are more stable than graphiteNature, Vol. 343, No. 6255, Jan. 18, pp. 244-245GlobalDiamond crystallography
DS2002-0096
2002
Greiner Mai, H.Ballani, L., Greiner Mai, H., Stromeyer, D.Determining the magnetic field in the core mantle boundary zone by non-harmonic downward continuation.Geophysical Journal International, Vol.149,2,pp.374-89., Vol.149,2,pp.374-89.MantleGeophysics - magnetics, Boundary
DS2002-0097
2002
Greiner Mai, H.Ballani, L., Greiner Mai, H., Stromeyer, D.Determining the magnetic field in the core mantle boundary zone by non-harmonic downward continuation.Geophysical Journal International, Vol.149,2,pp.374-89., Vol.149,2,pp.374-89.MantleGeophysics - magnetics, Boundary
DS201902-0261
2019
Grenholm, M.Baratoux, L., Soderlund, U., Ernst, R.E., de Roever, E., Jessell, M.W., Kamo, S., Naba, S., Perrouty, S., Metelka, V., Yatte, D., Grenholm, M., Diallo, D.P., Ndiaye, P.M., Dioh, E., Cournede, C., Benoit, M., Baratoux, D., Youbi, N., Rousse, S., BendaoudNew U-Pb baddeleyite ages of mafic dyke swarms of the West African and Amazonian cratons: implication for their configuration in supercontinents through time.Dyke Swarms of the World: a modern perspective, Srivastava et al. eds. Springer , pp. 263-314.Africa, West Africa, South Americageochronology

Abstract: Eight different generations of dolerite dykes crosscutting the Paleoproterozoic basement in West Africa and one in South America were dated using the high precision U-Pb TIMS method on baddeleyite. Some of the individual dykes reach over 300 km in length and they are considered parts of much larger systems of mafic dyke swarms representing the plumbing systems for large igneous provinces (LIPs). The new U-Pb ages obtained for the investigated swarms in the southern West African Craton (WAC) are the following (oldest to youngest): 1791?±?3 Ma for the N010° Libiri swarm, 1764?±?4 Ma for the N035° Kédougou swarm, 1575?±?5 for the N100° Korsimoro swarm, ~1525-1529 Ma for the N130° Essakane swarm, 1521?±?3 Ma for the N90° Sambarabougou swarm, 915?±?7 Ma for the N070° Oda swarm, 867?±?16 Ma for the N355° Manso swarm, 202?±?5 Ma and 198?±?16 Ma for the N040° Hounde swarm, and 200?±?3 Ma for the sills in the Taoudeni basin. The last ones are related to the Central Atlantic Magmatic Province (CAMP) event. The Hounde swarm is oblique to the dominant radiating CAMP swarm and may be linked with the similar-trending elongate Kakoulima intrusion in Guinea. In addition, the N150° Käyser swarm (Amazonian craton, South America) is dated at 1528?±?2 Ma, providing a robust match with the Essakane swarm in a standard Amazonia-West African craton reconstruction, and resulting in a combined linear swarm >1500 km by >1500 km in extent. The Precambrian LIP barcode ages of c. 1790, 1765-1750, 1575, 1520, 915. 870 Ma for the WAC are compared with the global LIP record to identify possible matches on other crustal blocks, with reconstruction implications. These results contribute to the refinement of the magmatic ‘barcode’ for the West African and Amazonian cratons, representing the first steps towards plausible global paleogeographic reconstructions involving the West African and Amazonian cratons.
DS1989-0545
1989
Grenne, T.Grenne, T.Magmatic evolution of the Lokken SSZ ophiolite,Norwegian Caledonides:relationships between anomalous lavas and high-level intrusionsGeol. Journal, Vol. 24, pp. 251-274NorwayOphiolite, Geochemistry
DS1996-1435
1996
Grenne, T.Tontti, M., Gautneb, H., Grenne, T., et al.Map of ore deposits in central FennoscandiaFinland Geological Survey Map, 1: 1, 000, 000FinlandMetallogeny, Deposits
DS200812-0483
2008
Grenon, H.Holmes, P.K., Grenon, H., Self, M.V., Pell, J., Neilson, S.The Chidliak property, a new diamond district on Baffin Island, Nunavut.Northwest Territories Geoscience Office, p. 35. abstractCanada, Nunavut, Baffin IslandBrief overview - Peregrine
DS200912-0310
2009
Grenon, H.Holmes, P., Pell, J., Clements, B., Grenon, H., Sell, M.The Chidliak diamond project, Baffin Island, one year after initial discovery.37th. Annual Yellowknife Geoscience Forum, Abstracts p. 24.Canada, Nunavut, Baffin IslandHistory
DS201212-0295
2012
Grenon, H.Herman, L.M., Grutter, H.S., Pell, J., Holmes, P., Grenon, H.U-Pb geochronology , SR and ND isotope compositions of groundmass perovskite from the Chidliak and Qilaq kimberlites, Baffin Island, Nunavut.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, Nunavut, Baffin IslandDeposit - Chidliak, Qilaq
DS201212-0515
2012
Grenon, H.Neilson, S., Grutter, H., Pell, J., Grenon, H.The evolution of kimberlite indicator mineral interpretation on the Chidliak project, Baffin Island, Nunavut.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, Nunavut, Baffin IslandDeposit - Chidliak
DS201212-0548
2012
Grenon, H.Pell, J., Grutter, H., Grenon, H., Dempsey, S., Neilson, S.Exploration and discovery of the Chidliak kimberlite province, Baffin Island, Nunavut: Canada's newest diamond district.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractCanada, Nunavut, Baffin IslandDeposit - Chidliak
DS201312-0695
2013
Grenon, H.Pell, J., Clements, B., Grutter, H., Neilson, S., Grenon, H.Following kimberlite indicator minerals to source in the Chidliak kimberlite province, Nunavut.PDAC 2013 , 6p.Canada, Nunavut, Baffin IslandIndicator Mineralogy
DS201312-0696
2013
Grenon, H.Pell, J., Clements, B., Grutter, H., Neilson, S., Grenon, H.Following kimberlite indicator minerals to source in the Chidliak kimberlite province, Nunavut.GSC Open file 7374 Ftp2.cits.rncan.gc.ca, pp. 47-52.Canada, Nunavut, Baffin IslandDeposit - Chidliak
DS201412-0670
2013
Grenon, H.Pell, J., Grutter, H., Neilson, S., Lockhart, G., Dempsey, S., Grenon, H.Exploration and discovery of the Chidliak kimberlite province, Baffin Island, Nunavut: Canada's newest diamond district.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, pp. 209-228.Canada, Nunavut, Baffin IslandDeposit - Chidliak area
DS200512-0671
2005
Grenvold, K.MacPherson, C.G., Hilton, D.R., Day, J.M., Lowry, D., Grenvold, K.High 3He 4He depleted mantle and low 180 recycled oceanic lithosphere in the source of central Iceland magmatism.Physics and Planetary Science Letters, Vol. 233, 3-4, pp. 411-427.MantleGeochemistry
DS1998-0090
1998
Gresham, D.A.Bauer, R.L., Gresham, D.A., Edson, J.D.Early Proterozoic ductile reworking of Archean basement in the Central Laramie Range: a complex response...Basement Tectonics, Vol. 12, pp. 219-222.WyomingCheyenne Belt, Trans Hudson Orogen, Central Plains
DS202008-1438
2019
Greshnyakov, E.D.Rezvukhina, O.V., Korsakov, A.V., Rezvukin, D.I., Zamyatin, D.A., Zelenovskiy, P.S., Greshnyakov, E.D., Shur, V.Y.A combined Raman spectroscopy, cathodoluminescence, and electron backscatter diffraction study of kyanite porphyroblasts from diamondiferous and diamond-free metamorphic rocks ( Kokchetav Massif).Journal of Raman Spectroscopy, 13p. PdfRussialuminescence

Abstract: A series of precise nondestructive analytical methods (Raman spectroscopy, cathodoluminescence, and EBSD—electron backscatter diffraction) has been employed to investigate the internal textures of kyanite porphyroblasts from diamondiferous and diamond?free ultrahigh?pressure metamorphic rocks (Kokchetav massif, Northern Kazakhstan). Such internal kyanite characteristics as twinning, radial fibrous pattern, and spotty zoning were identified by means of Raman and cathodoluminescence imaging, whereas an intergrowth of two kyanite crystals was distinguished only by Raman imaging. The EBSD analysis recorded an ~10-25° changing of orientations along the elongation in the investigated kyanite porphyroblasts. The absence of a radial fibrous pattern and a spotty zoning on the EBSD maps indicates that these textures are not related to variations in crystallographic orientation. The absence of clear zoning patterns (cores, mantles, and rims) on the Raman, cathodoluminescence, or EBSD maps of the kyanite porphyroblasts indicates the rapid single?stage formation of these porphyroblasts near the peak metamorphic conditions and the lack of recrystallization processes. The obtained results provide important implications for deciphering of mineral internal textures, showing that the data obtained by cathodoluminescence mapping can be clearly reproduced by Raman imaging, with the latter method occasionally being even more informative. This observation is of significant importance for the study of minerals that are unexposed on a thin section surface or Fe? and Ni?rich minerals that do not show luminescence emission. The combination of the Raman spectroscopic, cathodoluminescence, and EBSD techniques may provide better spatial resolution for distinguishing different domains and textural peculiarities of mineral than the selective application of individual approaches.
DS202101-0031
2020
Greshnyakov, E.D.Rezvukhina, O.V., Korsakov, A.V., Rezvukin, D.I., Mikhailenko, D.S., Zamyatin, D.A., Greshnyakov, E.D., Shur, V.Y.Zircon from diamondiferous kyanite gneisses of the Kokchetav massif: revealing growth stages using an integrated cathodluminescence- Raman spectroscopy- electron microprobe approach.Mineralogical Magazine, in press 28p. https://doi.org /10.1180/mgm.2020.95RussiaKokchetav
DS201705-0885
2017
Gress, M.van den Heuvel, Q., Matveev, S., Drury, M., Gress, M., Chinn, I., Davies, G.Genesis of diamond inclusions: an integrated cathodluminescence ( CL) and electron backscatter diffraction (EBSD) study on eclogitic and peridotitic inclusions and their diamond host.European Geosciences Union General Assembly 2017, Vienna April 23-28, 1p. 6564 AbstractAfrica, BotswanaDeposit - Jwaneng, Letlhakane
DS201708-1654
2017
Gress, M.Gress, M.Three phases of diamond growth spanning > 2.0 Ga beneath Letlhakane established by Re-Os and Sm-Nd systematics of individual eclogitic sulphide, garnet and clinopyroxene inclusions.11th. International Kimberlite Conference, OralAfrica, Botswanadeposit - Letlhakane

Abstract: The diamondiferous Letlhakane kimberlites are part of the Orapa kimberlite cluster (˜ 93.1 Ma) in north-eastern Botswana, located on the edge of the Zimbabwe Craton, close to the Proterozoic Magondi Mobile Belt. Here we report the first Re-Os ages of six individual eclogitic sulphide inclusions (3.0 to 35.7?g) from Letlhakane diamonds along with their rhenium, osmium, iridium and platinum concentrations, and carbon isotope, nitrogen content and N-aggregation data from the corresponding growth zones of the host diamonds. For the first time, Re-Os data will be compared to Sm-Nd ages of individual eclogitic silicate inclusions recovered from the same diamonds using a Triton Plus equipped with four 1013? amplifiers. The analysed inclusion set currently encompasses pairs of individual sulphides from two diamonds (LK040 sf4 & 5, LK113 sf1 & 2) and two sulphide inclusions from separate diamonds (LK048, LK362). Ongoing work will determine the Sm-Nd ages and element composition of multiple individual eclogitic garnets (LK113/LK362, n=4) and an eclogitic clinopyroxene (LK040) inclusion. TMA ages of the six sulphides range from 1.06 to 2.38 Ga (± 0.1 to 0.54 Ga) with Re and Os contents between 7 and 68 ppb and 0.03 and 0.3 ppb, respectively. The host diamond growth zones have low nitrogen abundances (21 to 43 ppm N) and high N-aggregation (53 to 90% IaB). Carbon isotope data suggests the involvement of crustal carbon (?13C between -19.3 to -22.7 ± 0.2 per mill) during diamond precipitation. Cathodoluminescence imaging of central plates from LK040 and LK113 displays homogenous internal structure with no distinct zonation. The two sulphide inclusions from LK040 define an 'isochron' of 0.92 ± 0.23 Ga (2SD) with initial 187Os/188Os = 1.31 ± 0.24. Sulphides from LK113 have clear imposed diamond morphology and indicate diamond formation at 0.93 ± 0.36 Ga (2SD) with initial 187Os/188Os = 0.69 ± 0.44. The variation in the initial 187Os/188Os does not justify including these inclusions (or any from other diamonds) on the same isochron and implies an extremely heterogeneous diamond crystallisation environment that incorporated recycled Os. C1-normalized osmium, iridium and platinum (PGE) compositions from the analysed sulphide inclusions display enrichment in Ir (3.4 to 33) and Pt (2.3 to 28.1) in comparison to eclogitic xenolith data from Orapa that are depleted relative to chondrite. The Re-Os isochrons determined in this study are within error of previously reported ages from the adjacent (˜40km) Orapa diamond mine (1.0 to 2.9 Ga) based on sulphide inclusions and a multi-point 990 ± 50 Ma (2SD) isochron for composite (n=730) silicate inclusions. Together with additional new Sm-Nd isochron age determinations from individual silicate inclusions from Letlhakane (2.3 ± 0.02 (n = 3); 1.0 ± 0.14 (n = 4) and 0.25 ± 0.04 Ga (n = 3), all 2SE) these data suggest a phase of Mesoproterozoic diamond formation as well as Neoarchean/Paleoproterozoic and Mesozoic diamond growth, in punctuated events spanning >2.0 Ga.
DS201708-1655
2017
Gress, M.Gress, M.Variation in diamond growth events recorded in Botswanan diamonds.11th. International Kimberlite Conference, PosterAfrica, Botswanadiamond morphology
DS201705-0833
2017
Gress, M.U.Gress, M.U., Pearson, D.G., Timmerman, S., Chinn, I.L., Koornneef, J., Davies, G.R.Diamond growth beneath Letlhakane established by Re-Os and Sm-Nd systematics of individual eclogitic sulphide, garnet and clinopyroxene inclusions.European Geosciences Union General Assembly 2017, Vienna April 23-28, 1p. 5540 AbstractAfrica, BotswanaDeposit - Letlhakane

Abstract: The diamondiferous Letlhakane kimberlites are part of the Orapa kimberlite cluster (˜ 93.1 Ma) in north-eastern Botswana, located on the edge of the Zimbabwe Craton, close to the Proterozoic Magondi Mobile Belt. Here we report the first Re-Os ages of six individual eclogitic sulphide inclusions (3.0 to 35.7?g) from Letlhakane diamonds along with their rhenium, osmium, iridium and platinum concentrations, and carbon isotope, nitrogen content and N-aggregation data from the corresponding growth zones of the host diamonds. For the first time, Re-Os data will be compared to Sm-Nd ages of individual eclogitic silicate inclusions recovered from the same diamonds using a Triton Plus equipped with four 1013? amplifiers. The analysed inclusion set currently encompasses pairs of individual sulphides from two diamonds (LK040 sf4 & 5, LK113 sf1 & 2) and two sulphide inclusions from separate diamonds (LK048, LK362). Ongoing work will determine the Sm-Nd ages and element composition of multiple individual eclogitic garnets (LK113/LK362, n=4) and an eclogitic clinopyroxene (LK040) inclusion. TMA ages of the six sulphides range from 1.06 to 2.38 Ga (± 0.1 to 0.54 Ga) with Re and Os contents between 7 and 68 ppb and 0.03 and 0.3 ppb, respectively. The host diamond growth zones have low nitrogen abundances (21 to 43 ppm N) and high N-aggregation (53 to 90% IaB). Carbon isotope data suggests the involvement of crustal carbon (?13C between -19.3 to -22.7 ± 0.2 per mill) during diamond precipitation. Cathodoluminescence imaging of central plates from LK040 and LK113 displays homogenous internal structure with no distinct zonation. The two sulphide inclusions from LK040 define an 'isochron' of 0.92 ± 0.23 Ga (2SD) with initial 187Os/188Os = 1.31 ± 0.24. Sulphides from LK113 have clear imposed diamond morphology and indicate diamond formation at 0.93 ± 0.36 Ga (2SD) with initial 187Os/188Os = 0.69 ± 0.44. The variation in the initial 187Os/188Os does not justify including these inclusions (or any from other diamonds) on the same isochron and implies an extremely heterogeneous diamond crystallisation environment that incorporated recycled Os. C1-normalized osmium, iridium and platinum (PGE) compositions from the analysed sulphide inclusions display enrichment in Ir (3.4 to 33) and Pt (2.3 to 28.1) in comparison to eclogitic xenolith data from Orapa that are depleted relative to chondrite. The Re-Os isochrons determined in this study are within error of previously reported ages from the adjacent (˜40km) Orapa diamond mine (1.0 to 2.9 Ga) based on sulphide inclusions and a multi-point 990 ± 50 Ma (2SD) isochron for composite (n=730) silicate inclusions. Together with additional new Sm-Nd isochron age determinations from individual silicate inclusions from Letlhakane (2.3 ± 0.02 (n = 3); 1.0 ± 0.14 (n = 4) and 0.25 ± 0.04 Ga (n = 3), all 2SE) these data suggest a phase of Mesoproterozoic diamond formation as well as Neoarchean/Paleoproterozoic and Mesozoic diamond growth, in punctuated events spanning >2.0 Ga.
DS201710-2235
2017
Gress, M.U.Koornneef, J.M., Gress, M.U., Chinn, I.L., Jelsma, H.A., Harris, J.W., Davies, G.R.Archaean and Proterozoic diamond growth from contrasting styles of large scale magmatism.Nature Communications, Vol. 8, 10.1038/s41467-017-00564-xAfrica, South Africadiamond inclusions

Abstract: Precise dating of diamond growth is required to understand the interior workings of the early Earth and the deep carbon cycle. Here we report Sm-Nd isotope data from 26 individual garnet inclusions from 26 harzburgitic diamonds from Venetia, South Africa. Garnet inclusions and host diamonds comprise two compositional suites formed under markedly different conditions and define two isochrons, one Archaean (2.95?Ga) and one Proterozoic (1.15?Ga). The Archaean diamond suite formed from relatively cool fluid-dominated metasomatism during rifting of the southern shelf of the Zimbabwe Craton. The 1.8 billion years younger Proterozoic diamond suite formed by melt-dominated metasomatism related to the 1.1?Ga Umkondo Large Igneous Province. The results demonstrate that resolving the time of diamond growth events requires dating of individual inclusions, and that there was a major change in the magmatic processes responsible for harzburgitic diamond formation beneath Venetia from the Archaean to the Proterozoic.
DS201806-1233
2018
Gress, M.U.Koornneef, J.M., Berndsen, M., Hageman, L., Gress, M.U., Timmerman, S., Nikogosian, I., van Bergen, M.J., Chinn, I.L., Harris, J.W., Davies, G.R.Melt and mineral inclusions as messengers of volatile recycling in space and time. ( olivine hosted inclusions)Geophysical Research Abstracts www.researchgate.net, Vol. 20, EGU2018-128291p. AbstractAfrica, South Africadiamond inclusions

Abstract: Changing recycling budgets of surface materials and volatiles by subduction of tectonic plates influence the compositions of Earth’s major reservoirs and affect climate throughout geological time. Fluids play a key role in processes governing subduction recycling, but quantifying the exact fate of volatiles introduced into the mantle at ancient and recent destructive plate boundaries remains difficult. Here, we report on the role of fluids and the fate of volatiles and other elements at two very different tectonic settings: 1) at subduction settings, and 2) within the subcontinental lithospheric mantle (SCLM). We will show how olivine-hosted melt inclusions from subduction zones and mineral inclusions in diamond from the SCLM are used to reveal how changing tectonic settings influence volatile cycles with time. Melt inclusions from the complex Italian post-collisional tectonic setting are used to identify changing subduction recycling through time. The use of CO2 in deeply trapped melt inclusions instead of in lavas or volcanic gases provides a direct estimate of deep recycling, minimizing possible effects of contamination during transfer through the crust. The aim is to distinguish if increased recycling of sediments from the down-going plate at continental subduction settings results in increased deep CO2 recycling or if the increased CO2 flux results from crustal degassing of the overriding plate. Both processes likely affected climate through Earth history but could thus far not be discriminated. The study of mineral inclusions and their host diamonds from the SCLM can link changes in the cycling of carbon-rich fluids and the time and process through which the carbon redistribution took place. We use Sm-Nd isotope techniques to date the mineral inclusions and use the carbon isotope data of the host diamonds to investigate the growth conditions. I will present case-studies of peridotitic and eclogitic diamonds from three mines in Southern Africa.
DS201807-1495
2018
Gress, M.U.Gress, M.U., Pearson, D.G., Chinn, I.L., Koornneef, J.M., Pals, A.S.M., Van der Valk, E.A.S., Davies, G.R.Episodic eclogitic diamond genesis at Jwaneng diamond mine, Botswana.Goldschmidt2018, abstract 1p.Africa, Botswanadeposit - Jwaneng

Abstract: The diamondiferous Jwaneng kimberlite cluster (~240 Ma) is located on the NW rim of the Archaean Kaapvaal Craton in central Botswana. Previous studies report eclogitic diamond formation in the late Archean (2.9 Ga) and in the Middle Proterozoic (1.5 Ga) involving different mantle and sedimentary components [1;2;3]. Here we report newly acquired Sm- Nd ages of individual eclogitic pyrope-almandine and omphacite inclusions along with their major element data and nitrogen data from the diamond hosts to re-examine Jwaneng’s diamond formation ages. The Sm-Nd isotope analyses were performed via TIMS using 1013? resistors [4]. An initial suite of three pyropealmandine and 14 omphacite inclusions yield 143Nd/144Nd from 0.51102±7 to 0.5155±5. 147Sm/144Nd vary from 0.024 to 0.469. Major element data defines two inclusion populations: (1) seven omphacites with high Mg#, high Cr# and one pyropealmandine with low-Ca define an isochron age of 1.93±0.16 Ga with ?Ndi= +3.5; (2) seven omphacites with low Mg#, low Cr# and two pyrope-almandines with low-Ca define an isochron age of 0.82±0.06 Ga with ?Ndi= +3.7. Nitrogen contents of corresponding diamond host growth zones in Group (1) are ? 50 at.ppm whereas Group (2) range between 50 to 700 at.ppm with N-aggregation > 70 %B. Additional data used to define “co-genetic” inclusion suites include Sr-isotopes and trace elements of the inclusions and carbon isotopes of the diamond hosts. Re-Os data of coexisting sulphide inclusions from the same silicate-bearing diamonds further validates the ages and indicates more periods of diamond formation at Jwaneng than previously assumed. The integrated data indicate the possibility of an extensive Paleoproterozoic diamond-forming event in southern Africa.
DS201809-2050
2018
Gress, M.U.Kohn, S.C., Speich, L., Bulanova, G.P., Smith, C.B., Gress, M.U., Davies, G.R.Modelling the temperature history of mantle lithosphere using FTIR maps of diamonds.Goldschmidt Conference, 1p. AbstractAfrica, Zimbabwe. Australia, Canada, Northwest Territories, South Africa, Botswanadeposit - Murowa, Argyle, Diavik, Venetia, Orapa

Abstract: FTIR maps of diamond plates, cut through the centre of growth, contain abundant information about changing defect concentrations from core to rim. These data can, in principle, be interpreted in terms of the variation in conditions of diamond growth and the temperatures experienced by the diamond during the period of mantle residence between growth and exhumation. Many diamonds show multiple growth zones that can be observed by cathodoluminescence. Importantly, the combination of nitrogen concentration and nitrogen aggregation measured by FTIR can be used to determine whether the growth zones are of similar or very different ages (Kohn et al., 2016). In this study, we use automated fitting of several thousand individual spectra within each FTIR map to define a model temperature for each pixel using the Python program, QUIDDIT. We then use a two-stage aggregation model to constrain potential temperature-time histories for each diamond. To take full advantage of the temperature history recorded by zoned diamonds, radiometric ages of inclusions are required. If the growth ages of each zone and the date of exhumation are well-known, then a model temperature can be calculated for each zone. The combination of zone-specific ages and improved quality and processing of FTIR spectra is able to provide unique new insights into the thermal history of diamondbearing lithospheric mantle. For the first time we will be able to use the N defects in diamonds to work out whether a particular location in the lithosphere has heated or cooled over long periods of geological time. The implications for the mechanism of formation of lithosphere will be discussed. We will illustrate the approach using examples of zoned diamonds from Murowa (Zimbabwe), Argyle (Australia), Diavik (Canada), Venetia (South Africa) and Orapa (Botswana).
DS201810-2308
2018
Gress, M.U.Davies, G.R., van den Heuvel, Q., Matveev, S., Drury, M.R., Chinn, I.L., Gress, M.U.A combined catholuminescence and electron backscatter diffraction examination of the growth relationships between Jwaneng diamonds and their eclogitic inclusions.Mineralogy and Petrology, doi.org/10.1007/s00710-018-0634-3 12p.Africa, Botswanadeposit - Jwaneng

Abstract: To fully understand the implications of the compositional information recorded by inclusions in diamond it is vital to know if their growth was syn- or protogenetic and the extent to which they have equilibrated with diamond forming agents. The current paradigm is that the majority of inclusions in diamond are syngenetic but recently this assumption has been questioned. This study presents an integrated cathodoluminescence (CL) and electron backscatter diffraction (EBSD) study of 8 diamonds containing eclogitic inclusions: 19 pyrope-almandine garnets, 12 omphacitic clinopyroxenes, 4 sulphides, 1 coesite and 1 rutile from the Jwaneng diamond mine, Botswana. Diamond plates were sequentially polished to expose inclusions at different levels and CL imaging and EBSD were performed to constrain the relationship between diamond and inclusion growth. Despite complex growth and resorption, individual diamonds are single crystals with a homogeneous crystallographic orientation. All individual inclusions have homogeneous crystallographic orientation and no resolvable compositional zonation. The combined CL and EBSD data suggest that epitaxial inclusion-diamond growth is rare (none of 24 inclusions) and that the imposition of cubo-octahedral faces on inclusions does not necessarily result in epitaxy. Individual diamonds contain inclusions that record evidence of both syngentic and protogenetic relationships with the host diamond and in one case an inclusion appears syngenetic to the diamond core but protogenetic to the growth zone that surrounds 70% of the inclusion. These findings emphasise that inclusions in diamonds have multiple modes of origin and that in order to validate the significance of geochronological studies, further work is needed to establish that there is rapid chemical equilibration of protogenetic inclusions with diamond forming agents at mantle temperatures.
DS201910-2261
2019
Gress, M.U.Gress, M.U., Smit, K.V., Chinn, I., Wang, W., Davies, G.R., Kornneef, J.M.Spectroscopic characteristics of Botswanan diamonds and their potential relationship with age.De Beers Diamond Conference, Not availableAfrica, Botswanadiamond growth zones
DS202011-2039
2020
Gress, M.U.Gress, M.U., Koorneef, J.M., Thomassot, E., Chinn, I.L., van Zuilen, K., Davies, G.R.Sm-Nd isochron ages coupled with C-N isotope data of eclogitic diamonds from Jwaneng, Botswana.Geochimica et Cosmochimica Acta, 10.1016/j.gca.2020.10.010 35p. PdfAfrica, Botswanadeposit - Jwaneng

Abstract: Constraining the formation age of individual diamonds from incorporated mineral inclusions and assessing the host diamonds’ geochemical characteristics allows determination of the complex history of diamond growth in the sub-continental lithospheric mantle (SCLM). It also provides the rare opportunity to study the evolution of the deep cycling of volatiles over time. To achieve these aims, Sm-Nd isotope systematics are presented for 36 eclogitic garnet and clinopyroxene inclusions from 16 diamonds from the Jwaneng mine, Botswana. The inclusions and host diamonds comprise at least two compositional suites that record different ‘mechanisms’ of diamond formation and define two isochrons, one Paleoproterozoic (1.8 Ga) and one Neoproterozoic (0.85 Ga). There are indications of at least three additional diamond-forming events whose ages currently cannot be well constrained. The Paleoproterozoic diamond suite formed by large-scale (> 100’s km), volatile-rich metasomatism related to formation and re-working of the Proto-Kalahari Craton. In contrast, the heterogeneous composition of the Neoproterozoic diamond suite indicates diamond formation on a small-scale, through local (< 10 km) equilibration of compositionally variable diamond-forming fluids in different eclogitic substrates during the progressive breakup of the Rodinia supercontinent. The results demonstrate that regional events appear to reflect the input of volatiles (i.e., carbon-bearing) derived from the asthenospheric mantle, whereas local diamond-forming events mainly promote the redistribution of volatiles within the SCLM. The occurrence of isotopically light carbon analysed in distinct growth zones from samples of this study (?13C < -21.1‰) provides further indication of a recycled origin for surface-derived carbon in some diamonds from Jwaneng. Determining Earth’s long-term deep carbon cycle using diamonds, however, requires an understanding of the nature and scale of specific diamond-forming events.
DS202103-0382
2021
Gress, M.U.Gress, M.U., Koornneef, J.M., Thomassot, E., Chinn, I.L., van Zuilen, K., Davies, G.R.Sm-Nd isochron age coupled with C-N isotope data of eclogitic diamonds from Jwaneng, Botswana.Geochimica et Cosmochimica Acta, Vol. 293, pp. 1-17. pdfAfrica, Botswanadeposit - Jwaneng

Abstract: Constraining the formation age of individual diamonds from incorporated mineral inclusions and assessing the host diamonds’ geochemical characteristics allows determination of the complex history of diamond growth in the sub-continental lithospheric mantle (SCLM). It also provides the rare opportunity to study the evolution of the deep cycling of volatiles over time. To achieve these aims, Sm-Nd isotope systematics are presented for 36 eclogitic garnet and clinopyroxene inclusions from 16 diamonds from the Jwaneng mine, Botswana. The inclusions and host diamonds comprise at least two compositional suites that record different ‘mechanisms’ of diamond formation and define two isochrons, one Paleoproterozoic (1.8?Ga) and one Neoproterozoic (0.85?Ga). There are indications of at least three additional diamond-forming events whose ages currently cannot be well constrained. The Paleoproterozoic diamond suite formed by large-scale (>100?s km), volatile-rich metasomatism related to formation and re-working of the Proto-Kalahari Craton. In contrast, the heterogeneous composition of the Neoproterozoic diamond suite indicates diamond formation on a small-scale, through local (<10?km) equilibration of compositionally variable diamond-forming fluids in different eclogitic substrates during the progressive breakup of the Rodinia supercontinent. The results demonstrate that regional events appear to reflect the input of volatiles (i.e., carbon-bearing) derived from the asthenospheric mantle, whereas local diamond-forming events mainly promote the redistribution of volatiles within the SCLM. The occurrence of isotopically light carbon analysed in distinct growth zones from samples of this study (?13C?
DS202103-0383
2021
Gress, M.U.Gress, M.U., Pearson, D.G., Chinn, I.L., Thomassot, E., Davies, G.R.Mesozoic to Paleoproterozoic diamond growth beneath Botswana recorded by Re-Os ages from individual eclogitic and websteritic inclusions.Lithos, 38p. PdfAfrica, Botswanadeposit - Orapa, Jwaneng

Abstract: Re-Os isotope systematics are reported from a suite of eclogitic and websteritic sulphide inclusions extracted from well-characterised diamond growth zones from the Orapa and Jwaneng kimberlite clusters. Re-Os ages (786 ± 250 Ma) are within uncertainty of previously determined Sm-Nd ages (853 ± 55 Ma), demonstrating isotopic equilibrium, at varying levels of completeness, across multiple isotopic systems in different minerals at the time of diamond formation and inclusion encapsulation. These data confirm the concept that inclusion isochron ages, when used with detailed textural/ growth zone control, reflect the timing of diamond crystallisation. Our data substantiate previous Re-Os and Sm-Nd inclusion ages of diamonds from Orapa and Jwaneng, indicating that major tectono-magmatic events formed discrete diamond populations of Paleo- (~ 2.0 to 1.7 Ga), Meso- (~ 1.2 to 1.1 Ga) and Neoproterozoic (~ 0.9 to 0.75 Ga) age. Some of these processes occurred simultaneously across the Kalahari Craton and can be traced over 100's of km illustrating the significance of diamond inclusions for monitoring continental tectonics. Inclusion ages indicating diamond formation that are younger than 300 Ma appear to be more common than previously recognised, consistent with evidence of relatively abundant, young, fluid-rich "fibrous" and polycrystalline diamonds at Jwaneng and Orapa. The increasingly widespread evidence for Mesozoic diamond-forming events in southern Africa and elsewhere appears closely linked with the kimberlite-related magmatism that affected these regions and subsequently transported diamonds to the surface. The inclusion isochron ages emphasise that diamond formation is a multi-stage and episodic process that can occur contemporaneously in disparate substrates and produce multiple diamond populations in the sub-continental lithospheric mantle.
DS202104-0581
2021
Gress, M.U.Gress, M.U., Pearson, D.G., Chinn, I.L., Thomassot, E., Davies, G.R.Mesozoic to Paleozoic diamond growth beneath Botswana recorded by Re-Os ages from individual eclogitic and websteritic inclusions.Appendix to previous Lithos article in March 2021, 11p. PdfAfrica, Botswanadeposit - Damtshaa, Orapa

Abstract: Re-Os isotope systematics are reported from a suite of eclogitic and websteritic sulphide inclusions extracted from well-characterised diamond growth zones from the Orapa and Jwaneng kimberlite clusters. Re-Os ages (786 ± 250 Ma) are within uncertainty of previously determined Sm-Nd ages (853 ± 55 Ma), demonstrating isotopic equilibrium, at varying levels of completeness, across multiple isotopic systems in different minerals at the time of diamond formation and inclusion encapsulation. These data confirm the concept that inclusion isochron ages, when used with detailed textural/ growth zone control, reflect the timing of diamond crystallisation. Our data substantiate previous Re-Os and Sm-Nd inclusion ages of diamonds from Orapa and Jwaneng, indicating that major tectono-magmatic events formed discrete diamond populations of Paleo- (~ 2.0 to 1.7 Ga), Meso- (~ 1.2 to 1.1 Ga) and Neoproterozoic (~ 0.9 to 0.75 Ga) age. Some of these processes occurred simultaneously across the Kalahari Craton and can be traced over 100's of km illustrating the significance of diamond inclusions for monitoring continental tectonics. Inclusion ages indicating diamond formation that are younger than 300 Ma appear to be more common than previously recognised, consistent with evidence of relatively abundant, young, fluid-rich “fibrous” and polycrystalline diamonds at Jwaneng and Orapa. The increasingly widespread evidence for Mesozoic diamond-forming events in southern Africa and elsewhere appears closely linked with the kimberlite-related magmatism that affected these regions and subsequently transported diamonds to the surface. The inclusion isochron ages emphasise that diamond formation is a multi-stage and episodic process that can occur contemporaneously in disparate substrates and produce multiple diamond populations in the sub-continental lithospheric mantle.
DS1994-1816
1994
Gresse, P.Unrug, R., Gresse, P., Wolmarana, L.Geodynamic map of Gondwana supercontinent assembly #1Geological Society of Australia Abstracts, No. 37, p. 440-1.GondwanaBrief overview
DS1993-0579
1993
Gresse, P.G.Gresse, P.G., Scheepers, R.Neoproterozoic to Cambrian (Namibian) rocks of South Africa: a geochronological and geotectonic reviewJournal of African Earth Sciences, Vol. 16, No. 4, pp. 375-393South AfricaGeochronology, Tectonics
DS1998-0532
1998
Gresse, P.G.Gresse, P.G., Thomas, R.J., De Beer, C.H., De Kock, G.S.The development of the Anti Atlas Orogen, Morocco: parallels with the Pan-African belts of southern AfricaJournal of African Earth Sciences, Vol. 27, 1A, p. 92. AbstractMoroccoOrogeny
DS2000-0361
2000
Gresse, P.G.Gresse, P.G., Silva, L.C., et al.The Neoproterozoic orogenic systems of western Gondwana in southern Africa and southern Brasil.Igc 30th. Brasil, Aug. abstract only 1p.Brazil, South AfricaGeodynamics - tectnics, Gondwanaland
DS2003-0501
2003
Gresse, P.G.Gresse, P.G.The preservation of alluvial diamond deposits in abandoned meanders of the middleJournal South African Institute of Mining and Metallurgy, Vol. 103, 9, pp. 535-38 Ingenta 1035419926South AfricaBlank
DS200412-0718
2003
Gresse, P.G.Gresse, P.G.The preservation of alluvial diamond deposits in abandoned meanders of the middle Orange River.Journal of the South African Institute of Mining and Metallurgy, Vol. 103, 9, pp. 535-38 Ingenta 1035419926Africa, South AfricaAlluvials
DS2002-1669
2002
Grevemeyer, I.Villinger, H., Grevemeyer, I., Kaul, N., Hauschild, J., Pfender, M.Hydrothermal heat flux through aged oceanic crust: where does the heat escape?Earth and Planetary Science Letters, Vol. 202, 1, pp.159-170.MantleGeothermometry
DS1996-0036
1996
Grew, E.S.Anovitz, L.M., Grew, E.S.Mineralogy, petrology and geochemistry of boron: an introductionReviews in Mineralogy, Vol. 33, pp. 1-40GlobalBoron, Mineralogy
DS201511-1842
2015
Grew, E.S.Hazen, R.M., Hystad, G., Downs, R.T., Golden, J.J., Pires, A.J., Grew, E.S.Earth's missing minerals.American Mineralogist, Vol. 100, pp. 2344-2347.TechnologyMineralogy

Abstract: Recent studies of mineral diversity and distribution lead to the prediction of >1563 mineral species on Earth today that have yet to be described-approximately one fourth of the 6394 estimated total mineralogical diversity. The distribution of these "missing" minerals is not uniform with respect to their essential chemical elements. Of 15 geochemically diverse elements (Al, B, C, Cr, Cu, Mg, Na, Ni, P, S, Si, Ta, Te, U, and V), we predict that approximately 25% of the minerals of Al, B, C, Cr, P, Si, and Ta remain to be described - a percentage similar to that predicted for all minerals. Almost 35% of the minerals of Na are predicted to be undiscovered, a situation resulting from more than 50% of Na minerals being white, poorly crystallized, and/or water soluble, and thus easily overlooked. In contrast, we predict that fewer than 20% of the minerals of Cu, Mg, Ni, S, Te, U, and V remain to be discovered. In addition to the economic value of most of these elements, their minerals tend to be brightly colored and/or well crystallized, and thus likely to draw attention and interest. These disparities in percentages of undiscovered minerals reflect not only natural processes, but also sociological factors in the search, discovery, and description of mineral species.
DS201905-1015
2019
Grew, E.S.Antonelli, M.A., DePaolo, D.J., Chacko, T., Grew, E.S., Rubatto, D.Radiogenic Ca isotope confirms post-formation K depletion of lower crust.Geochemical Perspective Letters, Vol. 10, pp. 43-48. doi:10.7185/ geochemlet.1904Mantlexenoliths

Abstract: Heat flow studies suggest that the lower crust has low concentrations of heat-producing elements. This could be due to either (i) greater fractions of basaltic rock at depth or (ii) metamorphic depletion of radioactive elements from rocks with more evolved (andesitic to granodioritic) compositions. However, seismic data suggest that lower crust is not predominantly basaltic, and previous studies (using Pb and Sr isotopes) have shown that lower crustal rocks have experienced significant losses of U and Rb. This loss, however, is poorly constrained for K, which is inferred to be the most important source of radioactive heat in the earliest crust. Our high precision Ca isotope measurements on a suite of granulite facies rocks and minerals from several localities show that significant losses of K (~60 % to >95 %) are associated with high temperature metamorphism. These results support models whereby reduction of heat production from the lower crust, and consequent stabilisation of continental cratons in the Precambrian, are largely due to high temperature metamorphic processes. Relative changes in whole rock K/Ca suggest that 20-30 % minimum (granitic) melt removal can explain the K depletions.
DS201809-2104
2018
Grewal, D.S.Tsuno, K., Grewal, D.S., Dasgupta, R.Core mantle fractionation of carbon in Earth and Mars: the effects of sulfur.Geochimica et Cosmochimica Acta, Vol. 238, pp. 477-495.Mantlecarbon

Abstract: Constraining carbon (C) fractionation between silicate magma ocean (MO) and core-forming alloy liquid during early differentiation is essential to understand the origin and early distribution of C between reservoirs such as the crust-atmosphere, mantle, and core of Earth and other terrestrial planets. Yet experimental data at high pressure (P)-temperature (T) on the effect of other light elements such as sulfur (S) in alloy liquid on alloy-silicate partitioning of C and C solubility in Fe-alloy compositions relevant for core formation is lacking. Here we have performed multi-anvil experiments at 6-13?GPa and 1800-2000?°C to examine the effects of S and Ni on the solubility limit of C in Fe-rich alloy liquid as well as partitioning behavior of C between alloy liquid and silicate melt (). The results show that C solubility in the alloy liquid as well as decreases with increasing in S content in the alloy liquid. Empirical regression on C solubility in alloy liquid using our new experimental data and previous experiments demonstrates that C solubility significantly increases with increasing temperature, whereas unlike in S-poor or S-free alloy compositions, there is no discernible effect of Ni on C solubility in S-rich alloy liquid. Our modelling results confirm previous findings that in order to satisfy the C budget of BSE, the bulk Earth C undergoing alloy-silicate fractionation needs to be as high as those of CI-type carbonaceous chondrite, i.e., not leaving any room for volatility-induced loss of carbon during accretion. For Mars, on the other hand, an average single-stage core formation at relatively oxidized conditions (1.0 log unit below IW buffer) with 10-16?wt% S in the core could yield a Martian mantle with a C budget similar to that of Earth’s BSE for a bulk C content of ?0.25-0.9?wt%. For the scenario where C was delivered to the proto-Earth by a S-rich differentiated impactor at a later stage, our model calculations predict that bulk C content in the impactor can be as low as ?0.5?wt% for an impactor mass that lies between 9 and 20% of present day Earth’s mass. This value is much higher than 0.05-0.1?wt% bulk C in the impactor predicted by Li et al. (Li Y., Dasgupta R., Tsuno K., Monteleone B., and Shimizu N. (2016) Carbon and sulfur budget of the silicate Earth explained by accretion of differentiated planetary embryos. Nat. Geosci.9, 781-785) because C-solubility limit of 0.3?wt% in a S-rich alloy predicted by their models is significantly lower than the experimentally derived C-solubility of ?1.6?wt% for the relevant S-content in the core of the impactor.
DS201902-0274
2019
Grewal, D.S.Grewal, D.S., Dasgupta, R., Sun, C., Tsuno, K., Costin, G.Delivery of carbon, nitrogen, and sulfur to the silicate Earth by a giant impact.Science Advances, Vol. 5, 1, Jan. 23, 10.1126/sciadv.aau3669 13p.Mantlecrater

Abstract: Earth’s status as the only life-sustaining planet is a result of the timing and delivery mechanism of carbon (C), nitrogen (N), sulfur (S), and hydrogen (H). On the basis of their isotopic signatures, terrestrial volatiles are thought to have derived from carbonaceous chondrites, while the isotopic compositions of nonvolatile major and trace elements suggest that enstatite chondrite-like materials are the primary building blocks of Earth. However, the C/N ratio of the bulk silicate Earth (BSE) is superchondritic, which rules out volatile delivery by a chondritic late veneer. In addition, if delivered during the main phase of Earth’s accretion, then, owing to the greater siderophile (metal loving) nature of C relative to N, core formation should have left behind a subchondritic C/N ratio in the BSE. Here, we present high pressure-temperature experiments to constrain the fate of mixed C-N-S volatiles during core-mantle segregation in the planetary embryo magma oceans and show that C becomes much less siderophile in N-bearing and S-rich alloys, while the siderophile character of N remains largely unaffected in the presence of S. Using the new data and inverse Monte Carlo simulations, we show that the impact of a Mars-sized planet, having minimal contributions from carbonaceous chondrite-like material and coinciding with the Moon-forming event, can be the source of major volatiles in the BSE.
DS201904-0741
2019
Grewal, D.S.Grewal, D.S., Dasgupta, R., Holmes, A.K., Costin, G., Li, Y., Tsuno, K.The fate of nitrogen during core-mantle seperation on Earth.Geochimica et Cosmochimica Acta, Vol. 251. pp. 87-115.Mantlenitrogen

Abstract: Nitrogen, the most dominant constituent of Earth’s atmosphere, is critical for the habitability and existence of life on our planet. However, its distribution between Earth’s major reservoirs, which must be largely influenced by the accretion and differentiation processes during its formative years, is poorly known. Sequestration into the metallic core, along with volatility related loss pre- and post-accretion, could be a critical process that can explain the depletion of nitrogen in the Bulk Silicate Earth (BSE) relative to the primitive chondrites. However, the relative effect of different thermodynamic parameters on the alloy-silicate partitioning behavior of nitrogen is not well understood. Here we present equilibrium partitioning data of N between alloy and silicate melt () from 67 new high pressure (P?=?1-6?GPa)-temperature (T?=?1500-2200?°C) experiments under graphite saturated conditions at a wide range of oxygen fugacity (logfO2????IW ?4.2 to ?0.8), mafic to ultramafic silicate melt compositions (NBO/T?=?0.4 to 2.2), and varying chemical composition of the alloy melts (S and Si contents of 0-32.1?wt.% and 0-3.1?wt.%, respectively). Under relatively oxidizing conditions (??IW ?2.2 to ?0.8) nitrogen acts as a siderophile element ( between 1.1 and 52), where decreases with decrease in fO2 and increase in T, and increases with increase in P and NBO/T. Under these conditions remains largely unaffected between S-free conditions and up to ?17?wt.% S content in the alloy melt, and then drops off at >?20?wt.% S content in the alloy melt. Under increasingly reduced conditions (
DS201905-1036
2019
Grewal, D.S.Grewal, D.S., Dasgupta, R., Holems, A.K., Costin, G., Li, Y., Tsuno, K.The fate of nitrogen during core-mantle separation on Earth.Geochimica et Cosmochimica Acta, Vol. 251, pp. 87-115.Mantlenitrogen

Abstract: Nitrogen, the most dominant constituent of Earth’s atmosphere, is critical for the habitability and existence of life on our planet. However, its distribution between Earth’s major reservoirs, which must be largely influenced by the accretion and differentiation processes during its formative years, is poorly known. Sequestration into the metallic core, along with volatility related loss pre- and post-accretion, could be a critical process that can explain the depletion of nitrogen in the Bulk Silicate Earth (BSE) relative to the primitive chondrites. However, the relative effect of different thermodynamic parameters on the alloy-silicate partitioning behavior of nitrogen is not well understood. Here we present equilibrium partitioning data of N between alloy and silicate melt () from 67 new high pressure (P?=?1-6?GPa)-temperature (T?=?1500-2200?°C) experiments under graphite saturated conditions at a wide range of oxygen fugacity (logfO2????IW ?4.2 to ?0.8), mafic to ultramafic silicate melt compositions (NBO/T?=?0.4 to 2.2), and varying chemical composition of the alloy melts (S and Si contents of 0-32.1?wt.% and 0-3.1?wt.%, respectively). Under relatively oxidizing conditions (??IW ?2.2 to ?0.8) nitrogen acts as a siderophile element ( between 1.1 and 52), where decreases with decrease in fO2 and increase in T, and increases with increase in P and NBO/T. Under these conditions remains largely unaffected between S-free conditions and up to ?17?wt.% S content in the alloy melt, and then drops off at >?20?wt.% S content in the alloy melt. Under increasingly reduced conditions (
DS1981-0317
1981
Grey, A.Nixon, P.H., Rogers, N.W., Gibson, I.L., Grey, A.Depleted and Fertile Mantle Xenoliths from Southern Africankimberlites.Annual Review of Earth and Planetary Science, Vol. 9, PP. 285-309.South AfricaKimberlite Genesis
DS200412-0719
2004
Grey, E.Grey, E., Clancy, J.The never ending story: human error and beyond.AUSIMM Bulletin, March-April, p. 60-62.AustraliaWork place environment
DS1975-0732
1978
Grey, G.P.Duncan, R.A., Hargraves, R.B., Grey, G.P.Age, Paleomagnetism and Chemistry of Melilite Basalts in The Southern Cape, South Africa.Geology Magazine (London), Vol. 115, No. 5, PP. 317-327.South AfricaGeochronology, Geochemistry
DS1987-0515
1987
Grey, I.E.Nickel, E.H., Grey, I.E., MadsenLucasite-(Ce),CeTi2(O, Oh06; a new mineral from WesternAustralia: its description and structureAmerican Mineralogist, Vol. 72, pp. 1006-1010Australia, LucasiteLamproite
DS1987-0516
1987
Grey, I.E.Nickel, E.H., Grey, I.E., Madsen, I.C.Lucasite (Ce) CeTi2 (O, OH)6 a new mineral from Western Australia: its description and structure.American Miner., Vol. 72, pp. 1006-10.AustraliaMineralogy, Lucasite, Deposit - Argyle mine
DS1998-0533
1998
Grey, I.E.Grey, I.E., Velde, D., Criddle, A.J.Haggertyite, a new magnetoplumbite type titanate mineral from the Prairie Creek (Arkansaw) lamproite.American Mineralogist, Vol. 83, pp. 1323-9.ArkansasLamproite - mineralogy, Deposit - Prairie Creek
DS202102-0225
2020
Greyling, D.R.Smart, K.A., Tappe, S., Woodland, A.B., Greyling, D.R., Harris, C., Gussone, N.Constraints on Archean crust recycling and the origin of mantle redox variability from delta 44/40 Ca - delta 18O - fO2 signatures of cratonic eclogites.Earth and Planetary Science Letters, doi.org/10.1016/ j.epsl.2020. 116720 19p. PdfAfrica, South Africadeposit - Bellsbank

Abstract: The nature of the deep calcium geochemical cycle through time is unresolved, in part due to the dearth of information about the calcium isotope composition of Archean recycled oceanic crust. Remnants of such ancient oceanic crust are preserved in the form of cratonic mantle eclogites, brought to surface as xenoliths in kimberlite magma eruptions. The ? 44 / 40Ca of fresh mantle-derived eclogite xenoliths (i.e., garnet and omphacite mineral separates) from the Bellsbank kimberlite on the Kaapvaal craton in South Africa are presented here in combination with their trace element compositions, garnet Fe3+ contents and ?18O values. The studied Bellsbank eclogite xenoliths have geochemical compositions that indicate oceanic crustal protoliths, with bulk Al2O3 from 15 to 27 wt.%, Eu anomalies from 0.8 to 2.6 and, significantly, garnet ?18O values from +2.7 to +6.2‰. Garnet Fe3+/?Fe contents yield logfO2(?FMQ) values between -4.0 and -1.2 for a depth range of 110-180 km, recording strong redox heterogeneity of the eclogite component within the Archean Kaapvaal mantle lithosphere. Reconstructed bulk eclogite MgO contents correlate negatively with fO2, suggesting that the redox compositions are related to magmatic differentiation during oceanic crust formation, excluding secondary metasomatic overprints. These data may thus emphasize that Archean basaltic oceanic crust had a similarly variable redox composition to modern MORB-type crust. Reconstructed bulk ? 44 / 40Ca values for the Bellsbank eclogites range from +0.28 to +1.56‰. Although some of the xenoliths have ? 44 / 40Ca values that overlap with the average mantle composition and modern MORB (+0.94 ± 0.1 and +0.83 ± 0.05‰), half of our dataset shows excursions to more extreme Ca isotopic compositions. Both higher and lower ? 44 / 40Ca relative to mantle compositions are recorded by the eclogites, with a general negative correlation with ?18O suggestive of seawater-alteration of oceanic crust. The combined low ? 44 / 40Ca (+0.28‰) and ?18O (+3.4‰) measured for one eclogite xenolith may record a subtle imprint by carbonate-rich mantle melts, which are known to contain isotopically light calcium contributed by recycled sediments. In contrast, the high ? 44 / 40Ca of up to +1.56‰ for some eclogite xenoliths, coupled with strong LREE depletion, can be explained by calcium isotope fractionation during partial melting. The protracted history of recycled oceanic crust as probed by cratonic mantle eclogites is recorded by their highly variable ? 44 / 40Ca-?18O-fO2 signatures. Whereas some of this heterogeneity can be linked to processes that operated on the Archean ocean floor such as seawater-alteration of basaltic crust, other sources of compositional variability are introduced by loss and addition of melts during subduction recycling and mantle residence. The observed ? 44 / 40Ca complexity of ancient recycled oceanic crust components at the scale of a single mantle-derived eclogite xenolith suite implies that mantle plume sourced intraplate magmas should reveal similarly strong calcium isotope variations contributed by apparently essential recycled crust components - as observed in the global oceanic island basalt record.
DS1996-0565
1996
Grezechnik, A.Grezechnik, A., Zimmermann, H.D., McMillan, P.F.FTIR micro-reflectance measurements of the CO2/3 ion content in basanite and leucitite glasses.Contributions to Mineralogy and Petrology, Vol. 125, No. 4, pp. 311-318.GlobalBasanite
DS200712-0849
2007
Grgeoire, M.Poitrasson, F., Delpech, G., Grgeoire, M., Moine, B.N.Significance of the mantle Fe isotope variations.Plates, Plumes, and Paradigms, 1p. abstract p. A799.Africa, South AfricaXenoliths
DS2001-1316
2001
Grhan, S.A.Zhou, D., Grhan, S.A., Chang, E.Z., Wang, B., Hacker, B.Paleozoic tectonic amalgamation of the Chinese Tian Shan: evidence from a transect along the Dushanzi-KugaGeological Society of America Memoir, No. 194, pp. 23-46.ChinaTectonics
DS201112-0727
2010
Grib, E.N.Naumov, V.B., Tolstykh, M.L., Grib, E.N., Leonov, V.L., Kononkova, N.N.Chemical composition, volatile components, and trace elements in melts of the Karymskii volcanic centre, Kamchatka and Golovnin a volcano, Kunashir Island....Vladykin, N.V., Deep Seated Magmatism: its sources and plumes, pp. 104-127.RussiaMineral inclusions
DS1994-1619
1994
Grib, V.Sinitsyn, A.V., Ermolaeva, L., Grib, V.The Arkangelsk diamond kimberlite province - a recent discovery in The north of the east European PlatformProceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 27-33.Russia, Commonwealth of Independent States (CIS)European platform, kimberlites, Deposit -Arkangelsk
DS1991-1595
1991
Grib, V.P.Sinitsyn, A.V., Ermolaeva, L.A., Grib, V.P.The Arkhangelsk diamond kimberlite province - a recent discovery in The north of the East-European PlatformProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 367-369RussiaNenoksa, Arkhangelsk, Mela River, Pomorskaya, Pionerskaya, Zolotitsa, Verkhotinskaya, Poltozero, Winter Coast
DS1992-1416
1992
Grib, V.P.Sinitsyn, A.V., Dauev, Yu.M., Grib, V.P.Structural setting and productivity of the kimberlites of the Arkhangelsk province #2Russian Geology and Geophysics, Vol. 33, No. 10, pp. 61-70.Russia, Commonwealth of Independent States (CIS), ArkangelskStructure, Kimberlites
DS1992-1417
1992
Grib, V.P.Sinitsyn, A.V., Dauev, Yu.M., Grib, V.P.Structural setting and productivity of the kimberlites of the ArkangelskProvince.Russian Geology and Geophysics, Vol. 33, No. 10, pp. 61-70.Russia, ArkangelskTectonics, Structure
DS1992-1449
1992
Grib, V.P.Sobolev, N.V., Pokhilenko, N.P., Grib, V.P., Skripnichenko, V.A.Specific composition and conditions of formation of deep seated mineralsRussian Geology and Geophysics, Vol. 33, No. 10, pp. 71-78.Russia, Commonwealth of Independent States (CIS), Arkangelsk, RussiaZolotisa Field, Tectonics, Explosion pipes, Kimberlites
DS201312-0334
2013
Griban, J.G.Griban, J.G., Samsonov, A.V., Salnikov, E.B., Lepehina, E.N.Kimberlitic zircons from the Paleoproterozoic Kimzero kimberlites ( Karelia): mineralogy, geochemistry and U-Pb geochronology.Goldschmidt 2013, AbstractRussia, KareliaDeposit - Kimozero
DS201312-0775
2013
Griban, J.G.Samsonov, A.V., Griban, J.G., Larionova, Y.O., Nosova, A.A., Tretyachenko, V.V.Evolution of deep crustal roots of the Arhangelsk Diamondiferous province: evidences from crustal xenoliths and xenocrysts from Devonian kimberlite pipes.Goldschmidt 2013, 1p. AbstractRussia, Kola PeninsulaDeposit - Arkangel
DS201507-0333
2015
Griban, Yu.G.Sazonova, L.V., Nosova, A.A., Kargin, A.V., Borisovskiy, S.E., Tretyachenko, V.V., Abazova, Z.M., Griban, Yu.G.Olivine from the Pionerskaya and V. Grib kimberlite pipes, Arkangelsk diamond province, Russia: types, composition, and origin.Petrology, Vol. 23, 3, pp. 227-258.RussiaDeposit - Grib
DS1860-0246
1875
Gribble, J.D.B.Gribble, J.D.B.A Manual of the District of Cuddapah in the Presidency of Madras.Cuddapah District Manual, IndiaRegional Geology
DS202101-0012
2020
Gribkoff, E.Gribkoff, E.Geologists shed light on the mantle with 3D model.EOS, 101, doi.org/10.1029/2020EOE152364 Dec. 4, 2p.Mantlegeophysics - seismics

Abstract: The model, which will incorporate 227 million surface wave measurements, could help with everything from earthquake characterization to neutrino geosciences.
DS201412-0443
2014
Griboedova, I.Kargin, A., Nosova, A., Larionova, Yu., Kononova, V., Borisovsky, S., Kovalchuk, E., Griboedova, I.Mesoproterozoic orangeites ( Kimberlites II) of west Karelia: mineralogy, geochemistry and Sr-Nd isotope composition.Petrology, Vol. 22, 2, pp. 151-183.RussiaOrangeites
DS1984-0315
1984
Grice, J.D.Grice, J.D., Robinson, G.W.Jeffreyite, (ca Na2) (be Al) Si2 (o Oh)7 a New Mineral Species and its Relation to the Melilite Group.Canadian Mineralogist., Vol. 22, PP. 443-446.Canada, QuebecJeffreyite, Melilite Group
DS1990-0602
1990
Grice, J.D.Grice, J.D., Boxer, G.L.Diamonds from Kimberley, Western AustraliaThe Mineralogical Record, Vol. 21, No. 6, November-December pp. 559-564AustraliaHistory, Diamonds morphology
DS200412-1535
2004
Grice, J.D.Petersen, O.V., Johnsen, O., Gault, R.A., Niedermayr, G., Grice, J.D.Taseqite, a new member of the eudialyte group from the Ilmassaq alkaline complex.Neues Jahrbuch fur Mineralogie - Monatshefte, No. 2, Feb. 1, pp. 83-96.Europe, GreenlandMineralogy
DS2001-1248
2001
GrienwaldWonik, T., Trippler, Geipel, Grienwald, PashkevitchMagnetic anomaly map for northern western and eastern EuropeTerra Nova, Vol. 13, pp. 203-13.EuropeGeophysics - magnetics
DS1992-0611
1992
Grier, R.Grier, R.Building sustainability into our economic decisionsCrs Perspectives, No. 41, November pp. 17-22CanadaEconomics, General
DS200912-0171
2009
Grierson, A.Di Francesco, D., Grierson, A., Kaputa, D., Meyer, T.Gravity gradiometer systems - advances and challenges.Geophysical Prospecting, Vol. 57, 4, pp. 615-623.TechnologyGradiometers - not specific to diamonds
DS1984-0316
1984
Gries, J.C.Gries, J.C.Tectonic History of Part of the Central Stable Region of The Midcontinent Area.Geological Society of America (GSA), Vol. 16, No. 2, FEBRUARY P. 85. (abstract.).KansasMid-continent
DS1989-1152
1989
Griesshaber, E.O'Nions, R.K., Griesshaber, E., Oxburgh, E.R.Rocks that are too hot to handleNature, Vol. 341, No. 6241, October 5, p. 391GlobalMantle, Magma
DS2003-0258
2003
Griesshaber, E.Clauser, C., Griesshaber, E., Neugebauer, H.J.Decoupled thermal and mantle helium anomalies: implications for the transport regime inJournal of Geophysical Research, Vol. 107, 11, Nov. 6, pp. DO1 10.1029/2001JB000675MantleTectonics, Geothermometry
DS200412-0334
2003
Griesshaber, E.Clauser, C.,Griesshaber, E., Neugebauer, H.J.Decoupled thermal and mantle helium anomalies: implications for the transport regime in continental rift zones.Journal of Geophysical Research, Vol. 107, 11, Nov. 6, pp. DO1 10.1029/2001 JB000675MantleTectonics, geothermometry
DS201903-0526
2019
Griev, R.Latypov, R., Chisryakova, S., Griev, R., Huhma, H.Evidence for igneous differentiation in Sudbury Igneous Complex and impact driven evolution of Terrestrial planet proto-crusts.Nature Communications, Vol. 10, # 508, pp. 1-13.Canada, Ontariometeorite

Abstract: Bolide impact is a ubiquitous geological process in the Solar System, which produced craters and basins filled with impact melt sheets on the terrestrial planets. However, it remains controversial whether these sheets were able to undergo large-scale igneous differentiation, or not. Here, we report on the discovery of large discrete bodies of melanorites that occur throughout almost the entire stratigraphy of the 1.85-billion-year-old Sudbury Igneous Complex (SIC) - the best exposed impact melt sheet on Earth - and use them to reaffirm that conspicuous norite-gabbro-granophyre stratigraphy of the SIC is produced by fractional crystallization of an originally homogeneous impact melt of granodioritic composition. This implies that more ancient and compositionally primitive Hadean impact melt sheets on the Earth and other terrestrial planets also underwent large-volume igneous differentiation. The near-surface differentiation of these giant impact melt sheets may therefore have contributed to the evolution and lithological diversity of the proto-crust on terrestrial planets.
DS1981-0194
1981
Grieve, D.A.Grieve, D.A.Diatreme Breccias in the Southern Rocky MountainsBritish Columbia Report of Fieldwork, FOR 1980, PP. 97-103.Canada, British Columbia, Crossing CreekPetrography
DS1985-0251
1985
Grieve, D.A.Grieve, D.A.1980- Petrology and Chemistry of the Cross KimberliteBritish Columbia Department of Mines Publishing, 1977-1981, PP. 34-41.Canada, British Columbia, PennsylvaniaStructure, Petrology, Analyses, Cehmistry, Petrogenesis
DS1995-0680
1995
Grieve, R.Grieve, R., Rupert, J., Smith, J., Thierriault, A.The record of terrestrial impact crateringGsa Today, Vol. 5, No. 10, Oct. pp. 189, 194-196.GlobalCraters -impact craters, Distribution, morphology
DS1987-0735
1987
Grieve, R.A.F.Thomas, M.D., Sharpton, V.L., Grieve, R.A.F.Gravity patterns and Precambrian structure in the North American centralplainsGeology, Vol. 15, No. 6, June pp. 489-492MidcontinentGeophysics, Tectonics
DS1988-0269
1988
Grieve, R.A.F.Grieve, R.A.F.Terrestrial impact craters; their recognition, nature and effectsRevista Geofiscica, Vol. 28, pp. 145-178GlobalImpact cratering, Review
DS1989-0546
1989
Grieve, R.A.F.Grieve, R.A.F.Hyper velocity impact cratering: a catastrophic terrestrial geologicprocessCatastrophes and evolution: Astronomical Foundations; S.V.M. Clube, Royal Astron. Society, 1989 pp. 57-79GlobalImpact cratering
DS1989-0547
1989
Grieve, R.A.F.Grieve, R.A.F., Adams, J., Goodacre, A.K., Nevitt, L., TeskeyThe Canadian geophysical atlasGeological Society of Canada (GSC) Forum 1989, P. 12 abstractOntarioGeophysical atlas
DS1989-1217
1989
Grieve, R.A.F.Pilkington, M., Grieve, R.A.F., Gibb, R.A., Halpenny, J.F.Derived potential field dat a sets for North AmericaGeological Society of Canada (GSC) Forum 1989, P. 20 abstractGlobalMidcontinent, Geophysics
DS1990-0181
1990
Grieve, R.A.F.Bechtel, T.D., Forsyth, D.W., Sharpton, V.L., Grieve, R.A.F.Variations in effective elastic thickness of the NorthAmericanlithosphereNature, Vol. 343, No. 6259, February 15, pp. 636-638MidcontinentGeophysics, Bouguer gravity
DS1990-0485
1990
Grieve, R.A.F.Forsyth, D.A., Pilkington, M., Grieve, R.A.F., Abbinett, D.Major circular structure beneath southern Lake Huron defined from potential field dataGeology, Vol. 18, No. 8, August pp. 773-777Ontario, Great LakesGeophysics -aeromagnetics, Tectonics
DS1990-0603
1990
Grieve, R.A.F.Grieve, R.A.F.Impact cratering on the earthScientific American, April pp. 66-73GlobalImpact cratering, Meteorites
DS1991-1448
1991
Grieve, R.A.F.Roest, W.R., Rupert, J.D., Grieve, R.A.F., Goodacre, A.K.Structural aspects of North America in the context of the World Bougueranomaly mapGeological Survey of Canada Forum held January 21-23, 1990 in Ottawa, p. 14 AbstractGlobalGeophysics -Gravity, Map
DS1991-1716
1991
Grieve, R.A.F.Thomas, M.D., Grieve, R.A.F., Sharpton, V.L.Structural fabric of the North American continent, as defined by gravity trends #1Proceedings of the Seventh International Conference on Basement, pp. 257-276.United States, CanadaRifting, Structure, tectonics, lineaments
DS1992-1200
1992
Grieve, R.A.F.Pilkington, M., Grieve, R.A.F.The geophysical signature of terrestrial impact cratersReviews of Geophysics, Vol. 30, No. 2, May pp. 161-181CanadaGeophysics -gravity, Impact craters
DS1993-0580
1993
Grieve, R.A.F.Grieve, R.A.F.Impact craters: lessons from and for the earthVistas in Astronomy, Vol. 36, pp. 203-230.GlobalAstronomy - solar system, Impact craters
DS1993-0581
1993
Grieve, R.A.F.Grieve, R.A.F.Impact craters: when will enough be enough?Nature, Vol. 363, No. 6431, June 24, pp. 670-671GlobalImpact craters
DS1993-0582
1993
Grieve, R.A.F.Grieve, R.A.F.Impact craters: lessons from and for the earthVistas in Astronomy, Vol. 36, pp. 203-230QuebecImpact craters
DS1994-0660
1994
Grieve, R.A.F.Grieve, R.A.F.Impact: a natural hazard in planetary evolutionEpisodes, Vol. 17, No. 1/2, pp. 9-17GlobalImpacts
DS1994-0661
1994
Grieve, R.A.F.Grieve, R.A.F., Masaitis, V.L.The economic potential of terrestrial impact cratersInternational Geology Review, Vol. 36, No. 2, February pp. 105-151.GlobalDistribution -impact craters, Review
DS1994-0662
1994
Grieve, R.A.F.Grieve, R.A.F., Masaitis, V.L.The economic potential of terrestrial impact cratersInternational Geology Review, Vol. 36, No. 2, February pp. 105-151GlobalImpact craters
DS1995-0443
1995
Grieve, R.A.F.Dressler, B.O., Grieve, R.A.F., Sharpton, V.L.Large meteorite impacts and planetary evolutionGeological Society of America (GSA) Special Paper, No. 293, 358p. $ 100.00GlobalBook -ad, Meteorites
DS1996-0566
1996
Grieve, R.A.F.Grieve, R.A.F., Masaitis, V.L.Impact diamondsGeological Survey of Canada, LeCheminant ed, OF 3228, pp. 183-186.CanadaImpact structure, Carbonados
DS200612-0498
2006
Grieve, R.A.F.Grieve, R.A.F., Cintala, M.J., Therriault, A.M.Large scale impacts and the evolution of the Earth's crust: the early years.Geological Society of America, Processes on the Earth, Special Paper 405, Chapter 2.MantleImpact processes
DS201312-0345
2013
Grieve, R.A.F.Gulick, S.P.S., Christeson, G.L., Barton, P.J., Grieve, R.A.F., Morgan, J.V., Urrutia-Fucugauchi, J.Geophysical characterization of the Chicxulub impact crater.Reviews of Geophysics, Vol. 51, 1, pp. 31-52.United States, MexicoMeteorite
DS1989-0559
1989
Grieveso..P.Gupta, S.K., Rajakuma.., V., Grieveso..P.The influence of weathering on the reduction of ilmenite with carbonMetall. T-B., Vol. 20, No. 5, October pp. 735-745. AX896GlobalIlmenite -general, Weathering
DS1992-0612
1992
Griffen, D.T.Griffen, D.T.Silicate crystal chemistryBlackwell Scientific, 416pGlobalChemistry -silicates, Book -ad
DS1985-0473
1985
Griffen, M.E.Mutschler, F.E., Griffen, M.E., Stevens, D.S., Shannon, S.S.JR.Precious metal deposits related to alkaline rocks in the North American Cordillera- an interpretative reviewTransactions Geological Society of South Africa, Vol. 88, pp. 355-377United StatesCordillera, Carbonatite
DS1975-1038
1979
Griffen, W.L.Griffen, W.L., Carswell, D.A., Nixon, P.H.Lower Crustal Granulites and Eclogites from LesothoProceedings of Second International Kimberlite Conference, Proceedings Vol. 2, PP. 59-86.LesothoPetrology
DS1986-0306
1986
Griffen, W.L.Griffen, W.L., O'Reilley, S.Y.Mantle drived sapphirineMineralogical Magazine, Vol. 50, December pp. 635-640AustraliaDelegate, Breccia
DS1986-0307
1986
Griffen, W.L.Griffen, W.L., Qvale, H.Superferrian eclogites and the crustal origin of garnet peridotites, Almklovdalen, NorwayThe Caledonide Orogen-Scandinavia and Related areas, Gee, D.G. and, pp. 803-812NorwayEclogites, Garnet Peridotites
DS1992-0613
1992
Griffen, W.L.Griffen, W.L., Ryan, C.G.Trace elements in garnets and chromites: their use in diamond exploration #3Preprint of paper to be presented Roundtable in India, November 25th., `6p. 1 table 15 figuresGlobalGeothermometry, Mineral chemistry -garnets, chromites
DS1995-1889
1995
Griffen, W.L.Taylor, W.R., Milledge, H.J., Griffen, W.L., Nixon, P.h.Characteristics of microdiamonds from ultramafic massifs in Tibet:authentic ophiolitic diamonds.....Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 623-624.China, TibetMicrodiamonds, Metamorphic
DS1998-0017
1998
GriffinAlard, O., Luguet, Lorand, Powell, O'Reilly, GriffinFurther insights on S content and behaviour in the lithospheric mantleMineralogical Magazine, Goldschmidt abstract, Vol. 62A, pp. 29-30.Australia, FranceSulphide mineralogy, Xenoliths
DS1998-0172
1998
GriffinBrown, R.W., Gallagher, Griffin, Ryan, De Wit, BeltonKimberlites, accelerated erosion and evolution of the lithospheric mantle beneath Kaapvaal - mid-Cretaceous..7th International Kimberlite Conference Abstract, pp. 105-107.South AfricaHeat flow data, uplift, Kaapvaal Craton
DS1998-1139
1998
GriffinPearson, N.J., Griffin, Kaminsky, Van AchterberghTrace element discrimination of garnet from Diamondiferous kimberlites andlamproites.7th. Kimberlite Conference abstract, pp. 673-5.South Africa, Russia, Siberia, Yakutia, Venezuela, GhanaGeochemistry, Garnets
DS1999-0545
1999
GriffinPearson, Griffin, Doyle, O'Reilly, Van Acterbergh, KiviXenoliths from kimberlite pipes of the Lac de Gras area, Slave Craton, Canada. (DO18, 27, A154S)7th International Kimberlite Conference Nixon, Vol. 2, pp. 644-58.Northwest TerritoriesPetrography, mineral chemistry, analyses, thermometry
DS2000-0374
2000
GriffinGwalani, L.G., Rock, N.M.S., Ramasamy, Griffin, MulaiComplexly zoned Ti rich melanite schorlomite garnets from Ambadungar carbonatite alkalic complex, DeccanJournal of Asian Earth Science, Vol. 18, No.2, Apr. pp.163-76.India, Gujarat, WesternCarbonatite, Deposit - Ambadungar
DS2000-0465
2000
GriffinKaminsky, F.V., Zakharchenko, Griffin, Channer BlinovaDiamond from the Guaniamo area, VenezuelaCanadian Mineralogist, Vol. 38, no, 6, Dec. pp. 1347-70.VenezuelaDiamond morphology, Mineral inclusions
DS2000-1040
2000
GriffinYatsenko, G.M., Panov, Belousoba, Lesnov, GriffinThe rare earth elements (REE) distribution in zircon from minettes of the Kirovograd Ukraine.Doklady Academy of Sciences, Vol. 370, No. 1, Jan-Feb pp.196-200.Russia, UkraineGeochronology, Minettes
DS2001-0062
2001
GriffinAulbach, S., Griffin, Pearson, O'Reilly, Doyle, KiviRe Os isotope evidence for Meso-Archean mantle beneath 2.7 Ga Contwoyto Terrane, implications tectonic historySlave-Kaapvaal Workshop, Sept. Ottawa, 5p. abstractMantleGeochemistry - major, trace elements, Slave Craton - tectonics
DS2001-0181
2001
GriffinChen, S., O'Reilly, S., Zhou, Griffin, Zhang, Sun, FengThermal and petrological structure of the lithosphere beneath Hannuoba, Sino Korean Craton, evidence xenolithLithos, Vol. 56, pp. 267-301.ChinaXenoliths, trace elements, structure
DS2001-0567
2001
GriffinKaminsky, F.V., Zakharchenko, O.D., Davies, R., GriffinSuperdeep diamonds from the Juin a area, Mato Grosso State, BrasilContributions to Mineralogy and Petrology, Vol. 140, pp. 734-53.GlobalDiamond - morphology, alluvial, ultra high pressure (UHP), Mineral chemistry
DS2001-0897
2001
GriffinPearson, N.J., Griffin, Spetsius, O'ReillyIn situ Re Os analysis of mantle sulphides: a new microanalytical technique to unravel the evolution...Slave-Kaapvaal Workshop, Sept. Ottawa, 6p. abstractRussia, Siberia, YakutiaGeochronology, Deposit - Udachnaya
DS2001-0999
2001
GriffinRyan, C.G., Can Achterberg, Griffin, Pearson, O'ReillyNuclear microprobe analysis of melt inclusions in minerals: windows on metasomatic processes in mantleNuclear Instruments and Methods, Phys. Res. B., Vo.l81, pp. 578-85.MantleMetasomatism
DS2001-1178
2001
GriffinVan Achterbergh, A.E., Griffin, Kivi, Pearson, O'ReillyCarbonatites at 200 km: quenched melt inclusions in megacrystalline lherzolite xenoliths Slave Craton.Journal of South African Earth Sciences, Vol. 32, No. 1, p. A 35.(abs)Northwest TerritoriesCarbonatite, A 154 kimberlite
DS2001-1246
2001
GriffinWin, T.T., Davies, R.M., Griffin, Wathanakul, FrenchDistribution and characteristics of diamonds from MyanmarJournal of Asian Earth Science, Vol. 19, No. 5, Aug. pp. 563-77.GlobalDiamond - morphology, Alluvials
DS2002-1236
2002
GriffinPearson, N.J., Alard, O., Griffin, Jackson, O'ReillyIn situ measurement of Re Os isotopes in mantle sulfides by laser ablation multicollector inductively..Geochimica et Cosmochimica Acta, Vol. 66, 6, pp. 1037-50.Russia, Siberia, Northwest TerritoriesCraton - mass spectrometry, rhenium, osmium, Peridotites
DS2002-1531
2002
GriffinSpetius, Z.V., Belousova, Griffin, O'Reilly, PearsonArchean sulphide inclusions in Paleozoic zircon megacrysts from the Mir kimberlite: implications datingEarth and Planetary Science Letters, Vol.199,1-2,pp.111-26., Vol.199,1-2,pp.111-26.Russia, YakutiaGeochronology - dating of diamonds, Deposit - Mir
DS2002-1532
2002
GriffinSpetius, Z.V., Belousova, Griffin, O'Reilly, PearsonArchean sulphide inclusions in Paleozoic zircon megacrysts from the Mir kimberlite: implications datingEarth and Planetary Science Letters, Vol.199,1-2,pp.111-26., Vol.199,1-2,pp.111-26.Russia, YakutiaGeochronology - dating of diamonds, Deposit - Mir
DS2002-1685
2002
GriffinWang, X., Griffin, O'Reilly, Zhou, Xu, Jackson, PearsonMorphology and geochemistry of zircons from late Mesozoic igneous complexes in coastal SE China:Mineralogical Magazine, Vol.66,2,pp. 235-52., Vol.66,2,pp. 235-52.China, southeastPetrogenesis
DS2002-1686
2002
GriffinWang, X., Griffin, O'Reilly, Zhou, Xu, Jackson, PearsonMorphology and geochemistry of zircons from late Mesozoic igneous complexes in coastal SE China:Mineralogical Magazine, Vol.66,2,pp. 235-52., Vol.66,2,pp. 235-52.China, southeastPetrogenesis
DS2003-1114
2003
GriffinPromprated, P., Taylor, L.A., Floss, C., Malkovets, V.G., Anand, M., GriffinDiamond inclusions from Snap Lake, NWT, Canada8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractNorthwest TerritoriesDiamonds - inclusions, Deposit - Snap Lake
DS200712-0773
2007
GriffinNasir, S., Al-Khirbashi, S., Al-Sayigh, Alharthy, Mubarek, Rollinson, Lazki, Belouova, Griffin, KaminskyThe first record of allochthonous kimberlite within the Batain Nappes, eastern Oman.Plates, Plumes, and Paradigms, 1p. abstract p. A706.Africa, OmanBatain melange
DS201012-0499
2010
GriffinMints, M.V., Belousova, E.A., Konilov, A.N., Natapov, Shchipansky, Griffin, O'Reilly, Dokukina, KaulinaMesoarchean subduction processes: 2.87 Ga eclogites from the Kola Peninsula, Russia.Geology, Vol. 38, 8, pp. 739-742.Russia, Kola PeninsulaBelomorian
DS201012-0500
2010
GriffinMints, M.V., Konilov, A.N., Dokukina, Kaulina, Belousova, Natapov, Griffin, O'ReillyThe Belomorian eclogite province: unique evidence of Meso-Neoarchean subduction and collisionsDoklady Earth Sciences, Vol. 434, 2, pp. 1311-1316.RussiaEclogite
DS201112-0639
2011
GriffinMalkovets, V.G., Griffin, Pearson, Rezvukhin, O'Reilly, Pokhilenko, Garanin, Spetsius, LitasovLate metasomatic addition of garnet to the SCLM: Os-isotope evidence.Goldschmidt Conference 2011, abstract p.1395.RussiaUdachnaya, Daldyn
DS201112-1156
2011
GriffinZedgenizov, D.A., Ragozin, Shatsky, Kagi, Odake, Griffin, Araujo, YuryevaEvidence for evolution of growth media in superdeep diamonds from Sao-Luis Brazil.Goldschmidt Conference 2011, abstract p.2244.South America, BrazilCl imaging
DS1998-1391
1998
Griffin, B.Spetsius, Z.V., Griffin, B.Secondary phases associated with diamonds in eclogites from Udachnaya pipe:implications for diamond genesis.7th International Kimberlite Conference Abstract, pp. 850-2.Russia, SiberiaXenoliths, Deposit - Udachnaya
DS1998-1393
1998
Griffin, B.Spetsius, Z.V., Taylor, W.R., Griffin, B.Major and trace element partioning between mineral phases in diamondiferous and non-Diamondiferous eclog..7th International Kimberlite Conference Abstract, pp. 856-8.Russia, SiberiaEclogites, Deposit - Udachnaya
DS2001-0061
2001
Griffin, B.Aulbach, S., Griffin, B., O'Reiley, S.How old is the Slave Craton mantle?Gemoc Annual Report 2000, pp. 22-23.MantleGeochronology, Slave Craton
DS2001-0228
2001
Griffin, B.Davies, R., Griffin, B.Superdeep diamonds from the Juin a area, Mato Grosso State, Brasil.Gemoc Annual Report 2000, p. 30.Northwest Territories, BrazilDiamond - morphology, Deposit - Lac de Gras, Mato Grosso areas
DS2001-0258
2001
Griffin, B.Djomani, Y.P., Griffin, B., O'Reilly, S., Pearson, N.The Slave Craton ( Canada) in deep analysisGemoc Annual Report 2000, p. 28-9.Northwest TerritoriesGeophysics - gravity, Lithosphere
DS2001-0412
2001
Griffin, B.Griffin, B., Pearson, N., O'Reilly, S.Sorting out the mantle: in situ measurement of Rhenium- Osmium (Re-Os) isotopes in mantle sulphides by LAM MC ICPNSGemoc Annual Report 2000, p. 32-3.FranceGeochronology - lherzolite
DS2001-0517
2001
Griffin, B.Jackson, S., Davies, R., Griffin, B.Diamond fingerprints - for science and peaceGemoc Annual Report 2000, p. 23.GlobalMicroprobe analysis, Conflict diamonds
DS2002-0678
2002
Griffin, B.Hauri, E., Bulanova, G., Pearson, G., Griffin, B.Carbon and nitrogen isotope systematics in a sector zoned diamond from the Mir kimberlite, Yakutia.Eos, American Geophysical Union, Spring Abstract Volume, Vol.83,19, 1p.Russia, YakutiaGeochronology - diamond morphology, Deposit - Mir
DS200512-0368
2005
Griffin, B.Griffin, B., Stern, R.Nano SIMS - yellow. Secondary ion mass spectrometry. Diamond source.Rough Diamond Review, No. 8, March pp. 42-44.Technology - SIMS
DS1990-0401
1990
Griffin, B.J.Dessai, A.G., Rock, N.M.S., Griffin, B.J., Gupta, D.Mineralogy and petrology of some xenolith bearing alkaline dykes associated with Deccan magmatism, south of Bombay IndiaEuropean Journal of Mineralogy, Vol. 2, No. 5, pp. 667-686IndiaAlkaline dykes, alkaline rocks, Xenoliths
DS1991-0424
1991
Griffin, B.J.Edwards, D., Rock, N.M.S., Taylor, W.R., Griffin, B.J., Sun, S-S.The Aries Diamondiferous kimberlite pipe, central Kimberley block, westernAustralia: mineralogy, petrology and geochem. of the pipe rock and indicatorsProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 82-84AustraliaMicaceous kimberlite, Group II, Geochemistry
DS1991-0606
1991
Griffin, B.J.Griffin, B.J., Muhling, J.R., Carroll, G.W., Rock, N.M.S.RECALC2- a package for processing mineral analyses produced by electronmicroprobeAmerican Mineralogist, Vol. 76, No. 1-1, Jan-February pp. 295-299GlobalComputer Program, RECALC2- Microprobe
DS1991-0972
1991
Griffin, B.J.Lee, D.C., Boyd, F.R., Griffin, B.J., Reddicliffe, T.Coanjula diamonds, northern Territory, AustraliaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 231-233AustraliaMicrodiamonds, Microscopy, diamond morphology
DS1991-1200
1991
Griffin, B.J.Muhling, J.R., Griffin, B.J.On recasting garnet analyses into end member molecules -revisitedComputers and Geosciences, Vol. 17, No. 1, January pp. 161-170GlobalComputer, Program -garnet analyses
DS1992-0412
1992
Griffin, B.J.Edwards, D., Rock, N.M.S., Taylor, W.R., Griffin, B.J.Mineralogy and petrology of the Aries Diamondiferous kimberlite pipe, central Kimberley block, western AustraliaJournal of Petrology, Vol. 33, No. 5, October pp. 1157-1191AustraliaKimberlite, Deposit -Aries
DS1992-0641
1992
Griffin, B.J.Gwalani, L.C., Rock, N.M.S., Griffin, B.J.Alkaline rocks and carbonatites of Amba Dongar and adjacent areas, DeccanProvince, Gujarat India: mineralogy, petrology and geochemistryProceedings of the 29th International Geological Congress. Held Japan August 1992, Vol. 2, abstract p. 578IndiaCarbonatite
DS1992-1285
1992
Griffin, B.J.Rock, N.M.S., Griffin, B.J., Edgar, A.D., Paul, D.K., Hergt, J.M.A spectrum of potentially Diamondiferous lamproites and minettes from the Jharia coalfield eastern IndiaJournal of Volcanology and Geothermal Research, Vol. 50, No. 1/2, April 15, pp. 55-84IndiaLamproites, Jharia coalfield
DS1994-1014
1994
Griffin, B.J.Lee, D.C., Boyd, S.R., Griffin, B.J., Griffin, B.W, Reddicliffe, T.Coanjuta diamonds, Northern Territory, AustraliaProceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 51-68.AustraliaDiamond morphology, Deposit -Coanjuta
DS1994-1437
1994
Griffin, B.J.Ramsay, R.R., Edwards, D., Taylor, W.R., Rock, N.M.S., Griffin, B.J.Compositions of garnet, spinel Aries Diamondiferous kimberlite pipe, Kimberley Block, implications for explJournal of Geochem. Exploration, Vol. 51, No. 1, Apr. pp. 59-78.AustraliaGeochemistry, Deposit -Aries
DS1994-1473
1994
Griffin, B.J.Rock, N.M.S., Gwalani, L.G., Griffin, B.J.Alkaline rocks and carbonatites of Amba Dongar and adjacent areas, Deccan alkaline Province, Gujarat India #2Mineralogy and Petrology, Vol. 51, No. 2-4, pp. 113-136.IndiaAlkaline rocks, Carbonatite
DS1995-0229
1995
Griffin, B.J.Bulanova, G.P., Griffin, B.J.The origin of complex agate textures in octahedral diamonds fromkimberlites.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 74-76.Russia, YakutiaDiamond morphology, Deposit -Mir, Aikal
DS1995-0681
1995
Griffin, B.J.Griffin, B.J., Bulanova, G.P., Taylor, W.R.Chlorine and FTIR mapping of nitrogen content and hydrogen distribution in a diamond from the Mir pipe -growth.Proceedings of the Sixth International Kimberlite Conference Extended, p. 191-93.GlobalDiamond morphology, Deposit -Mir
DS1995-0682
1995
Griffin, B.J.Griffin, B.J., Rissanen, J., Pooley, G.D., Lee, DearnA new Diamondiferous eclogite bearing kimberlitic occurrence from FinlandProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 198-200.FinlandEclogite
DS1995-0958
1995
Griffin, B.J.Kinny, P.D., Griffin, B.J., Brakhfogel, F.E.SHRIMP uranium-lead (U-Pb) (U-Pb) ages of perovskite and zircon from Yajutian kimberlitesProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 275-276.Russia, YakutiaGeochronology -SHRIMP, Deposit -Udachnaya, Polayrnaya, Dalnaya
DS1995-1331
1995
Griffin, B.J.Neeharika, Jha, Smith, S.B., Griffin, B.J., ChatterjeeDiamonds from the kimberlites of southeastern Raipur kimberlite field, Raipur district, Madhya Pradesh.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 266-268.India, Madhya PradeshDiamond morphology, Deposit -Payalikand, Bahradih
DS1995-1926
1995
Griffin, B.J.Trautman, R.L., Griffin, B.J., Taylor, W.R.A comparison of the microdiamonds from kimberlite and lamproite of Siberia and Australia.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 631-633.Australia, Russia, SiberiaMicrodiamonds, Diamond morphology
DS1996-0567
1996
Griffin, B.J.Griffin, B.J.Recent diamond research at University of Western Australia.FTIR, SHRIMPII, ESEM, FESEN, scanning electron microscope (SEM),CL, TEM.Australia Nat. University of Diamond Workshop July 29, 30., 1p.AustraliaBrief overview of activities
DS1997-1168
1997
Griffin, B.J.Trautman, R.L., Griffin, B.J., Taylor, W.R., Spetsius etA comparison of the microdiamonds from kimberlite and lamproite of Yakutia and Australia.Russian Geology and Geophysics, Vol. 38, No. 2, pp. 341-355.Australia, Russia, YakutiaMicrodiamonds, Morphology, physical properties
DS1998-0750
1998
Griffin, B.J.Kinny, P.D., Trautman, R.L., Griffin, B.J., Harte, B.Carbon isotopic analyses of microdiamonds7th International Kimberlite Conference Abstract, pp. 423-5.Australia, Russia, South AfricaMicrodiamonds, Analytical methodology, cathodluminesce, spectroscopy
DS1998-1481
1998
Griffin, B.J.Trautman, R.L., Griffin, B.J., Bulanova, G.P.Growth features and nitrogen aggregation properties of microdiamonds derived from kimberlitic diatremes.7th International Kimberlite Conference Abstract, pp. 926-8.Russia, Australia, Brazil, Finland, South AfricaCathodluminescence data, Micro diamonds
DS2002-0221
2002
Griffin, B.J.Bulanova, G.P., Pearson, D.G., Hauri, E.H., Griffin, B.J.Carbon and nitrogen isotope systematics within a sector growth diamond from the Mir kimberlite, Yakutia.Chemical Geology, Vol. 188, No. 1-2, pp. 105-123.Russia, YakutiaGeochronology, Deposit - Mir
DS2003-0182
2003
Griffin, B.J.Bulanova, G.P., Muchemwa, E., Pearson, D.G., Griffin, B.J., Kelly, S., KlemmeSyngenetic inclusions of yeminite in diamond from Sese kimberlite ( Zimbabwe) -8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractZimbabweDiamonds - inclusions, Deposit - Sese
DS2003-0785
2003
Griffin, B.J.Lee, D.C., Maddren, J., Griffin, B.J.The importance of chromite morphology in diamond exploration8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractAustraliaBlank
DS200412-0239
2004
Griffin, B.J.Bulanova, G.P., Muchemwa, E., Pearson, D.G., Griffin, B.J., Kelley, S.P., Klemme, S., Smith, C.B.Syngenetic inclusions of yimengite in diamond from Sese kimberlite - evidence for metasomatic conditions of growth.Lithos, Vol. 77, 1-4, Sept. pp. 181-192.Africa, ZimbabweMagnetoplumbite, grochronology argon, mantle, metasomat
DS200412-1102
2003
Griffin, B.J.Lee, D.C., Maddren, J., Griffin, B.J.The importance of chromite morphology in diamond exploration.8 IKC Program, Session 8, POSTER abstractAustraliaDiamond exploration
DS200712-0275
2007
Griffin, B.J.Downes, P.J., Griffin, B.J., Griffin, W.L.Mineral chemistry and zircon geochronology of xenocrysts and altered mantle and crustal xenoliths from the Aries micaceous kimberlite: constraints age..Lithos, Vol. 93, 1-2, pp. 175-198.AustraliaKimberly Craton - central composition age
DS200912-0702
2009
Griffin, B.J.Smith, C.B., Bulanova, G.P., Kohn, S.C., Milledge, H.J., Hall, A.E., Griffin, B.J., Pearson, D.G.Nature and genesis of Kalimantan diamonds.Lithos, In press available, 38p.Indonesia, KalimantanAlluvials, diamond morphology
DS201212-0096
2012
Griffin, B.J.Bulanova, G.P., Marks, A., Smith, C.B., Kohn, S.C., Walter, M.J., Gaillou, E., Shiry, S.B., Trautman, R., Griffin, B.J.Diamonds from Sese and Murowa kimberlites ( Zimbabwe) - evidence of extreme peridotitic lithosphere depletion and Ti-REE metasomatism.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, ZimbabweDeposit - Sese, Murowa
DS201412-0209
2014
Griffin, B.J.Downes, P.J., Demeny, A., Czuppon, G., Jacques, A.L., Verrall, M., Sweetapple, M., Adams, D., McNaughton, N.J., Gwalani, L.G., Griffin, B.J.Stable H-C-O isotope and trace element geochemistry of the Cummins Range carbonatite complex, Kimberley region Western Australia: implications for hydrothermal REE mineralization, carbonatite evolution and mantle source regions.Mineralium Deposita, in press available 28p.AustraliaCarbonatite
DS201412-0210
2014
Griffin, B.J.Downes, P.J., Demeny, A., Czuppon, G., Jaques, A.L., Verrall, M., Sweetapple, M., Adams, D., McNaughton, N.J., Gwalani, L.G., Griffin, B.J.Stable H-C-O isotope and trace element geochemistry of the Cummins Range carbonatite complex, Kimberley region western Australia: implications for hydrothermal REE mineralization, carbonatite evolution and mantle source regions.Mineralium Deposita, Vol. 49, p. 905-932.AustraliaCarbonatite
DS1994-1014
1994
Griffin, B.WLee, D.C., Boyd, S.R., Griffin, B.J., Griffin, B.W, Reddicliffe, T.Coanjuta diamonds, Northern Territory, AustraliaProceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 51-68.AustraliaDiamond morphology, Deposit -Coanjuta
DS1996-1384
1996
Griffin, D.Stull, A.T., Griffin, D.Life on the internet -geosciences - a student's guidePrentice Hall, 50p. $ 10.00 United StatesGlobalBook - table of contents, Websites
DS1984-0317
1984
Griffin, T.Griffin, T., Shaw, L.Petrology of the San Isabel Batholith, Southern Wet Mountains Colorado.Geological Society of America (GSA), Vol. 16, No. 4, P. 223 (abstract.).United States, Colorado, Rocky MountainsRelated Rocks
DS1985-0133
1985
Griffin, T.Cullers, R.L., Ramakrishnan, S., Berendsen, P., Griffin, T.Geochemistry and Petrogenesis of Lamproites, Late Cretaceous Age, Woodson County, Kansas, United States (us)Geochimica et Cosmochimica Acta ., Vol. 49, PP. 1383-1402.United States, Central States, KansasLamproite Terminology, Analyses, Silver City Dome
DS1990-1486
1990
Griffin, T.J.Tyler, I.M., Griffin, T.J.Structural development of the King Leopold Orogen, Kimberley region, Western AustraliaJournal of Structural Geology, Vol. 12, No. 5/6, pp. 703-714AustraliaStructure, Kimberley region
DS1999-0752
1999
Griffin, T.J.Tyler, I.M., Page, R.W., Griffin, T.J.Depositional age and provenance of the Marboo Formation from SHRIMPgeochronology: Paleoproterozoic evolutionPrecambrian Research, Vol. 95, No. 3-4, May 15, pp. 225-43.Australia, Western AustraliaGeochronology, Kimberley area - not specific to diamonds
DS2000-0362
2000
Griffin, T.J.Griffin, T.J., Page, R.W., Sheppard, TylerTectonic implications of Paleoproterozoic post collisional high Potassium felsic igneous rocks Kimberley....Precambrian Research, Vol. 100, No. 1-3, pp. 1-23.AustraliaTectonics
DS2003-1261
2003
Griffin, V.L.Shchukin, V.S., Sablukov, S.M., Sablukova, L.I., Belousova, E.A., Griffin, V.L.Late Vendian aerial alkaline volcanism in the Winter Coast kimberlite area, Arkangelsk8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractRussia, ArkangelskKimberlite geology and economics, Deposit - Winter Coast
DS2003-0869
2003
Griffin, W.Malkovets, V.G., Taylor, L.A., Griffin, W., O'Reilly, S., Pearson, N., PokhilenkoCratonic considitons beneath Arkhangelsk, Russia: garnet peridotites form the Grib8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractRussia, Kola PeninsulaMantle geochemistry, Deposit - Grib
DS200612-0499
2006
Griffin, W.Griffin, W., O'Reilly, S.TerraneChron - new tool for regional exploration.. based on zircon analyses.GEMOC Annual Report, 2005, p. 24.AustraliaTechnology - TerraneChron
DS201012-0470
2010
Griffin, W.Malkovets, V., Griffin, W., Poikhilenko, N., O'Reilly, S., Mishenin, S.Thickness of diamond bearing metasomatic aureoles in the cratonic SCLM.Goldschmidt 2010 abstracts, PosterMantleDiamond genesis
DS201212-0261
2012
Griffin, W.Griffin, W., Carbonell, R., Lenardic, A.The crust-mantle lithosphere system.34igc.org, Session abstractMantleGeodyanmics
DS201607-1381
2016
Griffin, W.Tappe, S., Griffin, W., Janney, P., Arndt, N., Gurney, J.The dynamic Earth and its kimberlite, cratonic mantle and diamond record through time.IGC 35th., Session A Dynamic Earth 1p. AbstractMantleKimberlite
DS201708-1656
2017
Griffin, W.Griffin, W.Super-reducing conditions in ancient and modern volcanic systems: implications for the carbon budget of the deep lithosphere.11th. International Kimberlite Conference, OralLithosphereCarbon
DS1960-0955
1968
Griffin, W.L.Griffin, W.L., Murthy, V.R.Abundance of Potassium, Rubidium, and Barium in Some Ultramafic Rocks and Minerals.Earth And Planetary Sciences Letters, Vol. 4, PP. 497-501.Norway, ScandinaviaPetrography
DS1970-0255
1971
Griffin, W.L.Bryhni, I., Griffin, W.L.Zoning in Eclogite Garnets from Nordfiord, West NorwayContributions to Mineralogy and Petrology, Vol. 32, PP. 112-125.Norway, ScandinaviaPetrography
DS1970-0299
1971
Griffin, W.L.Griffin, W.L., et al.Anomalously Elongated Rutile in Eclogite Facies Pyroxene And Garnet.Norske Geol. Tidsskr., Vol. 51, PP. 177-185.Norway, ScandinaviaPetrography
DS1970-0697
1973
Griffin, W.L.Griffin, W.L.Lherzolite Nodules from the Fen Alkaline Complex, NorwayContributions to Mineralogy and Petrology, Vol. 38, PP. 135-146.Norway, ScandinaviaUltramafic And Related Rocks
DS1975-0090
1975
Griffin, W.L.Griffin, W.L., Taylor, P.N.The Fen Damkjermite: Petrology of a Central Complex Kimberlite.Physics And Chemistry of The Earth, Vol. 9, PP. 163-178.Norway, ScandinaviaPetrology
DS1975-1008
1979
Griffin, W.L.Ehrenberg, S.N., Griffin, W.L.Garnet Granulite and Associated Xenoliths in Minette and Serpentinite Diatremes of the Colorado Plateau.Geology, Vol. 7, OCTOBER PP. 483-487.United States, Colorado PlateauBlank
DS1980-0087
1980
Griffin, W.L.Carswell, D.A., Griffin, W.L.Calculations of Equilibriation Conditions for Garnet Granulite and Garnet Websterite Nodules in African Kimberlite Pipes.Royal Society. EDINBURGH EARTH SCI. SECT. Transactions, South AfricaPetrology
DS1980-0149
1980
Griffin, W.L.Griffin, W.L.Nordic Carbonatite Symposium- Alno, Held 1979Lithos, Vol. 13, No. 2, PP. 109-110.Norway, ScandinaviaReview
DS1981-0113
1981
Griffin, W.L.Carswell, D.A., Griffin, W.L.Calculation of Equilibrium for Garnet Granulite and Garnet Websterite nodules in African Kimberlite Pipes.Tscherm. Mitt., Vol. 28, No. 3, PP. 229-234.South AfricaPetrology
DS1981-0114
1981
Griffin, W.L.Carswell, D.A., Griffin, W.L.Calculation of Equilibration Conditions for Garnet Granulite and Garnet WebsTschermaks Min. Petrol., Vol. 229-244.South Africa, LesothoChemical Analyses, Mineral Chemistry, Monastery, Liqhobong
DS1981-0195
1981
Griffin, W.L.Griffin, W.L.Superferric Eclogites and the Crustal Origin of Garnet Peridotites, Almklovdalen ,norway.Terra Cognita., Vol. 1, No. 1, P. 48. (abstract.).Scandinavia, NorwayBlank
DS1982-0134
1982
Griffin, W.L.Carswell, D.A., Griffin, W.L., Kresten, P.Peridotite Nodules from the Nogpetseu and Lipelaneng Kimberlites, Lesotho: a Crustal Origin or Mantle Origin.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 235, (abstract.).LesothoKimberlite, Genesis
DS1983-0168
1983
Griffin, W.L.Carswell, D.A., Griffin, W.L., Kresten, P.Peridotite Nodules from the Ngopetsoeu and Lipelaneng Kimberlites, Lesotho: a Crustal or Mantle Origin- Appendix.Annales Scientifiques De L' Universite De Clermont-ferrand Ii, No. 74, PP. 167-178.LesothoAnalyses, Petrography
DS1984-0012
1984
Griffin, W.L.Andersen, T., O'reilly, S.Y., Griffin, W.L.The Trapped Fluid Phase in Upper Mantle Xenoliths from Victoria, Australia: Implications for Mantle MetasomatismContributions to Mineralogy and Petrology, Vol. 88, PP. 72-85.Australia, South AustraliaPetrography, Inclusions, Microthermometry, Metasomatism
DS1984-0181
1984
Griffin, W.L.Carswell, D.A., Griffin, W.L., Kresten, P.Peridotite Nocules from the Ngopetsoeu and Lipelangene Kimberlites, Lesotho a Crustal or Mantle Origin.Thrid Kimberlite Conference, Vol. 2, PP. 229-243.Lesotho, Butha Buthe, RomaPetrography, Mineral Chemistry, Whole Rock
DS1984-0318
1984
Griffin, W.L.Griffin, W.L., Wass, S.Y., Hollis, J.D.Ultramafic Xenoliths from Bulletinenmerri and Gnotuk Maars, Victoria, Australia: Petrology of a Sub-continental Crust-mantle Transition.Journal of PETROLOGY, Vol. 25, PT. 1, PP. 53-87.Australia, VictoriaBasanite, Wehrlites, Spinel Lherzolites
DS1984-0567
1984
Griffin, W.L.O'reilly, S.Y., Griffin, W.L.A Xenolith Derived Geotherm for Southeastern Australia, And its Geophysical Implications.Geological Society of Australia., No. 12, ABSTRACT VOLUME PP. 418-419.Australia, Southeast AustraliaGeothermometry
DS1985-0507
1985
Griffin, W.L.O'reilly, S.Y., Griffin, W.L.A Xenolith Derived Geotherm for Southeastern Australia and Its Geophysical Implications.Tectonophysics, Vol. 111, No. 1-2, JANUARY 10TH. PP. 41-63.Australia, South AustraliaGeophysics
DS1986-0127
1986
Griffin, W.L.Carswell, D.A., Krogh, E.J., Griffin, W.L.Norwegian orthopyroxene eclogites: calculated equilibration conditions and petrogenetic implicationsThe Caledonide Orogen-Scandinavia and Related areas, Gee, D.G. Sturt, B.A., pp. 823-842NorwayEclogites
DS1986-0308
1986
Griffin, W.L.Griffin, W.L., Carswell, D.A.In situ metamorphism of norwegian eclogites: an exampleThe Caledonide Orogen-Scandinavia and Related areas, Gee, D.G.; Stury, B.A., pp. 813-822NorwayEclogites
DS1986-0309
1986
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y.Chemical and isotopic characteristics of multiply metasomatised mantle xenoliths from western VictoriaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 247-249AustraliaBlank
DS1986-0408
1986
Griffin, W.L.Johnson, B.D., Mayhewm M.A., O'Reilly, S.Y., Griffin, W.L., ArnottMagsat anomalies, crustal magnetisation, heat flow and kimberlite occurrences in AustraliaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, Geological, No. 16, pp. 127-129AustraliaGeophysics, Magnetics
DS1986-0623
1986
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L., Johnson, B.D.Petrological constraints on geophysical models for the lowercrust, mohoand mantle: thermal and seismic interpretationsProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 303-305AustraliaGeophysics
DS1987-0009
1987
Griffin, W.L.Andersen, Y., Griffin, W.L., O'Reilly, S.Y.Primary sulphide melt inclusions in mantle derived megacrystsandpyroxenitesLithos, Vol. 20, No. 4, July pp. 279-294Australia, NorwayBlank
DS1987-0255
1987
Griffin, W.L.Griffin, W.L., Kresten, P.Scandinavia-the carbonatite connectionin: Nixon, P.H. ed. Mantle xenoliths, J. Wiley, pp. 101-106ScandinaviaCarbonatite, p. 102 analyses Scandina
DS1987-0256
1987
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y.Evolution of Phanerozoic lithosphere: isotopic evidence for tectonic and igneous underplatingTerra Cognita, Conference abstracts Oceanic and Continental Lithosphere:, Vol. 7, No. 4, Autumn, abstract only p. 614AustraliaBlank
DS1987-0257
1987
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y.The composition of the lower crust and the nature of the continental MOHO-xenolith evidencein: Nixon, P.H. ed. Mantle xenoliths, J. Wiley, pp. 413-430GlobalBlank
DS1987-0258
1987
Griffin, W.L.Griffin, W.L., Sutherland, F.L., Hollis, J.D.Correlation of xenolith petrology and seismic data; an example from east central QueenslandUnited States Geological Survey (USGS) Circ.No. 956 Geophysics and petrology of the deep crust and upper, pp. 30-31AustraliaXenoliths
DS1987-0553
1987
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Eastern Australia-4000 kilometers of mantle samplesin: Nixon, P.H. ed. Mantle xenoliths, J. Wiley, pp. 267-280Australiap. 270 analyses mantle xenoliths
DS1987-0554
1987
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Thermal, seismic and petrologic characteristics of the lower crust And upper mantle; a case history based on xenoliths from eastern AustraliaUnited States Geological Survey (USGS) Circ.No. 956 Geophysics and petrology of the deep crust and upper, pp. 27-29AustraliaXenoliths
DS1988-0270
1988
Griffin, W.L.Griffin, W.L., Jaques, A.L., Sie, S.H., Ryan, C.G., Cousens, D.R.Conditions of diamond growth: a proton microprobe study of inclusions inWest Australian diamondsContributions to Mineralogy and Petrology, Vol. 99, No. 2, pp. 143-158AustraliaDiamond morphology
DS1988-0271
1988
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Stabel, A.Mantle metasomatism beneath western Victoria, Australia: III sotopicgeochemistry of chromium diopside lherzolites and aluminium augite pyroxenitesGeochimica et Cosmochimica Acta, Vol. 52, No. 2, February pp. 449-460AustraliaMetasomatism, Mantle
DS1988-0524
1988
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Mantle metasomatism beneath western Victoria: I. Metasomatic processes in chromium diopside lherzolitesGeochimica et Cosmochimica Acta, Vol. 52, No. 2, February pp. 433-448AustraliaMetasomatism, Mantle
DS1988-0525
1988
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L., Stabel, A.Evolution of Phanerozoic Eastern Australian Lithosphere: isotopic evidence for magmatic and tectonicunderplatingJournal of Petrology, Special Volume 1988- Oceanic and Continental, pp. 89-108AustraliaTectonics
DS1989-0548
1989
Griffin, W.L.Griffin, W.L., Cousens, D.R., Ryan, C.G., Sie, S.H., Suter, G.F.Application of the proton microprobe to diamond exploration and genesisMinpet 89 Mineralogy And Petrology Symposium Held Sydney, February, p. 13-14. AbstractAustraliaDiamond morphology, Microprobe
DS1989-0549
1989
Griffin, W.L.Griffin, W.L., Cousens, D.R., Ryan, C.G., Slen, S.H., Suter, G.F.nickel in chrome pyrope garnets: a new geothermometerContributions to Mineralogy and Petrology, Vol. 103, No. 2, pp. 199-202AustraliaGarnet -Mineralogy, Geothermometry
DS1989-0550
1989
Griffin, W.L.Griffin, W.L., Gurney, J.J., Ryan, C.G., Cousens, D.R., Sie, S.H.Trapping temperatures and trace elements in P type garnets indiamonds:a proton microprobe studyDiamond Workshop, International Geological Congress, July 15-16th. editors, pp. 23-25. AbstractSouth AfricaGeochemistry Analyses, Diamond morphology
DS1989-0551
1989
Griffin, W.L.Griffin, W.L., Smith, D., Boyd, F.R., Cousens, D.R., Ryan, C.G.Trace-element zoning in garnets from sheared mantlexenoliths.(Letter)Geochimica et Cosmochimica Acta, Vol. 53, No. 2, Feb. pp. 561-567AustraliaMantle-garnets, Mantle
DS1989-1051
1989
Griffin, W.L.Moore, R.O., Gurney, J.J., Griffin, W.L.Trace element abundance patterns in diamond inclusions from the MonasteryMine, South AfricaDiamond Workshop, International Geological Congress, July 15-16th. editors, pp. 65-68. AbstractSouth AfricaDiamond Inclusions -Monastery, Diamond morphology
DS1989-1390
1989
Griffin, W.L.Sie, S.H., Ryan, C.G., Cousens, D.R., Griffin, W.L.Application of the proton microprobe in mineral exploration andprocessingNucl. Instrum. Methods Phys. Res. Section, B., Vol. B40-B41, No. 1, 1988, pp. 690-697GlobalMicroprobe, Mineral analyses-kimberli
DS1989-1411
1989
Griffin, W.L.Smith, D., Griffin, W.L.Trace elements in garnets, mantle dynamics and meltsGeological Society of America (GSA) Annual Meeting Abstracts, Vol. 21, No. 6, p. A105. AbstractColorado PlateauMinette -The Thumb, Petrology
DS1990-0321
1990
Griffin, W.L.Chen, Y.D., O'Reilly, S.Y., Griffin, W.L.Application of the olivine-orthopyroxene-spinel-oxygen geobarometer to the redox state of the upper mantleTerra, Abstracts of International Workshop Orogenic Lherzolites and Mantle Processes, Vol. 2, December abstracts p. 129AustraliaGeochemistry, Geobarometry
DS1990-0604
1990
Griffin, W.L.Griffin, W.L., Smith, D., O'Reilly, S.Y., Ryan, C.G.Time scales of heating, metasomatism and deformation in the upper mantleGeological Society of Australia Abstracts, No. 25, No. A12.11 pp. 240. AbstractAustralia, South Africa, Colorado PlateauPeridotite xenoliths, Petrology
DS1990-1140
1990
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Trace element residence sites in metasomatised mantle:implications for basalt contaminationGeological Society of Australia Abstracts, No. 25, No. A12.11 pp. 237-238. AbstractAustraliaXenolith, Mantle
DS1990-1166
1990
Griffin, W.L.Pearson, N.J., O'Reilly, S.Y., Griffin, W.L.The lower crust beneath the eastern margin of the Australian craton:xenolith evidence for the gabbroto eclogite transitionGeological Society of Australia Abstracts, No. 25, No. A12.11 pp. 237. AbstractAustraliaXenolith, Eclogites
DS1991-0264
1991
Griffin, W.L.Chen, Y.D., Pearson, N.j., O'Reilly, S.Y., Griffin, W.L.Applications of olivine: orthopyroxene-spinel oxygen geobarometers to the redox state of the upper mantleProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 42-44Australia, China, South Africa, TanzaniaGeobarometry, Mantle
DS1991-0325
1991
Griffin, W.L.Cull, J.P., O'Reilly, S.Y., Griffin, W.L.Xenolith geotherms and crustal models in eastern AustraliaTectonophysics, Vol. 192, No. 3-4, June 20, pp. 359-366AustraliaXenoliths, Geothermometry
DS1991-0607
1991
Griffin, W.L.Griffin, W.L., Gurney, J.J., Sobolev, N.V., Ryan, C.G.Comparative geochemical evolution of cratonic lithosphere: South Africa andSiberiaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 119-121South Africa, RussiaGeochemistry, Craton, mineralogy
DS1991-0608
1991
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Ryan, C.G., Waldman, M.A.Indicator minerals from Prairie Creek and Twin Knobs lamproites: relation to diamond gradeProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 139-141ArkansasMicroprobe, Analyses
DS1991-0609
1991
Griffin, W.L.Griffin, W.L., Ryan, C.G., Fisher, N.I., Friedman, J.H.Trace elements in garnets and chromites: their use in diamond exploration #1Csiro, Preprint, 17pGlobalNickel thermometer, garnets, chromites, Geothermometry
DS1991-0610
1991
Griffin, W.L.Griffin, W.L., Ryan, C.G., Gurney, J.J., Sobolev, N.V., Win, T.T.Chromite macrocrysts in kimberlites and lamproites: geochemistry and origin #1Proceedings of Fifth International Kimberlite Conference held Araxa June, pp. 142-144South Africa, RussiaGeochemistry -chrome-spinels, Mantle, exploration
DS1991-0611
1991
Griffin, W.L.Griffin, W.L., Ryan, C.G., O'Reilly, S.Y., Nixon, P.N., Win, T.T.Trace elements in garnets from Tanzanian kimberlites: relation to diamond content and tectonic settingProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 145-147Tanzania, South AFricaMicroprobe data -garnets, Comparison
DS1991-0612
1991
Griffin, W.L.Griffin, W.L., Ryan, C.G., Schulze, D.J.Ilmenite and silicate megacrysts from Hamilton Branch: trace element geochemistry and fractional crystallizationProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 148-150KentuckyGeochemistry, Fractionation
DS1991-0636
1991
Griffin, W.L.Gurney, J.J., Moore, R.O., Griffin, W.L., Sobolev, N.V.The use of macrocryst minerals to predict diamond potential in kimberlites based on Southern Africa and a comparison with SiberiaGeological Society The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) First Annual Field Conference symposium held, 2pg. abstractSouth Africa, RussiaDiamond potential, Garnet, nickel thermometry
DS1991-0798
1991
Griffin, W.L.Jianxiong Zhou, Griffin, W.L., Jaques, A.L., Ryan, C.G., Win, T.T.Geochemistry of indicator minerals from Chinese kimberlites andlamproitesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 475-477ChinaPyrope, chromite, ilmenite, LIMA, yimengite, Proton microprobe, EMP
DS1991-1185
1991
Griffin, W.L.Moore, R.O., Gurney, J.J, Griffin, W.L., Shimizu, N.Ultra high pressure garnet inclusions in Monastery diamonds -trace element abundance patterns and conditions of originEur. Journal of Mineralogy, Vol. 3, No. 2, pp. 213-230South AfricaGeochemistry, Monastery -inclusions -garnet
DS1991-1238
1991
Griffin, W.L.Nixon, P.H., Griffin, W.L., Davies, G.R., Condliffe, E.chromium-garnet -diamond relationships in Venezuelan kimberlitesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 310-312VenezuelaDiamond inclusion, geothermometry, Guaniamo
DS1991-1265
1991
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L., Chen, Y.D.Geochemical and geophysical mantle domainsProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 316-317AustraliaSpinel lherzolite stability field, Geophysics, metasomatic processes
DS1991-1266
1991
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L., Ryan, C.G.Residence of trace elements in metasomatized spinel lherzolite xenoliths- aproton-microprobe studyContributions to Mineralogy and Petrology, Vol. 109, No. 1, pp. 98-113MantleMicroprobe spectrometry, Spinel lherzolite xenoliths
DS1991-1313
1991
Griffin, W.L.Pearson, D.G., O'Reilly, S.Y., Griffin, W.L.The thermal evolution of cratonic lower crust/upper mantle: examples from eastern Australia and southern AfricaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 332-333Australia, Southern AfricaKaapvaal craton, Geothermobarometry
DS1991-1316
1991
Griffin, W.L.Pearson, N.J., O'Reilly, S.Y., Griffin, W.L.The granulite to eclogite transition beneath the eastern margin of the Australian cratonEuropean Journal of Mineralogy, Vol. 3, No. 2, pp. 293-322AustraliaEclogite, Craton
DS1991-1317
1991
Griffin, W.L.Pearson, N.J., O'Reilly, S.Y., Griffin, W.L.Heterogeneity in the thermal state of the lower crust and upper mantle beneath eastern AustraliaAustralian Society of Exploration Geophysicists and Geological Society of Australia, 8th. Exploration Conference in the Bulletin., Vol. 22, No. 2, June pp. 295-298AustraliaMantle, Geothermometry
DS1991-1612
1991
Griffin, W.L.Smith, D., Griffin, W.L., Ryan, C.G., Sie, S.H.Trace element zonation in garnets from the Thumb -heating and melt infiltration below the Colorado PlateauContributions to Mineralogy and Petrology, Vol. 107, No. 1, pp. 60-79Colorado PlateauGeochemistry, Garnets -Thumb
DS1991-1894
1991
Griffin, W.L.Wyatt, B.A., Shee, S.R., Griffin, W.L., Zweistra, P., Robison, H.R.The petrology of the Cleve kimberlite, Eyre Peninsula, South AustraliaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 463-465AustraliaPetrography, Mineral chemistry
DS1992-0246
1992
Griffin, W.L.Chen, Y.D., Pearson, N.J., O'Reilly, S.Y., Griffin, W.L.Application of the olivine-orthopyroxene spinel oxygen geobarometers to redox state of upper mantle11th. Australian Geol. Convention Held Ballarat University College, Jan., Abstract onlyAustraliaMantle, Geobarometry
DS1992-0614
1992
Griffin, W.L.Griffin, W.L.Comparative geochemical evolution of Australian, South African and Siberian cratonic lithospheres11th. Australian Geol. Convention Held Ballarat University College, Jan., AbstractAustralia, South Africa, RussiaMantle, Craton
DS1992-0615
1992
Griffin, W.L.Griffin, W.L., Gurney, J.J., Ryan, C.G.Variations in trapping temperatures and trace elements in peridotite-suite inclusions African diamonds- evidence 2 inclusion suites implications lithosphere stratigrContributions to Mineralogy and Petrology, Vol. 110, No. 1, March pp. 1-15South AfricaDiamond inclusions, Lithosphere stratigraphy
DS1992-0616
1992
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Ryan, C.G.Composition and thermal structure of the lithosphere beneath South Siberia and China: proton microprobe studiesInternational Symposium Cenozoic Volcanic Rocks Deep seated xenoliths China and its, Abstracts pp. 65-66South Africa, Russia, Chinanickel thermometry, Xenocrysts
DS1992-0617
1992
Griffin, W.L.Griffin, W.L., Ryan, C.G.Trace elements in garnets and chromites: their use in diamond exploration #2International Roundtable Conference on Diamond Exploration and Mining, pp. 24-57AustraliaMineral chemistry, Nickel thermometry, Garnets, chromites
DS1992-0618
1992
Griffin, W.L.Griffin, W.L., Ryan, C.G., Gurney, J.J., Sobolev, N.V.Comparative geochemical evolution of the Australian, southern Africa and Siberian cratonic lithosphere11th. Australian Geol. Convention Held Ballarat University College, Jan., AbstractAustralia, South Africa, RussiaCraton, Geochemistry
DS1992-0619
1992
Griffin, W.L.Griffin, W.L., Ryan, C.G., Gurney, J.J., Sobolev, N.V.Comparative geochemical evolution of the southern African, Siberian and Australian cratonic lithosphereProceedings of the 29th International Geological Congress. Held Japan August 1992, Vol. 1, abstract p. 175South Africa, Russia, AustraliaGeochronology, Craton
DS1992-0620
1992
Griffin, W.L.Griffin, W.L., Ryan, C.G., Moore, R.O., Gurney, J.J.Geochemistry of magnesian ilmenites from kimberlites and basaltsV.m. Goldschmidt Conference Program And Abstracts, Held May 8-10th. Reston, p. A 44. abstractSouth AfricaGeochemistry, Magnesian ilmenites
DS1992-1082
1992
Griffin, W.L.Moore, R.O., Griffin, W.L., Gurney, J.J., Ryan, C.G., Cousens, D.R.Trace element geochemistry of ilmenite megacrysts from the Monasterykimberlite, South Africa.Lithos, Vol. 29, No. 1-2, December pp. 1-18.South AfricaGeochemistry, Ilmenites
DS1992-1145
1992
Griffin, W.L.O'Reilly, S.V., Griffin, W.L., Chen, D., Chen, Y.Mapping of mantle domains by clinopyroxene geochemistryProceedings of the 29th International Geological Congress. Held Japan August 1992, Vol. 1, abstract p. 175MantleGeochemistry, microprobe, Clinopyroxene
DS1992-1146
1992
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Modal and geochemical characteristics of metasomatism in mantle xenoliths from eastern AustraliaInternational Symposium Cenozoic Volcanic Rocks Deep seated xenoliths China and its, Abstracts pp. 92-93AustraliaMantle, Xenoliths
DS1992-1147
1992
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Trace element geochemistry of mantle derived apatitesV.m. Goldschmidt Conference Program And Abstracts, Held May 8-10th. Reston, p. A 80. abstractAustralia, VictoriaGeochemistry, Apatites
DS1992-1148
1992
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Nature of the east Australian lithosphereIn: Intraplate volcanism in eastern Australia and New Zealand, ed. R.W. Johnson, pp. 290-297.Mantle, Australia, New South WalesBlank
DS1992-1149
1992
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L., Chen, Y.D.Mantle terranes: geochemical, geophysical and geochronologicaldistinctions11th. Australian Geol. Convention Held Ballarat University College, Jan., Listing of papers to be given attempting to get volMantleTerranes, Geochemistry, geochronology, geophysics
DS1993-0558
1993
Griffin, W.L.Gong, W., Griffin, W.L., O'Reilly, S.Y.Polyphase metamorphic evolution of the Xuanhuaduian eclogite blocks, Dabie Shan high pressure metamorphic belt, central ChinaGeological Society of America Annual Abstract Volume, Vol. 25, No. 6, p. A265 abstract onlyChinaEclogite, Dabie
DS1993-0583
1993
Griffin, W.L.Griffin, W.L.Trace elements in garnet and chromites: evaluation of diamond explorationtargetsProspectors and Developers Diamond Workshop, held March 27th, Toronto, 25pSouth Africa, AustraliaGeochemistry, nickel thermometry, Garnets, chromites
DS1993-0584
1993
Griffin, W.L.Griffin, W.L., Ryan, G.C.Trace elements and indicator minerals: recent advances in diamondexplorationInternational Congress on Applied Mineralogy, ICAM93, held Fremantle, pp. 280-284GlobalGeochemistry, Mineralogy
DS1993-0585
1993
Griffin, W.L.Griffin, W.L., Sobolev, N.V., Ryan, C.G., Pokhilenko, N.P., WinTrace elements in garnets and chromites: diamond formation in the SiberianlithosphereLithos, Vol. 29, pp. 235-256Russia, Commonwealth of Independent States (CIS), Siberia, YakutiaGeochemistry, Diamond genesis
DS1993-0711
1993
Griffin, W.L.Ilupin, I.P., Griffin, W.L., Kaminsky, F.V.1st dat a on Zn in garnets from Yakutian kimberlites.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR*(in Russian), Vol. 332, No. 1, Sept. pp. 70-74.Russia, YakutiaZinc in garnets, Kimberlites
DS1993-1208
1993
Griffin, W.L.Pearson, N.J., O'Reilly, S.Y., Griffin, W.L.Thermal states of diverse lithospheric sections: lower crustal xenoliths across carton boundaries from South Africa and Australia.The Xenolith window into the lower crust, abstract volume and workshop, p. 16.South Africa, AustraliaKaapvaal craton, Tasman Fold Belt
DS1993-1358
1993
Griffin, W.L.Ryan, C.G., Griffin, W.L.The nuclear microprobe as a tool in geology and mineral explorationNucl. Institute B., Vol. 77, No. 1-4, May pp. 381-398.GlobalSpectrometry
DS1994-0292
1994
Griffin, W.L.Chen, Y.D., O'Reilly, S.Y., Kinny, P.D., Griffin, W.L.Dating lower crust and upper mantle events: an ion microprobe study of xenoliths from kimberlitic pipes, South Australia.Lithos, Vol. 32, No. 1-2, March, pp. 77-94.AustraliaGeochronology, Calcutteroo pipes, Mantle events
DS1994-0293
1994
Griffin, W.L.Chen, Y.D., O'Reilly, S.Y., Kinny, P.D., Griffin, W.L.Dating lower crust and upper mantl events - an ion microprobe study of xenoliths from kimberlitic pipes.Lithos, Vol. 32, No. 1-2, March pp. 77-94.Australia, South AustraliaXenoliths, Geochronology
DS1994-0503
1994
Griffin, W.L.Ewart, A., Griffin, W.L.Application of proton microprobe dat a to trace element partitioning in volcanic rocksChemical Geology, Vol. 117, No. 1-4, Nov. 1, pp. 251-284AustraliaVolcanics, Petrology -Microprobe
DS1994-0663
1994
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Ryan, C.G., Waldman, M.A.Indicator minerals from Prairie Creek and Twin Knobs lamproites: relations to diamond grade.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 302-311.ArkansasGeochemistry, Deposit -Prairie Creek, Crater of Diamonds, Twin Knobs
DS1994-0664
1994
Griffin, W.L.Griffin, W.L., Ryan, C.G.Trace elements in indicator minerals: evaluation of diamond explorationtargets.10th. Prospecting In Areas Of Glaciated Terrain, pp. 19-22. AbstractAustraliaGeochemistry, Exploration targets
DS1994-0665
1994
Griffin, W.L.Griffin, W.L., Ryan, C.G.Trace elements in indicator minerals: area selection and target evaluationin diamond exploration #1Preprint from author Diamond Exploration, JGE., 27p. 16 figs.Southern Africa, Tanzania, Arkansas, Australia, Russia, ChinaNickel thermometry, Geochemistry -exploration
DS1994-0666
1994
Griffin, W.L.Griffin, W.L., Ryan, C.G., Gurney, J.J., Sobolev, N.V., Win, T.T.Chromite macrocrysts in kimberlites and lamproites: geochemistry andorigin. #2Proceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 366-377.AustraliaChromite, Geochemistry
DS1994-0667
1994
Griffin, W.L.Griffin, W.L., Tyan, C.G., O'Reilly, S.Y.Mantle mapping for area selection in diamond explorationNorthwest Territories 1994 Open House Abstracts, p. 36. abstractNorthwest TerritoriesNews item, Nickel thermometry
DS1994-0676
1994
Griffin, W.L.Guo, J., O'Reilly, S.Y., Griffin, W.L.Mid-crustal carbonatites: evidence from inclusions in corundum megacrystsGeological Association of Canada (GAC) Abstract Volume, Vol. 19, p.MantleCarbonatite
DS1994-1281
1994
Griffin, W.L.Nixon, P.H., Griffin, W.L., Davies, G.R., Condiffe, E.chromium garnet indicators in Venezuela kimberlites and their bearing on the evolution of the Guyana craton.Proceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 378-387.Venezuela, GuyanaMineral chemistry, Garnets
DS1994-1671
1994
Griffin, W.L.Spetsius, Z.V., Bulanova, G.P., Griffin, W.L.Eclogite containing diamond with a garnet inclusion from the Mir pipeDoklady Academy of Sciences Acad. Science USSR, Vol. 323, No. 2, June pp. 115-119.Russia, YakutiaEcologite, diamond inclusions, Deposit -Mir
DS1994-1858
1994
Griffin, W.L.Viljoen, K.S., Robinson, D.N., Swash, P.M., Griffin, W.L., OtterDiamond and graphite bearing peridotite xenoliths from the Roberts Victorkimberlite.Proceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 285-303.South AfricaXenoliths, Deposit -Roberts Victor
DS1994-1956
1994
Griffin, W.L.Wyatt, B.A., Shee, S.R., Griffin, W.L., Zweistra, P., Robison, H.R.The petrology of the Cleve kimberlite, Eyre Peninsula South AustraliaProceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 62-79.AustraliaKimberlite, Deposit -Cleve
DS1994-1991
1994
Griffin, W.L.Zhou Jainxiong, Griffin, W.L., Jaques, A.L., Ryan, C.G., Win, T.T.Geochemistry of diamond indicator minerals from ChinaProceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 285-301.ChinaGeochemistry, Indicator minerals
DS1995-0355
1995
Griffin, W.L.Coopersmith, H.G., Griffin, W.L., Ryan, Win, McCallumTrace elements in garnets and chromites from Colorado Wyoming kimberlites as a guide to exploration.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 118-120.Colorado, WyomingMantle sampling, metasomatism, emplacement, resortion, Deposit -Colorado Wyoming District
DS1995-0541
1995
Griffin, W.L.Finnie, K., Fisher, D., Griffin, W.L., Harris, J., SobolevNitrogen aggregation in metamorphic diamonds from KazakhstanGeochimica et Cosmochimica Acta, Vol. 58, No.23, pp. 5173-5177.Russia, KazakhstanMetamorphic rocks, microdiamonds, Kokchetav massif
DS1995-0588
1995
Griffin, W.L.Garrit, D., Griffin, W.L., O'Reilly, S.Y.Archean and Proterozoic mantle in west GreenlandProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 179-80.GreenlandMantle, Geobarometry
DS1995-0683
1995
Griffin, W.L.Griffin, W.L., Kaminsky, F., O'Reilly, S.Y., Ryan, SobolevMapping the Siberian lithosphere with garnets and spinelsProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 194-5.Russia, SiberiaGeothermometry, Deposit -Daldyn, Alakit, Malo Botuobiya
DS1995-0684
1995
Griffin, W.L.Griffin, W.L., Moore, R.O., Ryan, C.G., Gurney, J., Win, T.Geochemistry of magnesian ilmenite megacrysts from southern African kimberlites #1Proceedings of the Sixth International Kimberlite Conference Extended, p. 196-7.South AfricaGeochemistry -ilmenite, Deposit -Kimberley, Uintjiesberg
DS1995-0685
1995
Griffin, W.L.Griffin, W.L., Ryan, C.G.Trace elements in indicator minerals: area selection and target evaluationin diamond exploration #3Proceedings of the Sixth International Kimberlite Conference Extended, p. 201-201.GlobalGeothermometry -garnet, nickel
DS1995-0686
1995
Griffin, W.L.Griffin, W.L., Ryan, C.G.Trace elements in indicator minerals: area selection and target evaluationin diamond exploration #2Journal of Geochemical Exploration, Vol. 52, pp. 311-338.Global, AustraliaDiamond exploration, Area selection
DS1995-0687
1995
Griffin, W.L.Griffin, W.L., Ryan, C.G., Min T.T.Mapping the earth mantle in 4D using the proton microprobeNucl. Institute, Vol. 104, No. 1-4, Sept. pp. 456-463.MantleImaging -proton microprobe
DS1995-0688
1995
Griffin, W.L.Griffin, W.L., Ryan, C.G., O'Reilly, S.Y., Gurney, J.J.Lithosphere evolution beneath the Kaapvaal Craton: 200-80 MaProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 203-4.South AfricaGeothermometry, Craton -Kaapvaal
DS1995-0689
1995
Griffin, W.L.Griffin, W.L., Ryan, C.O., Win, T.T.Mapping the earth mantle in 4D using the proton microprobeNucl. Institute B., Vol. 104, No. 1-4, Sept. pp. 456-463MantleMicroprobe, Geochemistry
DS1995-0690
1995
Griffin, W.L.Griffin, W.L., Smith, D., O'Reilly, S.Y., Ryan, C.G.Time scales of heating and metasomatism in the upper mantleGeological Association of Canada (GAC)/Mineralogical Association of, Vol. 20, p. A39 AbstractMantleMetasomatism, Microprobe
DS1995-0842
1995
Griffin, W.L.Ilupin, I.P., Griffin, W.L., Kaminsky, F.V.Zinc in kimberlite garnets from YakutiaDoklady Academy of Sciences USSR, Vol. 333, No. 8, August, pp. 74-79.Russia, YakutiaMicroprobe - garnets, Zinc
DS1995-1192
1995
Griffin, W.L.McCammon, C.A., Griffin, W.L., Shee, S.H., O'Neill, H. St.Determination of ferric iron variation within zoned garnets from the Wesselton kimberlite using Mossbauer.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 362-364.South AfricaSpectroscopy, Deposit -Wesselton
DS1995-1397
1995
Griffin, W.L.O'Reilly, S., Griffin, W.L.4-D lithosphere mapping: constructing stratigraphic sections of lower crust and upper mantle in space and timeProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 407-409.MantlePaleogeothermometry, Geophysics -lithosphere
DS1995-1398
1995
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Trace element partioning garnet and clinopyroxene in mantle derived pyroxenites and eclogites:P-T-X controlsChemical Geology, Vol. 121, No. 1-4, April 5, pp. 105-130.MantlePyroxenites, pressure, temperature controls, Eclogites
DS1995-1465
1995
Griffin, W.L.Pearson, N.J., O'Reilly, S.Y., Griffin, W.L.The crust mantle boundary beneath cratons and craton margins: a transect across southwest margin KaapvaalLithos, Vol. 36, No. 3/4, Dec. 1, pp. 257-288.South AfricaCraton -Kaapvaal, Geothermometry
DS1995-1635
1995
Griffin, W.L.Ryan, C.G., Griffin, W.L., Pearson, N.J., Win, T.T.Garnet geotherms: derivation of P-T dat a from chromium-Pyrope garnetsProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 476-478.South Africa, Russia, Siberia, Mongolia, China, Solomon IslandsGeothermometry, Deposit -Kaapvaal area and Dadlyn area
DS1995-1639
1995
Griffin, W.L.Sablukov, L., Sablukov, S., Griffin, W.L., O'Reilly, S.Y.Lithosphere evolution in the Archangelsk kimberlite provinceProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 487-489.Russia, ArkangelskGeochemistry -major elements, Deposit -Zolotitsa field, Zimni Bereg
DS1995-1813
1995
Griffin, W.L.Spetsius, Z.V., Griffin, W.L.Trace elements in silicate and ore minerals of eclogite xenoliths From kimberlite pipe Udachnaya, Yakutia.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 575-577.Russia, YakutiaGeochemistry, xenoliths, Deposit -Udachnaya
DS1996-0191
1996
Griffin, W.L.Bulanova, G.P., Griffin, W.L., Barnes, S-J.Trace elements in sulfide inclusions from Yakutian diamondsContributions to Mineralogy and Petrology, Vol. 124, No. 2, pp. 111-125.Russia, YakutiaSulphide inclusions, Diamond morphology
DS1996-0488
1996
Griffin, W.L.Garrit, D., Griffin, W.L., O'Reilly, S.Y.Processes in Archean and Proterozooic mantle in West GreenlandV.m. Goldschmidt Conference, Held March 31, 1p. abstractGreenlandKimberlite dykes, Paleogeotherms
DS1996-0568
1996
Griffin, W.L.Griffin, W.L., Kaminsky, F.V., Ryan, C.G., O'Reilly, S.Y.Thermal state and composition of the lithospheric mantle beneath the Daldyn kimberlite field, Yakutia.Tectonophysics, Vol. 262, No. 1-4, Sept. 30, pp. 19-33.Russia, YakutiaGeophysics, Deposit -Daldyn area
DS1996-0569
1996
Griffin, W.L.Griffin, W.L., O'Reilly, S.R., Konov, A., Ryan, C.G.Secular evolution of sub-continental mantleInternational Geological Congress 30th Session Beijing, Abstracts, Vol. 1, p. 115.ChinaGarnets, Geothermometry
DS1996-0570
1996
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Ionov, D.A., Ryan, C.G.Secular evolution of sub continental mantleGeological Society of Australia 13th. Convention held Feb., No. 41, abstracts p.167.AustraliaMantle, Kimberlites
DS1996-0571
1996
Griffin, W.L.Griffin, W.L., Ryan, C.G.An experimental calibration of the nickel in garnet geothermometer withapplications. Discussion by Canil.Contributions to Mineralogy and Petrology, Vol. 124, No. 2, pp. 216-220.GlobalGeothermometry, Nickel - garnet
DS1996-0572
1996
Griffin, W.L.Griffin, W.L., Smith, D., Ryan, C.G., O'Reilly, S.Y., WinTrace element zoning in mantle minerals: metasomatism and thermal events In the upper mantle.Canadian Mineralogist, Vol. 34, pt. 6, pp. 1179-93.MantleMetasomatism, Peridotite
DS1996-0574
1996
Griffin, W.L.Guo, J., O'Reilly, S.Y., Griffin, W.L.Zircon inclusions in corundum megacrysts: 1. trace element geochemistry and clues to the origin ...Geochimica et Cosmochimica Acta, Vol. 60, No. 13, pp. 2347-63.Australia, ChinaGeochemistry - corundum megacrysts, Alkali basalts
DS1996-1057
1996
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.4-D lithosphere mapping -methodology and examplesTectonophysics, Vol. 262, No. 1-4, Sept. 30, pp. 3-18.Russia, YakutiaGeophysics, Methodology
DS1996-1089
1996
Griffin, W.L.Pearson, N.J., O.Reilly, S.Y., Griffin, W.L.Lower crust geothermsInternational Geological Congress 30th Session Beijing, Abstracts, Vol. 1, p. 119.South AfricaKaapvaal Craton, Geothermometry
DS1996-1233
1996
Griffin, W.L.Ryan, C.G., Griffin, W.L., Peirson, N.J.Garnet geotherms: pressure temperature dat a from chromium-pyrope garnet xenocrysts in volcanic rocks.Journal of Geophysical Research, Vol. 101, No. B3, March 10, pp. 5611-26.AustraliaGeothermometry, Volcanics -xenocrysts
DS1996-1234
1996
Griffin, W.L.Ryan, C.G., Griffin, W.L., Win, T.T.Diamond exploration and mantle structure imaging using pixiemicroanalysis.Nucl. Institute B., Vol. 109, April pp. 601-605.AustraliaMantle structure, Remote sensing
DS1996-1571
1996
Griffin, W.L.Xu, X., O'Reilly, S.Y., Griffin, W.L.Thermal and redox states of subcontinental lithospheric mantle: constraints from basalt-borne mantle xenolithsInternational Geological Congress 30th Session Beijing, Abstracts, Vol. 1, p. 118.ChinaXenoliths
DS1996-1572
1996
Griffin, W.L.Xu, X., O'Reilly, S.Y., Griffin, W.L.A xenolith derived geotherm and the crust mantle boundary at Qilin southeastern China.Lithos, Vol. 38, No. 1/2, pp. 41-62.ChinaXenoliths, Geothermometry
DS1996-1593
1996
Griffin, W.L.Zhang, A., Griffin, W.L., Win, T.T., Xu, D.Lithosphere mapping in eastern Chin a garnets and spinels from kimberlitic and lamproitic rocks.International Geological Congress 30th Session Beijing, Abstracts, Vol. 2, p. 398.ChinaGeothermometry, Kimberlites, lamproites
DS1997-0075
1997
Griffin, W.L.Barashkov, Yu.P., Griffin, W.L., Talnikova, S.B.Trace elements in sulfide inclusions in olivine from the Udachnaya kimberlite pipe, Yakutia.Geochemistry International, Vol. 35, No. 7, July, pp. 676-680.Russia, YakutiaInclusions - sulfide, olivine, Deposit - Udachnaya
DS1997-0444
1997
Griffin, W.L.Griffin, W.L., Fisher, N.J., Friedman, J.H., Ryan, C.G.Statistical techniques for the classification of chromites in diamond exploration samples.Journal of Geochemical Exploration, Vol. 59, No. 3, Sept. pp. 233-250.Australia, South Africa, Swaziland, China, Russia, United StatesGeostatistics, classification, chromite, Diamond exploration, technology
DS1997-0445
1997
Griffin, W.L.Griffin, W.L., Moore, R.O., Ryan, Gurney, WinGeochemistry of magnesian ilmenite megacrysts from Southern african kimberlites #2Russian Geology and Geophysics, Vol. 38, No. 2, pp. 421-443.South Africa, Botswana, Namibia, LesothoGeochemistry, Megacrysts
DS1997-0542
1997
Griffin, W.L.Ionov, D., Griffin, W.L., O'Reilly, S.Y., Malkovets, V.Carbonate bearing mantle xenoliths in alkali basalts: phase mineral compositions, MetasomatismGeological Association of Canada (GAC) Abstracts, AustraliaXenoliths, Mantle carbonate Metasomatism
DS1997-0543
1997
Griffin, W.L.Ionov, D.A., Griffin, W.L., O'Reilly, S.Y.Volatile bearing minerals and lithophile trace elements in the uppermantle.Chemical Geol., Vol. 141, No. 3-4, Sept. 30, pp. 153-184.MantleGeochemistry, large-ion lithophile elements (LILE).
DS1997-1073
1997
Griffin, W.L.Sobolev, N.V., Kaminsky, F.V., Botkunova, A.I., Griffin, W.L., YefimovaMineral inclusions in diamonds from the Sputnik kimberlite pipe, YakutiaLithos, Vol. 39, No. 3-4, Feb. 1, pp. 135-158.Russia, YakutiaMineral chemistry, Diamond inclusions, mineralogy, Deposit - Sputnik
DS1998-0076
1998
Griffin, W.L.Barashkov, Yu.P., Griffin, W.L., Telnikova, S.B.Trace element composition of sulfide inclusions in garnets from the Udachnaya kimberlite pipe, Yakutia.Geochemistry International, Vol. 36, No. 12, Dec. 1 pp. 1147-53.Russia, YakutiaGeochemistry, Deposit - Udachnaya
DS1998-0106
1998
Griffin, W.L.Belousova, E., Griffin, W.L., O'Reilly, S.Y.Apatite: a sensitive indicator of crystallization environmentGemoc 1998 Annual Report, p. 20. abstractNorway, South Africa, Russia, AustraliaCarbonatite
DS1998-0107
1998
Griffin, W.L.Belousova, E.A., Griffin, W.L., O'Reilly, S.Y.Trace element composition and cathodluminescence properties of kimberliticzircons.7th International Kimberlite Conference Abstract, pp. 67-69.South Africa, Russia, Yakutia, AustraliaMineralogy - trace elements, Zircons
DS1998-0108
1998
Griffin, W.L.Belousova, E.A., Griffin, W.L., Pearson, N.J.Trace element composition and cathodluminescence properties of Southern african kimberlitic zircons.Mineralogical Magazine, Vol. 62, No. 3, June pp. 355-66.South AfricaDiamond inclusions, Mineral chemistry
DS1998-0184
1998
Griffin, W.L.Bulanova, G.P., Griffin, W.L., Kaminsky, F.V., DaviesDiamonds from Zarnitsa and Dalnaya kimberlites: their nature, growthhistory, lithospheric mantle source.7th International Kimberlite Conference Abstract, pp. 113-5.Russia, YakutiaDiamond morphology, Deposit - Zarnitsa, Dalnaya
DS1998-0185
1998
Griffin, W.L.Bulanova, G.P., Griffin, W.L., Ryan, C.G.Nucleation environment of diamonds from Yakutian kimberlitesMineralogical Magazine, Vol. 62, No. 3, June pp. 409-20.Russia, YakutiaDiamond morphology
DS1998-0306
1998
Griffin, W.L.Davies, R., Griffin, W.L., Pearson, N.J., Andrew, DoyleDiamonds from the Deep: Pipe DO 27, Slave Craton, Canada7th International Kimberlite Conference Abstract, pp. 170-172.Northwest TerritoriesDiamond inclusions, Deposit - Pipe DO-27
DS1998-0307
1998
Griffin, W.L.Davies, R.M., Griffin, W.L., O'Reilly, S.Y.Diamonds from the deep and shallowGemoc 1998 Annual Report, p. 19.Northwest Territories, AustraliaDiamond morphology, Diamond inclusions
DS1998-0308
1998
Griffin, W.L.Davies, R.M., O'Reilly, S.Y., Griffin, W.L.Dynamic growth structures in diamonds from Bingara, New South Wales7th International Kimberlite Conference Abstract, pp. 176-8.Australia, New South WalesDiamond morphology, Deposit - Bingara
DS1998-0309
1998
Griffin, W.L.Davies, R.M., O'Reilly, S.Y., Griffin, W.L.Characteristics of alluvial diamonds from Bingara and Wellington, EasternAustralia.7th International Kimberlite Conference Abstract, pp. 173-5.Australia, New South Wales, Eastern AustraliaAlluvials, Deposit - Bingara, Wellington
DS1998-0480
1998
Griffin, W.L.Gaul, O., O'Reilly, S.Y., Griffin, W.L.Lithosphere mapping in eastern Australia7th International Kimberlite Conference Abstract, pp. 245-7.AustraliaTectonics, Geothermometry
DS1998-0534
1998
Griffin, W.L.Griffin, W.L., Djomani, P., Natapov, L., O'Reilly, S.Y.Detecting lithosphere scale structures: Siberian PlatformGemoc 1998 Annual Report, p. 22-3. abstractRussia, SiberiaGeophysics - gravity, Mantle petrology
DS1998-0535
1998
Griffin, W.L.Griffin, W.L., Doyle, B.J., Ryan, Pearson, O'ReillyLithosphere structure and mantle terranes: Slave Craton, Canada7th International Kimberlite Conference Abstract, pp. 271-273.Northwest TerritoriesTerranes, xenoliths, Deposit - Ranch Lake, Jericho, Cross Lake
DS1998-0536
1998
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y.From the micro to the macro or: has the earth changed?Gemoc 1998 Annual Report, p. 24-5. abstractMantleGarnet xenocrysts, Archean, Proterozoic, Phanerozoic
DS1998-0537
1998
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Ryan, C.G.The composition of subcontinental lithospheric mantle: garnet basedestimates.Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 541-2.South Africa, RussiaSCLM geochemistry, xenoliths, Mean mantle compositions
DS1998-0538
1998
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Ryan, C.G., Gaul, IonovSecular variation in the composition of lithospheric mantle: geophysical and geodynamic implications.Structure EVol. Austral., American Geophysical Union (AGU) geodynamics Vol. 26, pp. 1-26.MantleGeophysics, geodynamics
DS1998-0539
1998
Griffin, W.L.Griffin, W.L., Win, T.T., Davies, R., Wathanakul ..Diamonds from Myanmar and Thailand: characteristics and possible origin7th International Kimberlite Conference Abstract, pp. 274-6.GlobalAlluvial diamonds, Diamond morphology
DS1998-0656
1998
Griffin, W.L.Ionov, D.A., Griffin, W.L., Reilly, S.Y.Garnet peridotite xenoliths in alkali basalts from Siberia and Mongolia: acomparison of lithospheric...7th International Kimberlite Conference Abstract, pp. 339-41.Russia, Siberia, Yakutia, Mongolia, BaikalCraton, mantle, xenoliths, Deposit - Udachnaya, VitiM.
DS1998-0759
1998
Griffin, W.L.Kivi, K., Griffin, W.L.Lithospheric mapping of the Slave Craton, northwest Territories, CanadaYellowknife Geoscience Forum Nov. 25-27, p. 69-70. abstractNorthwest TerritoriesCraton, Tectonics
DS1998-0927
1998
Griffin, W.L.Malkovets, V.G., Ionov, D.A., Griffin, W.L., O'ReillyA P-T composition cross section of spinel and garnet facies lithospheric mantle in the Minusa region.7th International Kimberlite Conference Abstract, pp. 543-5.Russia, SiberiaCraton -basanite, Deposit - Minusa region
DS1998-1065
1998
Griffin, W.L.Natapov, L., Griffin, W.L.Geodynamic controls on the distribution of Diamondiferous kimberlites7th International Kimberlite Conference Abstract, pp. 615-7.Russia, AngolaTectonics, Olenek, Lucappe, Kimberlite magmatism, hot spots
DS1998-1101
1998
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Are lithospheres forever? #2Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 1114-5.MantleLithosphere - SCLM.
DS1998-1102
1998
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L., Poudjom Djomani, Y.Are lithospheres forever? #17th. Kimberlite Conference abstract, pp. 646-8.MantleLithosphere mapping, Geophysics - seismics
DS1998-1140
1998
Griffin, W.L.Pearson, N.J., Griffin, W.L., Doyle, O'Reilly, KiviXenoliths from kimberlite pipes of the Lac de Gras area, Slave Craton, Canada.7th. Kimberlite Conference abstract, pp. 670-2.Northwest TerritoriesGeothermometry, Xenoliths
DS1998-1392
1998
Griffin, W.L.Spetsius, Z.V., Griffin, W.L.Trace element composition of garnet kelphites in xenoliths from Udachnayaas evidence of their origin.7th International Kimberlite Conference Abstract, pp. 853-5.Russia, SiberiaXenoliths, kelphitic rims, Deposit - Udachnaya
DS1998-1508
1998
Griffin, W.L.Van Achterbergh, E., Griffin, W.L., Shee, S.R., WyattNatural trace element distribution coefficients for garnet, clino-orthopyroxene: variations T and P.7th International Kimberlite Conference Abstract, pp. 934-6.South AfricaXenoliths, Metasomatism, Deposit - Wesselton
DS1998-1509
1998
Griffin, W.L.Van Achterbergh, E., Griffin, W.L., Steifenhofer, J.Xenoliths from the Letlhakane kimberlite: geochemistry and implications for mantle processes.7th International Kimberlite Conference Abstract, pp. 937-9.BotswanaHarzburgite, lherzolite, Metasomatism, Deposit - Latlhakane
DS1998-1611
1998
Griffin, W.L.Yao, S., Griffin, W.L., O'Reilly, S.Y.Trace elements in chromites from kimberlites and related rocks: relation to temperature and mantle comp.7th International Kimberlite Conference Abstract, pp. 980-82.MantlePetrogenetic indicator, genesis, Mantle Array chromites
DS1998-1625
1998
Griffin, W.L.Zhang, A., Griffin, W.L., Ryan, C.G., Andrew, A.Conditions of diamond formation beneath the Sino-Korean Craton:paragenesis, temperatures and isotopic cond.7th International Kimberlite Conference Abstract, pp. 992-4.China, LiaoningMineral inclusions, Deposit - Pipe # 50, Shengli #1, Hongqi # 6
DS1999-0160
1999
Griffin, W.L.Davies, R.M., O'Reilly, S.Y., Griffin, W.L.Diamonds from Wellington, New South Wales: insights into the origin of Eastern Australian diamonds.Mineralogical Magazine, Vol. 63, No. 4, Aug. pp. 447-71.Australia, New South WalesAlluvial, diamond inclusions, deformation, aggregation, Diamond morphology
DS1999-0265
1999
Griffin, W.L.Griffin, W.L. , Ryan, C.G., Ilupin, I.P.The Siberian lithosphere traverse: mantle terranes and the assemblyof the Siberian Craton.Tectonophysics, Vol. 310, No. 1-4, Sept. 15, pp. 1-36.Russia, SiberiaTectonics, lithosphere, Craton, terranes
DS1999-0266
1999
Griffin, W.L.Griffin, W.L., Doyle, B.J., Natapov, L.M.Layered mantle lithosphere in the Lac de Gras area, Slave Craton:composition, structure and origin.Journal of Petrology, Vol. 40, No. 5, May, pp. 705-28.Northwest TerritoriesMantle, Tectonics
DS1999-0267
1999
Griffin, W.L.Griffin, W.L., Fisher, N.I., O'Reilly, S.Y.chromium pyrope garnets in the lithospheric mantle: 1. Compositional systematic sand relations to tectonic...Journal of Petrology, Vol. 40, No. 5, May, pp. 679-704.MantleMineralogy - garnet, Tectonic setting
DS1999-0268
1999
Griffin, W.L.Griffin, W.L., Shee, S.R., Wyatt, B.A.Harzburgite to lherzolite and back again: metasomatic processes in ultramafic xenoliths from Wesselton ...Contributions to Mineralogy and Petrology, Vol. 134, No. 2-3, pp. 232=50.South AfricaMetasomatism, Deposit - Wesselton
DS1999-0276
1999
Griffin, W.L.Guo, J., Griffin, W.L., O'Reilly, S.Y.Geochemistry and origin of sulphide minerals in mantle xenoliths, Qilin, southeastern China.Journal of Petrology, Vol. 40, No. 7, July pp. 1125-50.China, southeastXenoliths, Geochemistry
DS1999-0363
1999
Griffin, W.L.Kivi, K., Griffin, W.L.Industry Academic alliance maps lithosphere of the Slave Craton, northwest Canada.Assocation of Exploration Geologists (AEG) 19th. Diamond Exploration Methods Case Histories, pp. 38-42.Northwest TerritoriesLithosphere, Xenoliths, diamond inclusions
DS1999-0814
1999
Griffin, W.L.Xu, X., O'Reilly, S.Y., Griffin, W.L.Reply: the geotherms of the lithosphere beneath Qilin, southeast China: are-appraisal and implications for P-T ...Lithos, Vol. 47, No. 3-4, July pp. 195-200.ChinaPyroxenites - iron rich, Lithosphere
DS1999-0828
1999
Griffin, W.L.Zhang, A., Griffin, W.L., Ryan, C.G., Andrew, A.S.Conditions of diamond formation beneath Liaoning and Shandong Provinces: parageneses, temperatures... carbon7th International Kimberlite Conference Nixon, Vol. 2, pp. 940-47.China, Shandong, LiaoningGeochronology, diamond inclusions, major element analys, Deposit - Mengyin
DS2000-0011
2000
Griffin, W.L.Alard, O., Griffin, W.L., O'Reilly, S.Y.Non chondritic distribution of the highly siderphile elements in mantle sulphides.Nature, Vol. 407, No. 6806, Oct. 19, p.891-3.MantleSulphides
DS2000-0320
2000
Griffin, W.L.Gaul, O.F., Griffin, W.L., Pearson, N.J.Mapping olivine composition in the lithospheric mantleEarth and Planetary Science Letters, Vol. 182, No. 3-4, Nov. 15, pp. 223-35.MantleOlivine
DS2000-0363
2000
Griffin, W.L.Griffin, W.L., Pearson, N., Bolousova, Van AchterberghThe hafnium isotope composition of cratonic mantle: LAM MC ICPMS analysis of zircon megacrysts in kimberlites.Geochimica et Cosmochimica Acta, Vol. 64, pp. 133-47.AustraliaGeochronology
DS2000-0470
2000
Griffin, W.L.Karmalkar, N.R., Griffin, W.L., O'Reilly, S.Y.Ultramafic xenoliths from Kutch Northwest India: plume related mantle samples?International Geology Review, Vol. 42, No. 5, may pp. 416-44.IndiaMantle - xenoliths, Deposit - Kutch area
DS2000-0471
2000
Griffin, W.L.Karmalker, N.R., Griffin, W.L., O'Reilly, S.Y.Ultramafic xenoliths from Kutch ( NW India): plume related mantle samples?International Geology Review, Vol. 42, pp. 416-444.Northwest IndiaBlank
DS2000-0472
2000
Griffin, W.L.Karmnacher, N.R., Griffin, W.L., O'Reilly, S.Y.Ultramafic xenoliths from Kutch ( northwest India): plume related mantle samples?International Geology Review, Vol. 42, pp. 416-44.IndiaMantle plumes, Xenoliths
DS2000-0735
2000
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Apatite in the mantle: implications for metasomatic processes and high heat production Phanerozoic mantleLithos, Vol. 53, No. 3-4, Sept. pp. 217-32.Mantle, Australia, Alaska, GermanyMetasomatism, Phanerozoic, Apatite
DS2001-0102
2001
Griffin, W.L.Belousova, E.A., Griffin, W.L., Shee, Jackson, O'ReillyTwo age populations of zircons from the Timber Creek kimberlites, as determined by laser ablation ICP MSAustralian Journal of Earth Sciences, Vol. 48, No. 5, Oct. pp. 757-766.AustraliaGeochronology, Deposit - Timber Creek
DS2001-0256
2001
Griffin, W.L.Djomani, Y.H.P., Griffin, W.L., O'Reilly, S.Y., et al.Lithospheric boundaries on the eastern Siberian platformPreview (Australian Society of Exploration Geophysics), 15th. Conference abstract p. 94.RussiaGeophysics - gravity
DS2001-0413
2001
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Natapov, L.M.Lithospheric mantle beneath southern Africa: composition, structure and evolution.Slave-Kaapvaal Workshop, Sept. Ottawa, 6p. abstractSouth AfricaGeochemistry, geochronology, Tomography - Kalahari supercraton
DS2001-0746
2001
Griffin, W.L.McCammon, C.A., Griffin, W.L., Shee, S.R., O'Neill, H.R.Oxidation during metasomatism in ultramafic xenoliths from Wesselton kimberlite: implications for survival..Contributions to Mineralogy and Petrology, Vol. 141, No. 3, June, pp. 287-296.South AfricaXenoliths, diamond survival, Deposit - Wesselton
DS2001-0873
2001
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L., Poudjom Djomani, MorganAre lithospheres forever? Tracking changes in subcontinental lithospheric mantle through time.Gsa Today, Vol. 11, No. 4, April pp. 4-9.MantleLithosphere - tomography, boundary
DS2001-1000
2001
Griffin, W.L.Ryan, C.G., Jamieson, D.N., Griffin, W.L., CrippsThe new CSIRO GEMOC nuclear microprobe: first results, performance and recent applications.Nuclear Institute Methods Phys. Res., Vol. B 181, pp. 12-19.GlobalProton microprobe
DS2001-1179
2001
Griffin, W.L.Van Achterbergh, A.E., Griffin, W.L., Stiefenhofer, J.Metasomatism in mantle xenoliths from the Letlhakane kimberlites: estimation of element fluxes.Contributions to Mineralogy and Petrology, Vol. 141, No. 4, pp. 397-414.BotswanaXenoliths - alteration, Deposit - Letlhakane
DS2002-0015
2002
Griffin, W.L.Alard, O., Griffin, W.L., Pearson, N.J., Lorand, J.P., O'Reilly, S.Y.New insights into the Re Os systematics of sub-continental lithospheric mantle from an insitu analysis of sulphides.Earth and Planetary Science Letters, Vol. 203, 3, pp. 651-663.MantleGeochronology
DS2002-0035
2002
Griffin, W.L.Andersen, T., Griffin, W.L., Pearson, N.J.Crustal evolution in the southwest part of the Baltic Shield: the Hf isotope evidenceJournal of Petrology, Vol. 43, 9, Sept.pp. 1725-48.Baltic Shield, NorwayTectonics, Geochronology
DS2002-0136
2002
Griffin, W.L.Belousova, E.A., Griffin, W.L., O'Reilly, S.Y., Fisher, N.I.Apatite as an indicator mineral for mineral exploration: trace element compositions and their relationship to host rock type.Journal of Geochemical Exploration, Vol.76,1,July pp. 45-69.MantleGeochemistry - indicator minerals
DS2002-0137
2002
Griffin, W.L.Belousova, E.A., Griffin, W.L., O'Reilly, S.Y., Fisher, N.I.Igneous zircon: trace element composition as an indicator of source rock typeContributions to Mineralogy and Petrology, Vol. 143, 5, pp.587-601.MantleUHP, Geochemistry - indicator minerals
DS2002-0215
2002
Griffin, W.L.Brueckner, H.K., Carswell, D.A., Griffin, W.L.Paleozoic diamonds with a Precambrian peridotite lens in UHP gneisses of the Norwegian Caledonides.Earth and Planetary Science Letters, Vol. 203, 3-4, pp. 805-16.Scandinavia, NorwayUHP - peridotites
DS2002-0356
2002
Griffin, W.L.Davies, R.M., O'Reilly, S.Y., Griffin, W.L.Multiple origins of alluvial diamonds from New South Wales, AustraliaEconomic Geology, Vol. 97,1,Jan-Feb.pp. 109-124., Vol. 97,1,Jan-Feb.pp. 109-124.Australia, New South WalesAlluvials, placers, genesis
DS2002-0357
2002
Griffin, W.L.Davies, R.M., O'Reilly, S.Y., Griffin, W.L.Multiple origins of alluvial diamonds from New South Wales, AustraliaEconomic Geology, Vol. 97,1,Jan-Feb.pp. 109-124., Vol. 97,1,Jan-Feb.pp. 109-124.Australia, New South WalesAlluvials, placers, genesis
DS2002-0614
2002
Griffin, W.L.Griffin, W.L., Wang, X., Jackson, Pearson, O'Reilly, XuZircon chemistry and magma mixing, SE China: in situ analysis of Hf isotopes, Tonglu and Pingtan complexes.Lithos, Vol.61, No.1-4, pp. 237-69., Vol.61, No.1-4, pp. 237-69.China, SoutheastGeochemistry - magma mixing, Geochronology
DS2002-0615
2002
Griffin, W.L.Griffin, W.L., Wang, X., Jackson, Pearson, O'Reilly, XuZircon chemistry and magma mixing, SE China: in situ analysis of Hf isotopes, Tonglu and Pingtan complexes.Lithos, Vol.61, No.1-4, pp. 237-69., Vol.61, No.1-4, pp. 237-69.China, SoutheastGeochemistry - magma mixing, Geochronology
DS2002-1636
2002
Griffin, W.L.Van Achterbergh, E., Griffin, W.L., Ryan, C.G., O'Reilly, S.Y., Pearson, N.J.Subduction signature for quenched carbonatites from the deep lithosphereGeology, Vol.30,8,Aug.pp.743-6.MantleSubduction, Carbonatite
DS2003-0049
2003
Griffin, W.L.Aulbach, S., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.The lithospheric mantle beneath the Buffalo Head Terrane, Alberta: xenoliths from the8 Ikc Www.venuewest.com/8ikc/program.htm, Session 4, AbstractAlbertaMantle geochemistry, Geochronology
DS2003-0050
2003
Griffin, W.L.Aulbach, S., Griffin, W.L., Pearson, N.J., O'Reilly, S.Y., Kivi, K., Doyle, B.J.Origins of eclogites beneath the central Slave Craton8ikc, Www.venuewest.com/8ikc/program.htm, Session 2, POSTER abstractNorthwest TerritoriesEclogites and Diamonds
DS2003-0314
2003
Griffin, W.L.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., Andrew, A.S.Unusual mineral inclusions and carbon isotopes of alluvial diamonds from BingaraLithos, Vol. 69, 1-2, pp. 51-66.AustraliaDeposit - Bingara
DS2003-0315
2003
Griffin, W.L.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., Andrew, A.S.Unusual mineral inclusions and carbon isotopes of alluvial diamonds from BingaraLithos, Vol. 69, 1-2, July, pp. 1-67.Australia, eastern AustraliaDiamond inclusions, geochronology, Deposit - Bingara
DS2003-0316
2003
Griffin, W.L.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., Doyle, B.J.Geochemical characteristics of microdiamonds from kimberlites at Lac de Gras, Central8 Ikc Www.venuewest.com/8ikc/program.htm, Session 3, AbstractNorthwest TerritoriesDiamonds - micro, Geochemistry
DS2003-0317
2003
Griffin, W.L.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.Inclusions in diamonds from the K10 and K14 kimberlites, Buffalo Hills, Alberta8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractAlbertaDiamonds - inclusions
DS2003-0502
2003
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Abe, N., Aulbach, S., Davies, R.M., Pearson, N.J.The origin and evolution of Archean lithospheric mantlePrecambrian Research, Vol. 127, 1-2, Nov. pp. 19-41.China, South Africa, Siberia, Northwest Territories, BoGeochemistry, SCLM, continental, Archon, metasomatism
DS2003-0503
2003
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Doyle, B.J., Kivi, K.Lithospheric mapping beneath the North American plate8 Ikc Www.venuewest.com/8ikc/program.htm, Session 9, AbstractNorthwest Territories, Greenland, LabradorCraton studies, SLCM
DS2003-0504
2003
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Natapov, L.M., Ryan, C.G.The evolution of lithospheric mantle beneath the Kalahari Craton and its marginsLithos, Vol. 71, 2-4, pp. 215-241.South Africa, BotswanaTectonics
DS2003-0757
2003
Griffin, W.L.Kuligin, S.S., Malkovets, V.G., Pkhilenko, N.P., Vavilov, M.A., Griffin, W.L.Mineralogical and geochemical characteristics of a unique mantle xenoliths from the8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractRussia, YakutiaMantle geochemistry, Deposit - Udachnaya
DS2003-0870
2003
Griffin, W.L.Malkovets, V.G., Taylor, L.A., Griffin, W.L., O'Reilly, S., Pokhilenko, N.P.Eclogites from the Grib kimberlite pipe, Arkangelsk, Russia8ikc, Www.venuewest.com/8ikc/program.htm, Session 2, POSTER abstractRussia, ArkangelskEclogites and Diamonds, Deposit - Grib
DS2003-1035
2003
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Taking the pulse of the Earth: lithosphere events tracked by in situ geochronology8 Ikc Www.venuewest.com/8ikc/program.htm, Session 9, AbstractSouth AfricaCraton studies, Kaapvaal, terranes
DS2003-1051
2003
Griffin, W.L.Pearson, N.J., Griffin, W.L., O'Reilly, S.Y., Delpech, G.Magnesium isotopic compositions of olivine from the lithospheric mantle8 Ikc Www.venuewest.com/8ikc/program.htm, Session 4, AbstractRussia, Siberia, South Africa, Northwest TerritoriesMantle geochemistry
DS2003-1092
2003
Griffin, W.L.Pokhilenko, N.P., Griffin, W.L., Shimizu, N., McLean, R.C., Malkovets, V.G.Pyropes and chromites of the Snap Lake King Lake kimberlite dyke system in relation8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, POSTER abstractNorthwest TerritoriesDeposit - Snap Lake King Lake
DS2003-1097
2003
Griffin, W.L.Poudjom Dojomani, Y.H., O'Reilly, S.Y., Griffin, W.L., Doyle, B.J.Geophysical analysis of the lithosphere beneath the Slave Craton8 Ikc Www.venuewest.com/8ikc/program.htm, Session 9, POSTER abstractNorthwest TerritoriesGeophysics
DS2003-1151
2003
Griffin, W.L.Rege, S., Davies, R.M., Griffin, W.L., Jackson, S., O'Reilly, S.Y.Trace element analysis of diamonds by LAM ICPMS: preliminary results8 Ikc Www.venuewest.com/8ikc/program.htm, Session 3, AbstractRussia, Siberia, Australia, Brazil, Northwest TerritoriesDiamonds - database 115, Geochemistry
DS2003-1406
2003
Griffin, W.L.Van Achetrbergh, E., Ryan, C.G., Griffin, W.L., O'Reilly, S.Y.Natural trace element distribution between immiscible silicate and carbonate melts8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, POSTER abstractNorthwest TerritoriesDeposit - A 154N Lac de Gras
DS2003-1407
2003
Griffin, W.L.Van Achterbergh, E., Griffin, W.L., O'Reilly, S.Y., Ryan, C.G., Pearson, N.J.Melt inclusions from the deep Slave lithosphere: constraints on the origin and evolution8 Ikc Www.venuewest.com/8ikc/program.htm, Session 3, AbstractNorthwest TerritoriesDiamonds - melting
DS2003-1447
2003
Griffin, W.L.Wang, K.L., O'Reilly, S.Y., Griffin, W.L., Chung, S.L., Pearson, N.J.Proterozoic mantle lithosphere beneath the extended margin of the South Chin a block:Geology, Vol. 31, 8, pp. 709-712.ChinaGeochronology
DS2003-1448
2003
Griffin, W.L.Wang, K.L., O'Reilly, S.Y., Griffin, W.L., Chung, S-L., Juang, W-S.Geochemical characteristics of mantle xenoliths from Penghu Island, Taiwan Straits, SE8 Ikc Www.venuewest.com/8ikc/program.htm, Session 9, POSTER abstractChina, AsiaBlank
DS2003-1505
2003
Griffin, W.L.Wyatt, B.A., Mitchell, M., Shee, S.R., Griffin, W.L., Tomlinson, N., White, B.The Brockman Creek kimberlite, east Pilbara, Australia8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractAustraliaDeposit - Brockman Creek
DS2003-1512
2003
Griffin, W.L.Xu, X., O'Reilly, S.Y., Griffin, W.L., Zhou, X.Enrichment of upper mantle peridotite: petrological, trace element and isotopic evidenceChemical Geology, Vol. 198, 3-4, pp. 163-188.ChinaPetrology, Geochronology
DS2003-1513
2003
Griffin, W.L.Xu, X., O'Reilly, S.Y., Griffin, W.L., Zhou, X.Enrichment of upper mantle peridotite: petrological, trace element and isotopic evidenceChemical Geology, Vol. 198, 3-4, August 15, pp. 163-188.China, southeastBasalts, Nushan, Mingxi, Geochronology
DS2003-1535
2003
Griffin, W.L.Yu, J.H., O'Reilly, S.Y., Griffin, W.L., Xu, X., Zhang, M., Zhou, X.The thermal state and composition of the lithospheric mantle beneath the LeizhouJournal of Volcanology and Geothermal Research, Vol. 122, 3-4, pp. 165-89.China, southGeothermometry
DS2003-1536
2003
Griffin, W.L.Yu, J-H., O'Reilly, S.Y., Griffin, W.L., Xu, X., Zhang, M., Zhou, X.The thermal state and composition of the lithospheric mantle beneath the LeizhouJournal of Volcanology and Geothermal Research, Vol. April 1, pp. 165-189.ChinaMetapyroxenites, xenoliths
DS2003-1537
2003
Griffin, W.L.Yu, J-H., Xu, X., O'Reilly, S.Y., Griffin, W.L., Zhang, M.Granulite xenoliths from Cenozoic basalts in SE Chin a provide geochemical fingerprintsLithos, Vol. 67, 1-2, March pp. 77-102.China, southeastXenoliths, Geochemistry
DS200412-0033
2004
Griffin, W.L.Andersen, T., Griffin, W.L.Lu Hf and U Pb isotope systematics of zircons from the Storgangen intrusion, Rogaland Intrusive Complex, SW Norway: implicationsLithos, Vol. 73, 3-4, April pp. 271-288.Europe, NorwayGeochronology, lower crust
DS200412-0034
2004
Griffin, W.L.Andersen, T., Griffin, W.L., Jackson, S.E., Knudsen, T.L., Pearson, N.J.Mid-Proterozoic magmatic arc evolution at the southwest margin of the Baltic Shield.Lithos, Vol. 73, 3-4, April pp. 289-318.Europe, Norway, Baltic ShieldMagmatism, Laser ablation, geochronology
DS200412-0074
2003
Griffin, W.L.Aulbach, S., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.The lithospheric mantle beneath the Buffalo Head Terrane, Alberta: xenoliths from the Buffalo Hills kimberlites.8 IKC Program, Session 4, AbstractCanada, AlbertaMantle geochemistry Geochronology
DS200412-0075
2004
Griffin, W.L.Aulbach, S., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.Genesis and evolution of the lithospheric mantle beneath the Buffalo Head Terrane, Alberta ( Canada).Lithos, Vol. 77, 1-4, Sept. pp. 413-451.Canada, AlbertaTrace elements, Os Hf isotopes, geochronology, metasoma
DS200412-0076
2004
Griffin, W.L.Aulbach, S., Griffin, W.L., Pearson, N.J., O'Reilly, S.Y., Kivi, K., Doyle, B.J.Mantle formation and evolution, Slave Craton: constraints from HSE abundances and Re Os isotope systematics of sulfide inclusionChemical Geology, Vol. 208, 1-4, pp. 61-88.Canada, Northwest TerritoriesGeochronology, Lac de Gras, metasomatism, melt-deletion
DS200412-0145
2004
Griffin, W.L.Beyer, E.E., Brueckner, H.K., Griffin, W.L.,O'Reilly, S.Y., Graham, S.Archean mantle fragments in Proterozoic crust, Western Gneiss region, Norway.Geology, Vol. 32, 7, July pp. 609-612.Europe, NorwayGarnet peridotites
DS200412-0414
2003
Griffin, W.L.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., Andrew, A.S.Unusual mineral inclusions and carbon isotopes of alluvial diamonds from Bingara, eastern Australia.Lithos, Vol. 69, 1-2, pp. 51-66.AustraliaDiamond inclusions, Bingara
DS200412-0415
2003
Griffin, W.L.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., Doyle, B.J.Geochemical characteristics of microdiamonds from kimberlites at Lac de Gras, Central Slave Craton, Canada.8 IKC Program, Session 3, AbstractCanada, Northwest TerritoriesDiamonds - micro, geochemistry
DS200412-0416
2004
Griffin, W.L.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., Doyle, B.J.Mineral inclusions and geochemical characteristics of microdiamonds from the DO27, A154, A21, A418, DO18, DD17 and Ranch Lake kiLithos, Vol. 77, 1-4, Sept. pp. 39-55.Canada, Northwest TerritoriesSlave Craton, diamond inclusions, C isotopes, N content
DS200412-0417
2004
Griffin, W.L.Davies, R.M., Griffin, W.L., O'Reilly, S.Y., McCandless, T.E.Inclusions in diamonds from K14 and K10 kimberlites, Buffalo Hills, Alberta, Canada: diamond growth in a plume?Lithos, Vol. 77, 1-4, Sept. pp. 99-111.Canada, AlbertaDiamond inclusions, Carbon isotopes, nitrogen aggregati
DS200412-0617
2004
Griffin, W.L.Gaul, O.F., O'Reilly, S.Y., Griffin, W.L.Lithosphere structure and evolution in southeastern Australia.Hillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological Society America Memoir, No. 372, pp. 185-202.AustraliaTectonics
DS200412-0720
2004
Griffin, W.L.Griffin, W.L., Belousova, E.A., Shee, S.R., Pearson, N.J., O'Reilly, S.Y.Archean crustal evolution in the northern Yilgarn Craton: U Pb and Hf isotope evidence from detrital zircons.Precambrian Research, Vol. 131, 3-4, pp. 231-282.AustraliaGeochronology - Yilgarn
DS200412-0721
2002
Griffin, W.L.Griffin, W.L., Fisher, N.I., Friedman, J.H., O'Reilly, S.Y., Ryan, C.G.Cr pyrope garnets in the lithospheric mantle 2: compositional populations and their distribution in time and space.Geochemistry, Geophysics, Geosystems: G3, Vol. 3, 12, 1073 DOI 10.1029/2002 GC000298MantleGeochemistry - pyropes
DS200412-0722
2004
Griffin, W.L.Griffin, W.L., Graham, S., O'Reilly, S.Y., Pearson, N.J.Lithosphere evolution beneath the Kaapvaal Craton: Re-Os systematics of sulfides in mantle derived peridotites.Chemical Geology, Vol. 208, 1-4, pp. 89-118.Africa, South Africa, LesothoGeochronology, Finsch, Kimberley, Jagersfontein
DS200412-0723
2003
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Abe, N., Aulbach, S., Davies, R.M., Pearson, N.J., Doyle, B.J.,Kivi, K.The origin and evolution of Archean lithospheric mantle.Precambrian Research, Vol. 127, 1-2, Nov. pp. 19-41.China, Africa, Russia, Canada, Northwest TerritoriesGeochemistry, SCLM, continental, Archon, metasomatism
DS200412-0724
2003
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Doyle, B.J., Kivi, K.Lithospheric mapping beneath the North American plate.8 IKC Program, Session 9, AbstractCanada, Northwest Territories, Quebec, Labrador, Europe, GreenlandCraton studies, SLCM
DS200412-0725
2004
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Doyle, B.J., Pearson, N.J., Coopersmith, H., Kivi, K., Melkovets, V., PokhilenkLithosphere mapping beneath the North American plate.Lithos, Vol. 77, 1-4, Sept. pp. 873-922.Canada, Northwest Territories, Europe, GreenlandArchon, Proton, Tecton, Slave Craton, Kapuskasing Struc
DS200412-0726
2003
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Natapov, L.M., Ryan, C.G.The evolution of lithospheric mantle beneath the Kalahari Craton and its margins.Lithos, Vol. 71, 2-4, pp. 215-241.Africa, South Africa, BotswanaTectonics
DS200412-0956
2000
Griffin, W.L.Karmalker, N.R., Griffin, W.L., O'Reilly, S.Y.Ultramafic xenoliths from Kutch ( NW India): plume related mantle samples?International Geology Review, Vol. 42, pp. 416-444.IndiaXenoliths
DS200412-1049
2003
Griffin, W.L.Kostrovitsky, S.I., Verichev, E.M., Garanin, V.K., Suvorova, L.V., Aschepkov, I.V., Mlovets, V., Griffin, W.L.Megacrysts from the Grib kimberlite Arkangelsk Province.8 IKC Program, Session 7, POSTER abstractRussia, Kola Peninsula, ArchangelKimberlite petrogenesis Deposit - Grib
DS200412-1476
2003
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Taking the pulse of the Earth: lithosphere events tracked by in situ geochronology.8 IKC Program, Session 9, AbstractAfrica, South AfricaCraton studies Kaapvaal, terranes
DS200412-1477
1992
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Nature of the east Australian lithosphere.In: Intraplate volcanism in eastern Australia and New Zealand, ed. R.W. Johnson, Cambridge University Press, pp. 290-297.Mantle, Australia, New South WalesGeophysics - seismics, magnetics
DS200412-1511
2003
Griffin, W.L.Pearson, N.J., Griffin, W.L., O'Reilly, S.Y., Delpech, G.Magnesium isotopic compositions of olivine from the lithospheric mantle.8 IKC Program, Session 4, AbstractRussia, Siberia, Canada, Northwest territories, Africa, South AfricaMantle geochemistry
DS200412-1563
2003
Griffin, W.L.Pokhilenko, N.P., Griffin, W.L., Shimizu, N., McLean, R.C., Malkovets, V.G., Pokhilenko, L.N., Malygina, E.V.Pyropes and chromites of the Snap Lake King Lake kimberlite dyke system in relation to the problem of the southern Slave Craton8 IKC Program, Session 6, POSTER abstractCanada, Northwest TerritoriesMantle petrology Deposit - Snap Lake King Lake
DS200412-1572
2003
Griffin, W.L.Poudjom Dojomani, Y.H., O'Reilly, S.Y., Griffin, W.L., Doyle, B.J.Geophysical analysis of the lithosphere beneath the Slave Craton.8 IKC Program, Session 9, POSTER abstractCanada, Northwest TerritoriesCraton studies Geophysics
DS200412-1648
2003
Griffin, W.L.Rege, S., Davies, R.M., Griffin, W.L., Jackson, S., O'Reilly, S.Y.Trace element analysis of diamonds by LAM ICPMS: preliminary results.8 IKC Program, Session 3, AbstractRussia, Siberia, AustraliaDiamonds - database 115 Geochemistry
DS200412-2032
2003
Griffin, W.L.Van Achetrbergh, E., Ryan, C.G., Griffin, W.L., O'Reilly, S.Y.Natural trace element distribution between immiscible silicate and carbonate melts imaged by nuclear microprobe.8 IKC Program, Session 7, POSTER abstractCanada, Northwest TerritoriesKimberlite petrogenesis Deposit - A 154N Lac de Gras
DS200412-2033
2003
Griffin, W.L.Van Achterbergh, E., Griffin, W.L., O'Reilly, S.Y., Ryan, C.G., Pearson, N.J., Kivi, K., Doyle, B.J.Melt inclusions from the deep Slave lithosphere: constraints on the origin and evolution of mantle derived carbonatite and kimbe8 IKC Program, Session 3, AbstractCanada, Northwest TerritoriesDiamonds - melting
DS200412-2080
2003
Griffin, W.L.Wang, K.L., O'Reilly, S.Y., Griffin, W.L., Chung, S.L., Pearson, N.J.Proterozoic mantle lithosphere beneath the extended margin of the South Chin a block: in situ Re Os evidence.Geology, Vol. 31, 8, pp. 709-712.ChinaGeochronology
DS200412-2081
2003
Griffin, W.L.Wang, K.L., O'Reilly, S.Y., Griffin, W.L., Chung, S-L., Juang, W-S.Geochemical characteristics of mantle xenoliths from Penghu Island, Taiwan Straits, SE Asian margin.8 IKC Program, Session 9, POSTER abstractChina, AsiaCraton studies
DS200412-2084
2004
Griffin, W.L.Wang, X., Griffin, W.L.Unusual Hf contents in metamorphic zircon from coesite bearing eclogites of the Dabie Mountains, east central China: implicationJournal of Metamorphic Geology, Vol. 22, 7, pp. 629-637.ChinaUHP - metamorphism, eclogites
DS200412-2152
2003
Griffin, W.L.Wyatt, B.A., Mitchell, M., Shee, S.R., Griffin, W.L., Tomlinson, N., White, B.The Brockman Creek kimberlite, east Pilbara, Australia.8 IKC Program, Session 8, POSTER abstractAustraliaDiamond exploration Deposit - Brockman Creek
DS200412-2161
2003
Griffin, W.L.Xu, X., O'Reilly, S.Y., Griffin, W.L., Zhou, X.Enrichment of upper mantle peridotite: petrological, trace element and isotopic evidence in xenoliths from SE China.Chemical Geology, Vol. 198, 3-4, August 15, pp. 163-188.ChinaBasalts, Nushan, Mingxi, geochronology
DS200412-2190
2003
Griffin, W.L.Yu, J-H., O'Reilly, S.Y., Griffin, W.L., Xu, X., Zhang, M., Zhou, X.The thermal state and composition of the lithospheric mantle beneath the Leizhou Peninsula, south China.Journal of Volcanology and Geothermal Research, Vol. April 1, pp. 165-189.ChinaMetapyroxenites, xenoliths
DS200412-2191
2004
Griffin, W.L.Yu, J-H., Xu, X., O'Reilly, S.Y., Griffin, W.L., Zhang, M.Granulite xenoliths from Cenozoic basalts in SE Chin a provide geochemical fingerprints to distinguish lower crust terranes fromLithos, Vol. 73, 1-2, March, pp. 135-144.ChinaTectonics, geochemistry
DS200412-2222
2004
Griffin, W.L.Zheng, J., Griffin, W.L., O'Reilly, S.Y., Lu, F., Wang, C., Zhang, M., Li, M.3.6 Ga lower crust in central Chin a: new evidence on the assembly of the North Chin a craton.Geology, Vol. 32, 3, Mar. pp. 229-232.ChinaGeochronology, early Archean
DS200412-2223
2004
Griffin, W.L.Zheng, J., Griffin, W.L., O'Reilly, S.Y., Lu, F., Yu, C., Zhang, M., Li, H.U Pb and Hf isotope analysis of zircons in mafic xenoliths from Fuxian kimberlites: evolution of the lower crust beneath the NorContributions to Mineralogy and Petrology, Vol. 148, 1, pp. 79-103.ChinaGeochronology - Fuxian
DS200412-2224
2004
Griffin, W.L.Zheng, J., O'Reilly, S.Y., Griffin, W.L., Zhang, M., Lu, F., Liu, G.Nature and evolution of Mesozoic Cenozoic lithospheric mantle beneath the Cathaysia block, southeast China.Lithos, Vol. 74, 1-2, pp. 41-65.ChinaTectonics, Anyuan lamprophyres
DS200512-0004
2004
Griffin, W.L.Afanasiev, V.P., Griffin, W.L., Natapov, L.M., Zinchuk, N.N., Matukhin, R.G., Mikrtychiyan, G.A.Diamond prospects in the southwestern flank of the Tungusk synclise.Geology of Ore Deposits, Vol. 47, 1, pp. 45-62.Russia, YakutiaDaldyn, Tychany, geochemistry
DS200512-0008
2005
Griffin, W.L.Alard, O., Luguet, A., Pearson, N.J., Griffin, W.L., Lorand, J.P., Gannoun, A., Burton, K.W., O'Reilly, S.Y.In situ Os isotopes in abyssal peridotites bridge the isotopic gap between MORBS and their source mantle.Nature, Vol. 436, No. 7053, Aug. 18, pp. 1005-1108.MantleGeochronology
DS200512-0040
2005
Griffin, W.L.Aulbach, S., Griffin, W.L., Pearson, N.J., O'Reilly, S.Y., Kivi, K.Origin and evolution of the lithospheric mantle beneath the central Slave Craton, Canada.GAC Annual Meeting Halifax May 15-19, Abstract 1p.Canada, Northwest TerritoriesGeochronology, Lac de Gras, metasomatism
DS200512-0141
2005
Griffin, W.L.Carswell, D.A., Griffin, W.L.Calculation of equilibriation conditions for garnet granulite and garnet websterite nodules in African kimberlite pipes.Mineralogy and Petrology, Vol. 28, 3, pp. 229-244.Africa, South AfricaGeothermometry, nodules
DS200512-0166
2005
Griffin, W.L.Choukroun, M., O'Reilly, S., Griffin, W.L., Pearson, N.J., Dawson, J.B.Hf isotopes of MARID (mica amphibole rutile ilmenite diopside) rutile trace metasomatic processes in the lithospheric mantle.Geology, Vol. 33, 1, Jan. pp. 45-48.Africa, South AfricaKimberley, metasomatism, xenoliths
DS200512-0184
2004
Griffin, W.L.Condie, K.C., Cox, J., O'Reilly, S.Y., Griffin, W.L., Kerrich, R.Definition of high field strength and rare elements in mantle and lower crustal xenoliths from the SE United States: the role of grain boundary phases.Geochimica et Cosmochimica Acta, Vol. 68, 19, pp. 3919-3942.United States, AppalachiaREE geochemistry
DS200512-0234
2005
Griffin, W.L.Djomani, Y.H.P., O'Reilly, S.Y., Griffin, W.L., Natapov, L.M., Pearson, N.J., Doyle, B.J.Variations of the effective elastic thickness (Te) and structure of the lithosphere beneath the Slave Province, Canada.Exploration Geophysics, Vol. 36, 3, pp. 266-271.Canada, Northwest TerritoriesGeophysics - seismics, telurics
DS200512-0369
2005
Griffin, W.L.Griffin, W.L., Natapov, L.M., O Reilly, S.Y., Van Acterbergh, E., Cherenkova, A.F., Cherenkov, V.G.The Kharamai kimberlite field, Siberia: modification of the lithospheric mantle by the Siberian Trap event.Lithos, Vol. 81, 1-4, pp. 167-187.Russia, SiberiaMetasomatism
DS200512-0370
2005
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y.Upper mantle composition: tools for smarter diamond exploration.Mineral deposit Research: Meeting the Global Challenge. 8th Biennial SGA Beijing, Aug. 18-22, 2005. Springer, Chapter 1-2, pp. 7-10.Mantle, Africa, Russia, CanadaSCLM, magmas
DS200512-0496
2005
Griffin, W.L.Karmalkar, N.R., Rege, S., Griffin, W.L., O'Reilly, S.Y.Alkaline magmatism from Kutch, NW India: implications for plume lithosphere interaction.Lithos, Vol. 81, 1-4, April pp. 101-119.IndiaDeccan Volcanic Province, Reunion plume, metasomatism
DS200512-0813
2005
Griffin, W.L.O'Reilly, S.Y., Hronsky, J., Griffin, W.L., Begg, G.The evolution of lithospheric domains: a new framework to enhance mineral exploration targeting.Mineral deposit Research: Meeting the Global Challenge. 8th Biennial SGA Beijing, Aug. 18-22, 2005. Springer, Chapter 1-11, pp. 41-44.MantleTectonics
DS200512-0972
2002
Griffin, W.L.Shchukin, V.S., Sablukova, S.M., Sablukova, L.I., Belousova,E.A., Griffin, W.L.Late Vendian aerial alkaline volcanism of rift type in the Zimny Bereg kimberlite area, Arkangelsk Diamondiferous province.Deep Seated Magmatism, magmatism sources and the problem of plumes., pp. 203-212.Russia, Kola Peninsula, ArchangelAlkalic
DS200512-1007
2005
Griffin, W.L.Smith, D., Griffin, W.L.Garnetite xenoliths and mantle water interactions below the Colorado Plateau southwestern United States.Journal of Petrology, Adanvced accessUnited States, ArizonaDiatremes, metasomatism, subduction
DS200512-1008
2005
Griffin, W.L.Smith, D., Griffin, W.L.Garnetite xenoliths and mantle: water interactions below the Colorado Plateau, southwestern United States.Journal of Petrology, Vol. 46, 9, pp. 1901-1924.United States, Colorado PlateauXenoliths
DS200512-1009
2005
Griffin, W.L.Smith, D., Griffin, W.L.Garnetite xenoliths and mantle water interactions below the Colorado Plateau, southwestern United States.Journal of Petrology, Vol. 46, 9, Sept. pp. 1901-9124.United States, Colorado PlateauXenoliths
DS200512-1209
2005
Griffin, W.L.Xu, X., O'Reilly, S.Y., Griffin, W.L., Deng, P., Pearson, N.J.Relict Proterozoic basement in the Nanling Mountains (SE China) and its tectonothermal.Tectonics, Vol. 24, 2, TC2003001652ChinaGeothermometry
DS200512-1247
2005
Griffin, W.L.Zhang, R.Y., Liou, J.G., Zheng, J-P., Griffin, W.L., Yui, T-F, O'Reilly, S.Y.Petrogenesis of the Yangkou layered garnet peridotite complex, Sulu UHP terrane, China.American Mineralogist, Vol. 90, pp. 801-813.ChinaUHP
DS200512-1259
2005
Griffin, W.L.Zheng, J., Griffin, W.L., O Reilly, S.Y., Liou, J.G., Zhang, R.Y., Lu, F.Late Mesozoic Eocene mantle replacement beneath the eastern North Chin a Craton: evidence from the Paleozoic and Cenozoic peridotite xenoliths.International Geology Review, Vol. 47, 5, May, pp. 457-472.ChinaXenoliths
DS200612-0064
2005
Griffin, W.L.Babu, E.V.S.S.K., Griffin, W.L., O'Reilly, S.Y., Pearson, N.J.Sub-continental lithospheric mantle structure of the eastern Dharwar Craton, southern India at 1.1Ga: study of garnet xenocrysts from kimberlites.Geological Society of India, Bangalore November Meeting Group Discussion on Kimberlites and Related Rocks India, Abstract p. 73-74.India, Andhra Pradesh, Dharwar CratonTectonics
DS200612-0116
2006
Griffin, W.L.Belousova, E.A., Reid, A.J., Griffin, W.L., O'Reilly, S.Y.Proterozoic rejuvenation of the Archean crust tracked by U Pb and hf isotopes in detrital zircon.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1, abstract only.AustraliaGeochronology
DS200612-0117
2006
Griffin, W.L.Belousova, E.A.,Griffin, W.L., O'Reilly, S.Y.Zircon crystal morphology, trace element signatures and Hf isotope composition as a tool for petrogenetic modelling: examples from eastern Australian granitoids.Journal of Petrology, Vol. 47, 2, pp. 329-325.AustraliaGeochronology - not specific to diamonds
DS200612-0134
2006
Griffin, W.L.Beyer, E.E., Griffin, W.L., O'Reilly, S.Y.Transformation of Archean lithospheric mantle by refertilization: evidence from exposed peridotites in the Western Gneiss region, Norway.Journal of Petrology, Vol. 47, 8, pp. 1611-1635.Europe, NorwayPeridotite, metasomatism
DS200612-0149
2006
Griffin, W.L.Bonadiman, C., Coltorti, M., Siena,F., O'Reilly, S.Y., Griffin, W.L., Pearson, N.J.Archean to Proterozoic depletion in Cape Verde lithospheric mantle.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 1, abstract only.Europe, Cape Verde IslandsGeochemistry
DS200612-0277
2006
Griffin, W.L.Cooper, S.A., Griffin, W.L., O'Reilly, S.Y.Infrared investigation of Timber Creek 01 kimberlite diamonds.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 112. abstract only.AustraliaDiamond morphology
DS200612-0500
2006
Griffin, W.L.Griffin, W.L., Pearson, N.J., Belousova, E.A., Saeed, A.Hf isotope heterogeneity in zircon 91500.... comment.Chemical Geology, Vol. 233, 3-4, Oct. 15, pp. 358-363.TechnologyGeochronology
DS200612-0501
2006
Griffin, W.L.Griffin, W.L., Rege, S., O'Reilly, S.Y., Jackson, S.E., Pearson, N.J., Zedgenizov, D., Kurat, G.Trace element patterns of diamond: toward a unified genetic model.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 218. abstract only.TechnologyDiamond genesis geochemistry
DS200612-0662
2006
Griffin, W.L.Kaminsky, F.V., Zakharchenko, O.D., Khachatryan, G.K., Griffin, W.L., Der, D.M.Diamond from the Los Coquitos area, Bolivar State, Venezuela.Canadian Mineralogist, Vol. 44, 2, April pp. 323-340.South America, VenezuelaDiamond mineralogy
DS200612-0713
2005
Griffin, W.L.Klein, E.L., Moura, C.A.V., Krmsky, R.S., Griffin, W.L.The Gurupi Belt, northern Brazil: lithostratigraphy, geochronology, and geodynamic evolution.Precambrian Research, Vol. 141, 3-4, Nov. 20, pp. 83-105.South America, BrazilGeochronology, alkaline
DS200612-1019
2006
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Imaging global chemical and thermal heterogeneity in the subcontinental lithospheric mantle with garnets and xenoliths: geophysical implications.Tectonophysics, Vol. 416, 1-4, April 5, pp. 289-309.Mantle, Australia, Russia, CanadaGeothermometry, geochemistry
DS200612-1061
2006
Griffin, W.L.Pearson, N.J., Griffin, W.L., Alard, O., O'Reilly, S.Y.The isotopic composition of magnesium in mantle olivine: records of depletion and metasomatism.Chemical Geology, Vol. 226, 3-4, pp. 115-133.Russia, Canada, Northwest Territories, AustraliaGeochronology
DS200612-1461
2006
Griffin, W.L.Van Achterbergh, E., O'Reilly, S.Y., Griffin, W.L.The origin of fertile enstatite by deep seated carbonatite metasomatism.Geochimica et Cosmochimica Acta, Vol. 70, 18, 1, p. 3, abstract only.MantleCarbonatite
DS200612-1559
2006
Griffin, W.L.Xu, Z., Griffin, W.L., Zhao, D., O'Reilly, S.Y.Modification of subcontinental lithospheric mantle in SE China.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 2. abstract only.ChinaGeochemistry
DS200612-1577
2006
Griffin, W.L.Yu, J-H., O'Reilly, S.Y., Zhang Ming, Griffin, W.L., Xu, X.Roles of melting and metasomatism in the formation of the lithospheric mantle beneath the Leizhou Peninsula, South China.Journal of Petrology, Vol. 47, 2, Feb. pp. 355-383.ChinaMetasomatism
DS200612-1603
2006
Griffin, W.L.Zheng, J., Griffin, W.L., O'Reilly, S.Y., Yang, J., Li, T., Zhang, M., Zhang, R., Liou, J.G.Mineral chemistry of peridotites from Paleozoic, Mesozoic and Cenozoic lithosphere: constraints on mantle evolution beneath eastern China.Journal of Petrology, Vol. 47, 11, pp. 2233-2256.ChinaPeridotite
DS200612-1604
2006
Griffin, W.L.Zheng, J., Griffin, W.L., O'Reilly, S.Y., Yang, J.S., Zhang, R.Y.A refractory mantle protolith in younger continental crust, east central China: age and composition of zircon in Sulu ultrahigh pressure peridotite.Geology, Vol. 34, 9, Sept. pp. 705-708.ChinaUHP, geochronology
DS200612-1605
2006
Griffin, W.L.Zheng, J., Griffin, W.L., O'Reilly, S.Y., Zhang, M., Pearson, N.Zircons in mantle xenoliths record the Triassic Yangtze North Chin a continental collision.Earth and Planetary Science Letters, in press availableChinaGeochronology, peridotite, North China Craton
DS200612-1606
2006
Griffin, W.L.Zheng, J., Griffin, W.L., O'Reilly, S.Y., Zhang, M., Pearson, N., Luo, Z.The lithospheric mantle beneath the southeastern Tian Shan area, northwest China.Contributions to Mineralogy and Petrology, Vol. 141, 4, April pp. 457-479.Asia, ChinaPetrology
DS200612-1607
2006
Griffin, W.L.Zheng, J., Griffin, W.L., O'Reilly, S.Y., Zhang, M., Pearson, N., Pan, Y.Wide spread Archean basement beneath the Yangtze Craton.Geology, Vol. 34, 6, June pp. 417-420.Asia, ChinaGeochronology
DS200712-0037
2007
Griffin, W.L.Aulbach, S., Griffin, W.L., Pearson, N.J., O'Reilly, S.Y., Doyle, B.J.Lithosphere formation in the central Slave Craton ( Canada): plume subcretion or lithosphere accretion.Contributions to Mineralogy and Petrology, Vol. 154, 4, pp. 409-427.Canada, Northwest TerritoriesAccretion
DS200712-0056
2007
Griffin, W.L.Batumike, J.M., O'Reilly, S.Y., Griffin, W.L., Belousova, E.A.U Pb and Hf isotope analyses of zircon from the Kundelungu kimberlites, D.R. Congo: implications for crustal evolution.Precambrian Research, Vol. 156, 3-4, pp. 195-225.Africa, Democratic Republic of CongoDeposit - geochronology - Kundelungu
DS200712-0057
2007
Griffin, W.L.Batumike, J.M., O'Reilly, S.Y., Griffin, W.L., Belousova, E.A.U Pb and Hf isotope analyses of zircon from the Kundelungu kimberlites, DRC: implications for crustal evolution.Precambrian Research, Vol. 156, 3-4, pp. 195-225.Africa, Democratic Republic of CongoKundelungu - geochronology
DS200712-0275
2007
Griffin, W.L.Downes, P.J., Griffin, B.J., Griffin, W.L.Mineral chemistry and zircon geochronology of xenocrysts and altered mantle and crustal xenoliths from the Aries micaceous kimberlite: constraints age..Lithos, Vol. 93, 1-2, pp. 175-198.AustraliaKimberly Craton - central composition age
DS200712-0382
2007
Griffin, W.L.Griffin, W.L., Belousoval, E.A., O'Reilly, S.Y.Crustal history and metallogenic fertility: terrane scale assessment with detrital zircons.Proceedings of Exploration 07 edited by B. Milkereit, pp. 311-315.TechnologyGeochronology - zircons
DS200712-0383
2007
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y.Cratonic lithospheric mantle: is anything subducted?Episodes, Vol. 30, 1, pp. 43-53.MantleSubduction
DS200712-0675
2007
Griffin, W.L.Malkovets, V.G., Griffin, W.L., O'Reilly, S.Y., Wood, B.J.Diamond, subcalcic garnet, and mantle metasomatism: kimberlite sampling patterns define the link.Geology, Vol. 35, 4, pp. 339-342.MantleMetasomatism
DS200712-0823
2006
Griffin, W.L.Pearson, D.J., O'Reilly, S.Y., Griffin, W.L., Alard, O., Belousova, E.Linking crustal and mantle events using in situ trace element and isotope analysis.Geochimica et Cosmochimica Acta, In press availableMantleGeochronology
DS200712-1026
2007
Griffin, W.L.Spetsius, Z.V., Griffin, W.L., O'Reilly, S.Y., Banzeruck, V.I.Trace elements in garnets of Diamondiferous xenoliths from the Nurbinskaya pipe, Yakutia.Plates, Plumes, and Paradigms, 1p. abstract p. A961.RussiaNurbinskaya
DS200712-1157
2007
Griffin, W.L.Williams, H.M., Nielsen, S.G., Renac, C., McCammon, C.A., Griffin, W.L., O'Reilly, S.Y.Fractionation of Fe and O isotopes in the mantle: implications for the origins of eclogites and the source regions of mantle plumes.Plates, Plumes, and Paradigms, 1p. abstract p. A1118.MantleSubduction
DS200712-1239
2007
Griffin, W.L.Zheng, J.P., Griffin, W.L., O'Reilly, S.Y., Yu, C.M., Zhang, H.F., Pearson, N., Zhang, M.Mechanism and timing of lithospheric modification and replacement beneath the eastern North Chin a Craton: peridotitic xenoliths from the 100 Ma Fuxin basaltsGeochimica et Cosmochimica Acta, In press, availableChinaXenoliths
DS200712-1240
2007
Griffin, W.L.Zheng, J.P., Griffin, W.L., O'Reilly, S.Y., Yu, C.M., Zhang, H.F., Pearson, N., Zhang, M.Mechanism and timing of lithospheric modification and replacement beneath the eastern North Chin a Craton: peridotitic xenoliths from the 100 Ma Fuxin basalts...Geochimica et Cosmochimica Acta, Vol. 71, 21, pp. 5303-5225.ChinaXenoliths - regional synthesis
DS200812-0011
2008
Griffin, W.L.Alard, O., Le Roux, V., Bodinier, J.L., Lorand, J.P., Griffin, W.L., O'Reilly, S.Y.How primitive is the 'primitive' mantle?Goldschmidt Conference 2008, Abstract p.A13.MantleGeochemistry, structure
DS200812-0017
2008
Griffin, W.L.Alfonso, J.C., Fernandez, M., Ranalli, G., Griffin, W.L., Connolly, J.A.D.Integrated geophysical petrological modelling of the lithosphere and sublithospheric upper mantle: methodology and applications.Journal of Geophysical Research, in press available ( 97p.)MantleModels
DS200812-0059
2008
Griffin, W.L.Aulbach, S., Creaser, R.A.,Heaman, L.M., Simonetti, S.S., Griffin, W.L., Stachel, T.Sulfides, diamonds and eclogites: their link to peridotites and Slave Craton hydrothermal evolution.Goldschmidt Conference 2008, Abstract p.A36.Canada, Northwest TerritoriesDeposit - A 154, geochronology
DS200812-0060
2008
Griffin, W.L.Aulbach, S., O'Reilly, S.Y., Griffin, W.L., Pearson, N.J.Subcontinental lithospheric mantle origin of high niobium/tantalum ratios in eclogites.Nature Geoscience, Vol. 1, 7, pp. 468-472.MantleEclogite
DS200812-0071
2008
Griffin, W.L.Babu, E.V.S.S.K., Griffin, W.L., Mukherjee, A., O'Reilly, S.Y., Belousova, E.A.Combined U Pb and Lu Hf analysis of megacrystic zircons from the Kalyandurg 4 kimberlite pipe, S. India: implications for the emplacement age and HF isotopic..9IKC.com, 3p. extended abstractIndiaGeochronology - cratonic mantle
DS200812-0089
2008
Griffin, W.L.Batumike, J.M., Griffin, W.L., Belousa, E.A., Pearson, N.J., O'Reilly, S.Y., Shee, S.R.LAM-ICPMS U-Pb dating of kimberlite perovskite: Eocene-Oligocene kimberlites from the Kundelungu Plateau D.R. Congo.Earth and Planetary Science Letters, Vol. 267, 3-4, pp.609-619.Africa, Democratic Republic of CongoGeochrononoloy - Kundelungu
DS200812-0090
2007
Griffin, W.L.Batumike, J.M., O'Reilly, S.Y., Griffin, W.L.U-Pb and Hf isotope analyses of zircon from Kundelungu kimberlites, D.R. Congo: implications for crustal evolution.Precambrian Research, Vol. 156, pp. 195-225.Africa, Democratic Republic of CongoGeochronology
DS200812-0101
2008
Griffin, W.L.Belousova, E.A., Kaminsky, F.V., Griffin, W.L.U Pb and Hf isotope and trace element composition of zircon megacrysts from the Juin a kimberlites, Brazil.Goldschmidt Conference 2008, Abstract p.A71.South America, Brazil, Mato GrossoDeposit - Pandrea
DS200812-0241
2008
Griffin, W.L.Cooper, S.A., Belousova, E.A., Griffin, W.L., Morris, B.J.Age of FS66 kimberlite beneath Murray Basin South Australia: laser ablation ICP MS dating of kimberlite zircon, perovskite and rutile.9IKC.com, 3p. extended abstractAustraliaDeposit FS66 geochronology
DS200812-0293
2008
Griffin, W.L.Donnelly, C.L., O'Reilly, S.Y., Griffin, W.L.The kimberlites and related rocks of the Kuruman kimberlite Province, Kaapvaal Craton, South Africa.9IKC.com, 3p. extended abstractAfrica, South AfricaDeposit - Kuruman - petrography
DS200812-0431
2008
Griffin, W.L.Griffin, W.L.Major transformations reveal Earth's deep secrets.Geology, Vol. 36, 1, pp.95-97.MantleGeodynamics
DS200812-0582
2008
Griffin, W.L.Kobussen, A.F., Griffin, W.L., O'Reilly, S.Y., Shee, S.R.Ghosts of lithospheres past: imaging an evolving lithospheric mantle in southern Africa.Geology, Vol. 36, 7, July pp. 515-518.Africa, South AfricaGeophysics - seismics
DS200812-0821
2008
Griffin, W.L.O'Neill, C.J., Lenardic, A., Griffin, W.L., O'Reilly, S.Y.Dynamics of cratons in an evolving mantle.Lithos, Vol. 102, 3-4, pp.12-24.MantleGeotectonics
DS200812-0829
2008
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L., Pearson, N.J., Jackson, S.E., Belousova, E.A., Alard, O., Saeed, A.Taking the pulse of the Earth: linking crustal and mantle events.Australian Journal of Earth Sciences, Vol. 55, pp. 983-995.MantleGeochronology
DS200812-0874
2008
Griffin, W.L.Pedersen, S., Andersen, T., Konnerup-Madsen, J., Griffin, W.L.Recurrent mesoproterozoic continental magmatism in south central Norway.International Journal of Earth Sciences, In press availableEurope, NorwayMagmatism
DS200812-0945
2008
Griffin, W.L.Rege, S., Griffin, W.L., Kurat, G., Jackson, S.E., Pearson, N.J., OReilly, S.Y.Trace element geochemistry of diamondite: crystallization of diamond from kimberlite carbonatite melts.Lithos, Vol. 106, 1-2, pp. 39-54.TechnologyDiamondite
DS200812-1245
2008
Griffin, W.L.Weiss, Y., Griffin, W.L., Elhlou, S., Navon, O.Comparison between LA-ICP MS and EPMA analysis of trace elements in diamonds.Chemical Geology, Vol. 252, 3-4, pp. 158-168.TechnologyDiamond inclusions
DS200812-1283
2008
Griffin, W.L.Xu, X., Griffin, W.L., O'Reilly, S.Y., Pearson, N.J., Geng, H., Zheng, J.Re-Os isotopes of sulfides in mantle xenoliths from eastern China: progressive modifications of lithospheric mantle.Lithos, Vol. 102, 3-4, pp.43-64.ChinaGeochronology
DS200812-1292
2008
Griffin, W.L.Yang, J-H, Wu, F-Y., Wilde, S.A., Belousova, E., Griffin, W.L.Mesozoic decratonization of the North Chin a block.Geology, Vol. 36, 6, June pp. 467-470.ChinaCraton
DS200812-1311
2008
Griffin, W.L.Zhang, M., O'Reilly, S.Y., Wang, K.L., Hronsky, J., Griffin, W.L.Flood basalts and metallogeny: the lithospheric mantle connection.Earth Science Reviews, Vol. 86, 1-4, pp. 145-174.MantleMetallogeny - not specific to diamonds
DS200812-1321
2008
Griffin, W.L.Zheng, J.P., Griffin, W.L., O'Reilly, S.Y., Hu, Zhang, Tang, Su, Zhang, Pearson, Wamg, Lu.Continental collision and accretion recorded in the deep lithosphere of central China.Earth and Planetary Science Letters, Vol. 269, 3-4 May 30, pp. 496-506.ChinaBasaltic diatremes, geochronology, craton, tectonics
DS200812-1322
2008
Griffin, W.L.Zheng, J.P., Sun, M., Griffin, W.L., Zhou, M.F., Zhao, G.C., Robinson, P., Tang, H.Y., Zhang, Z.H.Age and geochemistry of contrasting peridotite types in the Dabie UHP belt, eastern China: petrogenetic and geodynamic implications.Chemical Geology, Vol. 247, pp. 282-304.ChinaUHP
DS200912-0007
2009
Griffin, W.L.Araujo, D.P., Griffin, W.L., O'Reilly, S.Y.Mantle melts, metasomatism and diamond formation: insights from melt inclusions in xenoliths from Diavik, Slave Craton.Lithos, In press available, 34p.Canada, Northwest TerritoriesDeposit - Diavik
DS200912-0008
2009
Griffin, W.L.Araujo, D.P., Griffin, W.L., O'Reilly, S.Y., Grant, K.J., Ireland, T., Van Achterbergh, E.Micro inclusions in monocrystalline octahedral diamonds and coated diamonds from Diavik, Slave Craton: clues to diamond genesis.Lithos, In press available 38p.Canada, Northwest TerritoriesDeposit - Diavik
DS200912-0018
2009
Griffin, W.L.Aulbach, S., Creaser, R.A., Pearson, N.J., Simonetti, S.S., Heaman, L.M., Griffin, W.L., Stachel, T.Sulfide and whole rock Re-Os systematics of eclogite and pyroxenite xenoliths from the Slave Craton, Canada.Earth and Planetary Science Letters, in press available,Canada, Northwest TerritoriesDeposit - Diavik
DS200912-0037
2009
Griffin, W.L.Batumike, J.M., Griffin, W.L., O'Reilly, S.Y.Lithospheric mantle structure and the diamond potential of kimberlites in southern D.R. Congo.Lithos, In press available 11p.Africa, Democratic Republic of CongoMetasomatism
DS200912-0038
2009
Griffin, W.L.Batumike, J.M., Griffin, W.L., O'Reilly, S.Y., Belousova, E.A., Palitschek, M.Crustal evolution in the central Congo -Kasai Craton, Luebo, D.R. Congo: insights from zircon U Pb ages, Hf isotope and trace element data.Precambrian Research, Vol. 170, 1-2, pp. 107-115.Africa, Democratic Republic of CongoGeochronology
DS200912-0041
2009
Griffin, W.L.Begg, G., Belousova, E., Griffin, W.L., O'Reilly, S.Y., Natapov, L.Continental versus crustal growth: resolving the paradox.Goldschmidt Conference 2009, p. A103 Abstract.MantleArchean - Boundary
DS200912-0042
2009
Griffin, W.L.Begg, G.C., Griffin, W.L., Natapov, O'Reilly, Grand, O'Neill, Hronsky, Poudjom Djomeni, Swain, Deen, BowdenThe lithospheric architecture of Africa: seismic tomography, mantle petrology, and tectonic evolution.Geosphere, Vol. 5, pp. 23-50.AfricaGeophysics - seismic, tectonics
DS200912-0048
2009
Griffin, W.L.Belousova, E., Kostitsyn, Y.A., Griffin, W.L., O'Reilly, S.Y.Testing models for continental crustal growth: a TerraneChron approach.Goldschmidt Conference 2009, p. A107 Abstract.MantleDatabase
DS200912-0049
2009
Griffin, W.L.Belousova, E.A., Reid, A.J., Griffin, W.L., O'Reilly, S.Y.Rejuvenation vs recycling of Archean crust in the Gawler Craton, south Australia: evidence from U Pb and Hf isotopes in detrital zircon.Lithos, In press - available 52p.AustraliaGeochronology
DS200912-0266
2009
Griffin, W.L.Griffin, W.L., Begg, G., O'Reilly, S.Y., Afonso, J.C.Paleo-Archean generation of the continental lithosphere.Goldschmidt Conference 2009, p. A466 Abstract.MantleKimberlite xenoliths
DS200912-0267
2009
Griffin, W.L.Griffin, W.L., Kobussen, A.F., Babu, E.V.S.S.K., O'Reilly, S.Y., Norris, R., Sengupta, P.A translithospheric suture in the vanished 1 Ga lithospheric root of South India: evidence from contrasting lithospheric sections in the Dharwar Craton.Lithos, In press available, 31p.IndiaKimberlites - xenoliths
DS200912-0268
2009
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y., Afonso, J.C., Begg, G.C.The composition and evolution of lithospheric mantle: a re-evaluation and its tectonic implications.Journal of Petrology, Vol. 50,no. 7,. pp. 1185-1204.MantleTectonics
DS200912-0356
2009
Griffin, W.L.Kaminsky, F.V., Khachatryan, G.K., Andreazza, P., Araujo, D., Griffin, W.L.Super deep diamonds from kimberlites in the Juin a area, Mato Grosso State, Brazil.Lithos, Vol. 1125, pp. 833-842.South America, Brazil, Mato GrossoDiamond inclusions
DS200912-0357
2009
Griffin, W.L.Kaminsky, F.V., Sablukov, S.M., Belousova, E.A., Andreazza, P., Tremblay, M., Griffin, W.L.Kimberlite sources of super deep diamonds in the Juin a area, Mato Grosso State, Brazil.Lithos, In press available,South America, Brazil, Mato GrossoKimberlite genesis
DS200912-0390
2009
Griffin, W.L.Kobussen, A.F., Griffin, W.L., O'Reilly, S.Y.Cretaceous, thermo-chemical modification of the Kaapvaal cratonic lithosphere, South Africa.Lithos, In press - available 28p.Africa, South AfricaGeothermometry
DS200912-0429
2009
Griffin, W.L.Le Roux, V., Bodinier, J-L., Allard, O., O'Reilly, S.Y., Griffin, W.L.Isotopic decoupling during porous melt flow: a case study in the Lherz peridotite.Earth and Planetary Science Letters, Vol. 279, 1-2, pp.76-85.Europe, FranceGeochronology
DS200912-0470
2009
Griffin, W.L.Malkovets, V.G., Belousova, E.A., Griffin, W.L., Buzlukova, L.V., Shatsky, V.S., O'Reilly, S.Y., Pokhilenko, N.P.U/Pb dating of zircons from the lower crustal xenoliths from Siberian kimberlites.Goldschmidt Conference 2009, p. A823 Abstract.Russia, SiberiaDeposit - Udachnaya
DS200912-0552
2009
Griffin, W.L.O'Reilly, S.Y., Zhang, M., Griffin, W.L.Ultradeep continental roots and their stranded oceanic remnants: a solution to the geochemical crustal reservoir problem?Goldschmidt Conference 2009, p. A960 Abstract.MantleTomography - geophysics - seismics
DS200912-0553
2009
Griffin, W.L.O'Reilly, S.Y., Zhang, M., Griffin, W.L., Begg, G., Hronsky, J.Ultradeep continental roots and their oceanic remnants: a solution to the geochemical 'mantle reservoir' problem?Lithos, In press available 41p.MantleGeochemistry
DS200912-0810
2009
Griffin, W.L.Weiss, Y., Kessel, R., Griffin, W.L., Kiflawi, I., Klein-BenDavid, O., Bell, D.R., Harris, J.W., Navon, O.A new model for the evolution of diamond forming fluids: evidence from Micro inclusion bearing diamonds from Kankan, Guinea.Lithos, In press - available 43p.Africa, GuineaDeposit - Kankan
DS200912-0849
2009
Griffin, W.L.Zedgenizov, D.A., Ragozin, A.L., Shjatsky, V.S., Araujo, D., Griffin, W.L., Kagi, H.Mg and Fe rich carbonate silicate high density fluids in cuboid diamonds from the Internationalnaya kimberlite pipe. Yakutia.Lithos, In press availableRussia, YakutiaDeposit - International
DS200912-0859
2009
Griffin, W.L.Zheng, J., Griffin, W.L., O'Reilly, S.Y., Liu, G.L., Pearson, N., Zhang, W., Yu, C.M., Su, Tang, ZhaoNeoarchean ( 2.7-2.8 Ga) accretion beneath the North Chin a Craton: U Pn age.trace elemens and hf isotopes of zircons in Diamondiferous kimberlites.Lithos, Vol. 112, 3-4, pp. 188-202.ChinaGeochronology
DS200912-0860
2009
Griffin, W.L.Zheng, J.P., Griffin, W.L., O'Reilly, S.Y., Sun, M., Zheng, S., Pearson, N., Gao, Yu, Su, Tang, Liu, WuAge and composition of granulite and pyroxenite xenoliths in Hannuoba basalts reflect Paleogene underplating beneath the North Chin a craton.Chemical Geology, Vol. 264, 1-4, pp. 266-280.ChinaXenoliths
DS200912-0861
2009
Griffin, W.L.Zheng, J.P., Griffin, W.L., O'Reilly, S.Y., Zhao, J.H., Wu, Liu, Pearson, Zhang, Ma, Zhang, Yu, Su, TangNeoarchean ( 2.7-2.8 Ga) accretion beneath the North Chin a Craton: U Pb age, trace elements and Hf isotopes of zircons in Diamondiferous kimberlites.Lithos, Vol. 117, pp. 188-202.ChinaGeochronology
DS201012-0003
2010
Griffin, W.L.Afonso, J.C., Ranalli, G., Fernandez, M., Griffin, W.L., O'Reilly, S.Y., Faul, U.On the VpVs-Mg# correlation in mantle peridotites: implications for the identification of thermal and compositional anomalies in the upper mantle.Earth and Planetary Science Letters, Vol. 289, 3-4, pp. 606-618.MantleChemistry
DS201012-0048
2010
Griffin, W.L.Belousova, E.A., Kostitsyn, Y.A., Griffin, W.L., Begg, G.C., O'Reilly, S.Y.The growth of the continental crust: constraints from zircon Hf isotope data.Lithos, Vol. 119, pp. 457-466.MantleGeochronology
DS201012-0163
2010
Griffin, W.L.Donnelly, C.L., Griffin, W.L., O'Reilly, S.Y.,Pearson, N.J., Shee, S.R.The kimberlites and related rocks of the Kuruman kimberlite Province, Kaapvaal Craton, South Africa.Contributions to Mineralogy and Petrology, in press available 21p.Africa, South AfricaGeochemistry - trace elements
DS201012-0251
2009
Griffin, W.L.Griffin, W.L., Kobussen, A.F., Babu, E.V.S.S.K., O'Reilly, S.Y., Norris, R., Sengupta, P.A translithospheric suture in the vanished 1 Ga lithospheric root of South India: evidence from contrasting lithosphere sections in the Dharwar craton.Lithos, Vol. 112 S pp. 1109-1119.IndiaKimberlites and garnet geotherms
DS201012-0341
2010
Griffin, W.L.Kaminsky, F.V., Sablukov, S.M., Belousova, E.A., Andreazza, P., Tremblay, M., Griffin, W.L.Kimberlitic sources of super deep diamonds in the Juin a area, Mato Grosso State, Bahia.Lithos, Vol. 114, pp. 16-29.South America, Brazil, Mato GrossoChapadao, Padrea
DS201012-0361
2010
Griffin, W.L.Kiflawi, I., Weiss, Y.,Griffin, W.L., Navon, O.EPMA, FTIR and LA ICP MS determination of the composition of fluid microinclsuions in diamonds.Goldschmidt 2010 abstracts, abstractTechnologyDiamond inclusions
DS201012-0473
2010
Griffin, W.L.Marchesi, C., Griffin, W.L., Garrido, C.J., Bodinier, J-L., O'Reilly, S.Y., Pearson, N.J.Persistence of mantle lithospheric Re-Os signature during asthenospherization of the subcontinental lithospheric mantle: insights in situ sulphides....Contributions to Mineralogy and Petrology, Vol. 159, 3, pp. 315-330.Europe, SpainRonda peridotite
DS201012-0530
2010
Griffin, W.L.Navon, O., Weiss, Y., Griffin, W.L.Sources of diamond forming fluids.Goldschmidt 2010 abstracts, abstractTechnologyDiamond genesis
DS201012-0556
2010
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.The continental lithosphere-asthenosphere boundary: can we sample it?Lithos, Vol. 120, 1-2, Nov. pp. 1-13.MantleBoundary
DS201012-0617
2010
Griffin, W.L.Rege, S., Griffin, W.L., Pearson, A.J., Araujo, D., Zedgenizov, D., O'Reilly, S.Y.Trace element patterns of fibrous and monocrystalline diamonds: insights into mantle fluids.Lithos, Vol. 118, pp. 313-337.TechnologyDiamond genesis, morphology
DS201012-0698
2010
Griffin, W.L.Shiryae, A.A., Griffin, W.L., Tomshin, M.D., Okrugin, A.Natural silicon carbide from kimberlites: polytypes, trace elements, inclusions and speculations on its origin.International Mineralogical Association meeting August Budapest, abstract p. 181.TechnologyMoissanite
DS201012-0842
2010
Griffin, W.L.Weiss, Y., Navon, O., Griffin, W.L.Fibrous diamonds.Goldschmidt 2010 abstracts, abstractTechnologyDiamond morphology
DS201012-0894
2010
Griffin, W.L.Zhong, J.P., Griffin, W.L., Sun, M., O'Reilly, S.Y., Zhang, H.F., Zhou, J., Xiao, L., Tang, H.Y., Zhang, Z.Tectonic affinity of the west Qingling terrane ( central Chin a): North Chin a or Yangtze?Tectonics, Vol. 29, 2, TC2009ChinaTectonics
DS201112-0283
2011
Griffin, W.L.Donnelly, C.L., Griffin, W.L., O'Reilly, S.Y.,Pearson, N.J., Shee, S.R.The kimberlites and related rocks of the Kuruman kimberlite province, Kaapvaal craton, South Africa.Contributions to Mineralogy and Petrology, Vol. 161, 3, pp. 351-371.Africa, South AfricaDeposit -
DS201112-0386
2011
Griffin, W.L.Greau, Y., Huang, J-X., Griffin, W.L., Renac, C., Alard, O., O'Reilly, S.Y.Type 1 eclogite from Roberts Victor kimberlites: products of extensive mantle metasomatism.Geochimica et Cosmochimica Acta, Vol. 75, 22, pp. 6927-2954.Africa, South AfricaDeposit - Roberts Victor
DS201112-0387
2011
Griffin, W.L.Griffin, W.L., Begg, G., O'Reilly, S.Y., Pearson, N.J.Ore deposits and the SCLM.Goldschmidt Conference 2011, abstract p.946.MantleKimberlites - low degree melting prev. metasomatised
DS201112-0388
2011
Griffin, W.L.Griffin, W.L., Begg, G.C., Dunn, D., O'Reilly, S.Y., Natapov, L.M., Karlstrom, K.Archean lithospheric mantle beneath Arkansas: continental growth by microcontinent accretion.Geological Society of America Bulletin, Vol. 123, 9-10, pp. 1763-1775.United States, ArkansasPrairie Creek lamproites
DS201112-0389
2011
Griffin, W.L.Griffin, W.L., Begg, G.C., Dunn, D., O'Reilly, S.Y., Natapov, L.M., Karlstrom, K.Archean lithospheric mantle beneath Arkansas: continental growth by microcontinent accretion.Geological Society of America Bulletin, Vol. 123, 9/10 pp. 1763-1775.United States, ArkansasPrairie Creek lamproites
DS201112-0454
2011
Griffin, W.L.Howell, D., Griffin, W.L., O'Reilly, S.Y., O'Neill, C., Pearson, N., Piazolo, Stachel, Stern, NasdalaMixed habit diamonds: evidence of a specific mantle fluid chemistry?Goldschmidt Conference 2011, abstract p.1051.TechnologyDiamond morphology, growth
DS201112-0518
2011
Griffin, W.L.Kiflawi, I., Weiss, Y., Griffin, W.L., Navon, O.Fluid inclusions in octahedral diamonds.Goldschmidt Conference 2011, abstract p.1182.Africa, South Africa, GuineaFinsch, Kankan
DS201112-0710
2011
Griffin, W.L.Murgulov, V., Griffin, W.L., O'Reilly, S.Y.Lithospheric mantle evolution beneath northeast Australia.Lithos, Vol. 125, pp. 405-422.AustraliaGeochronology,lherzolites, crust mantle linkage
DS201112-0728
2011
Griffin, W.L.Navon, O., Griffin, W.L., Weiss, Y.Table vs bench trace elements in fibrous diamonds.Goldschmidt Conference 2011, abstract p.1528.TechnologyDiamond morphology - high density fluids
DS201112-0761
2010
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Rates of magma ascent: constraints from mantle derived xenoliths.In: Dosseto, A., Turner, S.P., Van Orman, J.A. eds. Timescales of magmatic processes: from core to atmosph., Blackwell Publ. Chapter 6, p. 116-MantleMagmatism
DS201112-0945
2011
Griffin, W.L.Shatsky, V.S., Malkovets, V.G., Buzlukova, L., Griffin, W.L., Belousova, E.A., O'Reilly, S.Y.Deep crust of the Siberian craton evidence from xenolith.Goldschmidt Conference 2011, abstract p.1850.RussiaUdachnaya, Leningradskaya, Yubileynaya
DS201112-0954
2011
Griffin, W.L.Shiryaev, A.A., Griffin, W.L., Stoyanov, E.Moissanite (SiC) from kimberlites: polytypes, trace elements, inclusions and speculations on origin.Lithos, Vol. 122, pp. 152-164.Russia, YakutiaDeposit - Mir, Aikhal, Udachnaya
DS201112-0991
2011
Griffin, W.L.Spetsius, Z.V., Belousova, E.A., Griffin, W.L., O'Reilly, S.Y., Ivanov, A.S.Zircon from kimberlites of the Nyurbinskaya pipe as indicator of kimberlite emplacement and lithosphere evolution.Goldschmidt Conference 2011, abstract p.1922.RussiaNakynsky
DS201112-1064
2011
Griffin, W.L.Urgulov, V., Griffin, W.L., O'Reilly, S.Y.Lithospheric mantle evolution beneath northeast Australia.Lithos, Vol. 125, pp. 405-422.AustraliaMantle lherzolite xenoliths, linkage
DS201112-1101
2011
Griffin, W.L.Wang, K-L., O'Reilly, S.Y., Griffin, W.L., Pearson, N.J., Kovach, V., Yarmolyuk, V.Primordial ages of lithospheric mantle vs ancient relicts in the asthenospheric mantle: in situ Os perspective.Goldschmidt Conference 2011, abstract p.2121.Russia, MongoliaConvection
DS201112-1109
2011
Griffin, W.L.Weiss, Y., Griffin, W.L., Bell, D.R., Navon, O.High Mg carbonatitic HDFs, kimberlites and SCLM.Goldschmidt Conference 2011, abstract p.2143.RussiaFibrous diamonds
DS201201-0851
2011
Griffin, W.L.Kahoui, M., Kemainsky, F.V., Griffin, W.L., Belousova, E., Mahdjoub, Y., Chabane, M.Detrital pyrope garnets from the El Kseibat area, Algeria: a glimpse into the lithospheric mantle beneath the north-eastern edge of the West African Craton.Journal of African Earth Sciences, In press available, 46p.Africa, AlgeriaGeochemistry - El Kseibat
DS201212-0010
2012
Griffin, W.L.Alifirova, T.A., Pokhilenko, L.N., Malkovets, V.G., Griffin, W.L.Petrological inferences for the role of exsolution in upper mantle: evidence from the Yakutian kimberlite xenoliths.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractRussia, YakutiaPetrology
DS201212-0068
2012
Griffin, W.L.Beyer, E.E., Brueckner, H.K., Griffin, W.L., O'Reilly, S.Y.Laurentian provenance of Archean mantle fragments in the Proterozoic Baltic crust of the Norwegian Caledonides.Journal of Petrology, Vol. 53, 7, pp. 1357-1383.Europe, NorwayGeochronology
DS201212-0167
2012
Griffin, W.L.Donnelly, C.L., Griffin, W.L., Yang, J-H., O'Reilly, Z.Y., li Li, Q., Pearson, N.J., Li, X-H.In situ U Pb dating and Sr Nd isotopic analysis of perovskite: constraints on the age and petrogenesis of the Kuruman kimberlite province, Kaapvaal Craton, South Africa.Journal of Petrology, Vol. 53, 12, pp. 2407-2522.Africa, South AfricaDeposit - Kuruman
DS201212-0242
2012
Griffin, W.L.Gibsher, A.A., Malkovets, V.G., Griffin, W.L., O'Reilly, S.Y.Petrogenesis of composite xenoliths from alkaline basalts ( West Sangilen) Russia10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussiaAlkalic
DS201212-0310
2012
Griffin, W.L.Howell, D., O'Neill, C.J., Grant, K.J., Griffin, W.L., O'Reilly, S.Y., Pearson, N.J., Stern, R.A., Stachel, T.Platelet development in cuboid diamonds: insights from micro-FTIR mapping.Contributions to Mineralogy and Petrology, Vol. 164, 6, pp. 1011-1025.TechnologyDiamond morphology
DS201212-0311
2012
Griffin, W.L.Howell, D., Piazolo, S., Dobson, D.P., Wood, I.G., Jones, A.P., Watte, N., Frost, D.J., Fisher, D., Griffin, W.L.Quantitative characterization of plastic deformation of single diamond crystals: a high pressure high temperature (HPHT) experimental deformation study combines with electron backscatter diffraction.Diamond and Related Materials, Vol. 30, pp. 20-30.TechnologyDiamond morphology
DS201212-0313
2012
Griffin, W.L.Huang, J.-X., Griffin, W.L., Greau, Y., O'Reilly, S.Y.Seeking the primary compositions of mantle xenoliths: isotopic and elemental consequences of sequential leaching treatments on an eclogite suite.Chemical Geology, in press availableAfrica, South AfricaDeposit - Roberts Victor
DS201212-0314
2012
Griffin, W.L.Huang, J-X., Greau, Y., Griffin, W.L., O'Reilly, S.Y., Pearson, N.J.Multi-stage origin of Roberts Victor eclogites: progressive metasomatism and its isotopic effects.Lithos, in press availableAfrica, South AfricaDeposit - Roberts Victor
DS201212-0346
2012
Griffin, W.L.Kahoui, M., Kaminsky, F.V., Griffin, W.L., Belousova, E., Mahdjoub, Y., Chabane, M.Detrital pyrope garnets from the El Kseibat area, Algeria: a glimpse into lithospheric mantle beneath the north eastern edge of the west African Craton.Journal of African Earth Sciences, Vol. 63, Feb. pp. 1-11.AfricaEglab shield
DS201212-0438
2012
Griffin, W.L.Malkovets, V.G., Griffin, W.L., Pearson, N.J., Rezvukhin, D.I., Oreilly, S.Y., Pokhilenko, N.P., Garanin, V.K., Spetsius, Z.V., Litasov, K.D.Late metasomatic addition of garnet to the SCLM: Os-itope evidence.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractMantleMetasomatism
DS201212-0439
2012
Griffin, W.L.Malkovets, V.G., Griffin, W.L., Pokhilenko, N.P., O'Reilly, S.Y., Dak, A.I., Tolstov, A.V., Serov, I.V., Bazhan, I.S., Kuzmin, D.V.Lithosphere mantle structure beneath the Nakyn kimberlite field, Yakutia.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, YakutiaDeposit - Nakyn
DS201212-0505
2012
Griffin, W.L.Murgulov, V., Griffin, W.L., O'Reilly, S.Y.Temporal correlation of magmatic tectonic events in the lower and upper crust in north east Australia.International Journal of Earth Sciences, Vol. 101, 5, pp. 1091-1109.AustraliaMagmatism
DS201212-0511
2012
Griffin, W.L.Navon, O., Griffin, W.L., Weiss, Y.Tables vs "benchs": trace elements in fibrous diamonds,10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractGlobalDiamonds - fibrous
DS201212-0583
2012
Griffin, W.L.Rezvukhin, D.I., Malkovets, V.G., Gibsher, A.A., Kuzmin, D.V., Griffin, W.L., Pokhilenko, N.P., O'Reilly, S.Y.Mineral inclusions in pyropes from some kimberlite pipes of Yakutia.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, YakutiaDeposit - Internationskaya
DS201212-0604
2012
Griffin, W.L.Rubanova, E.V., Griffin, W.L., Plazoloa, S., O'Reilley, S.Y., Stachel, T., Sten, R., Birniec, A.C.Geochemistry and microstructure of diamondites.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractTechnologyDiamondites
DS201212-0695
2012
Griffin, W.L.Spetsius, Z.V., Griffin, W.L., Ivanov, A.S.Inclusions and internal structure of diamonds: a key to their genetic growth.emc2012 @ uni-frankfurt.de, 1p. AbstractRussiaDeposit - Udachnaya, Nurbinskaya
DS201212-0767
2012
Griffin, W.L.Weiss, Y., Griffin, W.L., Bell, D.R., Navon, O.High Mg carbonatitic HDFS, kimberlites and the SCLM.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractMantleCarbonatite
DS201212-0768
2012
Griffin, W.L.Weiss, Y., Kiflawi, I., Griffin, W.L.,Navon, O.Fluid Micro inclusions in monocrystalline diamonds.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussiaDeposit - Yakutia
DS201212-0826
2012
Griffin, W.L.Zheng, J.P., Griffin, W.L., Ma, Q., O'Reilly, S.Y., Xiong, Q., Tang, H.Y., Zhao, J.H., Yu, C.M., Su, Y.P.Accretion and reworking beneath the North Chin a craton.Lithos, Vol. 149, pp. 61-78.ChinaAccretion
DS201312-0039
2013
Griffin, W.L.Aulbach, S., Griffin, W.L., Pearson, N.J., O'Reilly, S.Y.Nature and timing of metasomatism in the stratified mantle lithosphere beneath the Central Slave Craton ( Canada).Chemical Geology, Vol. 352, pp. 153-169.Canada, Northwest TerritoriesCraton
DS201312-0320
2013
Griffin, W.L.Gonzalez-Jimienez, J.M., Marchesi, C., Griffin, W.L., Gutierrez-Narbona, R., Lorand, J-P., O'Reilly, S.Y., Garrido, C.J., Gervilla, F., Pearson, N.J., Hidas, K.Transfer of Os isotopic signatures from peridotite to chromitite in the subcontinental mantle: insights from in situ analysis of platinum-group and base metal minerals (Ojen peridotite massif, southern Spain.Lithos, Vol. 164-167, pp. 74-85.Europe, SpainChromitite
DS201312-0322
2013
Griffin, W.L.Gonzalez-Jimienez, J.M., Griffin, W.L., Gervilla, F., Proenza, J.A., O'Reilly, S.Y., Pearson, N.J.Chromitites in ophiolites: how, where, when, why? Part 1. A review of new ideas on the origin and significance of platinum-group minerals.Lithos, Vol. 189, pp. 127-139.MantleGeodynamics
DS201312-0333
2013
Griffin, W.L.Greau, Y., Alard, O., Griffin, W.L., Huang, J-X., O'Reilly, S.Y.Sulfides and chalcophile elements in Roberts Victor eclogites: unravelling a sulfide rich metasomatic event.Chemical Geology, Vol. 354, pp. 73-92.Africa, South AfricaDeposit - Roberts Victor
DS201312-0335
2013
Griffin, W.L.Griffin, W.L., Begg, G.C., O'Reilly, S.Y.Continental root control on the genesis of magmatic ore deposits.Nature Geoscience, 6p. On line Oct 13TechnologyMagmatism
DS201312-0336
2013
Griffin, W.L.Griffin, W.L., Belousova, E.A., O'Neill, C., O'Reilly, S.Y., Malkovets, V., Pearson, N.J., Spetsius, S., Wilde, S.A.The world turns over: Hadean-Archean crust mantle evolution.Lithos, Vol. 189, pp. 2-15.MantleCrust- mantle review
DS201312-0337
2013
Griffin, W.L.Griffin, W.L., Yang, J.S., Robinson, P., Howell, D., Shi, R., O'Reilly, S.Y., Pearson, D.J.Diamonds and super reducing UHP assemblages in ophiolitic mantle, Tibet: where are the eclogites?X International Eclogite Conference, 1p. abstractAsia, TibetDiamond genesis
DS201312-0403
2013
Griffin, W.L.Howell, D., Griffin, W.L., Pearson, N.J., Powell, W., Wieland, P., O'Reilly, S.Y.Trace element partitioning in mixed habit diamonds.Chemical Geology, Vol. 355, pp. 134-143.TechnologyCrystallography
DS201312-0404
2013
Griffin, W.L.Howell, D., Stern, R.A., Griffin, W.L., Southworth, R., Mikhail, S., Stachel, T., Verchovsky, A.B., O'Reilly, S.Y., Pearson, N.J.New thermodynamic models and calculated phase equilibration temperatures in NCFMAS for basic and ultrabasic compositions through the transition zone into the uppermost lower mantle.Goldschmidt 2013, AbstractTechnologyCrystallography
DS201312-0406
2015
Griffin, W.L.Howell, D., Stern, R.A., Griffin, W.L., Southworth, R., Mikhail, S., Stachel, T.Nitrogen isotope systematics and origins of mixed-habit diamonds.Geochimica et Cosmochimica Acta, Vol. 157, pp. 1-12.Africa, South AfricaDeposit - Roberst Victor
DS201312-0407
2013
Griffin, W.L.Huang, J-X., Griffin, W.L., Greau, Y., Pearson, N.J., O'Reilly, S.Y.Unmasking enigmatic xenolithic eclogites: progressive metasomatism on a key Roberts Victor sample.Goldschmidt 2013, AbstractAfricaKamafugite
DS201312-0454
2012
Griffin, W.L.Kaminsky, F.V., Kahoui, M.,Mahdjoub, Y., Belousova, E., Griffin, W.L.,O'Reilly, S.Y.Pyrope garnets from the Eglab Shield, Algeria: look inside the Earth's mantle in the West African Craton and suggestions about primary sources of diamond and indicator minerals.Vladykin, N.V. ed. Deep seated magmatism, its sources and plumes, Russian Academy of Sciences, pp. 73-103.Africa, AlgeriaMineralogy
DS201312-0461
2014
Griffin, W.L.Karmalkar, N.R., Duraiswami, R.A., Jonnalagadda, M.K., Griffin, W.L.Mid-Cretaceous lamproite from the Kutch region, Gujarat, India: genesis and tectonic implications.Gondwana Research, Vol. 26, 3-4, pp. 942-956.IndiaLamproite
DS201312-0613
2013
Griffin, W.L.Mondal, S.K., Maier, W-G., Griffin, W.L.Ore deposits and the role of the lithospheric mantle.Lithos, One page introduction to forthcoming issue…. Does not appear to include diamonds.MantleMetasomatism
DS201312-0667
2013
Griffin, W.L.O'reilly, S., Griffin, W.L., Begg, G.C., Pearson, D.G., Hronsky, J.M.A.Archean lithospheric mantle: the fount of all ores?Goldschmidt 2013, AbstractMantleMagmatism
DS201312-0668
2013
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Chapter 12 Mantle Metasomatism.Harlow and Austrheim eds. Metasomatism and the chemical transformation of rock. Lecture notes in Earth Sciences, in press availableMantleMetasomatism
DS201312-0669
2013
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L.Moho vs crust mantle boundary: evolution of an idea.Tectonophysics, Vol. 609, pp. 535-546.MantleBoundary
DS201312-0729
2013
Griffin, W.L.Ragozin, A.L., Shatsky, V.S., Zedgenizov, D.A., Griffin, W.L.Growth medium and carbon source of unusual rounded diamonds from alluvial placers of the north-east of Siberian platform.Goldschmidt 2013, AbstractRussia, SiberiaPlacers, alluvials
DS201312-0810
2013
Griffin, W.L.Shi, R.D., Griffin, W.L., O'Reilly, S.Y., Zhang, X.R., Huang, Q.S., Gong, X.H., Ding, L.Geodynamic constraints on the recycling of ancient SCLM and genesis of Tibetan Diamondiferous ophiolites.Goldschmidt 2013, 1p. AbstractAsia, TibetOphiolites
DS201312-0811
2013
Griffin, W.L.Shi, R.D., Griffin, W.L., O'Reilly, S.Y., Zhang, X.R., Huang, Q.S., Gong, X.H., Ding, L.Recycling of ancient SCLM and genesis of Tibetan Diamondiferous ophiolites.Goldschmidt 2013, AbstractAsia, TibetOphiolites
DS201312-0951
2013
Griffin, W.L.Wang, K-L., Chien, Y-H., Kuzmin, M.I., O'Reilly, S.Y., Griffin, W.L.Geochemical fingerprints in Siberian mantle xenoliths reveal progressive erosion of an Archean lithospheric root.Goldschmidt 2013, 1p. AbstractRussiaVitim Plateau
DS201312-0953
2013
Griffin, W.L.Wang, L-J., Griffin, W.L., Yu, J-H., O'Reilly, S.Y.U Pb and Lu Hf isotopes in detrital zircon from Neoproterozoic sedimentary rocks in the northern Yangtze block: implications for Precambrian crust evolution.Gondwana Research, Vol. 23, 4, pp. 1261-1272.ChinaGeochronology
DS201312-0961
2013
Griffin, W.L.Weiss, Y., Griffin, W.L., Navon, O.Diamond forming fluids in fibrous diamonds: the trace element perspective.Earth and Planetary Science Letters, Vol. 376, pp. 110-125.Canada, Northwest Territories, Africa, Guinea, South AfricaHDFs
DS201312-0962
2013
Griffin, W.L.Weiss, Y., Griffin, W.L., Navon, O.Diamond - forming fluids: the trace element perspective.Goldschmidt 2013, 1p. AbstractMantleHDF, planed, ribbed
DS201312-1007
2013
Griffin, W.L.Zedgenizov, D.A., Ragozin, A.L., Shatsky, V.S., Griffin, W.L.Parental growth media of Siberian diamonds - relation to kimberlites.Goldschmidt 2013, 1p. AbstractRussiaDiamond morphology
DS201412-0313
1999
Griffin, W.L.Griffin, W.L., et al.The composition and origin of sub-continental lithospheric mantle.Geochemical Society Special Publication No. 6, Mantle Petrology, No. 6, pp.MantleGeochemistry
DS201412-0314
2014
Griffin, W.L.Griffin, W.L., Batumike, J.M., Greau, Y., Pearson, N.J., Shee, S.R., O'Reilly, S.Y.Emplacement ages and sources of kimberlites and related rocks in southern Africa: U-Pb ages and Sr-Nd isotopes of groundmass perovskite.Contributions to Mineralogy and Petrology, Vol. 167, pp. 1032-37.Africa, southern AfricaDeposit - geochronology
DS201412-0315
2014
Griffin, W.L.Griffin, W.L., Pearson, N.J., Andersen, T., Jackson, S.E., O'Reilly, S.Y., Zhang, M.Sources of cratonic metasomatic fluids: In-situ LA-MC-ICPMS analysis of Sr, Nd and Pb isotopes in Lima from the Jagersfontein kimberlite.American Journal of Science, Vol. 314, pp. 435-461.Africa, South AfricaDeposit - Jagersfontein
DS201412-0380
2014
Griffin, W.L.Huang, J-X., Griffin, W.L., Greau, Y., Pearson, N.J., O'Reilly, S.Y., Cliff, J., Martin, L.Unmasking xenolithic eclogites: progressive metasomatism of a key Roberts Victor sample.Chemical Geology, Vol. 364, pp. 55-65.Africa, South AfricaDeposit - Roberts Victor
DS201412-0381
2014
Griffin, W.L.Huang, J-X., Li, P., Griffin, W.L., Xia, Q-K, Greau, Y., Pearson, N.J., O'Reilly, S.Y.Water contents of Roberts Victor xenolithic eclogites: primary and metasomatic controls.Contributions to Mineralogy and Petrology, Vol. 168, pp. 1092-1095Africa, South AfricaDeposit - Roberts Victor
DS201412-0438
2014
Griffin, W.L.Kamenetsky, V.S., Belousova, E.A., Giuliani, A., Kamenetsky, M.B., Goemann, K., Griffin, W.L.Chemical abrasion of zircon and ilmenite megacrysts in the Monastery kimberlite: implications for the composition of kimberlite melts.Chemical Geology, Vol. 383, pp. 76-85.Africa, South AfricaDeposit - Monastery
DS201412-0444
2014
Griffin, W.L.Karmalkar, N.R., Duraiswami, R.A., Jonnalagadda, M.K., Griffin, W.L.Mid-Cretaceous lamproite from the Kutch region, Gujarat, NW India: genesis and tectonic implications.Gondwana Research, Vol. 26, 3-4, Nov. pp. 942-956.IndiaLamproite
DS201412-0648
2013
Griffin, W.L.O'Neill, C., Debaille, V., Griffin, W.L.Deep earth recycling in the Hadean and constraints on surface tectonics.American Journal of Science, Vol. 313, Nov. pp. 912-932.MantleTectonics
DS201502-0063
2014
Griffin, W.L.Huang, J-X., Li, P., Griffin, W.L., Xia, Q-K, Greau, Y., Pearson, N.J., O'Reilly, S.Y.Water contents of Roberts Victor xenolithic eclogites: primary and metasomatic controls.Contributions to Mineralogy and Petrology, Vol. 168, pp. 1092-1105.Africa, South AfricaDeposit - Roberts Victor
DS201503-0166
2015
Griffin, W.L.Pasava, J., Malec, J., Griffin, W.L., Gonzalez-Jiminez, J.M.Re-Os isotopic constraints on the source of platinum-group minerals (PGMs) from the Vestrev pyrope rich garnet placer deposit, Bohemian Massif.Ore Geology Reviews, Vol. 68, pp. 117-1326EuropeGarnet mineralogy
DS201503-0181
2015
Griffin, W.L.Van Kranendonk, M.J., Smithies, R.H., Griffin, W.L., Huston, D.L., Hickman, A.H., Champion, D.C., Anhaeusser, C.R., Pirajno, F.Making it thick: a volcanic plateau origin of Paleoarchean continental lithosphere of the Pilbara and Kaapvaal cratons.Geological Society of London Special Publication: Continent formation through time., No. 389, pp. 83-111.Australia, Africa, South AfricaGeotectonics
DS201504-0231
2015
Griffin, W.L.Xiong, Q., Griffin, W.L., Zheng, J-P., O'Reilly, S.Y., Pearson, N.J.Episodic refertilization and metasomatism of Archean mantle: evidence from an orogenic peridotite in North Qaidam ( NE Tibet) China.Contributions to Mineralogy and Petrology, Vol. 169, 24p.China, TibetPeridotite
DS201505-0246
2015
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Toledo, V., O'Reilly, S.Y., Jacob, D., Pearson, N.J.Corundum, moissanite and super reducing conditions in the upper mantle beneath the lower ( southern) Galilee ( Israel).Israel Geological Society, 1p.posterEurope, IsraelMineralogy
DS201506-0301
2015
Griffin, W.L.Zedgenizov, D.A., Pokhilenko, N.P., Griffin, W.L.Carbonate- silicate composition of diamond forming media of fibrous diamonds from Snap Lake area, Canada.Doklady Earth Sciences, Vol. 461, 1, pp. 297-300.Canada, Northwest TerritoriesMicro-inclusions
DS201508-0359
2015
Griffin, W.L.Howell, D., Fisher, D., Piazolo, S., Griffin, W.L., Sibley, S.J.Pink color in Type I diamonds: is deformation twinning the cause?American Mineralogist, Vol. 100, pp. 1518-1527.Australia, South America, VenezuelaDeposit - Argyle, Santa Elena
DS201508-0379
2015
Griffin, W.L.Wang, K-L., Prikhodko, V., O'Reilly, S.Y., Griffin, W.L., Pearson, N.J., Kovach, V., Lizuka, Y., Chien, Y-H.Ancient mantle lithosphere beneath the Khanka Massif in Russian Far-East: in situ Re-Os evidence.Terra Nova, Vol. 27, 4, pp. 277-284.RussiaGeochronology
DS201512-1984
2015
Griffin, W.L.Wang, K-L., Prikhodo, V., O'Reilly, S.Y., Griffin, W.L., Pearson, N.J., Kovach, V., Iizuka, Y., Chien, Y-H.Ancient mantle lithosphere beneath the Khanka massif in the Russian Far East: in situ Re-Os evidence.Terra Nova, Vol. 27, 4, pp. 277-284.RussiaGeochronology

Abstract: The Os-isotope compositions of sulphides in mantle xenoliths hosted by Late Miocene alkali basalts from the Sviyaginsky volcano, Russian Far East, reveal the presence of Archaean-Proterozoic subcontinental lithospheric mantle beneath the Khanka massif. Their TMA and TRD model ages reveal similar peaks at 1.1 and 0.8 Ga suggesting later thermotectonic events in the subcontinental lithospheric mantle, whereas TRD model ages range back to 2.8 ± 0.5 (2?) Ga. The events recognized in the subcontinental lithospheric mantle are consistent with those recorded in the crust of the Khanka massif. The sulphide Os-isotope data show that the subcontinental lithospheric mantle beneath the Khanka massif had formed at least by the Mesoproterozoic, and was subsequently metasomatized by juvenile crustal-growth events related to the evolution of the Altaids. The Khanka massif is further proposed to have tectonic affinity to the Siberia Craton and should originate from it accordingly.
DS201601-0051
2015
Griffin, W.L.Yang, J.S., Wirth, R., Wiedenbeck, M., Griffin, W.L., Meng, F.C., Chen, S.Y., Bai, W.J., Xu, X.X., Makeeyev, A.B., Bryanchaniniova, N.I.Diamonds and highly reduced minerals from chromitite of the Ray-Iz ophiolite of the Polar Urals: deep origin of podiform chromitites and ophiolitic diamonds.Acta Geologica Sinica, Vol. 89, 2, p. 107.Russia, Polar UralsOphiolite
DS201603-0381
2016
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Adams, D., Huang, J-X., Saunders, M.,Toledo, V., Pearson, N.J., O'Reilly, S.Y.Heaven on Earth: tistarite ( Ti203) and other nebular phases in corundum aggregates from Mt. Carmel volcanic rocks.Israel Geological Society, pp. 85-86. abstractEurope, IsraelMoissanite

Abstract: This ending talk, focused on the ongoing cooperative research of Prof. Griffin and his team at Macquarie University and Shefa Yamim, since January 2014, highlighting unique corundum species characteristics. Preliminary results of this research were presented in the IGS Annual Meeting of 2015, whereas this year Prof. Griffin has shared innovative findings only microscopically tracked within titanium-rich corundum aggregates. One of the more abundant minerals is Tistarite (Ti2O3), previously known only as a single grain in a primitive type of meteorite (!). An article has been submitted to a scientific journal detailing this first terrestrial occurrence. Several other minerals are common in meteorites, but unknown or extremely rare on Earth. About half of these minerals are unknown to science, and will be described as new minerals in the scientific literature. The first of these is a Titanium-Aluminium-Zirconium oxide, informally known as TAZ; it will be submitted to the International Mineralogical Association for recognition as a new mineral, ShefaTAZite. Using state of the art technologies such as Thermal Ionisation Mass Spectrometry (TIMS) and Electron Microscopy Facility (EMF) that has three scanning electron microscopes, all with EBSD capability, and a transmission electron microscope - Prof. Griffin revealed spectacular imagery of minerals and rare compounds associated with titanium rich corundum aggregates.
DS201603-0382
2016
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Adams, D., Toledo, V., Pearson, N.J., O'Reilly, S.Y.Deep-Earth methane, mantle dynamics and mineral exploration: insights from northern Israel, southern Tibet and Kamchatka.Israel Geological Society, pp. 87-88. abstractEurope, Israel, TibetMoissanite
DS201603-0407
2016
Griffin, W.L.O'Reilly, S.Y., Griffin, W.L., Pearson, N.J.The role of the deep lithosphere in metallogeny.Israel Geological Society, pp. 144-145. abstractMantleSCLM - geodynamics

Abstract: This talk shortly reviewed geological and geochemical mechanisms of the deep lithosphere, a layer composed of the Earth's crust and uppermost mantle at a depth range of 100-150km below the surface. Definition of these processes at depth, reflects on surface recovery of gem and heavy minerals, of which metallic minerals were stressed out. Prof. O'reilley has also referred to Shefa Yamim's exploration area in northern Israel where the eruption of gem-bearing volcanic rocks appears to be related to a major lithospheric suture (the Dead Sea Transform) and related faulting. The Dead Sea Transform is a 1000km plate boundary stretching out from Turkey in the north to Eilat Bay in the south. As such, it is a preferred pathway for magma emplacement crystalizing in volcanic bodies that are being surveyed by Shefa Yamim as Primary Sources for gem and heavy minerals.
DS201604-0597
2016
Griffin, W.L.Castilo-Oliver, M., Gali, S., Melgarejo, J.C., Griffin, W.L., Belousova, E., Pearson, N.J., Watangua, M., O'Reilly, S.Y.Trace element geochemistry and U-Pb dating of perovskite in kimberlites of the Lunda Norte province ( NE Angola): petrogenetic and tectonic implications.Chemical Geology, Vol. 426, pp. 118-134.Africa, AngolaGeochronology

Abstract: Perovskite (CaTiO3) has become a very useful mineral for dating kimberlite eruptions, as well as for constraining the compositional evolution of a kimberlitic magma and its source. Despite the undeniable potential of such an approach, no similar study had been done in Angola, the fourth largest diamond producer in Africa. Here we present the first work of in situ U-Pb geochronology and Sr-Nd isotope analyses of perovskite in six Angolan kimberlites, supported by a detailed petrographic and geochemical study of their perovskite populations. Four types of perovskite were identified, differing in texture, major- and trace-element composition, zoning patterns, type of alteration and the presence or absence of inclusions. Primary groundmass perovskite is classified either as anhedral, Na-, Nb- and LREE-poor perovskite (Ia); or euhedral, strongly zoned, Na-, Nb- and LREE-rich perovskite (Ib). Secondary perovskite occurs as reaction rims on ilmenite (IIa) or as high Nb (up to 10.6 wt% Nb2O5) perovskite rims on primary perovskite (IIb). The occurrence of these four types within the Mulepe kimberlites is interpreted as an evidence of a complex, multi-stage process that involved mingling of compositionally different melts. U-Pb dating of these perovskites yielded Lower Cretaceous ages for four of the studied kimberlites: Mulepe 1 (116.2 ± 6.5 Ma), Mulepe 2 (123.0 ± 3.6 Ma), Calonda (119.5 ± 4.3 Ma) and Cat115 (133 ± 10 Ma). Kimberlite magmatism occurred in NE Angola likely due to reactivation of deep-seated translithospheric faults (> 300 km) during the break-up of Gondwana. Sr-Nd isotope analyses of four of these kimberlites indicate that they are Group I kimberlites, which is consistent with the petrological observations.
DS201605-0819
2016
Griffin, W.L.Castillo-Oliver, M., Gali, S., Melgarejo, J.C., Griffin, W.L., Belousova, E., Pearson, N.J., Watangua, M., O'Reilly, S.Y.Trace element geochemistry and U-Pb dating of perovskite in kimberlites of the Lunda Norte province ( NE Angola): petrogenetic and tectonic implications.Chemical Geology, Vol. 426, pp. 118-134.Africa, AngolaDeposit - Alto Cuilo

Abstract: Perovskite (CaTiO3) has become a very usefulmineral for dating kimberlite eruptions, aswell as for constraining the compositional evolution of a kimberlitic magma and its source. Despite the undeniable potential of such an approach, no similar study had been done in Angola, the fourth largest diamond producer in Africa. Here we present the firstwork of in situ U-Pb geochronology and Sr-Ndisotope analyses of perovskite in six Angolan kimberlites, supported by a detailed petrographic and geochemical study of their perovskite populations. Four types of perovskitewere identified, differing in texture,major- and trace-element composition, zoning patterns, type of alteration and the presence or absence of inclusions. Primary groundmass perovskite is classified either as anhedral, Na-, Nb- and LREE-poor perovskite (Ia); or euhedral, strongly zoned, Na-, Nb- and LREE-rich perovskite (Ib). Secondary perovskite occurs as reaction rims on ilmenite (IIa) or as high Nb (up to 10.6 wt% Nb2O5) perovskite rims on primary perovskite (IIb). The occurrence of these four types within the Mulepe kimberlites is interpreted as an evidence of a complex, multi-stage process that involved mingling of compositionally different melts. U-Pb dating of these perovskites yielded Lower Cretaceous ages for four of the studied kimberlites: Mulepe 1 (116.2±6.5Ma),Mulepe 2 (123.0±3.6Ma), Calonda (119.5±4.3 Ma) and Cat115 (133±10Ma). Kimberlite magmatism occurred in NE Angola likely due to reactivation of deep-seated translithospheric faults (N300 km) during the break-up of Gondwana. Sr-Nd isotope analyses of four of these kimberlites indicate that they are Group I kimberlites, which is consistent with the petrological observations.
DS201606-1090
2016
Griffin, W.L.Griffin, W.L., Afonso, J.C., Belousova, E.A., Gain, S.E., Gong, X-H., Gonzalez-Jiminez, J.M., Howell, D., Huang, J-X., McGowan, N., Pearson, N.J., Satsukawa, T., Shi R., Williams, P., Xiong, Q., Yang, J-S., Zhang, M., O'Reilly, S.Y.Mantle recycling: transition zone metamorphism of Tibetan ophiolitic peridotites and its tectonic implications.Journal of Petrology, in press available, 30p.Asia, China, TibetPeridotite

Abstract: Large peridotite massifs are scattered along the 1500?km length of the Yarlung-Zangbo Suture Zone (southern Tibet, China), the major suture between Asia and Greater India. Diamonds occur in the peridotites and chromitites of several massifs, together with an extensive suite of trace phases that indicate extremely low fO2 (SiC, nitrides, carbides, native elements) and/or ultrahigh pressures (UHP) (diamond, TiO2 II, coesite, possible stishovite). New physical and isotopic (C, N) studies of the diamonds indicate that they are natural, crystallized in a disequilibrium, high-T environment, and spent only a short time at mantle temperatures before exhumation and cooling. These constraints are difficult to reconcile with previous models for the history of the diamond-bearing rocks. Possible evidence for metamorphism in or near the upper part of the Transition Zone includes the following: (1) chromite (in disseminated, nodular and massive chromitites) containing exsolved pyroxenes and coesite, suggesting inversion from a high-P polymorph of chromite; (2) microstructural studies suggesting that the chromitites recrystallized from fine-grained, highly deformed mixtures of wadsleyite and an octahedral polymorph of chromite; (3) a new cubic Mg-silicate, with the space group of ringwoodite but an inverse-spinel structure (all Si in octahedral coordination); (4) harzburgites with coarsely vermicular symplectites of opx + Cr-Al spinel ± cpx; reconstructions suggest that these are the breakdown products of majoritic garnets, with estimated minimum pressures to?>?13?GPa. Evidence for a shallow pre-metamorphic origin for the chromitites and peridotites includes the following: (1) trace-element data showing that the chromitites are typical of suprasubduction-zone (SSZ) chromitites formed by magma mixing or mingling, consistent with Hf-isotope data from magmatic (375?Ma) zircons in the chromitites; (2) the composition of the new cubic Mg-silicate, which suggests a low-P origin as antigorite, subsequently dehydrated; (3) the peridotites themselves, which carry the trace element signature of metasomatism in an SSZ environment, a signature that must have been imposed before the incorporation of the UHP and low-fO2 phases. A proposed P-T-t path involves the original formation of chromitites in mantle-wedge harzburgites, subduction of these harzburgites at c. 375?Ma, residence in the upper Transition Zone for >200 Myr, and rapid exhumation at c. 170-150?Ma or 130-120?Ma. Os-isotope data suggest that the subducted mantle consisted of previously depleted subcontinental lithosphere, dragged down by a subducting oceanic slab. Thermomechanical modeling shows that roll-back of a (much later) subducting slab would produce a high-velocity channelized upwelling that could exhume the buoyant harzburgites (and their chromitites) from the Transition Zone in?
DS201606-1093
2015
Griffin, W.L.Howell, D., Griffin, W.L., Yang, J., Gain, S., Stern, R.A., Huang, J-X., Jacob, D.E., Xu, X., Stokes, A.J., O'Reilly, S.Y., Pearson, N.J.Diamonds in ophiolites: contamination or a new diamond growth environment?Earth and Planetary Science Letters, Vol. 430, pp. 284-295.Asia, TibetLuobusa Massif Type Iib

Abstract: For more than 20 years, the reported occurrence of diamonds in the chromites and peridotites of the Luobusa massif in Tibet (a complex described as an ophiolite) has been widely ignored by the diamond research community. This skepticism has persisted because the diamonds are similar in many respects to high-pressure high-temperature (HPHT) synthetic/industrial diamonds (grown from metal solvents), and the finding previously has not been independently replicated. We present a detailed examination of the Luobusa diamonds (recovered from both peridotites and chromitites), including morphology, size, color, impurity characteristics (by infrared spectroscopy), internal growth structures, trace-element patterns, and C and N isotopes. A detailed comparison with synthetic industrial diamonds shows many similarities. Cubo-octahedral morphology, yellow color due to unaggregated nitrogen (C centres only, Type Ib), metal-alloy inclusions and highly negative View the MathML source?C13 values are present in both sets of diamonds. The Tibetan diamonds (n=3n=3) show an exceptionally large range in View the MathML source?N15 (?5.6 to +28.7‰+28.7‰) within individual crystals, and inconsistent fractionation between {111} and {100} growth sectors. This in contrast to large synthetic HPHT diamonds grown by the temperature gradient method, which have with View the MathML source?N15=0‰ in {111} sectors and +30‰+30‰ in {100} sectors, as reported in the literature. This comparison is limited by the small sample set combined with the fact the diamonds probably grew by different processes. However, the Tibetan diamonds do have generally higher concentrations and different ratios of trace elements; most inclusions are a NiMnCo alloy, but there are also some small REE-rich phases never seen in HPHT synthetics. These characteristics indicate that the Tibetan diamonds grew in contact with a C-saturated Ni-Mn-Co-rich melt in a highly reduced environment. The stable isotopes indicate a major subduction-related contribution to the chemical environment. The unaggregated nitrogen, combined with the lack of evidence for resorption or plastic deformation, suggests a short (geologically speaking) residence in the mantle. Previously published models to explain the occurrence of the diamonds, and other phases indicative of highly reduced conditions and very high pressures, have failed to take into account the characteristics of the diamonds and the implications for their formation. For these diamonds to be seriously considered as the result of a natural growth environment requires a new understanding of mantle conditions that could produce them.
DS201606-1094
2015
Griffin, W.L.Howell, D., Stern, R.A., Griffin, W.L., Southworth, R., Mikhail, S., Stachel, T.Nitrogen isotope systematics and origins of mixed habit diamonds.Geochimica et Cosmochimica Acta, Vol. 157, pp. 1-12.TechnologyDiamond morphology

Abstract: Nitrogen isotope values from mantle diamonds are a commonly used tracer in the quest to track volatiles within the Earth’s mantle through deep time. Interpretations of this isotope data are valid so long as stable isotope fractionation processes in the mantle are understood. The fractionation of nitrogen isotopes between {1 1 1} and {1 0 0} growth sectors is well documented for high-pressure high-temperature (HPHT) synthetic diamonds, but there is little data on whether it also occurs in natural mixed-habit diamonds. We present 91 in-situ nitrogen isotope (?15N) measurements, along with carbon isotope (?13C) values and nitrogen abundances [N], obtained from three mixed-habit diamonds by secondary ion mass spectrometry (SIMS). While the well-documented enrichment of nitrogen concentrations in octahedral sectors compared to contemporaneous cuboid sectors is observed, a similarly clear disparity is not obvious in the ?15N data. Whereas HPHT synthetic diamonds exhibit 15N enrichment in the {1 0 0} sectors by ?+30‰, the mixed-habit diamonds studied here show enrichment of the octahedral sectors in 15N by only 0.4-1‰. This major difference between HPHT synthetic and natural mixed-habit diamonds is proposed to be the result of different physical properties of the growth interfaces. The smooth interfaces of the octahedral sectors are the same in both types of crystal, but the outermost atoms on the smooth cube interfaces of an HPHT synthetic diamond behave differently to those on the rough cuboid interfaces of the natural mixed-habit diamonds, resulting in different ?15N values. Both the ?13C (average of ??8.7‰) and ?15N (average of ?0‰) data show only minor offsets from the typical mantle values (?13C = ?5 ± 3‰, ?15N = ?5 ± 4‰). This may indicate diamond formation from a mantle derived fluid/melt containing a minor subducted component (lowering ?13C values and elevating ?15N) or relate to moderate degrees of isotopic fractionation of a pure mantle fluid/melt by prior diamond precipitation. The homogeneous nature of both the carbon and nitrogen isotopic compositions of all three diamonds, however, documents continuous and unlimited supply of diamond forming fluid/melt, with a constant composition. Such homogenous isotopic compositions exclude fluid mixing or isotopic fractionation close to the site of diamond formation and preclude distinguishing between these two processes based on diamond analyses alone.
DS201610-1865
2016
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Adams, D.T., Huang, J-X., Saunders, M., Toledo, V., Pearson, N.J., O'Reilly, S.Y.First terrestrial occurrence of tistarite ( Ti2O3): ultra-low oxygen fugacity in the upper mantle beneath Mount Carmel, Israel.Geology, Vol. 44, 10, pp. 815-818.Europe, IsraelMoissanite

Abstract: The minimum oxygen fugacity (fO2) of Earth's upper mantle probably is controlled by metal saturation, as defined by the iron-wüstite (IW) buffer reaction (FeO ? Fe + O). However, the widespread occurrence of moissanite (SiC) in kimberlites, and a suite of super-reduced minerals (SiC, alloys, native elements) in peridotites in Tibet and the Polar Urals (Russia), suggest that more reducing conditions (fO2 = 6-8 log units below IW) must occur locally in the mantle. We describe pockets of melt trapped in aggregates of corundum crystals ejected from Cretaceous volcanoes in northern Israel which contain high-temperature mineral assemblages requiring extremely low fO2 (IW < -10). One abundant phase is tistarite (Ti2O3), previously known as a single grain in the Allende carbonaceous chondrite (Mexico) and believed to have formed during the early evolution of the solar nebula. It is associated with other reduced phases usually found in meteorites. The development of super-reducing conditions in Earth's upper mantle may reflect the introduction of CH4 + H2 fluids from the deep mantle, specifically related to deep-seated volcanic plumbing systems at plate boundaries.
DS201610-1872
2016
Griffin, W.L.Huang, J-X., Xiang, Y., An, Y., Griffin, W.L., Greau, Y., Xie, L., Pearson, N.J., Yu, H., O'Reilly, S.Y.Magnesium and oxygen isotopes in Roberts Victor eclogites.Chemical Geology, Vol. 438, pp. 73-83.Africa, South AfricaDeposit - Roberts Victor

Abstract: Magnesium and oxygen are critical elements in the solid Earth and hydrosphere. A better understanding of the combined behavior of Mg and O isotopes will refine their use as a tracer of geochemical processes and Earth evolution. In this study, the Mg-isotope compositions of garnet and omphacite separated from well-characterized xenolithic eclogites from the Roberts Victor kimberlite pipe (South Africa) have been measured by solution multi-collector ICP-MS. The reconstructed whole-rock ?26Mg values of Type I (metasomatized) eclogites range from ? 0.61‰ to ? 0.20‰ (Type IA) and from ? 0.60‰ to ? 0.30‰ (Type IB) (mean ? 0.43‰ ± 0.12‰), while ?26Mg of Type IIA (fresh, least metasomatized) eclogites ranges from ? 1.09‰ to ? 0.17‰ (mean ? 0.69‰ ± 0.41‰); a Type IIB (fresh, least metasomatized) has ?26Mg of ? 0.37‰. Oxygen-isotope compositions of garnet were analyzed in situ by SIMS (CAMECA 1280) and cross-checked by laser fluorination. Garnets have ?18O of 6.53‰ to 9.08‰ in Type IA, 6.14‰ to 6.65‰ in Type IB, and 2.34‰ to 2.91‰ in Type IIB. The variation of ?26Mg and ?18O in Type IA and IB eclogites is consistent with the previously proposed model for the evolution of these samples, based on major and trace elements and radiogenic isotopes. In this model, the protoliths (Type II eclogites) were metasomatized by carbonatitic to kimberlitic melts/fluids to produce first Type IA eclogites and then Type IB. Metasomatism has changed the O-isotope compositions, but the Mg-isotope compositions of Type IA are mainly controlled by the protoliths; those of Type IB eclogites reflect mixing between the protoliths and the kimberlitic melt/fluid. The combination of a large range of ?26Mg and low ?18O in Type II eclogites cannot be explained easily by seawater alteration of oceanic crust, interaction of carbonate/silicate sediments with oceanic crust, or partial melting of mafic rocks.
DS201610-1886
2016
Griffin, W.L.Melkovets, V.G., Rezvukhin, D.I., Belousova, E.A., Griffin, W.L., Sharygin, I.S., Tretiakova, I.G., Pokhilenko, N.P., Sobolev, N.V.Cr-rich rutile: a powerful tool for diamond exploration.Lithos, in press available 8p.Russia, SiberiaDeposit - Internationalnaya

Abstract: Mineralogical studies and U-Pb dating have been carried out on rutile included in peridotitic and eclogitic garnets from the Internatsionalnaya pipe, Mirny field, Siberian craton. We also describe a unique peridotitic paragenesis (rutile + forsterite + enstatite + Cr-diopside + Cr-pyrope) preserved in diamond from the Mir pipe, Mirny field. Compositions of rutile from the heavy mineral concentrates of the Internatsionalnaya pipe and rutile inclusions in crustal almandine-rich garnets from the Mayskaya pipe (Nakyn field), as well as from a range of different lithologies, are presented for comparison. Rutile from cratonic mantle peridotites shows characteristic enrichment in Cr, in contrast to lower-Cr rutile from crustal rocks and off-craton mantle. Rutile with Cr2O3 > 1.7 wt% is commonly derived from cratonic mantle, while rutiles with lower Cr2O3 may be both of cratonic and off-cratonic origin. New analytical developments and availability of standards have made rutile accessible to in situ U-Pb dating by laser ablation ICP-MS. A U-Pb age of 369 ± 10 Ma for 9 rutile grains in 7 garnets from the Internatsionalnaya pipe is consistent with the accepted eruption age of the pipe (360 Ma). The equilibrium temperatures of pyropes with rutile inclusions calculated using Ni-in-Gar thermometer range between ~ 725 and 1030 °C, corresponding to a depth range of ca ~ 100-165 km. At the time of entrainment in the kimberlite, garnets with Cr-rich rutile inclusions resided at temperatures well above the closure temperature for Pb in rutile, and thus U-Pb ages on mantle-derived rutile most likely record the emplacement age of the kimberlites. The synthesis of distinctive rutile compositions and U-Pb dating opens new perspectives for using rutile in diamond exploration in cratonic areas.
DS201611-2110
2016
Griffin, W.L.Giuliani, A., Soltys, A., Phillips, D., Kamenetsly, V.S., Maas, R., Geomann, K., Woodhead, J.D., Drysdale, R.N., Griffin, W.L.The final stages of kimberlite petrogenesis: petrography, mineral chemistry, melt inclusions and Sr-C-O isotope geochemistry of the Bultfontein kimberlite ( Kimberley, South Africa).Chemical Geology, in press available 15p.Africa, South AfricaDeposit - Bultfontein

Abstract: The petrogenesis of kimberlites commonly is obscured by interaction with hydrothermal fluids, including deuteric (late-magmatic) and/or groundwater components. To provide new constraints on the modification of kimberlite rocks during overprinting by such fluids and on the fractionation of kimberlite magmas during crystallisation, we have undertaken a detailed petrographic and geochemical study of a hypabyssal sample (BK) from the Bultfontein kimberlite (Kimberley, South Africa).
DS201611-2135
2016
Griffin, W.L.Rudloff-Grund, J., Brenker, F.E., Marquardt, K., Howell, D., Schrieber, A., O'Reilly, S.Y., Griffin, W.L., Kaminsky, F.V.Nitrogen nanoinclusions in milky diamonds from Juin a area, Mato Grosso State, Brazil.Lithos, in press available 34p.South America, Brazil, Mato GrossoDeposit - Juina
DS201612-2320
2016
Griffin, W.L.Malkovets, V.G., Rezvukhin, D.I., Belousova, E.A., Griffin, W.L., Sharygin, I.S., Tretiakov, I.G., Gibsher, A.A., O'Reilly, S.Y., Kuzmin, D.V., Litasov, K.D., Logvinova, A.M., Pokhilenko, N.P., Sobolev, N.V.Cr-rich rutile: a powerful tool for diamond exploration.Lithos, Vol. 265, pp. 304-311.Russia, SiberiaDeposit - Internationalskaya

Abstract: Mineralogical studies and U-Pb dating have been carried out on rutile included in peridotitic and eclogitic garnets from the Internatsionalnaya pipe, Mirny field, Siberian craton. We also describe a unique peridotitic paragenesis (rutile + forsterite + enstatite + Cr-diopside + Cr-pyrope) preserved in diamond from the Mir pipe, Mirny field. Compositions of rutile from the heavy mineral concentrates of the Internatsionalnaya pipe and rutile inclusions in crustal almandine-rich garnets from the Mayskaya pipe (Nakyn field), as well as from a range of different lithologies, are presented for comparison. Rutile from cratonic mantle peridotites shows characteristic enrichment in Cr, in contrast to lower-Cr rutile from crustal rocks and off-craton mantle. Rutile with Cr2O3 > 1.7 wt% is commonly derived from cratonic mantle, while rutiles with lower Cr2O3 may be both of cratonic and off-cratonic origin. New analytical developments and availability of standards have made rutile accessible to in situ U-Pb dating by laser ablation ICP-MS. A U-Pb age of 369 ± 10 Ma for 9 rutile grains in 6 garnets from the Internatsionalnaya pipe is consistent with the accepted eruption age of the pipe (360 Ma). The equilibrium temperatures of pyropes with rutile inclusions calculated using Ni-in-Gar thermometer range between ~ 725 and 1030 °C, corresponding to a depth range of ca ~ 100-165 km. At the time of entrainment in the kimberlite, garnets with Cr-rich rutile inclusions resided at temperatures well above the closure temperature for Pb in rutile, and thus U-Pb ages on mantle-derived rutile most likely record the emplacement age of the kimberlites. The synthesis of distinctive rutile compositions and U-Pb dating opens new perspectives for using rutile in diamond exploration in cratonic areas.
DS201612-2338
2016
Griffin, W.L.Skuzovatov, S., Zedgenizov, D., Howell, D., Griffin, W.L.Various growth environments of cloudy diamonds from Malobotuobia kimberlite field ( Siberian craton).Lithos, Vol. 265, pp. 96-107.Russia, SiberiaDeposit - Malobotuobia

Abstract: Microinclusions of high-density fluids (HDF's) occur in cloudy diamonds from the Mir and Internatsionalnaya kimberlite pipes (Malobotuobia kimberlite field, Siberian platform). These HDFs are of typical high-Mg carbonatitic composition; a few diamonds contain microinclusions that define a low-Mg carbonatitic to silicic trend. The observed variations are interpreted as resulted from mixing of two contrasting fluids derived from the partial melting mainly of carbonated peridotite (the high-Mg carbonatitic HDFs) and eclogite (silica-rich HDFs and HDFs with high Ca/(Ca + Mg + Fe)). Immiscibility of carbonatitic and silica-rich fluids provides a possible mechanism for the co-existence of the observed HDFs but needs further proof. The uniform carbon isotope composition of cloudy diamonds with high-Mg carbonatitic microinclusions from both kimberlite pipes implies a single peridotitic source.
DS201701-0002
2016
Griffin, W.L.An, Y., Huang, J-X., Griffin, W.L., Liu, C., Huang, F.Isotopic composition of Mg and Fe in garnet peridotites from the Kaapvaal and Siberian cratons.Geochimica et Cosmochimica Acta, in press available 45p.Africa, RussiaGeochronology

Abstract: We present Mg and Fe isotopic data for whole rocks and separated minerals (olivine, clinopyroxene, orthopyroxene, garnet, and phlogopite) of garnet peridotites that equilibrated at depths of 134-186 km beneath the Kaapvaal and Siberian cratons. There is no clear difference in ?26Mg and ?56Fe of garnet peridotites from these two cratons. ?26Mg of whole rocks varies from ?0.243‰ to ?0.204‰ with an average of ?0.225 ± 0.037‰ (2?, n = 19), and ?56Fe from ?0.038‰ to 0.060‰ with an average of ?0.003 ± 0.068‰ (2?, n = 19). Both values are indistinguishable from the fertile upper mantle, indicating that there is no significant Mg-Fe isotopic difference between the shallow and deep upper mantle. The garnet peridotites from ancient cratons show ?26Mg similar to komatiites and basalts, further suggesting that there is no obvious Mg isotopic fractionation during different degrees of partial melting of deep mantle peridotites and komatiite formation. The precision of the Mg and Fe isotope data (?±0.05‰ for ?26Mg and ?56Fe, 2?) allows us to distinguish inter-mineral isotopic fractionations. Olivines are in equilibrium with opx in terms of Mg and Fe isotopes. Garnets have the lowest ?26Mg and ?56Fe among the coexisting mantle minerals, suggesting the dominant control of crystal structure on the Mg-Fe isotopic compositions of garnets. Elemental compositions and mineralogy suggest that clinopyroxene and garnet were produced by later metasomatic processes as they are not in chemical equilibrium with olivine or orthopyroxene. This is consistent with the isotopic disequilibrium of Mg and Fe isotopes between orthopyroxene/olivine and garnet/clinopyroxene. Combined with one sample showing slightly heavy ?26Mg and much lighter ?56Fe, these disequilibrium features in the garnet peridotites reveal kinetic isotopic fractionation due to Fe-Mg inter-diffusion during reaction between peridotites and percolating melts in the Kaapvaal craton.
DS201701-0035
2016
Griffin, W.L.Tretiakova, I.G., Belousova, E.A., Malkovets, V.G., Griffin, W.L., Piazolo, S., Pearson, N.J., O'Reilly, S.Y., Nishido, H.Recurrent magmatic activity on a lithosphere scale structure: crystallization and deformation in kimberlitic zircons.Gondwana Research, Vol. 42, pp. 126-132.RussiaDeposit - Nubinskaya

Abstract: Kimberlites are not only the most economically important source of diamonds; they also carry unique information encapsulated in rock fragments entrained as the magma traverses the whole thickness of the lithosphere. The Nurbinskaya pipe in the Siberian kimberlite province (Russia) is one of several intruded along the Vilyui Rift, a major terrane boundary. The pipe contains three populations of mantle-derived zircon xenocrysts: Archean (mean age 2709 ± 9 Ma), Devonian (mean age 371 ± 2.3 Ma), and a subset of grains with evidence of brittle deformation and rehealing, and a range of ages between 370 and 450 Ma. The Hf-isotope, O-isotope and trace-element signatures of the last group provide a link between the Archean and Devonian events, indicating at least three episodes of magmatic activity and zircon crystallization in the lithosphere beneath the pipe. The emplacement of the Nurbinskaya pipe ca 370 Ma ago was only the youngest activity in a magma plumbing system that has been periodically reactivated over at least 2.7 billion years, controlled by the lithosphere-scale structure of the Vilyui Rift.
DS201702-0192
2017
Griffin, W.L.An, Y., Huang, J-X., Griffin, W.L., Liu, C., Huang, F.Isotopic composition of Mg and Fe in garnet peridotites from the Kaapvaal and Siberian cratons.Geochimica et Cosmochimica Acta, Vol. 200, pp. 167-185.Africa, South Africa, RussiaMetasomatism

Abstract: We present Mg and Fe isotopic data for whole rocks and separated minerals (olivine, clinopyroxene, orthopyroxene, garnet, and phlogopite) of garnet peridotites that equilibrated at depths of 134-186 km beneath the Kaapvaal and Siberian cratons. There is no clear difference in ?26Mg and ?56Fe of garnet peridotites from these two cratons. ?26Mg of whole rocks varies from ?0.243 to ?0.204 with an average of ?0.225 ± 0.037 (2?, n = 19), and ?56Fe from ?0.038‰ o 0.060 with an average of ?0.003 ± 0.068 (2?, n = 19). Both values are indistinguishable from the fertile upper mantle, indicating that there is no significant Mg-Fe isotopic difference between the shallow and deep upper mantle. The garnet peridotites from ancient cratons show ?26Mg similar to komatiites and basalts, further suggesting that there is no obvious Mg isotopic fractionation during different degrees of partial melting of deep mantle peridotites and komatiite formation. The precision of the Mg and Fe isotope data (±0.05 for ?26Mg and ?56Fe, 2?) allows us to distinguish inter-mineral isotopic fractionations. Olivines are in equilibrium with opx in terms of Mg and Fe isotopes. Garnets have the lowest ?26Mg and ?56Fe among the coexisting mantle minerals, suggesting the dominant control of crystal structure on the Mg-Fe isotopic compositions of garnets. Elemental compositions and mineralogy suggest that clinopyroxene and garnet were produced by later metasomatic processes as they are not in chemical equilibrium with olivine or orthopyroxene. This is consistent with the isotopic disequilibrium of Mg and Fe isotopes between orthopyroxene/olivine and garnet/clinopyroxene. Combined with one sample showing slightly heavy ?26Mg and much lighter ?56Fe, these disequilibrium features in the garnet peridotites reveal kinetic isotopic fractionation due to Fe-Mg inter-diffusion during reaction between peridotites and percolating melts in the Kaapvaal craton.
DS201702-0254
2017
Griffin, W.L.Xu, B., Griffin, W.L., Xiong, Q., Hou, Z-Q, O'Reilly, S.Y., Guo, Z., Pearson, N.J., Greau, Y., Yang, Z-M., Zheng, Y-C.Ultrapotassic rocks and xenoliths from South Tibet: contrasting styles of interaction between lithospheric mantle and asthenosphere during continental collision.Geology, Vol. 45, 1, pp. 51-54.China, TibetUPR - metasomatism

Abstract: Widespread Miocene (24-8 Ma) ultrapotassic rocks and their entrained xenoliths provide information on the composition, structure, and thermal state of the sub-continental lithospheric mantle in southern Tibet during the India-Asia continental collision. The ultrapotassic rocks along the Lhasa block delineate two distinct lithospheric domains with different histories of depletion and enrichment. The eastern ultrapotassic rocks (89°E-92°E) reveal a depleted, young, and fertile lithospheric mantle (87Sr/86Srt = 0.704-0.707 [t is eruption time]; Hf depleted-mantle model age [TDM] = 377-653 Ma). The western ultrapotassic rocks (79°E-89°E) and their peridotite xenoliths (81°E) reflect a refractory harzburgitic mantle refertilized by ancient metasomatism (lavas: 87Sr/86Srt = 0.714-0.734; peridotites: 87Sr/86Srt = 0.709-0.716). These data integrated with seismic tomography suggest that upwelling asthenosphere was diverted away from the deep continental root beneath the western Lhasa block, but rose to shallower depths beneath a thinner lithosphere in the eastern part. Heating of the lithospheric mantle by the rising asthenosphere ultimately generated the ultrapotassic rocks with regionally distinct geochemical signatures reflecting the different nature of the lithospheric mantle.
DS201704-0617
2017
Griffin, W.L.An, Y., Huang, J-X., Griffin, W.L.,Liu, C., Huang, F.Isotopic composition of Mg and Fe in garnet peridotites from the Kaapvaal and Siberian cratons.Geochimica et Cosmochimica Acta, Vol. 200, pp. 167-185.Africa, South Africa, RussiaCraton, Peridotite

Abstract: We present Mg and Fe isotopic data for whole rocks and separated minerals (olivine, clinopyroxene, orthopyroxene, garnet, and phlogopite) of garnet peridotites that equilibrated at depths of 134-186 km beneath the Kaapvaal and Siberian cratons. There is no clear difference in ?26Mg and ?56Fe of garnet peridotites from these two cratons. ?26Mg of whole rocks varies from ?0.243‰ to ?0.204‰ with an average of ?0.225 ± 0.037‰ (2?, n = 19), and ?56Fe from ?0.038‰ 0.060 with an average of ?0.003 ± 0.068‰ (2?, n = 19). Both values are indistinguishable from the fertile upper mantle, indicating that there is no significant Mg-Fe isotopic difference between the shallow and deep upper mantle. The garnet peridotites from ancient cratons show ?26Mg similar to komatiites and basalts, further suggesting that there is no obvious Mg isotopic fractionation during different degrees of partial melting of deep mantle peridotites and komatiite formation. The precision of the Mg and Fe isotope data (?±0.05‰ for ?26Mg and ?56Fe, 2?) allows us to distinguish inter-mineral isotopic fractionations. Olivines are in equilibrium with opx in terms of Mg and Fe isotopes. Garnets have the lowest ?26Mg and ?56Fe among the coexisting mantle minerals, suggesting the dominant control of crystal structure on the Mg-Fe isotopic compositions of garnets. Elemental compositions and mineralogy suggest that clinopyroxene and garnet were produced by later metasomatic processes as they are not in chemical equilibrium with olivine or orthopyroxene. This is consistent with the isotopic disequilibrium of Mg and Fe isotopes between orthopyroxene/olivine and garnet/clinopyroxene. Combined with one sample showing slightly heavy ?26Mg and much lighter ?56Fe, these disequilibrium features in the garnet peridotites reveal kinetic isotopic fractionation due to Fe-Mg inter-diffusion during reaction between peridotites and percolating melts in the Kaapvaal craton.
DS201706-1094
2017
Griffin, W.L.Lu, J-G, Xiong, Q., Griffin, W.L., Zheng, J-P., Huang, J-X., O'Reilly, S.Y., Satsuskawa, T., Pearson, N.J.Uplift of the southeastern Australian lithosphere: thermal tectonic evolution of garnet pyroxenite xenoliths from western Victoria.Geological Society of America, SPE 526 pp. 27-48.Australiageothermometry

Abstract: Detailed petrography, microstructure, and geochemistry of garnet pyroxenite xenoliths in Holocene basanite tuffs from maars at Lakes Bullenmerri and Gnotuk (western Victoria, southeastern Australia) have been used to track their igneous and metamorphic history, enabling the reconstruction of the thermal-tectonic evolution of the lithospheric mantle. The exsolution of orthopyroxene and garnet and rare spinel, plagioclase, and ilmenite from complex clinopyroxene megacrysts suggests that the xenoliths originally were clinopyroxene-dominant cumulates associated with minor garnet, orthopyroxene, or spinel. The compositions of exsolved phases and their host clinopyroxene were reintegrated using measured modal proportions to show that the primary clinopyroxene was enriched in Al2O3 (5.53-13.63 wt%) and crystallized at ~1300-1500 °C and 16-30 kbar. These cumulates then underwent extensive exsolution, recrystallization, and reaction during cooling, and finally equilibrated at ~950-1100 °C and 12-18 kbar before entrainment in the basanites. Rare earth element (REE) thermobarometry of garnets and coexisting clinopyroxenes preserves evidence of an intermediate stage (1032 °C and 21 kbar). These results imply that the protoliths of the garnet pyroxenite formed at a range of depths from ~50 to 100 km, and then during or shortly after cooling, they were tectonically emplaced to higher levels (~40-60 km; i.e., uplifted by at least 10-20 km) along the prevailing geotherm. This uplift may have been connected with lithosphere-scale faulting during the Paleozoic orogeny, or during Mesozoic-Cenozoic rifting of eastern Australia.
DS201707-1327
2017
Griffin, W.L.Giuliani, A., Soltys, A., Phillips, D., Kamenetsky, V.S., Maas, R., Goemann, K., Woodhead, J.D., Drysdale, R.N., Griffin, W.L.The final stages of kimberlite petrogenesis: petrography, mineral chemistry, melt inclusions and Sr-C-O isotope geochemistry of the Bultfontein kimberlite ( Kimberley, South Africa.Chemical Geology, Vol. 455, pp. 342-256.Africa, South Africadeposit - Bultfontein

Abstract: The petrogenesis of kimberlites is commonly obscured by interaction with hydrothermal fluids, including deuteric (late-magmatic) and/or groundwater components. To provide new constraints on the modification of kimberlite rocks during fluid interaction and the fractionation of kimberlite magmas during crystallisation, we have undertaken a detailed petrographic and geochemical study of a hypabyssal sample (BK) from the Bultfontein kimberlite (Kimberley, South Africa). Sample BK consists of abundant macrocrysts (> 1 mm) and (micro-) phenocrysts of olivine and lesser phlogopite, smaller grains of apatite, serpentinised monticellite, spinel, perovskite, phlogopite and ilmenite in a matrix of calcite, serpentine and dolomite. As in kimberlites worldwide, BK olivine grains consist of cores with variable Mg/Fe ratios, overgrown by rims that host inclusions of groundmass phases (spinel, perovskite, phlogopite) and have constant Mg/Fe, but variable Ni, Mn and Ca concentrations. Primary multiphase inclusions in the outer rims of olivine and in Fe-Ti-rich (‘MUM’) spinel are dominated by dolomite, calcite and alkali carbonates with lesser silicate and oxide minerals. Secondary inclusions in olivine host an assemblage of Na-K carbonates and chlorides. The primary inclusions are interpreted as crystallised alkali-Si-bearing Ca-Mg-rich carbonate melts, whereas secondary inclusions host Na-K-rich C-O-H-Cl fluids. In situ Sr-isotope analyses of groundmass calcite and perovskite reveal similar 87Sr/86Sr ratios to perovskite in the Bultfontein and the other Kimberley kimberlites, i.e. magmatic values. The ?18O composition of the BK bulk carbonate fraction is above the mantle range, whereas the ?13C values are similar to those of mantle-derived magmas. The occurrence of different generations of serpentine and occasional groundmass calcite with high 87Sr/86Sr, and elevated bulk carbonate ?18O values indicate that the kimberlite was overprinted by hydrothermal fluids, which probably included a significant groundwater component. Before this alteration the groundmass included calcite, monticellite, apatite and minor dolomite, phlogopite, spinel, perovskite and ilmenite. Inclusions of groundmass minerals in olivine rims and phlogopite phenocrysts show that olivine and phlogopite also belong to the magmatic assemblage. We therefore suggest that the crystallised kimberlite was produced by an alkali-bearing, phosphorus-rich, silica-dolomitic melt. The alkali-Si-bearing Ca-Mg-rich carbonate compositions of primary melt inclusions in the outer rims of olivine and in spinel grains with evolved compositions (MUM spinel) support formation of these melts after fractionation of abundant olivine, and probably other phases (e.g., ilmenite and chromite). Finally, the similarity between secondary inclusions in kimberlite olivine of this and other worldwide kimberlites and secondary inclusions in minerals of carbonatitic, mafic and felsic magmatic rocks, suggests trapping of residual Na-K-rich C-O-H-Cl fluids after groundmass crystallisation. These residual fluids may have persisted in pore spaces within the largely crystalline BK groundmass and subsequently mixed with larger volumes of external fluids, which triggered serpentine formation and localised carbonate recrystallisation.
DS201707-1371
2017
Griffin, W.L.Spetius, Z.V., Cliff, J., Griffin, W.L., O'Reilly, S.Y.Carbon isotopes of eclogite hosted diamonds from the Nyurbinskaya kimberlite pipe, Yakutia: the metasomatic origin of diamonds.Chemical Geology, Vol. 455, pp. 131-147.Russia, Yakutiadeposit - Nyurbinskaya

Abstract: Carbon isotope compositions and the distribution of nitrogen and hydrogen in diamonds from 18 eclogites from Nurbinskaya kimberlites were studied in situ in polished plates. Cathodoluminescence images show that most of the diamonds have complex growth structures with distinctive core, intermediate and rim zones. In some diamonds the cores display dissolution features, and intermediate growth zones are separated from the cores by narrow rounded oscillatory zones. At least three crystals show interrupted multistage diamond growth; variations in ?13C of 2–3‰ occur across the contacts between distinct zones. Generally, ?13C within the diamond cores varies only by 1–2‰, in rare cases up to 3.3‰. ?13C values are usually lower in the intermediate zones and drop further towards the rims by up to 3‰. High-resolution SIMS profiles show that variations in ?13C across the diamond growth zones are sharp with no evidence of diffusive relaxation. Diamonds with predominantly tangential octahedral growth have a wide range in ?13C from ? 15.2‰ up to 9.0‰ (± 0.4‰), and their nitrogen (N) contents vary between 30 and 1500 at. ppm. Six diamonds show little internal variation along the isotopic profiles with changes in ?13C of only 0.3–0.9‰ around mean values ranging from ? 6‰ to ? 3‰. Five crystals are isotopically heavy, with relatively homogeneous ?13C up to 9‰. FTIR data show markedly different N concentrations and nitrogen aggregation states between major growth zones. This implies that the diamonds in eclogitic xenoliths from Nyurbinskaya pipe grew in multiple and interrupted growth events, probably from fluids enriched in K and H. The wide variations of ?13C in the studied eclogitic diamonds and identification of their anomalously positive ?13C values, combined with the wide range of high ?18O in garnets from the diamondiferous xenoliths of the Nyurbinskaya pipe, which are mostly outside of the mantle range, suggest a crustal contribution to the parental mantle-related fluids forming diamonds in these xenoliths and indicate the complex metasomatic evolution of the lithospheric mantle beneath the Nakynsky kimberlite field.
DS201708-1576
2017
Griffin, W.L.Lu, J-G., Xiong, Q., Griffin, W.L., Zheng, J-P., Huang, J-X., O'Reilly, S.Y., Satsukawa, T., Pearson, N.J.Uplift of southeastern Australian lithosphere: thermal tectonic evolution of garnet pyroxenite xenoliths from western Victoria.Geological Society of London, Chapter 2, pp. 27-48.Australia, Victoriaxenoliths

Abstract: Detailed petrography, microstructure, and geochemistry of garnet pyroxenite xenoliths in Holocene basanite tuffs from maars at Lakes Bullenmerri and Gnotuk (western Victoria, southeastern Australia) have been used to track their igneous and metamorphic history, enabling the reconstruction of the thermal-tectonic evolution of the lithospheric mantle. The exsolution of orthopyroxene and garnet and rare spinel, plagioclase, and ilmenite from complex clinopyroxene megacrysts suggests that the xenoliths originally were clinopyroxene-dominant cumulates associated with minor garnet, orthopyroxene, or spinel. The compositions of exsolved phases and their host clinopyroxene were reintegrated using measured modal proportions to show that the primary clinopyroxene was enriched in Al2O3 (5.53–13.63 wt%) and crystallized at ~1300–1500 °C and 16–30 kbar. These cumulates then underwent extensive exsolution, recrystallization, and reaction during cooling, and finally equilibrated at ~950–1100 °C and 12–18 kba
DS201709-1998
2017
Griffin, W.L.Henry, H., Afonso, J.C., Satsukawa, T., Griffin, W.L., O'Reilly, S.Y., Kaczmarek, M-A., Tilhac, R., Gregoire, M., Ceuleneer, G.The unexplored potential impact of pyroxenite layering on upper mantle seismic properties.Goldschmidt Conference, abstract 1p.Europe, Spain, United States, Californiageophysics - seismics

Abstract: It is now accepted that significant volumes of pyroxenites are generated in the subduction factory and remain trapped in the mantle. In ophiolites and orogenic massifs the geometry of pyroxenite layers and their relationships with the host peridotite can be observed directly. Since a large part of what is known about the upper mantle structure is derived from the analysis of seismic waves, it is crucial to integrate pyroxenites in the interpretations. We modeled the seismic properties of a peridotitic mantle rich in pyroxenite layers in order to determine the impact of layering on the seimsic properties. To do so, EBSD data on deformed and undeformed pyroxenites from the Cabo Ortegal complex (Spain) and the Trinity ophiolite (California, USA) respectively are combined with either A or B-type olivine fabrics in order to model a realistic pyroxenite-rich upper mantle. Consideration of pyroxeniterich domains within the host mantle wall rock is incorporated in the calculations using the Schoenberg and Muir group theory [1]. This quantification reveals the complex dependence of the seismic signal on the deformational state and relative abundance of each mineral phase. The incorporation of pyroxenites properties into geophysical interpretations in understanding the lithospheric structure of subduction zones will lead to more geologically realistic models.
DS201709-1999
2017
Griffin, W.L.Huang, J-X., Xiong, Q., Griffin, W.L., Martin, L., Toledo, V., O'Reilly, S.Y.Moissanite in volcanic systems: super reduced conditions in the mantle.Goldschmidt Conference, abstract 1p.Mantlemoissanite

Abstract: Moissanite (SiC) occurs in mantle and mantle-generated rocks from different tectonic settings. SiC is stable only at low oxygen fugacity (ƒO2) ?IW. Israeli SiC is assiociated with corundum, Fe globules, native V and other phases in Cretaceous pyroclastic rocks from Mt Carmel and associated alluvial deposits[1]. The SiC grains contain inclusions of Si metal, FeSi2, FeTiSi2, FeAlSi2 and CaSi2+xSi2-x, which were liquids before being trapped during SiC crystallization. SiC has been found included in corundum, associated with Fe-Ti silicides, connecting the formation of SiC, reduced melts in corundum and conrundum itself. All grains are of the 6H polytype. ?13C ranges from - 32.1 to -24.5‰ and ?30Si from -0.68 to +1.42‰. These SiC grains are one product of the interaction of basaltic magma and mantle methane in a volcanic plumbing system. SiC crystallized from metallic melts that became immiscible during the reduction of the magma. Its low ?13C may reflect Rayleigh fractionation under reduced conditions; the variation in Si isotopes may reflect fractionation between SiC and immiscible metallic melts. SiC samples from the Udachnaya and Mir kimberlite pipes contain inclusions of Si metal, FeSi2, FeSi, FeTiSi2, Si(N,O). The SiC has ?13C ranging from -28.5 to -24.8‰, and ?30Si from -1.72 to +1.42‰. SiC from harzburgites, chromitites and pyroxenites of the Tibetan Zedang ophiolites have inclusions of Si metal and unmixed Fe-Ni-Ti-Si alloy. Their ?13C ranges from -30.6 to -24.7‰ and ?30Si from -0.85 to +1.26‰. SiC samples from these different settings show very similar characteristics, implying that they may be formed in similar mantle conditions, where the flux of mantle methane gradually reduces magmas and interacts with them to produce different reduced phases at different stages.
DS201710-2280
2017
Griffin, W.L.Xiong, Q., Griffin, W.L., Huang, J-X., Gain, S.E.M., Toledo, V., Pearson, N.J., O'Reilly, S.Y.Super reduced assemblages in "ophiolitic" chromitites and peridotites: the view from Mount Carmel.European Journal of Mineralogy, Vol. 29, 4, pp. 557-570.Europe, Israelmineralogy

Abstract: Ultrahigh-pressure (UHP) materials (e.g., diamond, high-pressure polymorph of chromite) and super-reduced (SuR) phases (e.g., carbides, nitrides, silicides and native metals) have been identified in chromitites and peridotites of the Tibetan and Polar-Urals ophiolites. These unusual assemblages suggest previously unrecognized fluid- or melt-related processes in the Earth’s mantle. However, the origin of the SuR phases, and in particular their relationships with the UHP materials in the ophiolites, are still enigmatic. Studies of a recently recognized SuR mineral system from Cretaceous volcanics on Mt Carmel, Israel, suggest an alternative genesis for the ophiolitic SuR phases. The Mt Carmel SuR mineral system (associated with Ti-rich corundum xenocrysts) appears to reflect the local interaction of mantle-derived CH4 ± H2 fluids with basaltic magmas in the shallow lithosphere (depths of ?30-100 km). These interactions produced desilication of the magma, supersaturation in Al2O3 leading to rapid growth of corundum, and phase assemblages requiring local oxygen fugacity (fO2) gradually dropping to ?11 log units below the iron-wüstite (IW) buffer. The strong similarities between this system and the SuR phases and associated Ti-rich corundum in the Tibetan and Polar-Urals ophiolites suggest that the ophiolitic SuR suite probably formed by local influx of CH4 ± H2 fluids within previously subducted peridotites (and included chromitites) during their rapid exhumation from the deep upper mantle to lithospheric levels. In the final stages of their ascent, the recycled peridotites and chromitites were overprinted by a shallow magmatic system similar to that observed at Mt Carmel, producing most of the SuR phases and eventually preserving them within the Tibetan and Polar-Urals ophiolites.
DS201711-2501
2015
Griffin, W.L.Begg, G.C., Griffin, W.L., O'Reilly, S.Y., Natapov, L.Geoscience dat a integration: insights into mapping lithospheric architecture.ASEG-PESA 2015, 2 p. abstract Mantledata integration

Abstract: In order to develop a 4D understanding of the architecture of the entire lithosphere, it is necessary to embrace integration of multi-disciplinary, multi-scale data in a GIS environment. An holistic understanding has evolved whereby geologic, geochemical and geophysical signals are consistent with a subcontinental lithospheric mantle (SCLM) dominated by a mosaic of domains of Archean ancestry, variably overprinted by subsequent tectonothermal events. Pristine Archean SCLM is mostly highly depleted (high Mg#), low density, high velocity and highly resistive, and preserves intact Archean crust. There is a first order relationship between changes to these signals and the degree of tectonothermal overprint (by melts, fluids). Continental crust is comprised largely of reconstituted Archean components, variably diluted by juvenile addition, symptomatic of the various overprinting events. These events impart crustal fabrics and patterns dictated by SCLM architecture, influenced by the free surface and crust-mantle decoupling.
DS201711-2506
2017
Griffin, W.L.Castillo-Oliver, M., Melgarejo, J.C., Gali, S., Pervov, V., Goncalves, A.O., Griffin, W.L., Pearson, N.J., O'Reilly, S.Y.Use and misuse of Mg- and Mn- rich ilmenite in diamond exploration: a petrographic and trace element approach. Congo-Kasai cratonLithos, Vol. 292-293, pp. 348-363.Africa, Angoladeposit - CAT115, Tchiuzo

Abstract: Magnesian ilmenite is a common kimberlite indicator mineral, although its use in diamond exploration is still controversial. Complex crystallisation and replacement processes have been invoked to explain the wide compositional and textural ranges of ilmenite found in kimberlites. This work aims to shed light on these processes, as well as their implications for diamond exploration. Petrographic studies were combined for the first time with both major- and trace-element analyses to characterise the ilmenite populations found in xenoliths and xenocrysts in two Angolan kimberlites (Congo-Kasai craton). A multi-stage model describes the evolution of ilmenite in these pipes involving: i) crystallisation of ferric and Mg-rich ilmenite either as metasomatic phases or as megacrysts, both in crustal and in metasomatised mantle domains; ii) kimberlite entrainment and xenolith disaggregation producing at least two populations of ilmenite nodules differing in composition; iii) interaction of both types with the kimberlitic magma during eruption, leading to widespread replacement by Mg-rich ilmenite along grain boundaries and fractures. This process produced similar major-element compositions in ilmenites regardless of their primary (i.e., pre-kimberlitic) origin, although the original enrichment in HFSE (Zr, Hf, Ta, Nb) observed in Fe3 +-rich xenocrysts is preserved. Finally (iv) formation of secondary Mn-ilmenite by interaction with a fluid of carbonatitic affinity or by infiltration of a late hydrothermal fluid, followed in some cases by subsolidus alteration in an oxidising environment. The complexities of ilmenite genesis may lead to misinterpretation of the diamond potential of a kimberlite during the exploration stage if textural and trace-element information is disregarded. Secondary Mg-enrichment of ilmenite xenocrysts is common and is unrelated to reducing conditions that could favour diamond formation/preservation in the mantle. Similarly, Mn-rich ilmenite should be disregarded as a diamond indicator mineral, unless textural studies can prove its primary origin.
DS201711-2514
2017
Griffin, W.L.Gonzalez-Jimenez, J.M., Camprubi, A., Colas, V., Griffin, W.L., Proenza, J.A., O'Reilly, S.Y., Centeno-Garcia, El., Garcia-Casco, A., Belousova, E., Talavera, C., Farre-de-Pablo, J., Satsukawa, T.The recycling of chromitites in ophiolites from southwestern North America. ( Baja)Lithos, in press available, 52p.United States, Californiachromitites

Abstract: Podiform chromitites occur in mantle peridotites of the Late Triassic Puerto Nuevo Ophiolite, Baja California Sur State, Mexico. These are high-Cr chromitites [Cr# (Cr/Cr + Al atomic ratio = 0.61-0.69)] that contain a range of minor- and trace-elements and show whole-rock enrichment in IPGE (Os, Ir, Ru). That are similar to those of high-Cr ophiolitic chromitites crystallised from melts similar to high-Mg island-arc tholeiites (IAT) and boninites in supra-subduction-zone mantle wedges. Crystallisation of these chromitites from S-undersaturated melts is consistent with the presence of abundant inclusions of platinum-group minerals (PGM) such as laurite (RuS2)-erlichmanite (OsS2), osmium and irarsite (IrAsS) in chromite, that yield TMA ? TRD model ages peaking at ~ 325 Ma. Thirty-three xenocrystic zircons recovered from mineral concentrates of these chromitites yield ages (2263 ± 44 Ma to 278 ± 4 Ma) and Hf-O compositions [?Hf(t) = ? 18.7 to + 9.1 and 18O values < 12.4‰] that broadly match those of zircons reported in nearby exposed crustal blocks of southwestern North America. We interpret these chromitite zircons as remnants of partly digested continental crust or continent-derived sediments on oceanic crust delivered into the mantle via subduction. They were captured by the parental melts of the chromitites when the latter formed in a supra-subduction zone mantle wedge polluted with crustal material. In addition, the Puerto Nuevo chromites have clinopyroxene lamellae with preferred crystallographic orientation, which we interpret as evidence that chromitites have experienced high-temperature and ultra high-pressure conditions (< 12 GPa and ~ 1600 °C). We propose a tectonic scenario that involves the formation of chromitite in the supra-subduction zone mantle wedge underlying the Vizcaino intra-oceanic arc ca. 250 Ma ago, deep-mantle recycling, and subsequent diapiric exhumation in the intra-oceanic basin (the San Hipólito marginal sea) generated during an extensional stage of the Vizcaino intra-oceanic arc ca. 221 Ma ago. The TRD ages at ~ 325 Ma record a partial melting event in the mantle prior to the construction of the Vizcaino intra-oceanic arc, which is probably related to the Permian continental subduction, dated at ~ 311 Ma.
DS201801-0060
2018
Griffin, W.L.Shatsky, V.S., Malkovets, V.G., Belousova, E.A., Tretiakova, I.G., Griffin, W.L., Ragozin, A.L., Wang, Q., Gibsher, A.A., O'Reilly, S.Y.Multi-stage modification of Paleoarchean crust beneath the Anabar tectonic province ( Siberian craton).Precambrian Research, Vol. 305, pp. 125-144.Russiacraton - Siberian

Abstract: According to present views, the crustal terranes of the Anabar province of the Siberian craton were initially independent blocks, separated from the convecting mantle at 3.1 (Daldyn terrane), 2.9 (Magan terrane) and 2.5?Ga (Markha terrane) (Rosen, 2003, 2004; Rosen et al., 1994, 2005, 2009). Previous studies of zircons in a suite of crustal xenoliths from kimberlite pipes of the Markha terrane concluded that the evolution of the crust of the Markha terrane is very similar to that of the Daldyn terrane. To test this conclusion we present results of U-Pb and Hf-isotope studies on zircons in crustal xenoliths from the Zapolyarnaya kimberlite pipe (Upper Muna kimberlite field), located within the Daldyn terrane, and the Botuobinskaya pipe (Nakyn kimberlite field) in the center of the Markha terrane. The data on xenoliths from the Botuobinskaya kimberlite pipe record tectonothermal events at 2.94, 2.8, 2.7 and 2?Ga. The event at 2?Ga caused Pb loss in zircons from a mafic granulite. U-Pb dating of zircons from the Zapolyarnaya pipe gives an age of 2.7?Ga. All zircons from the studied crustal xenoliths have Archean Hf model ages ranging from 3.65 to 3.11?Ga. This relatively narrow range suggests that reworking of the ancient crust beneath the Nakyn and Upper Muna kimberlite fields was minor, compared with the Daldyn and Alakit-Markha fields (Shatsky et al., 2016). This study, when combined with dating of detrital zircons, implies that tectonic-thermal events at 2.9-2.85, 2.75-2.7 and 2.0-1.95?Ga occurred everywhere on the Anabar tectonic province, and could reflect the upwelling of superplumes at 2.9, 2.7 and 2?Ga. The presence of the same tectonic-thermal events in the Daldyn and Markha terranes (Rosen et al., 2006a,b) supports the conclusion that the identification of the Markha terrane as a separate unit is not valid.
DS201805-0940
2018
Griffin, W.L.Chasse, M., Griffin, W.L., Alard, O., O'Reilly, S.Y., Calas, G.Insights into the mantle geochemistry of scandium from a meta-analysis of garnet data. GEOROC databaseLithos, in press available 47p.Mantlemetasomatism

Abstract: he meta-analysis of about 13,000 analyses of scandium content in garnet grains shows that, below the spinel-garnet transition, this phase carries about three-quarters of the Sc budget of the mantle, indicating its control on Sc mobility. The Sc content of garnets in mafic rocks is low, due to a dilution effect resulting from their high modal content in garnet. Garnets from ultramafic rocks exhibit a wider range of Sc concentrations. We assess the relative influence of thermobarometry, crystal chemistry and fluid-related events on the distribution of Sc in garnet from such rocks to improve the tracking of geochemical processes in the mantle. Pressure and temperature of equilibration in the mantle are second-order factors influencing the Sc content of garnet, while crystal-chemistry, in particular and , is the main parameter controlling the compatibility of Sc. Scandium is incorporated in both X and Y sites of Cr-Ca-rich garnets, resulting in a behaviour intermediate between rare-earth elements, incorporated in the X site, and trivalent transition elements, occupying the Y site. This affinity for both sites results in a mild compatibility of Sc in the garnet stability field of the mantle; hence Sc concentration in garnet increases with melt extraction and can be reduced by silicate-melt metasomatism. In contrast, metasomatism by volatile-rich fluids increases the Sc concentration in garnet. The control of garnet on the compatibility of Sc in deep lithospheric rocks demonstrates the potential of using Sc to track the conditions of formation of magmas and their residual rocks, as well as the origin and nature of metasomatic fluids.
DS201806-1225
2018
Griffin, W.L.Griffin, W.L., Huang, J-X., Thomassot, E., Gain, S.E.M., Toledo, V., O'Reilley, S.Y.Super reducing conditions in ancient and modern volcanic systems: sources and behaviour of carbon-rich fluids in the lithospheric mantle. Mt. Carmel moissaniteMineralogy and Petrology, in press available, 14p.Europe, Israelmetasomatism

Abstract: Oxygen fugacity (fO2) is a key parameter of Earth’s mantle, because it controls the speciation of the fluids migrating at depth; a major question is whether the sublithospheric mantle is metal-saturated, keeping fO2 near the Iron-Wustite (IW) buffer reaction. Cretaceous basaltic pyroclastic rocks on Mt. Carmel, Israel erupted in an intraplate environment with a thin, hot lithosphere. They contain abundant aggregates of hopper-shaped crystals of Ti-rich corundum, which have trapped melts with phenocryst assemblages (Ti2O3, SiC, TiC, silicides, native V) requiring extremely low fO2. These assemblages are interpreted to reflect interaction between basaltic melts and mantle-derived fluids dominated by CH4 + H2. Similar highly reduced assemblages are found associated with volcanism in a range of tectonic situations including subduction zones, major continental collisions, intraplate settings, craton margins and the cratons sampled by kimberlites. This distribution, and the worldwide similarity of ?13C in mantle-derived SiC and associated diamonds, suggest a widespread process, involving similar sources and independent of tectonic setting. We suggest that the common factor is the ascent of abiotic (CH4 + H2) fluids from the sublithospheric mantle; this would imply that much of the mantle is metal-saturated, consistent with observations of metallic inclusions in sublithospheric diamonds (e.g. Smith et al. 2016). Such fluids, perhaps carried in rapidly ascending deep-seated magmas, could penetrate high up into a depleted cratonic root, establishing the observed trend of decreasing fO2 with depth (e.g. Yaxley et al. in Lithos 140:142-151, 2012). However, repeated metasomatism (associated with the intrusion of silicate melts) will raise the FeO content near the base of the craton over time, developing a carapace of oxidizing material that would prevent the rise of CH4-rich fluids into higher levels of the subcontinental lithospheric mantle (SCLM). Oxidation of these fluids would release CO2 and H2O to drive metasomatism and low-degree melting both in the carapace and higher in the SCLM. This model can explain the genesis of cratonic diamonds from both reduced and oxidized fluids, the existence of SiC as inclusions in diamonds, and the abundance of SiC in some kimberlites. It should encourage further study of the fine fractions of heavy-mineral concentrates from all types of explosive volcanism.
DS201806-1243
2018
Griffin, W.L.Rezvukhin, D.I., Malkovets, V.G., Sharygin, I.S., Tretiakova, I.G., Griffin, W.L., O'Reilly, S.Y.Inclusions of crichtonite group minerals in Cr-pyropes from the Internationalnaya kimberlite pipe, Siberian craton: crystal chemistry, parageneses and relationships to mantle metasomatism.Lithos, Vol. 308, 1, pp. 181-195.Russiadeposit - International

Abstract: Cr-pyrope xenocrysts and associated inclusions of crichtonite-group minerals from the Internatsionalnaya kimberlite pipe were studied to provide new insights into processes in the lithospheric mantle beneath the Mirny kimberlite field, Siberian craton. Pyropes are predominantly of lherzolitic paragenesis (Cr2O3 2-6?wt%) and have trace-element spectra typical for garnets from fertile mantle (gradual increase in chondrite-normalized values from LREE to MREE-HREE). Crichtonite-group minerals commonly occur as monomineralic elongated inclusions, mostly in association with rutile, Mg-ilmenite and Cr-spinel within individual grains of pyrope. Sample INT-266 hosts intergrowth of crichtonite-group mineral and Cl-apatite, while sample INT-324 contains polymineralic apatite- and dolomite-bearing assemblages. Crichtonite-group minerals are Al-rich (1.1-4.5?wt% Al2O3), moderately Zr-enriched (1.3-4.3?wt% ZrO2), and are Ca-, Sr-, and occasionally Ba-dominant in terms of A-site occupancy; they also contain significant amounts of Na and LREE. T-estimates and chemical composition of Cr-pyropes imply that samples represent relatively low-T peridotite assemblages with ambient T ranging from 720 to 820°?. Projected onto the 35?mW/m2 cratonic paleogeotherm for the Mirny kimberlite field (Griffin et al., 1999b. Tectonophysics 310, 1-35), temperature estimates yield a P range of ~34-42?kbar (~110-130?km), which corresponds to a mantle domain in the uppermost part of the diamond stability field. The presence of crichtonite-group minerals in Cr-pyropes has petrological and geochemical implications as evidence for metasomatic enrichment of some incompatible elements in the lithospheric mantle beneath the Mirny kimberlite field. The genesis of Cr-pyropes with inclusions of crichtonite-group minerals is attributed to the percolation of Ca-Sr-Na-LREE-Zr-bearing carbonate-silicate metasomatic agents through Mg- and Cr-rich depleted peridotite protoliths. The findings of several potentially new members of the crichtonite group as inclusions in garnet extend existing knowledge on the compositions and occurrences of exotic titanates stable in the lithospheric mantle.
DS201808-1749
2018
Griffin, W.L.Griffin, W.L., Huang, J-X., Thomassot, E., Gain, S.E.M., Toledo, V., O'Reilly, S.Y.Super-reducing conditions in ancient and modern volcanic systems: sources and behaviour of carbon-rich fluids in the lithospheric mantle ( Mt. Carmel).Mineralogy and Petrology, doi.org/10.1007/s00710-018-0575-x 14p.Mantlemoissanite
DS201808-1788
2018
Griffin, W.L.Shatsky, V.S., Malkovets, V.G., Belousova, E.A., Tretiakova, I.G., Griffin, W.L., Ragozin, A.L., Wang, Q., Gibsher, A.A., O'Reilly, S.Y.Multi stage modification of Paleoarchean crust beneath the Anabar tectonic provnce ( Siberian craton).Precambrian Research, Vol. 305, pp. 125-144.Russiatectonics

Abstract: According to present views, the crustal terranes of the Anabar province of the Siberian craton were initially independent blocks, separated from the convecting mantle at 3.1 (Daldyn terrane), 2.9 (Magan terrane) and 2.5?Ga (Markha terrane) (Rosen, 2003, 2004; Rosen et al., 1994, 2005, 2009). Previous studies of zircons in a suite of crustal xenoliths from kimberlite pipes of the Markha terrane concluded that the evolution of the crust of the Markha terrane is very similar to that of the Daldyn terrane. To test this conclusion we present results of U-Pb and Hf-isotope studies on zircons in crustal xenoliths from the Zapolyarnaya kimberlite pipe (Upper Muna kimberlite field), located within the Daldyn terrane, and the Botuobinskaya pipe (Nakyn kimberlite field) in the center of the Markha terrane. The data on xenoliths from the Botuobinskaya kimberlite pipe record tectonothermal events at 2.94, 2.8, 2.7 and 2?Ga. The event at 2?Ga caused Pb loss in zircons from a mafic granulite. U-Pb dating of zircons from the Zapolyarnaya pipe gives an age of 2.7?Ga. All zircons from the studied crustal xenoliths have Archean Hf model ages ranging from 3.65 to 3.11?Ga. This relatively narrow range suggests that reworking of the ancient crust beneath the Nakyn and Upper Muna kimberlite fields was minor, compared with the Daldyn and Alakit-Markha fields (Shatsky et al., 2016). This study, when combined with dating of detrital zircons, implies that tectonic-thermal events at 2.9 -2.85, 2.75 -2.7 and 2.0 -1.95?Ga occurred everywhere on the Anabar tectonic province, and could reflect the upwelling of superplumes at 2.9, 2.7 and 2?Ga. The presence of the same tectonic-thermal events in the Daldyn and Markha terranes (Rosen et al., 2006a,b) supports the conclusion that the identification of the Markha terrane as a separate unit is not valid.
DS201809-2006
2018
Griffin, W.L.Castillo-Oliver, M., Giuliani, A., Griffin, W.L., O'Reilly, S.Y.Characterisation of primary and secondary carbonates in hypabyssal kimberlites: an integrated compositional and Sr-isotopic approach. Mineralogy and Petrology, doi.org/10.1007/s00710-018-0626-3 13p.Africa, South Africa, Australia, Europe, Finland, Canada, Northwest Territoriesdeposit - Wesselton, De Beers, Bultfontein, Benfontein, Jagersfontein, Cullinan, Melita, Pipe 1, Grizzley, Koala

Abstract: Carbonates in fresh hypabyssal kimberlites worldwide have been studied to understand their origin [i.e. primary magmatic (high T) versus deuteric (‘low T’) versus hydrothermal/alteration (‘low T’)] and identify optimal strategies for petrogenetic studies of kimberlitic carbonates. The approach presented here integrates detailed textural characterisation, cathodoluminescence (CL) imaging, in situ major- and trace-element analysis, as well as in situ Sr-isotope analysis. The results reveal a wide textural diversity. Calcite occurs as fine-grained groundmass, larger laths, segregations, veins or as a late crystallising phase, replacing olivine or early carbonates. Different generations of carbonates commonly coexist in the same kimberlite, each one defined by a characteristic texture, CL response and composition (e.g., variable Sr and Ba concentrations). In situ Sr isotope analysis revealed a magmatic signature for most of the carbonates, based on comparable 87Sr/86Sr values between these carbonates and the coexisting perovskite, a robust magmatic phase. However, this study also shows that in situ Sr isotope analysis not always allow distinction between primary (i.e., magmatic) and texturally secondary carbonates within the same sample. Carbonates with a clear secondary origin (e.g., late-stage veins) occasionally show the same moderately depleted 87Sr/86Sr ratios of primary carbonates and coexisting perovskite (e.g., calcite laths-shaped crystals with 87Sr/86Sr values identical within uncertainty to those of vein calcite in the De Beers kimberlite). This complexity emphasises the necessity of integrating detailed petrography, geochemical and in situ Sr isotopic analyses for an accurate interpretation of carbonate petrogenesis in kimberlites. Therefore, the complex petrogenesis of carbonates demonstrated here not only highlights the compositional variability of kimberlites, but also raises concerns about the use of bulk-carbonate C-O isotope studies to characterise the parental melt compositions. Conversely, our integrated textural and in situ study successfully identifies the most appropriate (i.e. primary) carbonates for providing constraints on the isotopic parameters of parental kimberlite magmas.
DS201810-2323
2018
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Huang, J.X., Belousova, E.A., Toledo, V., O'Reilly, S.Y.Permian to quaternary magmatism beneath the Mt. Carmel area, Israel: zircons from volcanic rocks and associated alluvial deposits.Lithos, Vol. 314-315, pp. 307-322.Europe, Israel zircons

Abstract: Xenocrystic zircons from Cretaceous pyroclastic vents on Mt. Carmel, N. Israel, document two major periods of earlier mafic magmatism: Permo-Triassic (285-220?Ma) and Jurassic (200-160?Ma). Related alluvial deposits also contain these zircon populations. However, most alluvial zircons are Cretaceous (118-80?Ma) or younger, derived from Miocene to Pliocene volcanic episodes. The Permo-Triassic-Jurassic zircons are typically large and glassy; they have irregular shapes and a wide variety of internal zoning patterns. They appear to have grown in the interstitial spaces of coarse-grained rocks; many show evidence of recrystallization, including brecciation and rehealing by chemically similar zircon. Grains with relict igneous zoning have mantle-like ?18O (5.5?±?1.0‰), but brecciation leads to lower values (mean 4.8‰, down to 3.1‰). Hf-isotope compositions lie midway between the Chondritic Uniform Reservoir (CHUR) and Depleted Mantle (DM) reservoirs; Hf model ages suggest that the source region separated from DM in Neoproterozoic time (1500-1000?Ma). Most Cretaceous zircons have 176Hf/177Hf similar to those of the older zircons, suggesting recrystallization and/or Pb loss from older zircons in the Cretaceous thermal event. The Permo-Jurassic zircons show trace-element characteristics similar to those crystallized from plume-related magmas (Iceland, Hawaii). Calculated melts in equilibrium with them are characterized by strong depletion in LREE and P, large positive Ce anomalies, variable Ti anomalies, and high and variable Nb, Ta, Th and U, consistent with the fractionation of monazite, zircon, apatite and Ti-bearing phases. We suggest that these coarse-grained zircons crystallized from late differentiates of mafic magmas, ponded near the crust-mantle boundary (ca 30?km depth), and were reworked repeatedly by successively younger igneous/metasomatic fluids. The zircon data support a published model that locates a fossil Neoproterozoic plume head beneath much of the Arabia-Levant region, which has been intermittently melted to generate the volcanic rocks of the region. The Cretaceous magmas carry mantle xenoliths derived from depths up to 90?km, providing a minimum depth for the possible plume head. Post-Cretaceous magmatism, as recorded in detrital zircons, shows distinct peaks at 30?Ma, 13?Ma, 11.4?±?0.1?Ma (a major peak; n?=?15), 9-10?Ma and 4?Ma, representing the Lower and Cover Basalts in the area. Some of these younger magmas tapped the same mantle source as the Permian-Jurassic magmatism, but many young zircons have Hf-isotope compositions extending up to DM values, suggesting derivation of magmas from deeper, more juvenile sources.
DS201810-2324
2018
Griffin, W.L.Griffin, W.L., Howell, D., Gonzalez-Jimenez, J.M., Xiong, Q.., O'Reilly, S.Y.Comment: Ultra high pressure and ultra reduced minerals in ophiolites may form by lightning strikes. Super Reduced Minerals SURGeochemical Perspectives Letters, Vol. 7, pp. 1-2.Mantlemoissanite

Abstract: Ballhaus et al. (2017) use electric-discharge experiments to argue that lightning strikes could produce ultra-high pressure (UHP) and super-reduced (SuR) phases "identical to those found in 'high-pressure' ophiolites" and that thus there is "not sufficient evidence to challenge long-established models of ophiolite genesis", specifically for the UHP processing of Tibetan ophiolites. However, the authors produced no evidence for UHP phases in their experiments. There are pertinent observations, relevant to the authors’ assertions, in the literature regarding the relationship between the UHP and SuR assemblages in the Tibetan peridotites. Their conclusions are not consistent with this evidence.
DS201810-2349
2018
Griffin, W.L.Lu, J., Griffin, W.L., Tilhac, R., Xiong, Q., Zheng, J., O'Reilly, S.Y.Tracking deep lithospheric events with garnet-websterite xenoliths from southeastern Australia.Journal of Petrology, Vol. 59, 5, pp. 901-903.Australiabasanite

Abstract: Pyroxenites provide important information on mantle heterogeneity and can be used to trace mantle evolution. New major and trace element and Sr-, Nd-, and Hf-isotope analyses of minerals and whole-rock samples of garnet websterites entrained in basanite tuffs in Bullenmerri and Gnotuk maars, southeastern Australia, are here combined with detailed petrographic observations to constrain the sources and genesis of the pyroxenites, and to trace the dynamic evolution of the lithospheric mantle. Most garnet websterites have high MgO and Cr2O3 contents, relatively flat light rare earth element (LREE) patterns ([La/Nd]CN?=?0•77-2•22) and ocean island basalt-like Sr-, Nd-, and Hf-isotope compositions [87Sr/86Sr?=?0•70412-0•70657; ?Nd(t)?=?-0•32 to +4•46; ?Hf(t)=+1•69 to +18•6] in clinopyroxenes. Some samples show subduction-related signatures with strong enrichments in large ion lithophile elements and LREE, and negative anomalies in high field strength elements, as well as high 87Sr/86Sr (up to 0•709), and decoupled Hf- and Nd-isotope compositions [?Nd(t)?=?-3•28; ?Hf(t) =?+11•6). These data suggest that the garnet pyroxenites represent early crystallization products of mafic melts derived from a convective mantle wedge. Hf model ages and Sm-Nd mineral isochrons suggest that these pyroxenites record at least two stages of evolution. The initial formation stage corresponds to the Paleozoic subduction of the proto-Pacific plate beneath southeastern Australia, which generated hydrous tholeiitic melts that crystallized clinopyroxene-dominated pyroxenites at ?1420-1450°C and ?75?km depth in the mantle wedge. The second stage corresponds to Eocene (c. 40?Ma) back-arc lithospheric extension, which led to uplift of the former mantle-wedge domain to 40-60?km depths, and subsequent cooling to the ambient geotherm (?950-1100°C). Extensive exsolution and recrystallization of garnet and orthopyroxene (±?ilmenite) from clinopyroxene megacrysts accompanied this stage. The timing of these mantle events coincides with vertical tectonism in the overlying crust.
DS201810-2360
2018
Griffin, W.L.Nasdala, L., Corfu, F., Schoene, B., Tapster, S.R., Wall, C.J., Schmitz, M.D., Ovtcharova, M., Schaltegger, U., Kennedy, A.K., Kronz, A., Reiners, P.W., Yang, Y-H., Wu, F-Y., Gain, S.E.M., Griffin, W.L., Szymanowski, D., Chanmuang, C., Ende, N.M., ValleyGZ7 and GZ8 - two zircon reference materials for SIMS U-Pb geochronology.Geostandards and Geoanalytical Research, http://orchid.org/0000-0002-2701-4635 80p.Asia, Sri Lankageochronology

Abstract: Here we document a detailed characterization of two zircon gemstones, GZ7 and GZ8. Both stones had the same mass at 19.2 carats (3.84 g) each; both came from placer deposits in the Ratnapura district, Sri Lanka. The U-Pb data are in both cases concordant within the uncertainties of decay constants and yield weighted mean ²??Pb/²³?U ages (95% confidence uncertainty) of 530.26 Ma ± 0.05 Ma (GZ7) and 543.92 Ma ± 0.06 Ma (GZ8). Neither GZ7 nor GZ8 have been subjected to any gem enhancement by heating. Structure?related parameters correspond well with the calculated alpha doses of 1.48 × 10¹? g?¹ (GZ7) and 2.53 × 10¹? g?¹ (GZ8), respectively, and the (U-Th)/He ages of 438 Ma ± 3 Ma (2s) for GZ7 and 426 Ma ± 9 Ma (2s) for GZ8 are typical of unheated zircon from Sri Lanka. The mean U concentrations are 680 ?g g?¹ (GZ7) and 1305 ?g g?¹ (GZ8). The two zircon samples are proposed as reference materials for SIMS (secondary ion mass spectrometry) U-Pb geochronology. In addition, GZ7 (Ti concentration 25.08 ?g g?¹ ± 0.18 ?g g?¹; 95% confidence uncertainty) may prove useful as reference material for Ti?in?zircon temperature estimates.
DS201811-2622
2018
Griffin, W.L.Zedgenizov, D.A., Ragozin, A.L., Shatsky, V.S., Griffin, W.L.Diamond formation during metasomatism of mantle eclogite by chloride-carbonate melt.Contributions to Mineralogy and Petrology, Vol. 173, 16p. Doi.org/10.1007/s00410-018-1513-yRussiadeposit - Udachnaya

Abstract: A xenolith of bimineralic eclogite from the Udachnaya kimberlite pipe provides a snapshot of interaction between mantle rocks and diamond-forming fluids/melts. The major-element composition of the eclogite is similar to that of N-MORB and/or oceanic gabbros, but its trace-element pattern shows the effects of mantle metasomatism, which resulted in diamond formation. The diamonds are clustered in alteration veins that crosscut primary garnet and clinopyroxene. The diamonds contain microinclusions of a fluid/melt dominated by carbonate and KCl. Compared to the worldwide dataset, the microinclusions in these diamonds fall in middle of the range between saline fluids and low-Mg carbonatitic melts. The fluid/melt acted as a metasomatic agent that percolated through ancient eclogitic rocks stored in the mantle. This interaction is consistent with calculated partition coefficients between the rock-forming minerals and diamond-forming fluid/melt, which are similar to experimentally-determined values. Some differences between the calculated and experimental values may be due to the low contents of water and silicates in the chloride-carbonate melt observed in this study, and in particular its high contents of K and LILE. The lack of nitrogen aggregation in the diamonds implies that the diamond-forming metasomatism took place shortly before the eruption of the kimberlite, and that the microinclusions thus represent saline carbonate-rich fluids circulating in the basement of lithospheric mantle (150-170 km depth).
DS201812-2844
2018
Griffin, W.L.Ma, Q., Xu, Y-G., Deng, Y,m Zhengm J-P., Sur, M., Griffin, W.L., Xia, B., Yan Wang, C.Similar crust beneath disrupted and intact cratons: arguments against lower crust delamination as a decratonization trigger. North China cratonTectonophysics, in press available 31p.Chinacraton

Abstract: The continental lithosphere is not forever; some cratons have lost their original roots during the course of their evolution. Yet, it is not clear whether gravitational instability of dense lower crust is the primary driver of decratonization. This is addressed here with emphasis being placed on the North China Craton (NCC), because it represents one of the best examples of craton-root disruption in the world, and a place where models can be tested. If lower-crustal delamination was the trigger for decratonization, we would expect a clear contrast in crustal structure and composition between disturbed (rootless) and intact cratons. However, the eastern (disturbed) and western (intact) parts of the NCC show virtually identical physical structure and composition (a thin mafic lower crust and a predominantly intermediate composition overall) although the crust in the disturbed part is thinner than in the intact craton. This suggests that delamination of the lower crust was not a viable mechanism of craton-root disruption in the NCC case. Indeed, the crust beneath the NCC largely resembles those of stable Archean cratons worldwide. Therefore the delamination, if it occurred, may have taken place much earlier (Archean) than previously thought, rather than in the Mesozoic. Delamination may have been a common phenomenon in the early evolution of cratons, probably due to relatively higher mantle temperatures in the Archean Eon.
DS201902-0275
2018
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Bindi, L., Toledo, V., Camara, F., Saunders, M., O'Reilly, S.Y.Carmeltazite, ZrAl2Ti4011, a new mineral trapped in corundum from volcanic rocks of Mt Carmel, northern Israel.Minerals ( mdpi.com), Vol. 8, 12, 11p. PdfEurope, Israelmineralogy

Abstract: The new mineral species carmeltazite, ideally ZrAl2Ti4O11, was discovered in pockets of trapped melt interstitial to, or included in, corundum xenocrysts from the Cretaceous Mt Carmel volcanics of northern Israel, associated with corundum, tistarite, anorthite, osbornite, an unnamed REE (Rare Earth Element) phase, in a Ca-Mg-Al-Si-O glass. In reflected light, carmeltazite is weakly to moderately bireflectant and weakly pleochroic from dark brown to dark green. Internal reflections are absent. Under crossed polars, the mineral is anisotropic, without characteristic rotation tints. Reflectance values for the four COM wavelengths (Rmin, Rmax (%) (? in nm)) are: 21.8, 22.9 (471.1); 21.0, 21.6 (548.3), 19.9, 20.7 (586.6); and 18.5, 19.8 (652.3). Electron microprobe analysis (average of eight spot analyses) gave, on the basis of 11 oxygen atoms per formula unit and assuming all Ti and Sc as trivalent, the chemical formula (Ti3+3.60Al1.89Zr1.04Mg0.24Si0.13Sc0.06Ca0.05Y0.02Hf0.01)?=7.04O11. The simplified formula is ZrAl2Ti4O11, which requires ZrO2 24.03, Al2O3 19.88, and Ti2O3 56.09, totaling 100.00 wt %. The main diffraction lines, corresponding to multiple hkl indices, are (d in Å (relative visual intensity)): 5.04 (65), 4.09 (60), 2.961 (100), 2.885 (40), and 2.047 (60). The crystal structure study revealed carmeltazite to be orthorhombic, space group Pnma, with unit-cell parameters a = 14.0951 (9), b = 5.8123 (4), c = 10.0848 (7) Å, V = 826.2 (1) Å3, and Z = 4. The crystal structure was refined to a final R1 = 0.0216 for 1165 observed reflections with Fo > 4?(Fo). Carmeltazite exhibits a structural arrangement similar to that observed in a defective spinel structure. The name carmeltazite derives from Mt Carmel (“CARMEL”) and from the dominant metals present in the mineral, i.e., Titanium, Aluminum and Zirconium (“TAZ”). The mineral and its name have been approved by the IMA Commission on New Minerals, Nomenclature and Classification (2018-103).
DS201903-0514
2019
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Huang, J-X., Saunders, M., Shaw, J., Toledo, V., O'Reilly, S.Y.A terrestrial magmatic hibonite-grossite-vanadium assemblage: desilication and extreme reduction in a volcanic plumbing system, Mount Carmel, Israel.American Mineralogist, Vol. 104, pp. 207-219.Europe, Israelmelting

Abstract: Hibonite (CaAl12O19) is a constituent of some refractory calcium-aluminum inclusions (CAIs) in carbonaceous meteorites, commonly accompanied by grossite (CaAl4O7) and spinel. These phases are usually interpreted as having condensed, or crystallized from silicate melts, early in the evolution of the solar nebula. Both Ca-Al oxides are commonly found on Earth, but as products of high-temperature metamorphism of pelitic carbonate rocks. We report here a unique occurrence of magmatic hibonitegrossite-spinel assemblages, crystallized from Ca-Al-rich silicate melts under conditions [high-temperature, very low oxygen fugacity (fO2)] comparable to those of their meteoritic counterparts. Ejecta from Cretaceous pyroclastic deposits on Mt Carmel, N. Israel, include aggregates of hopper/skeletal Ti-rich corundum, which have trapped melts that crystallized at fO2 extending from 7 log units below the iron-wustite buffer (?IW = -7; SiC, Ti2O3, Fe-Ti silicide melts) to ?IW ? -9 (native V, TiC, and TiN). The assemblage hibonite + grossite + spinel + TiN first crystallized late in the evolution of the melt pockets; this hibonite contains percentage levels of Zr, Ti, and REE that reflect the concentration of incompatible elements in the residual melts as corundum continued to crystallize. A still later stage appears to be represented by coarse-grained (centimeter-size crystals) ejecta that show the crystallization sequence: corundum + Liq ? (low-REE) hibonite ? grossite + spinel ± krotite ? Ca4Al6F2O12 + fluorite. V0 appears as spheroidal droplets, with balls up to millimeter size and spectacular dendritic intergrowths, included in hibonite, grossite, and spinel. Texturally late V0 averages 12 wt% Al and 2 wt% Mn. Spinels contain 10-16 wt% V in V0-free samples, and <0.5 wt% V in samples with abundant V 0. Ongoing paragenetic studies suggest that the fO2 evolution of the Mt Carmel magmatic system reflects the interaction between OIB-type mafic magmas and mantle-derived CH4+H2 fluids near the crust-mantle boundary. Temperatures estimated by comparison with 1 atm phase-equilibrium studies range from ca. 1500 °C down to 1200-1150 °C. When fO2 reached ca. ?IW = -7, the immiscible segregation of Fe,Ti-silicide melts and the crystallization of SiC and TiC effectively desilicated the magma, leading to supersaturation in Al2O3 and the rapid crystallization of corundum, preceding the development of the hibonite-bearing assemblages. Reports of Ti-rich corundum and SiC from other areas of explosive volcanism suggest that these phenomena may be more widespread than presently realized, and the hibonite-grossite assemblage may serve as another indicator to track such activity. This is the first reported terrestrial occurrence of krotite (CaAl2O4), and of at least two unknown Zr-Ti oxides.
DS201905-1033
2019
Griffin, W.L.Giuliani, A., Martin, L.A.J., Soltys,A., Griffin, W.L.Mantle like oxygen isotopes in kimberlites determined by in situ SIMS analyses of zoned olivine.Geochimica et Cosmochimica Acta, in press available, 19p.Africa, South Africa, Canada, South America, Brazildeposit - Lac de Gras, Paranaiba

Abstract: Kimberlites are the deepest melts produced on Earth that are erupted at the surface and can therefore provide unique insights into the composition and evolution of the mantle. Radiogenic isotopes provide ambiguous evidence for the occurrence of recycled crustal material in kimberlite sources. Oxygen isotopes can fractionate significantly only in the shallow crust, and thus represent a powerful tracer of subducted material in the sources of kimberlite. To constrain the oxygen isotope composition of kimberlite melts, we have examined olivine grains in eleven Cretaceous to Eocene archetypal kimberlites from southern Africa, Lac de Gras (Canada) and Alto Paranaiba (Brazil), which exhibit radiogenic isotope evidence for recycled crustal material in their sources including highly radiogenic Pb isotopes and Nd-Hf isotope compositions deviating below the mantle array. Olivine grains are commonly zoned between a mantle-derived xenocrystic core and one or more magmatic overgrowths, i.e. occasional internal zones, ubiquitous rims and rare rinds (moving outward from the core). The oxygen isotope composition of different olivine zones was determined in situ within separated olivine grains by secondary ion mass spectrometry (SIMS) after point selection using back-scattered electron (BSE) images combined with major and minor element analyses. With the exception of a few cores, the ?18O values of different olivine zones do not deviate from typical mantle olivine values of 5.18?±?0.28‰ (Mattey et al., 1994). There are no correlations between oxygen isotopes and major/minor element compositions for internal zones and rims from individual localities or in the entire dataset. This indicates that the oxygen isotope composition of kimberlite melts is not affected by melt differentiation to the point of olivine rim crystallisation. However, olivine rinds from the Koala kimberlite (Canada) display an inverse correlation between ?18O and Mn-Ca concentrations, with ?18O values extending below the mantle range, which is probably due to carbonate fractionation, CO2 degassing and/or assimilation of serpentine-rich material after kimberlite emplacement in the upper crust. The mantle-like ?18O composition of olivine internal zones and rims suggests that assimilation of mantle material and liberation of a CO2-rich phase during ascent in the mantle do not significantly modify the original ?18O signature of kimberlite melts. Modelling of oxygen isotope fractionation shows that up to 15 wt% of CO2 can be lost by kimberlites en route to the upper crust. Our results combined with mass balance calculations indicate that only a limited amount (<5-10 wt%) of recycled crustal material could occur in the source of kimberlites from southern Africa, Lac de Gras and Alto Paranaiba, or that the recycled material had an oxygen isotope composition similar to the mantle.
DS201906-1276
2019
Griffin, W.L.Bindi, L., Camara, F., Griffin, W.L., Huang, J-X., Gain, S.E.M., Toledo, V., O'Reilly, S.Y.Discovery of the first natural hydride. Mt. CarmelAmerican Mineralogist, Vol. 104, pp. 611-614.Europe, Israelcrystallography

Abstract: Although hydrogen is the most abundant element in the solar system, the mechanisms of exchange of this element between the deep interior and surface of Earth are still uncertain. Hydrogen has profound effects on properties and processes on microscopic-to-global scales. Here we report the discovery of the first hydride (VH2) ever reported in nature. This phase has been found in the ejecta of Cretaceous pyroclastic volcanoes on Mt Carmel, N. Israel, which include abundant xenoliths containing highly reduced mineral assemblages. These xenoliths were sampled by their host magmas at different stages of their evolution but are not genetically related to them. The xenoliths are interpreted as the products of extended interaction between originally mafic magmas and CH4+H2 fluids, derived from a deeper, metal-saturated mantle. The last stages of melt evolution are recorded by coarse-grained aggregates of hibonite (CaAl12O19) + grossite (CaAl4O7) + V-rich spinels ± spheroidal to dendritic inclusions of metallic vanadium (V0), apparently trapped as immiscible metallic melts. The presence of V0 implies low oxygen fugacities and suggests crystallization of the aggregates in a hydrogen-rich atmosphere. The presence of such reducing conditions in the upper mantle has major implications for the transport of carbon, hydrogen and other volatile species from the deep mantle to the surface.
DS201906-1293
2019
Griffin, W.L.Gain, S.E.M., Greau, Y., Henry, H., Belousova, E., Dainis, I., Griffin, W.L., O'Reilly, S.Y.Mud Tank zircon: long term evaluation of a reference material for U-Pb dating, Hf-isotope analysis and trace element analysis. ( Carbonatite)Geostandards and Geoanalytical Research, in press available, 16p.Australiadeposit - Mud Tank

Abstract: Zircon megacrysts from the Mud Tank carbonatite, Australia, are being used in many laboratories as a reference material for LA?ICP?MS U?Pb dating and trace element measurement, and LA?MC?ICP?MS determination of Hf isotopes. We summarise a database of > 10000 analyses of Mud Tank zircon (MTZ), collected from 2000 to 2018 during its use as a secondary reference material for simultaneous U?Pb and trace element analysis, and for Hf?isotope analysis. Trace element mass fractions are highest in dark red?brown stones and lowest in colourless and gem?quality ones. Individual unzoned grains can be chemically homogeneous, while significant variations in trace element mass fraction are associated with oscillatory zoning. Chondrite?normalised trace element patterns are essentially parallel over large mass fraction ranges. A Concordia age of 731.0 ± 0.2 Ma (2s, n = 2272) is taken as the age of crystallisation. Some grains show lower concordant to mildly discordant ages, probably reflecting minor Pb loss associated with cooling and the Alice Springs Orogeny (450-300 Ma). Our weighted mean 176Hf/177Hf is 0.282523 ± 10 (2s, n = 9350); the uncertainties on this ratio reflect some heterogeneity, mainly between grains. A few analyses suggest that colourless grains have generally lower 176Hf/177Hf. MTZ is a useful secondary reference material for U?Pb and Hf?isotope analysis, but individual grains need to be carefully selected using CL imaging and tested for homogeneity, and ideally should be standardised by solution analysis.
DS201907-1547
2019
Griffin, W.L.Griffin, W.L., O'Reilly, S.Y.Making and unmaking continental mantle: geochemical and geophysical perspectives.Acta Geologica Sinica, Vol. 93, 1, pp. 249-250.Mantlegeochemistry

Abstract: Earth Scientists have two ways of examining and mapping the structure and composition of the subcontinental lithospheric mantle (SCLM): geophysical surveys, and studies of mantle samples from volcanic rocks or exposed terranes. Interpretation of both types of data requires an understanding of some basic strengths and limitations of each approach.
DS201910-2249
2019
Griffin, W.L.Chasse, M., Blanchard, M., Cabareta, D., Juhin, A., Vantelon, D., Griffin, W.L., O'Reilly, S.Y., Calas, G.Deciphering molecular-scale mechanisms covering scandium dynamics in the critical zone. Goldschmidt2019, in press available, 71 ppt.Australialaterites

Abstract: Scandium is often considered as immobile during chemical weathering, based on its low solubility. In contrast to other conservative (i.e. relatively immobile) elements incorporated into accessory minerals resistant to weathering (e.g. zirconium, thorium or niobium), the scarcity of scandium minerals indicates that the processes accounting for scandium's immobilisation are distinctive. However, the evolution of scandium speciation during weathering is unknown, limiting the understanding of the processes controlling its dynamics in the critical zone. Exceptional scandium concentrations in east Australian laterites provide the possibility of unravelling these mechanisms. We follow scandium speciation through thick lateritic profiles (> 30 m) using a multiscale mineralogical and spectroscopic approach involving electron microprobe, laser-ablation--inductively coupled plasma mass spectrometry, selective leaching and X-ray absorption near-edge structure spectroscopy, complemented by mass-transfer calculations. We show that the initial reservoir of scandium contained in the parent rock is preserved under reducing conditions occurring in the lowest horizons of the profiles. The dissolution of scandium-bearing clinopyroxene generates smectitic clays that immobilise and concentrate scandium. It is subsequently trapped in the lateritic duricrust by goethite. Scandium mobilisation appears in this horizon and increases upward as a result of the dissolution of goethite, possibly assisted by dissolved organic matter, and the precipitation of hematite. Molecular-scale analyses demonstrate that changes in speciation govern scandium dynamics, with substitution in smectitic clays and adsorption on iron oxyhydroxides playing a crucial role in scandium immobility in the saprolite and lower lateritic duricrust. The higher affinity of scandium for goethite relative to hematite drives scandium mobilisation in the upper lateritic duricrust, leading to its concentration downward in the lower lateritic duricrust. These successive mechanisms illustrate how the unique complexity of the critical zone leads to scandium concentrations that may form new types of world-class scandium deposits. Comparison with conservative elements and with rare-earth elements, expected to have similar geochemical properties, emphasizes the unique behaviour of scandium in the critical zone. While scandium remains immobile during the early stages of weathering, intense and long-term alteration processes, observed in lateritic contexts, lead to scandium mobilisation. This study highlights the dependence of scandium mobility on weathering conditions.
DS201910-2258
2019
Griffin, W.L.Gain, S.E., Griffin, W.L., Saunders, M., Shaw, J.A., Toledo, V.A showcase of analytical techniques: native vanadium in hibonite and chromium in corundum: ultra-high contents under reducing conditions. Two posters Shefa Gems Microscopy and Microanalysis ( M&M)Co. Conference, Sept. 9, posters 1 p. eachEurope, Israeldeposit - Kishon

Abstract: The Microscopy and Microanalysis (M&M) conference in Portland Oregon, USA is one of the biggest microscopy conferences in the world and this year it hosted its largest meeting in history with over 3,300 participants, up to 20 parallel sessions and over 600 posters. The two posters were presented by Sarah E.M. Gain who is from the University of Western Australia where she trains and supports researchers in Microscopy, Characterisation and Microanalysis. Sarah discussed some of the unique gem material collected from Shefa Gems’ exploration activity in the Kishon Mid Reach and Rakefet Magmatic Complex, analysed using a range of microscopy and microanalysis techniques. She also discussed the scientific importance of this material.The first poster looked at hibonite (a Ca-Al-oxide) with inclusions of vanadium metal. The second poster looked at, Cr corundum (ruby), which is unusual due to the extremely high Cr levels and the inclusions of Cr metal.
DS201911-2544
2019
Griffin, W.L.Malkovets, V.G., Rezvukhin, D.I., Griffin, W.L., Tretiakova, I.G., Pearson, N.J., Gibsher, A.A., Belousova, E.A., Zedgenizov, D.A., O'Reilly, S.Y.Re-Os dating of sulfide inclusions in Cr-pyropes from the Upper Muna kimberlites.Goldschmidt2019, 1p. AbstractRussiadeposit - Upper Muna

Abstract: Archean cratons are underlain by highly depleted subcontinental lithospheric mantle (SCLM). However, there are extensive evidences that Archean SCLM has been extensively refertilized by metasomatic processes, with the addition of Fe, Ca, and Al to depleted protoliths. The distribution of sub-calcic Cr-rich garnets in the SCLM beneath the Siberian craton suggests (1) sub-calcic garnets and diamonds are metasomatic phases in the cratonic SCLM; (2) the distribution of both phases is laterally heterogeneous on relatively small scales and related to ancient structural controls [1]. Re-Os isotopic compositions of twenty six sulfide inclusions in lherzolitic Cr-pyropes from Upper Muna kimberlites have been determined by laser ablation MCICPMS. Most analysed sulfides (~92%) have very low Re/Os ratios (<0.07), and their Re-depletion ages (TRD) form three major peaks: 3.4-2.8, 2.2-1.8 and 1.4-1.2 Ga (±0.03 Ga, mean 2s analytical uncertainty). One sulfide give the oldest TRD age at 4 Ga. Our data suggest that refertilization of the highly depleted SCLM and the introduction of Cr-pyrope garnet occurred in several episodes. The oldest age of ca 4 Ga indicate on the beginning of the formation of the depleted SCLM of the Siberian Craton in Hadean time [2].
DS202002-0219
2020
Griffin, W.L.Tilhac, R., Oliveira, B., Griffin, W.L., O'Reilly, S.Y., Schaefer, B.F., Alard, O., Ceuleneer, G., Afonso, J.C., Gregoire, M.Reworking of old continental lithosphere: unradiogenic Os and decoupled Hf-Nd isotopes in sub-arc mantle pyroxenites.Lithos, Vol. 354-355, 19p. pdfEurope, Spainpyroxenites

Abstract: Mantle lithologies in orogenic massifs and xenoliths commonly display strikingly different Hf- and Nd-isotope compositions compared to oceanic basalts. While the presence of pyroxenites has long been suggested in the source region of mantle-derived magmas, very few studies have reported their combined HfNd isotope compositions. We here report the first LuHf data along with ReOs data and S concentrations on the Cabo Ortegal Complex, where the pyroxenite-rich Herbeira massif has been interpreted as remnants of a delaminated arc root. The pyroxenites, chromitites and their host harzburgites show a wide range of whole-rock 187Re/188Os and 187Os/188Os (0.16-1.44), indicating that Re was strongly mobilized, partly during hydrous retrograde metamorphism but mostly during supergene alteration that preferentially affected low-Mg#, low Cu/S pyroxenites. Samples that escaped this disturbance yield an isochron age of 838 ± 42 Ma, interpreted as the formation of Cabo Ortegal pyroxenites. Corresponding values of initial 187Os/188Os (0.111-0.117) are relatively unradiogenic, suggesting limited contributions of slab-derived Os to primitive arc melts such as those parental to these pyroxenites. This interpretation is consistent with radiogenic Os in arc lavas being mostly related to crustal assimilation. Paleoproterozoic to Archean Os model ages confirm that Cabo Ortegal pyroxenites record incipient volcanic arc magmatism on the continental margin of the Western African Craton, as notably documented by zircon UPb ages of 2.1 and 2.7 Ga. LuHf data collected on clinopyroxene and amphibole separates and whole-rock samples are characterized by uncorrelated 176Lu/177Hf and 176Hf/177Hf (0.2822-0.2855), decoupled from Nd-isotope compositions. This decoupling is ascribed to diffusional disequilibrium during melt-peridotite interaction, in good agreement with the results of percolation-diffusion models simulating the interaction of an arc melt with an ancient melt-depleted residue. These models notably show that HfNd isotopic decoupling such as recorded by Cabo Ortegal pyroxenites and peridotites (??Hf(i) up to +97) is enhanced during melt-peridotite interaction by slow diffusional re-equilibration and can be relatively insensitive to chromatographic fractionation. Finally, we discuss the hypothesis that arc-continent interaction may provide preferential conditions for such isotopic decoupling and propose that its ubiquitous recognition in peridotites reflects the recycling of sub-arc mantle domains derived from ancient, reworked SCLM.
DS202005-0725
2020
Griffin, W.L.Castillo-Oliver, M., Giuliani, A., Griffin, W.L., Drsydale, Rn.New constraints on the source, composition, and post-emplacement modification of kimberlites from in situ C-O-Sr-isotope analyses of carbonates from the Benfontein sills ( South Africa).Contributions to Mineralogy and Petrology, in press available, 21p. PdfAfrica, South Africadeposit - Benfontein

Abstract: Primary carbonates in kimberlites are the main CO2 carriers in kimberlites and thus can be used to constrain the original carbon and oxygen-isotope composition of kimberlite melts and their deep mantle sources. However, the contribution of syn- and post-emplacement processes to the modification of the C-O-isotope composition of kimberlites is yet to be fully constrained. This study aims to shed new light on this topic through a detailed textural, compositional (major and trace elements), and in situ C-O-Sr isotopic characterisation of carbonates in the Benfontein kimberlite sills (Kimberley, South Africa). Our multi-technique approach not only reveals the petrographic and geochemical complexity of carbonates in kimberlites in unprecedented detail, but also allows identification of the processes that led to their formation, including: (1) magmatic crystallisation of Sr-rich calcite laths and groundmass; (2) crystallisation of late groundmass calcite from hydrothermal fluids; and (3) variable degrees of crustal contamination in carbonate-rich diapirs and secondary veins. These diapirs most likely resulted from a residual C-O-H fluid or carbonate melt with contributions from methane-rich fluids from the Dwyka shale wall rock, leading to higher 87Sr/86Sr and ?18O, but lower ?13C values than in pristine magmatic calcite. Before coalescing into the diapiric segregations, these fluids/melts also variably entrained early formed calcite laths and groundmass phases. Comparison between in situ and bulk-carbonate analyses confirms that O isotopic analyses of bulk carbonates from kimberlite rocks are not representative of the original isotopic signature of the kimberlite magma, whereas bulk C-isotope compositions are similar to those of the pristine magmatic carbonates. Calcite laths and most groundmass grains at Benfontein preserve isotopic values (?18O?=?6-8‰ and ?13C?=???4 to ??6‰), similar to those of unaltered carbonatites worldwide, which, therefore, probably correspond to those of their parental melts. This narrow range suggests kimberlite derivation from a mantle source with little contribution from recycled crustal material unless the recycled material had isotopic composition indistinguishable from typical mantle values.
DS202007-1161
2020
Griffin, W.L.Lu, J., Tilhac, R., Griffin, W.L., Zheng, J.P., Xiong, Q., Oliveira, B., O'Reilly, S.Y.Lithospheric memory of subduction in mantle pyroxenite xenoliths from rift related basalts.Earth and Planetary Science Letters, Vol. 544, 116365 14p. PdfAustraliacarbonatite

Abstract: Petrological and geochemical studies have revealed the contribution of garnet pyroxenites in basalt petrogenesis. However, whether primary mantle melts are produced with such signature or acquired it subsequently remains somewhat controversial. We here integrate new major-, trace-element and Sr-Nd-Hf isotopic compositions of garnet pyroxenite xenoliths in Holocene alkali basalts from Lakes Bullenmerri and Gnotuk, Southeastern Australia, to relate their petrogenesis to mantle-wedge melt circulation and subsequent lithospheric evolution. Results show that the clinopyroxenites have lower MgO and Cr2O3 contents than the associated websterites, and range in compositions from depleted LREE patterns and highly radiogenic Nd and Hf isotopic signatures in relatively low-MgO samples (Type 1), to enriched REE patterns with negative HFSE anomalies, unradiogenic Nd and Hf isotopes, and extremely radiogenic Sr-isotopic ratios in samples with higher MgO (Type 2). Such compositional variabilities suggest that these pyroxenites represent segregates from melts derived from a recycled oceanic lithosphere with a potential contribution from pelagic sediments. Variable LREE contents and isotopic compositions between those of Type 1 and 2 clinopyroxenites are observed in amphibole-bearing samples (Type 3), which are interpreted as Type 1-like protoliths metasomatized by the basaltic and carbonatitic melts, possibly parental to Type 2 clinopyroxenites. The lithosphere beneath Southeastern Australia thus has received variable melt contributions from a heterogeneous mantle-wedge source, which notably includes a subducted oceanic slab package that has retained its integrity during subduction. On this basis, we suggest that the compositional heterogeneity and temporal evolution of the subsequent Southeastern Australian basaltic magmatism were probably affected by the presence of pyroxenite fragments in the basalt source and formed by the tectonic reactivation of this lithosphere during Cenozoic rifting. This interpretation is notably consistent with a trend of Nd-Pb isotopes towards EMII in Older Volcanic Provinces (OVP basalts) and limited Sr-Nd-Pb isotopic variations towards HIMU in the Newer Volcanic Provinces (NVP basalts, including the host lavas), which also exhibit low SiO2, high FeO and high CaO/Al2O3 commonly interpreted as due to pyroxenite contributions. Therefore, the identification of a subduction signature in these rift-related lavas attests to a "lithospheric memory" of earlier subduction episodes (as documented by the xenoliths), rather than a reflection of contemporaneous subduction tectonics.
DS202008-1422
2020
Griffin, W.L.McKensie, L., Kilgore, A.H., Peslier, A.D., Brandon, L.A., Schaffer, R.V., Graff, T.G., Agresti, D.G., O'Reilly, S.Y., Griffin, W.L., Pearson, D.G., Hangi, K., Shaulis, B.J.Metasomatic control of hydrogen contents in the layered cratonic mantle lithosphere sampled by Lac de Gras xenoliths in the central Slave craton, Canada.Geochimica et Cosmochimica Acta, in press available, doi.org/101016 /j.gca.2020.07.013 45p. PdfCanada, Northwest Territoriesdeposit - Lac de Gras

Abstract: Whether hydrogen incorporated in nominally anhydrous mantle minerals plays a role in the strength and longevity of the thick cratonic lithosphere is a matter of debate. In particular, the percolation of hydrogen-bearing melts and fluids could potentially add hydrogen to the mantle lithosphere, weaken its olivines (the dominant mineral in mantle peridotite), and cause delamination of the lithosphere's base. The influence of metasomatism on hydrogen contents of cratonic mantle minerals can be tested in mantle xenoliths from the Slave Craton (Canada) because they show extensive evidence for metasomatism of a layered cratonic mantle. Minerals from mantle xenoliths from the Diavik mine in the Lac de Gras kimberlite area located at the center of the Archean Slave craton were analyzed by FTIR for hydrogen contents. The 18 peridotites, two pyroxenites, one websterite and one wehrlite span an equilibration pressure range from 3.1 to 6.6 GPa and include samples from the shallow (? 145 km), oxidized ultra-depleted layer; the deeper (?145-180 km), reduced less depleted layer; and an ultra-deep (? 180 km) layer near the base of the lithosphere. Olivine, orthopyroxene, clinopyroxene and garnet from peridotites contain 30 - 145, 110 - 225, 105 - 285, 2 - 105 ppm H2O, respectively. Within each deep and ultra-deep layer, correlations of hydrogen contents in minerals and tracers of metasomatism (for example light over heavy rare-earth-element ratio (LREE/HREE), high-field-strength-element (HFSE) content with equilibration pressure) can be explained by a chromatographic process occurring during the percolation of kimberlite-like melts through garnet peridotite. The hydrogen content of peridotite minerals is controlled by the compositions of the evolving melt and of the minerals and by mineral/melt partition coefficients. At the beginning of the process, clinopyroxene scavenges most of the hydrogen and garnet most of the HFSE. As the melt evolves and becomes enriched in hydrogen and LREE, olivine and garnet start to incorporate hydrogen and pyroxenes become enriched in LREE. The hydrogen content of peridotite increases with decreasing depth, overall (e.g., from 75 to 138 ppm H2O in the deep peridotites). Effective viscosity calculated using olivine hydrogen content for the deepest xenoliths near the lithosphere-asthenosphere boundary overlaps with estimates of asthenospheric viscosities. These xenoliths cannot be representative of the overall cratonic root because the lack of viscosity contrast would have caused basal erosion of lithosphere. Instead, metasomatism must be confined in narrow zones channeling kimberlite melts through the lithosphere and from where xenoliths are preferentially sampled. Such localized metasomatism by hydrogen-bearing melts therefore does not necessarily result in delamination of the cratonic root.
DS202009-1622
2020
Griffin, W.L.Dai, H-K., Zheng, J.P., Griffin, W.L., O'Reilly, S.Y., Xiong, Q., Ping, X., Chen, F-K., Lu, J.Pyroxenite xenoliths record complex melt impregnation in the deep lithosphere of the northwestern North China Craton.Journal of Petrology, 10.1093/petrology/egaa079 110p. PdfChinaxenoliths

Abstract: Transformation of refractory cratonic mantle into more fertile lithologies is the key to the fate of cratonic lithosphere. This process has been extensively studied in the eastern North China Craton (NCC) while that of its western part is still poorly constrained. A comprehensive study of newly-found pyroxenite xenoliths from the Langshan area, in the northwestern part of this craton is integrated with a regional synthesis of pyroxenite and peridotite xenoliths to constrain the petrogenesis of the pyroxenites and provide an overview of the processes involved in the modification of the deep lithosphere. The Langshan pyroxenites are of two types, high-Mg# [Mg2+/(Mg2++Fe2+)*100 = ? 90, atomic ratios] olivine-bearing websterites with high equilibration temperatures (880 ? 970 oC), and low-Mg# (70 ? 80) plagioclase-bearing websterites with low equilibration temperatures (550 ? 835 oC). The high-Mg# pyroxenites show trade-off abundances of olivine and orthopyroxene, highly depleted bulk Sr-Nd (?Nd?=?+11.41, 87Sr/86Sr = ?0.7034) and low clinopyroxene Sr isotopic ratios (mean 87Sr/86Sr = ?0.703). They are considered to reflect the reaction of mantle peridotites with silica-rich silicate melts derived from the convective mantle. Their depletion in fusible components (e.g., FeO, TiO2 and Na2O) and progressive exhaustion of incompatible elements suggest melt extraction after their formation. The low-Mg# pyroxenites display layered structures, convex-upward rare earth element patterns, moderately enriched bulk Sr-Nd isotopic ratios (?Nd = -14.20 ? -16.74, 87Sr/86Sr?=?0.7070 ? 0.7078) and variable clinopyroxene Sr-isotope ratios (87Sr/86Sr?=?0.706-0.711). They are interpreted to be crustal cumulates from hypersthene-normative melts generated by interaction between the asthenosphere and heterogeneous lithospheric mantle. Combined with studies on regional peridotite xenoliths, it is shown that the thinning and refertilization of the lithospheric mantle was accompanied by crustal rejuvenation and that such processes occurred ubiquitously in the northwestern part of the NCC. A geodynamic model is proposed for the evolution of the deep lithosphere, which includes long-term mass transfer through a mantle wedge into the deep crust from the Paleozoic to the Cenozoic, triggered by subduction of the Paleo-Asian ocean and the Late Mesozoic lithospheric extension of eastern Asia.
DS202011-2047
2020
Griffin, W.L.Kilgore, M.L., Peslier, A.H., Brandon, A.D., Schaffer, L.A., Morris, R.V., Graff, T.G., Agresti, D.G., O'Reilly, S.Y., Griffin, W.L., Pearson, D.G., Barry, K.G., Shaulis, J.Metasomatic control of hydrogen contents in the layered cratonic mantle lithosphere sampled by Lac de Gras xenoliths in the central Slave Craton, Canada.Geochimica et Cosmochimica Acta, Vol. 286, pp. 29-83. pdfCanada, Northwest Territoriesxenoliths

Abstract: Whether hydrogen incorporated in nominally anhydrous mantle minerals plays a role in the strength and longevity of the thick cratonic lithosphere is a matter of debate. In particular, the percolation of hydrogen-bearing melts and fluids could potentially add hydrogen to the mantle lithosphere, weaken its olivines (the dominant mineral in mantle peridotite), and cause delamination of the lithosphere's base. The influence of metasomatism on hydrogen contents of cratonic mantle minerals can be tested in mantle xenoliths from the Slave Craton (Canada) because they show extensive evidence for metasomatism of a layered cratonic mantle. Minerals from mantle xenoliths from the Diavik mine in the Lac de Gras kimberlite area located at the center of the Archean Slave craton were analyzed by FTIR for hydrogen contents. The 18 peridotites, two pyroxenites, one websterite and one wehrlite span an equilibration pressure range from 3.1 to 6.6 GPa and include samples from the shallow (?145?km), oxidized ultra-depleted layer; the deeper (?145-180?km), reduced less depleted layer; and an ultra-deep (?180?km) layer near the base of the lithosphere. Olivine, orthopyroxene, clinopyroxene and garnet from peridotites contain 30-145, 110-225, 105-285, 2-105?ppm H2O, respectively. Within each deep and ultra-deep layer, correlations of hydrogen contents in minerals and tracers of metasomatism (for example light over heavy rare-earth-element ratio (LREE/HREE), high-field-strength-element (HFSE) content with equilibration pressure) can be explained by a chromatographic process occurring during the percolation of kimberlite-like melts through garnet peridotite. The hydrogen content of peridotite minerals is controlled by the compositions of the evolving melt and of the minerals and by mineral/melt partition coefficients. At the beginning of the process, clinopyroxene scavenges most of the hydrogen and garnet most of the HFSE. As the melt evolves and becomes enriched in hydrogen and LREE, olivine and garnet start to incorporate hydrogen and pyroxenes become enriched in LREE. The hydrogen content of peridotite increases with decreasing depth, overall (e.g., from 75 to 138?ppm H2O in the deep peridotites). Effective viscosity calculated using olivine hydrogen content for the deepest xenoliths near the lithosphere-asthenosphere boundary overlaps with estimates of asthenospheric viscosities. These xenoliths cannot be representative of the overall cratonic root because the lack of viscosity contrast would have caused basal erosion of lithosphere. Instead, metasomatism must be confined in narrow zones channeling kimberlite melts through the lithosphere and from where xenoliths are preferentially sampled. Such localized metasomatism by hydrogen-bearing melts therefore does not necessarily result in delamination of the cratonic root.
DS202012-2217
2020
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Saunders, M., Bindi, L., Alard, O., Toledo, V., O'Reilly, S.Y.Parageneses of TiB2 in corundum xenoliths from Mt. Carmel, Israel: siderophile behavior of boron under reducing conditions.American Mineralogist, Vol. 105, pp. 1609-1621. pdfEurope, Israeldeposit - Mt. Carmel

Abstract: Titanium diboride (TiB2) is a minor but common phase in melt pockets trapped in the corundum aggregates that occur as xenoliths in Cretaceous basaltic volcanoes on Mt. Carmel, north Israel. These melt pockets show extensive textural evidence of immiscibility between metallic (Fe-Ti-C-Si) melts, Ca-Al-Mg-Si-O melts, and Ti-(oxy)nitride melts. The metallic melts commonly form spherules in the coexisting oxide glass. Most of the observed TiB2 crystallized from the Fe-Ti-C silicide melts and a smaller proportion from the oxide melts. The parageneses in the melt pockets of the xenoliths require fO2 ? ?IW-6, probably generated through interaction between evolved silicate melts and mantle-derived CH4+H2 fluids near the crust-mantle boundary. Under these highly reducing conditions boron, like carbon and nitrogen, behaved mainly as a siderophile element during the separation of immiscible metallic and oxide melts. These parageneses have implications for the residence of boron in the peridotitic mantle and for the occurrence of TiB2 in other less well-constrained environments such as ophiolitic chromitites.
DS202012-2256
2020
Griffin, W.L.Zedgenizov, D.A., Skuzovatov, S.Y., Griffin, W.L., Pomazansky, B.S., Ragozin, A.:., Kalinina, V.V.Diamond forming HDFs tracking episodic mantle metasomatism beneath Nyurbinskaya kimberlite pipe (Siberian craton).Contributions to Mineralogy and Petrology, Vol. 175, 106, 21p. PdfRussiadeposit - Nyurbinskaya

Abstract: We present a new dataset on the composition of high-density fluids (HDFs) in cloudy (n?=?25), coated (n?=?10) and cuboid (n?=?10) diamonds from the Nyurbinskaya kimberlite pipe. These diamonds represent different populations each showing distinct growth histories. The cores of coated diamonds display multiple growth stages and contrasting sources of carbon. Fibrous coats and cuboid diamonds have similar carbon isotopes and nitrogen systematics, suggesting their formation in the last metasomatic events related to kimberlite magmatism, as is common for most such diamonds worldwide. The HDFs in most of these diamonds span a wide range from low-Mg carbonatitic to hydrous silicic compositions. The major- and trace-element variations suggest that the sources for such HDFs range in composition between the depleted mantle and more fertile mantle reservoirs. Hydrous-silicic HDFs could originate from a 13C-enriched source, which originates through subduction of crustal metasedimentary material. Percolation of such HDFs through carbonated eclogites and peridotites facilitates the formation of cuboid diamonds and fibrous coats in the mantle section beneath the corresponding area of the Siberian craton. Cloudy diamonds represent an apparently older population, reflecting continuous diamond formation predominantly from high-Mg carbonatitic HDFs that caused discrete episodes of diamond precipitation. Their high Mg# and enrichment in incompatible elements support a metasomatized peridotitic source for these HDFs.
DS202101-0001
2020
Griffin, W.L.Bindi, L., Camara, F., Gain, S.E.M., Griffin, W.L., Huang, J-X., Saunders, M., Toledo, V.Kishonite, VH2 and oreillyite, Cr2N, two new minerals from the conundrum xenocrysts of Mt. Carmel, northern Israel.Minerals MDPI, Vol. 10, 1118, doi:10.3390/ min10121118 10p. PdfEurope, Israeldeposit - Mt. Carmel

Abstract: Here, we describe two new minerals, kishonite (VH2) and oreillyite (Cr2N), found in xenoliths occurring in pyroclastic ejecta of small Cretaceous basaltic volcanoes exposed on Mount Carmel, Northern Israel. Kishonite was studied by single-crystal X-ray diffraction and was found to be cubic, space group Fm3¯m, with a = 4.2680(10) Å, V = 77.75(3) Å3, and Z = 4. Oreillyite was studied by both single-crystal X-ray diffraction and transmission electron microscopy and was found to be trigonal, space group P3¯1m, with a = 4.7853(5) Å, c = 4.4630(6) Å, V = 88.51 Å3, and Z = 3. The presence of such a mineralization in these xenoliths supports the idea of the presence of reduced fluids in the sublithospheric mantle influencing the transport of volatile species (e.g., C, H) from the deep Earth to the surface. The minerals and their names have been approved by the Commission of New Minerals, Nomenclature and Classification of the International Mineralogical Association (No. 2020-023 and 2020-030a).
DS202101-0008
2020
Griffin, W.L.Dessai, A.G., Viegas, A., Griffin, W.L.Thermal architecture of cratonic India and implications for decratonization of the western Dharwar craton: evidence from mantle xenoliths in the Deccan traps.Lithos, in press available, 56p. PdfIndiageothermometry

Abstract: The mantle beneath the Western Dharwar Craton of the Indian shield comprises a suite of refractory and fertile peridotites and mafic granulites. Detailed petrographic studies coupled with new mineral analysis and geothermobarometric estimations permit to decipher the thermal architecture and get an insight into the evolution of this ancient craton. The refractory rocks are coarse grained harzburgites/dunites, whereas the more fertile ones are at times, porphyroclastic lherzolites. Both show a similar range of equilibration temperatures and pressures indicating intermixing between the two at various levels. The peridotites contain undeformed interstitial REE-enriched clinopyroxene, phlogopite, apatite and carbonates recording post-kinematic modal and cryptic metasomatic events in the Precambrian cratonic lithosphere. Xenoliths of mafic granulite contain layers of clinopyroxenite which also vein the granulite. The P-T range of the granulites overlaps that of the ultramafic rocks. This study in combination with previous investigations reveals a distinct change in the thermal architecture of the craton from a warm/hot geotherm in the Proterozoic to a highly perturbed, still hotter geotherm of the Palaeocene. The Cenozoic thermotectonic rifting episodes heated, refertilized and thinned the bulk of the cratonic lithosphere beneath the Western Dharwar Craton, which has witnessed the most re-activation among cratons of the Indian shield. The waning of the Deccan Traps volcanism in Palaeocene time saw the reworking of ancient cratonic lithosphere and its replacement by non-cratonic, juvenile mantle and magmatic accretions, indicated by compound xenoliths. Differing petrological and geochemical characteristics of refractory xenoliths and fertile lherzolites serve to constrain the relative timing and composition of non-cratonic lithosphere. By the end of the Palaeocene the Western Dharwar Craton was characterised by a thermal high, an attenuated continental lithosphere (60-80 km), and a thin crust (<10- ~ 21 km), reflecting the decratonization of at least the western part of the Western Dharwar Craton.
DS202101-0013
2020
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Saunders, M., Bindi, L., Alard, O., Toledo, V., O'Reilly, S.Y.Parageneses of TIB2 in corundum xenoliths from Mt. Carmel, Israel: siderophile behaviour of boron under reducing conditions.American Mineralogist , in press available 33p. PdfEurope, Israeldeposit - Mt. Carmel

Abstract: Titanium diboride (TiB2) is a minor but common phase in melt pockets trapped in the corundum aggregates that occur as xenoliths in Cretaceous basaltic volcanoes on Mt. Carmel, north Israel. These melt pockets show extensive textural evidence of immiscibility between metallic (Fe-Ti-C-Si) melts, Ca-Al-Mg-Si-O melts, and Ti-(oxy)nitride melts. The metallic melts commonly form spherules in the coexisting oxide glass. Most of the observed TiB2 crystallized from the Fe-Ti-C silicide melts and a smaller proportion from the oxide melts. The parageneses in the melt pockets of the xenoliths require fO2 ? ?IW-6, probably generated through interaction between evolved silicate melts and mantle-derived CH4+H2 fluids near the crust-mantle boundary. Under these highly reducing conditions boron, like carbon and nitrogen, behaved mainly as a siderophile element during the separation of immiscible metallic and oxide melts. These parageneses have implications for the residence of boron in the peridotitic mantle and for the occurrence of TiB2 in other less well-constrained environments such as ophiolitic chromitites.
DS202102-0173
2020
Griffin, W.L.Aulbach, S., Giuliani, A., Fiorentini, M.L., Baumgartner, R.J., Davard, D., Kamenetsky, V.S., Caruso, S., Danyushevsky, L.V., Powell, W., Griffin, W.L.Siderophile and chalcophile elements in spinels, sulphides and native Ni in strongly metasomatised xenoliths from the Bultfontein kimberlite (South Africa).Lithos, doi.org/10.1016/ jlithos.2020.105880, 26p. PdfAfrica, South Africadeposit - Bultfontein

Abstract: The metasomatised continental mantle may play a key role in the generation of some ore deposits, in particular mineral systems enriched in platinum-group elements (PGE) and Au. The cratonic lithosphere is the longest-lived potential source for these elements, but the processes that facilitate their pre-concentration in the mantle and their later remobilisation to the crust are not yet well-established. Here, we report new results on the petrography, major-element, and siderophile- and chalcophile-element composition of native Ni, base metal sulphides (BMS), and spinels in a suite of well-characterised, highly metasomatised and weakly serpentinised peridotite xenoliths from the Bultfontein kimberlite in the Kaapvaal Craton, and integrate these data with published analyses. Pentlandite in polymict breccias (failed kimberlite intrusions at mantle depth) has lower trace-element contents (e.g., median total PGE 0.72 ppm) than pentlandite in phlogopite peridotites and Mica-Amphibole-Rutile-Ilmenite-Diopside (MARID) rocks (median 1.6 ppm). Spinel is an insignificant host for all elements except Zn, and BMS and native Ni account for typically <25% of the bulk-rock PGE and Au. High bulk-rock Te/S suggest a role for PGE-bearing tellurides, which, along with other compounds of metasomatic origin, may host the missing As, Ag, Cd, Sb, Te and, in part, Bi that are unaccounted for by the main assemblage. The close spatial relationship between BMS and metasomatic minerals (e.g., phlogopite, ilmenite) indicates that the lithospheric mantle beneath Bultfontein was resulphidised by metasomatism after initial melt depletion during stabilisation of the cratonic lithosphere. Newly-formed BMS are markedly PGE-poor, as total PGE contents are <4.2 ppm in pentlandite from seven samples, compared to >26 ppm in BMS in other peridotite xenoliths from the Kaapvaal craton. This represents a strong dilution of the original PGE abundances at the mineral scale, perhaps starting from precursor PGE alloy and small volumes of residual BMS. The latter may have been the precursor to native Ni, which occurs in an unusual Ni-enriched zone in a harzburgite and displays strongly variable, but overall high PGE abundances (up to 81 ppm). In strongly metasomatised peridotites, Au is enriched relative to Pd, and was probably added along with S. A combination of net introduction of S, Au +/? PGE from the asthenosphere and intra-lithospheric redistribution, in part sourced from subducted materials, during metasomatic events may have led to sulphide precipitation at ~80-120 km beneath Bultfontein. This process locally enhanced the metallogenic fertility of this lithospheric reservoir. Further mobilisation of the metal budget stored in these S-rich domains and upwards transport into the crust may require interaction with sulphide-undersaturated melts that can dissolve sulphides along with the metals they store.
DS202105-0759
2021
Griffin, W.L.Dai, H-K., Zheng, J-P., Griffin, W.L., O'Reilly, S.Y., Xiong, Q., Ping, X-Q., Chen, F-K., Lu, J-G.Pyroxenite xenoliths record complex melt impregnation in the deep lithosphere of the northwestern North China craton.Journal of Petrology, Vol. 62, 2, pp. 1-32. pdf.ChinaCraton

Abstract: Transformation of refractory cratonic mantle into more fertile lithologies is the key to the fate of cratonic lithosphere. This process has been extensively studied in the eastern North China Craton (NCC) while that of its western part is still poorly constrained. A comprehensive study of newly-found pyroxenite xenoliths from the Langshan area, in the northwestern part of this craton is integrated with a regional synthesis of pyroxenite and peridotite xenoliths to constrain the petrogenesis of the pyroxenites and provide an overview of the processes involved in the modification of the deep lithosphere. The Langshan pyroxenites are of two types, high-Mg# [Mg2+/(Mg2++Fe2+)*100 = ?90, atomic ratios] olivine-bearing websterites with high equilibration temperatures (880-970 oC), and low-Mg# (70-80) plagioclase-bearing websterites with low equilibration temperatures (550-835 oC). The high-Mg# pyroxenites show trade-off abundances of olivine and orthopyroxene, highly depleted bulk Sr-Nd (?Nd = +11•41, 87Sr/86Sr = ?0•7034) and low clinopyroxene Sr isotopic ratios (mean 87Sr/86Sr = ?0•703). They are considered to reflect the reaction of mantle peridotites with silica-rich silicate melts derived from the convective mantle. Their depletion in fusible components (e.g., FeO, TiO2 and Na2O) and progressive exhaustion of incompatible elements suggest melt extraction after their formation. The low-Mg# pyroxenites display layered structures, convex-upward rare earth element patterns, moderately enriched bulk Sr-Nd isotopic ratios (?Nd = -14•20- -16•74, 87Sr/86Sr = 0•7070-0•7078) and variable clinopyroxene Sr-isotope ratios (87Sr/86Sr = 0•706-0•711). They are interpreted to be crustal cumulates from hypersthene-normative melts generated by interaction between the asthenosphere and heterogeneous lithospheric mantle. Combined with studies on regional peridotite xenoliths, it is shown that the thinning and refertilization of the lithospheric mantle was accompanied by crustal rejuvenation and that such processes occurred ubiquitously in the northwestern part of the NCC. A geodynamic model is proposed for the evolution of the deep lithosphere, which includes long-term mass transfer through a mantle wedge into the deep crust from the Paleozoic to the Cenozoic, triggered by subduction of the Paleo-Asian Ocean and the Late Mesozoic lithospheric extension of eastern Asia.
DS202107-1121
2021
Griffin, W.L.Ozaydin, S., Selway, K., Griffin, W.L.Are xenoliths from southwestern Kaapvaal Craton representative of the broader mantle? Constraints from magnetotelluric modeling. KimberlitesAGU Research Letter, 10.1029/2021GL092570 11p. PdfAfrica, South Africageophysics - magnetotellurics

Abstract: Measuring the composition of the Earth’s mantle is important for understanding mantle processes like plate tectonics, but is surprisingly difficult. Our most accurate information comes from mantle rocks, called xenoliths, that have been brought to the surface during volcanic eruptions. However, these rocks only come from a handful of places. We tend to expect that the rest of the mantle has the same composition as the xenoliths but this might be incorrect. We tested whether xenolith compositions really are representative of the broader mantle by comparing them with compositions interpreted from electrical conductivity models of the mantle. We carried out this comparison in the Kimberley region, South Africa, because it has excellent xenolith and electrical conductivity data. Our results show that xenolith compositions do seem to be broadly representative but there are two important differences: Hydrous minerals found in some xenoliths may not be spatially extensive depending on temperature, and the water contents of some other minerals are different from the broader region. This means that the compositions of xenoliths are at least partly controlled by local processes. Electrical conductivity data may be more useful for measuring some aspects of the composition of the broader mantle, especially its water content.
DS202108-1286
2021
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Saunders, M., Alard, O., Shaw, J., Toledo, V.Nitrogen under super-reducing conditions: Ti Oxynitride melts in xenolithic corundum aggregates from Mt. Carmel.Minerals, Vol. 11, 780, 16p. PdfEurope, Israeldeposit - Mt. Carmel

Abstract: Titanium oxynitrides (Ti(N,O,C)) are abundant in xenolithic corundum aggregates in pyroclastic ejecta of Cretaceous volcanoes on Mount Carmel, northern Israel. Petrographic observations indicate that most of these nitrides existed as melts, immiscible with coexisting silicate and Fe-Ti-C silicide melts; some nitrides may also have crystallized directly from the silicide melts. The TiN phase shows a wide range of solid solution, taking up 0-10 wt% carbon and 1.7-17 wt% oxygen; these have crystallized in the halite (fcc) structure common to synthetic and natural TiN. Nitrides coexisting with silicide melts have higher C/O than those coexisting with silicate melts. Analyses with no carbon fall along the TiN-TiO join in the Ti-N-O phase space, implying that their Ti is a mixture of Ti3+ and Ti2+, while those with 1-3 at.% C appear to be solid solutions between TiN and Ti0.75O. Analyses with >10 at% C have higher Ti2+/Ti3+, reflecting a decrease in fO2. Oxygen fugacity was 6 to 8 log units below the iron-wüstite buffer, at or below the Ti2O3-TiO buffer. These relationships and coexisting silicide phases indicate temperatures of 1400-1100 °C. Ti oxynitrides are probably locally abundant in the upper mantle, especially in the presence of CH4-H2 fluids derived from the deeper metal-saturated mantle.
DS202109-1459
2021
Griffin, W.L.Dessai, A.G., Griffin, W.L. Decratonization and reactivation of the southern Indian shield: an integrated perspective. Earth Science Reviews , Vol. 220, 103702 16p. PdfIndiacraton - Dharwar

Abstract: A 150-200 km thick, cold (35-45 mWm?2), melt-depleted lithospheric keel characterised the eastern cratons of the Indian shield at the end of the Precambrian. Differing chemical- and isotopic-characteristics, and ages of the crust and mantle rocks reveal the decoupling of the crust and mantle beneath the cratons, beginning at 2.45 Ga, in the Bastar craton. The Pan-African event was more pervasive and brought about widespread reworking in most of the cratons of the shield. Major-, trace- and rare-earth elements combined with Sr, Nd and Hf isotope data suggest a heterogenous SCLM beneath southern India. The trace element signatures of xenoliths and the presence of majoritic garnet inclusions in diamond suggest that some kimberlites were derived from the mantle transition zone. Mesoproterozoic (1.2-1.4 Ga) modal and cryptic refertilisation by asthenosphere-derived, low-degree carbonated melts led to the generation of the fluids responsible for the metasomatic transformation of the source rocks. The western craton of the shield has witnessed more severe reactivation than the eastern due to the frequent interaction of the Indian plate with mantle plumes. One plume caused major igneous activity during the late Cretaceous, synchronous with crustal attenuation, rifting and the ridge-jump at 66 Ma, in the Indian Ocean. By the end of the Palaeocene the geotherm of the western craton had risen from 50 to 55 mWm?2 in the Proterozoic to a peak 80-90 mWm?2. This increase in heat flow not only modulated the mantle thermal regime, but led to a net loss of more than 100 km of lithosphere and to destabilisation of the craton. After this thermal event, the lithosphere preserves a thickness of barely 60-80 km, and a thin crust (10-21 km) beneath the continental margin in the west. These changes decratonized the western part of the shield and the transitional region further west in the Indian Ocean where the continental ridges are almost devoid of crustal sections and the lithosphere is ~60 km thick. The waning of the Deccan Traps (65 Ma) magmatism was marked by alkaline intrusive activity along the western margin of the shield, probably derived from the SCLM in response to the rise of the mantle plume. Low degree (2-3%) partial melting of a modally and cryptically metasomatized source may have been involved in the generation of alkaline magmas from a depleted mantle source variously contaminated by an enriched endmember.
DS202110-1616
2021
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Saunders, M., Camara, F., Bindi, L., Sparta, D., Toledo, V., O'Reilly, S.Y.Cr203 in corundum: ultrahigh contents under reducing conditions. American Mineralogist, Vol. 106, pp. 1420-1437. pdfEurope, Israeldeposit - Mount Carmel

Abstract: Xenocrysts and xenoliths in Upper Cretaceous pyroclastics on Mount Carmel (northern Israel) represent a series of similar magma-fluid systems at different stages of their evolution, recording a continuous decrease in oxygen fugacity (fO2) as crystallization proceeded. Corundum coexisting with Fe-Mg-Cr-Al spinels, other Fe-Mg-Al-Na oxides, and Fe-Ni alloys in apparent cumulates crystallized at fO2 values near the iron-wüstite (IW) buffer (fO2 = IW±1) and is zoned from high-Cr cores to lower-Cr rims, consistent with fractional crystallization trends. The reconstructed parental melts of the cumulates are Al-Cr-Fe-Mg oxides with ca. 2 wt% SiO2. Corundum in other possible cumulates that contain Cr-Fe (Fe 45 wt%) alloys has low-Cr cores and still lower-Cr rims. Corundum coexisting with Cr0 (fO2 = IW-5) in some possible cumulates has low-Cr cores, but high-Cr rims (to >30% Cr2O3). These changes in zoning patterns reflect the strong decrease in the melting point of Cr2O3, relative to Al2O3, with decreasing fO2. The electron energy loss spectroscopy (EELS) analyses show that all Cr in corundum that coexists with Cr0 is present as Cr3+. This suggests that late in the evolution of these reduced melts, Cr2+ has disproportionated via the reaction 3Cr2+(melt) ? 2Cr3+(Crn) + Cr0. The most Cr-rich corundum crystallized together with ?-alumina phases including NaAl11O17 (diaoyudaoite) and KAl11O17 (kahlenbergite) and ??-alumina phases; residual melts crystallized a range of (K,Mg)2(Al,Cr)10O17 phases with the kahlenbergite structure. The parental melts of these assemblages appear to have been Al-Cr-K-Na-Mg oxides, which may be related to the Al-Cr-Fe-Mg oxide melts mentioned above, through fractional crystallization or liquid immiscibility. These samples are less reduced (fO2 from IW to IW-5) than the assemblages of the trapped silicate melts in the more abundant xenoliths of corundum aggregates (fO2 = IW-6 to IW-10). They could be considered to represent an earlier stage in the fO2 evolution of an “ideal” Mt. Carmel magmatic system, in which mafic or syenitic magmas were fluxed by mantle-derived CH4+H2 fluids. This is a newly recognized step in the evolution of the Mt. Carmel assemblages and helps to understand element partitioning under highly reducing conditions.
DS202110-1631
2021
Griffin, W.L.Ozaydin, S., Selway, K., Griffin, W.L., Moorkamp, M.Probing the southern African lithosphere with magnetotellurics, Part II, linking electrical conductivity, composition and tectono-magmatic evolution.Journal of Geophysical Research: Solid Earth , preprint available 40p. PdfAfricakimberlites

Abstract: The tectonic history of Southern Africa includes Archean formation of cratons, multiple episodes of subduction and rifting and some of the world's most significant magmatic events. These processes left behind a compositional trail that can be observed in xenoliths and measured by geophysical methods. The abundance of kimberlites in southern Africa makes it an ideal place to test and calibrate mantle geophysical interpretations that can then be applied to less well-constrained regions. Magnetotellurics (MT) is a particularly useful tool for understanding tectonic history because electrical conductivity is sensitive to temperature, bulk composition, accessory minerals and rock fabric. We produced three-dimensional MT models of the southern African mantle taken from the SAMTEX MT dataset, mapped the properties of $\sim36000$ garnet xenocrysts from Group I kimberlites, and compared the results. We found that depleted regions of the mantle are uniformly associated with high electrical resistivities. The conductivity of fertile regions is more complex and depends on the specific tectonic and metasomatic history of the region, including the compositions of metasomatic fluids or melts and the emplacement of metasomatic minerals. The mantle beneath the $\sim 2.05$ Ga Bushveld Complex is highly conductive, probably caused by magmas flowing along a lithospheric weakness zone and precipitating interconnected, conductive accessory minerals such as graphite and sulfides. Kimberlites tend to be emplaced near the edges of the cratons where the mantle below 100 km depth is not highly resistive. Kimberlites avoid strong mantle conductors, suggesting a systematic relationship between their emplacement and mantle composition.
DS202112-1957
2021
Griffin, W.L.Xu, J-Y., Giuliani, A., Li, Q-L., Lu, K., Melgarejo, J.C., Griffin, W.L.Light oxygen isotopes in mantle-derived magmas reflect assimilation of sub-continental lithospheric mantle material.Nature Communications, 10.10.1038/s4167-021-266668-z 14p. PdfMantleolivine

Abstract: Oxygen isotope ratios in mantle-derived magmas that differ from typical mantle values are generally attributed to crustal contamination, deeply subducted crustal material in the mantle source or primordial heterogeneities. Here we provide an alternative view for the origin of light oxygen-isotope signatures in mantle-derived magmas using kimberlites, carbonate-rich magmas that assimilate mantle debris during ascent. Olivine grains in kimberlites are commonly zoned between a mantle-derived core and a magmatic rim, thus constraining the compositions of both mantle wall-rocks and melt phase. Secondary ion mass spectrometry (SIMS) analyses of olivine in worldwide kimberlites show a remarkable correlation between mean oxygen-isotope compositions of cores and rims from mantle-like 18O/16O to lower ‘crustal’ values. This observation indicates that kimberlites entraining low-18O/16O olivine xenocrysts are modified by assimilation of low-18O/16O sub-continental lithospheric mantle material. Interaction with geochemically-enriched domains of the sub-continental lithospheric mantle can therefore be an important source of apparently ‘crustal’ signatures in mantle-derived magmas.
DS202204-0520
2022
Griffin, W.L.Griffin, W.L., Gain, S.E.M., Saunders, M.J., Huang, J-X., Alard, O., Toledo, V., O'Reilly, S.Y.Immiscible metallic melts in the upper mantle beneath Mount Carmel, Israel: silicides, phosphides, and carbides.American Mineralogist, Vol. 107, pp. 532-549.Europe, Israeldeposit - Mount Carmel

Abstract: Xenolithic corundum aggregates in Cretaceous mafic pyroclastics from Mount Carmel contain pockets of silicate melts with mineral assemblages [SiC (moissanite), TiC, Ti2O3 (tistarite), Fe-Ti-Zr silicides/phosphides] indicative of magmatic temperatures and oxygen fugacity (fO2) at least 6 log units below the iron-wüstite buffer (?IW ? -6). Microstructural evidence indicates that immiscible, carbon-rich metallic (Fe-Ti-Zr-Si-P) melts separated during the crystallization of the silicate melts. The further evolution of these metallic melts was driven by the crystallization of two main ternary phases (FeTiSi and FeTiSi2) and several near-binary phases, as well as the separation of more evolved immiscible melts. Reconstructed melt compositions fall close to cotectic curves in the Fe-Ti-Si system, consistent with trapping as metallic liquids. Temperatures estimated from comparisons with experimental work range from ?1500 °C to ca. 1150 °C; these probably are maximum values due to the solution of C, H, P, and Zr. With decreasing temperature (T), the Si, Fe, and P contents of the Fe-Ti-Si melts increased, while contents of Ti and C decreased. The increase in Si with declining T implies a corresponding decrease in fO2, probably to ca. ?IW-9. The solubility of P in the metallic melts declined with T and fO2, leading to immiscibility between Fe-Ti-Si melts and (Ti,Zr)-(P,Si) melts. Decreasing T and fO2 also reduced the solubility of C in the liquid metal, driving the continuous crystallization of TiC and SiC during cooling. The lower-T metallic melts are richer in Cr, and to some extent V, as predicted by experimental studies showing that Cr and V become more siderophile with decreasing fO2. These observations emphasize the importance of melt-melt immiscibility for the evolution of magmas under reducing conditions. The low fO2 and the abundance of carbon in the Mt. Carmel system are consistent with a model in which differentiating melts were fluxed by fluids that were dominated by CH4+H2, probably derived from a metal-saturated sublithospheric mantle. A compilation of other occur-rences suggests that these phenomena may commonly accompany several types of explosive volcanism.
DS202204-0521
2022
Griffin, W.L.Guiliani, A., Drysdale, R.N., Woodhead, J.D., Planavsky, N.J., Phillips, D., Hergt, J., Griffin, W.L., Oesch, S., Dalton, H., Davies, G.R.Pertubation of the deep-Earth carbon cycle in response to the Cambrian explosion.Science Advances, doi.10.1126/sciadv.abj1325 1p. PdfMantlesubduction

Abstract: Earth’s carbon cycle is strongly influenced by subduction of sedimentary material into the mantle. The composition of the sedimentary subduction flux has changed considerably over Earth’s history, but the impact of these changes on the mantle carbon cycle is unclear. Here, we show that the carbon isotopes of kimberlite magmas record a fundamental change in their deep-mantle source compositions during the Phanerozoic Eon. The 13C/12C of kimberlites before ~250 Ma preserves typical mantle values, whereas younger kimberlites exhibit lower and more variable ratios-a switch coincident with a recognized surge in kimberlite magmatism. We attribute these changes to increased deep subduction of organic carbon with low 13C/12C following the Cambrian Explosion when organic carbon deposition in marine sediments increased significantly. These observations demonstrate that biogeochemical processes at Earth’s surface have a profound influence on the deep mantle, revealing an integral link between the deep and shallow carbon cycles.
DS202204-0522
2022
Griffin, W.L.Huang, J., Huang, J-X., Griffin, W.L., Huang, F.Zn- Mg- and O-isotope evidence for the origin of mantle eclogites from Roberts Victor kimberlite ( Kaapvaal Craton, South Africa).Geology, doi.1130/G49780.1Africa, South Africadeposit - Roberts Victor

Abstract: We report Zn-isotope compositions of garnet, clinopyroxene, and whole rocks for 14 Type I and 10 Type II eclogites from the Roberts Victor kimberlite (Kaapvaal Craton, South Africa) that were previously analyzed for Mg-O isotopes. Type II eclogites are the protoliths of the highly metasomatized Type I. Garnet and clinopyroxene in Type II eclogites have ?66Zn from 0.14‰ to 0.50‰ and from 0.29‰ to 0.58‰, respectively; reconstructed whole-rock ?66Zn is from 0.24‰ to 0.54‰, which is higher than typical mantle values (0.16-0.20‰). Their heavy Zn- and light Mg- and O-isotope compositions (?26Mg = -1.1‰ to -0.14‰, ?18O = 2.3‰ to 4.9‰) cannot originate from subducted, carbonate-rich, altered oceanic crust, which is enriched in heavy Zn-O and light Mg isotopes. The low ?18O may be inherited from parental melts derived from low-?18O mantle sources like those that produced the Weltevreden komatiites of the Kaapvaal Craton. The high ?66Zn and low ?26Mg reflect diffusion-driven Zn-Mg-isotope exchange between peridotites and the parental melts during their emplacement in the deep lithosphere. Type I eclogites have reconstructed whole-rock ?66Zn from 0.03‰ to 0.43‰ and garnet ?18O from 6‰ to 9.1‰ but show more scatter in inter-mineral Zn-isotope fractionation than Type II, reflecting incomplete equilibration during later metasomatism by carbonatitic-to-kimberlitic melts. Our evidence from multiple isotopes thus suggests that the Roberts Victor eclogites might have crystallized from deep-seated melts at mantle depths.
DS202204-0532
2022
Griffin, W.L.Ozaydin, S., Selway, K., Griffin, W.L., Moorkamp, M.Probing the southern African lithosphere with magnetotellurics, Part II, linking electrical conductivity, composition and techonomagamatic evolution.Journal of Geophysical Research: Solid Earth, doi: 10.1029/2021JB023105Africageophysics

Abstract: The present-day composition of Earth's tectonic plates results from past geological processes. We can learn about Earth's composition from deep rock samples that are carried to the surface during volcanic eruptions and by probing its physical properties, like electrical conductivity, with geophysics. In southern Africa, there are extensive deep rock samples, which have been brought to the surface by kimberlite volcanoes that also host diamonds, and also extensive geophysical data. In this article, we compare the rock compositions with electrical conductivity to learn more about Earth's composition. Our results show that the oldest parts of the plates, which retain compositions similar to their initial composition, appear resistive. On the other hand, regions that have been intruded by deep fluids or molten rock can be resistive or conductive, depending on the types of minerals that were formed during the intrusion. The kimberlite volcanoes mostly erupted through the edges of the most resistive parts of the plates and did not erupt through the conductors. These results will help us to make more accurate interpretations about the composition of parts of the Earth where we do not have deep rock samples.
DS202205-0672
2022
Griffin, W.L.Afonso, J., Ben-Mansour, W., O'Reilly, S.Y., Griffin, W.L., Salajeghegh, F., Foley, S., Begg, G., Selway, K., Macdonald, A., Januszczak, N., Fomin, I., Nyblade, A.A., Yang, Y.Thermochemical structure and evolution of cratonic lithosphere in central and southern Africa.Nature Geoscience, Apr. 26, 329p. FreeAfrica, South AfricaCraton

Abstract: The thermochemical structure of the subcontinental mantle holds information on its origin and evolution that can inform energy and mineral exploration strategies, natural hazard mitigation and evolutionary models of Earth. However, imaging the fine-scale thermochemical structure of continental lithosphere remains a major challenge. Here we combine multiple land and satellite datasets via thermodynamically constrained inversions to obtain a high-resolution thermochemical model of central and southern Africa. Results reveal diverse structures and compositions for cratons, indicating distinct evolutions and responses to geodynamic processes. While much of the Kaapvaal lithosphere retained its cratonic features, the western Angolan-Kasai Shield and the Rehoboth Block have lost their cratonic keels. The lithosphere of the Congo Craton has been affected by metasomatism, increasing its density and inducing its conspicuous low-topography, geoid and magnetic anomalies. Our results reconcile mantle structure with the causes and location of volcanism within and around the Tanzanian Craton, whereas the absence of volcanism towards the north is due to local asthenospheric downwellings, not to a previously proposed lithospheric root connecting with the Congo Craton. Our study offers improved integration of mantle structure, magmatism and the evolution and destruction of cratonic lithosphere, and lays the groundwork for future lithospheric evolutionary models and exploration frameworks for Earth and other terrestrial planets.
DS202205-0687
2022
Griffin, W.L.Huang, J., Huang, J-X., Griffin, W.L., Huang, F.Zn-, Mg- and O isotope evidence for the origin of mantle eclogites from Roberts Victor kimberlite ( Kaapvaal Craton, South Africa.Geology, Vol. 50, 5, pp. 593-597.Africa, South Africadeposit - Roberts Victor

Abstract: We report Zn-isotope compositions of garnet, clinopyroxene, and whole rocks for 14 Type I and 10 Type II eclogites from the Roberts Victor kimberlite (Kaapvaal Craton, South Africa) that were previously analyzed for Mg-O isotopes. Type II eclogites are the protoliths of the highly metasomatized Type I. Garnet and clinopyroxene in Type II eclogites have ?66Zn from 0.14‰ to 0.50‰ and from 0.29‰ to 0.58‰, respectively; reconstructed whole-rock ?66Zn is from 0.24‰ to 0.54‰, which is higher than typical mantle values (0.16-0.20‰). Their heavy Zn- and light Mg- and O-isotope compositions (?26Mg = ?1.1‰ to ?0.14‰, ?18O = 2.3‰ to 4.9‰) cannot originate from subducted, carbonate-rich, altered oceanic crust, which is enriched in heavy Zn-O and light Mg isotopes. The low ?18O may be inherited from parental melts derived from low-?18O mantle sources like those that produced the Weltevreden komatiites of the Kaapvaal Craton. The high ?66Zn and low ?26Mg reflect diffusion-driven Zn-Mg-isotope exchange between peridotites and the parental melts during their emplacement in the deep lithosphere. Type I eclogites have reconstructed whole-rock ?66Zn from 0.03‰ to 0.43‰ and garnet ?18O from 6‰ to 9.1‰ but show more scatter in inter-mineral Zn-isotope fractionation than Type II, reflecting incomplete equilibration during later metasomatism by carbonatitic-to-kimberlitic melts. Our evidence from multiple isotopes thus suggests that the Roberts Victor eclogites might have crystallized from deep-seated melts at mantle depths.
DS202205-0711
2021
Griffin, W.L.Ozaydin, S., Selway, K., Griffin, W.L., Moorkamp, M.Probing the southern African lithosphere with magnetotellurics: 2 linking electrical conductivity, composition, and tectonomagmatic evolution.Journal of Geophysical Research, 10.1029/2021JB023105, 28p.Africa, South Africageophysics - magnetotellurics

Abstract: The present-day composition of Earth's tectonic plates results from past geological processes. We can learn about Earth's composition from deep rock samples that are carried to the surface during volcanic eruptions and by probing its physical properties, like electrical conductivity, with geophysics. In southern Africa, there are extensive deep rock samples, which have been brought to the surface by kimberlite volcanoes that also host diamonds, and also extensive geophysical data. In this article, we compare the rock compositions with electrical conductivity to learn more about Earth's composition. Our results show that the oldest parts of the plates, which retain compositions similar to their initial composition, appear resistive. On the other hand, regions that have been intruded by deep fluids or molten rock can be resistive or conductive, depending on the types of minerals that were formed during the intrusion. The kimberlite volcanoes mostly erupted through the edges of the most resistive parts of the plates and did not erupt through the conductors. These results will help us to make more accurate interpretations about the composition of parts of the Earth where we do not have deep rock samples.
DS2001-0414
2001
Griffin, W.L.WinGriffin, W.L.Win, Davies, Wathanakul, Andrew, MetcalfeDiamonds from Myanmar and Thailand: characteristics and possible originsEconomic Geology, Vol. 96, No. 1, Jan-Feb. pp. 159-79.GlobalAlluvials, Diamond - morphology, textures, chemistry
DS1998-1134
1998
Griffin.Pearson, D.G., Davies, R., Shirey, Carlson, R., Griffin.The age and origin of eastern Australian diamonds: Rhenium- Osmium (Re-Os) isotope evidence from sulfide inclusions...7th. Kimberlite Conference abstract, pp. 664-6.Australia, New South WalesDiamond inclusions, geochronology, Deposit - Copeton, Bingara
DS1860-0987
1897
Griffith, G.Griffith, G.Diamond Digging at De Beers minePearsons Magazine., MAY, P.Africa, South AfricaHistory
DS1860-1085
1899
Griffith, G.Griffith, G.Knaves of Diamonds, Being Tales of Mine and VeldLondon: Pearson., 272P.Africa, South AfricaHistory
DS1991-0209
1991
Griffith, R.W.Campbell, I.H., Griffith, R.W.Megaplumes and giant radiating dyke swarmsGeological Association of Canada (GAC)/Mineralogical Association of Canada/Society Economic, Vol. 16, Abstract program p. A19AustraliaDykes, Geothermometry
DS1960-0053
1960
Griffith, S.V.Griffith, S.V.Hydraulic Mining: Alluvial Prospecting and MiningLondon: Pergamon Press, 245P.South Africa, GlobalMining Methods, Diamond, Recovery
DS1960-0054
1960
Griffith, S.V.Griffith, S.V.The Diamondiferous Gravels of Southwest AfricaAlluvial Prospecting And Mining, Pergamon Press, Oxford., 245P. PP. 221-223.Southwest Africa, NamibiaLittoral Diamond Placers, Mining Methods
DS1900-0558
1907
Griffiths, H.D.Griffiths, H.D.Paardeberg Mines and DistrictSouth Africa Mines Commerce and Industry, Vol. 5, PT. 1, MARCH 23RD. No. 211, P. 54. PART 2, Vol. 5, PAfrica, South AfricaProspecting
DS1989-0552
1989
Griffiths, J.Griffiths, J.South Africa's minerals.. diversity in adversityIndustrial Minerals, No. 263, August pp. 18-53South AfricaOverview -minerals, Industrial minerals
DS1991-0613
1991
Griffiths, J.Griffiths, J.Industrial minerals directory: a world guide to producers and processors.2nd. editionMetal Bulletin Books, 557p. Cost?GlobalIndustrial minerals, Directory
DS1991-1655
1991
Griffiths, J.A.Stavnezer, J., and reply Reaban, M.E., Griffiths, J.A.Triple helix stabilizationNature, Vol. 351, No. 6326, June 6, p. 447GlobalStructure, Tectonics
DS1992-0621
1992
Griffiths, J.C.Griffiths, J.C., Smith, C.M.Jr.Mineral resources versus geologic diversity in small areasComputers and Geosciences, Vol. 18, No. 5, pp. 477-486GlobalComputer, ore reserves, Mineral resources
DS1997-0446
1997
Griffiths, J.C.Griffiths, J.C., Pilant, A.D., Smith, C.M.Quantitative assessment of the geology of large regions and their application to mineral resource assessmentNonrenewable Resources, Vol. 6, No. 3, Sept. pp. 157-236GlobalPetrographic index, mineral resource values, classification, reserves, geostatistics
DS1987-0438
1987
Griffiths, R.W.Martin, D., Griffiths, R.W., Campbell, I.H.Compositional and thermal convection in magma chambersContributions to Mineralogy and Petrology, Vol. 96, No. 4, pp. 465-475GlobalXenoliths
DS1988-0272
1988
Griffiths, R.W.Griffiths, R.W., Turner, J.S.Viscous entrainment by sinking plumesEarth and Planetary Science Letters, Vol. 90, No. 4, November 25, pp. 467-477GlobalCrust, Genesis
DS1989-0202
1989
Griffiths, R.W.Campbell, I.H., Griffiths, R.W., Hill, R.I.Melting in an Archean mantle plume: heads it's basalts, tails it'skomatiitesNature, Vol. 339, No. 6227, June 29, pp. 697-698.Database#18086GlobalKomatiite, Mantle
DS1990-0264
1990
Griffiths, R.W.Campbell, I.H., Griffiths, R.W.Implications of mantle plume structure for the evolution of flood basaltsEarth and Planetary Science Letters, Vol. 99, pp. 79-83GlobalMantle, Geochemistry -plumes structure
DS1990-0605
1990
Griffiths, R.W.Griffiths, R.W., Campbell, I.H.Stirring and structure in mantle starting plumesEarth and Planetary Science Letters, Vol. 99, pp. 66-78GlobalMantle, Geochemistry -plumes
DS1991-0614
1991
Griffiths, R.W.Griffiths, R.W., Campbell, I.H.On the dynamics of long lived plume conduits in the convecting mantleEarth Planetary Science Letters, Vol. 103, No. 1-4, April pp. 214-227GlobalMantle, Plumes
DS1991-0714
1991
Griffiths, R.W.Hill, R.I., Campbell, I.H., Griffiths, R.W.Plume tectonics and the development of stable continental crustAustralian Society of Exploration Geophysicists and Geological Society of, Vol. 22, No. 1, March pp. 185-188AustraliaMantle, Plumes
DS1992-0204
1992
Griffiths, R.W.Campbell, I.H., Griffiths, R.W.The changing nature of mantle hotspots through time: implications for the chemical evolution of the mantleJournal of Geology, Vol. 100, No. 5, September pp. 497-524GlobalMantle chemistry, geochemistry, Hotspots
DS1992-0205
1992
Griffiths, R.W.Campbell, I.H., Griffiths, R.W.The changing nature of mantle hotspots through time - implications for the chemical evolution of the mantleJournal of Geology, Vol. 100, No. 5, September pp. 497-524MantleHotspots, Geochemistry
DS1992-0709
1992
Griffiths, R.W.Hill, R.I., Campbell, I.H., Davies, G.F., Griffiths, R.W.Mantle plumes, continental magmatism and tectonicsEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.326MantleTectonics, Plumes
DS1993-0200
1993
Griffiths, R.W.Campbell, I.H., Griffiths, R.W.The evolution of the mantle's chemical structure #1Lithos, Vol. 30, No. 3-4, September pp. 389-400.MantleGeochemistry, Evolution
DS1993-0201
1993
Griffiths, R.W.Campbell, I.H., Griffiths, R.W.The evolution of the mantle's chemical structureLithos, Vol. 30, No. 3-4, September pp. 389-400MantleGeochemistry, Tectonics
DS1999-0336
1999
Griffiths, R.W.Jellinek, A.M., Kerr, R.C., Griffiths, R.W.Mixing and compositional stratification produced by natural convection.1.experiments and their applicationJournal of Geophysical Research, Vol. 104, No. 4, Apr. 10, pp. 7183-7202.MantleEarth's core and mantle, Petrology - experimental
DS2002-0616
2002
Griffiths, R.W.Griffiths, R.W., Whitehead, J.A.Earth's surface morphology and convection in the mantleSpringer, Lecture notes in Geophysics, No. 582, pp.111-37.MantleGeophysics, Convection - review
DS2003-0715
2003
Griffiths, R.W.Kincaid, C., Griffiths, R.W.Laboratory models of the thermal evolution of the mantle during rollback subductionNature, No. 6953, September 4, pp.58-61.MantleSubduction zone, geometry, geothermometry, geochemistry
DS200412-1003
2003
Griffiths, R.W.Kincaid, C., Griffiths, R.W.Laboratory models of the thermal evolution of the mantle during rollback subduction.Nature, No. 6953, September 4, pp.58-61.MantleSubduction zone, geometry, geothermometry, geochemistry
DS201412-0093
2014
Griffiths, R.W.Campbell, I.H., Griffiths, R.W.Did the formation of D" cause the Archean-Proterozoic transition?Earth and Planetary Science Letters, Vol. 388, pp. 1-8.MantlePlume, MgO
DS1990-0265
1990
Griffths, R.W.Campbell, I.H., Griffths, R.W.Implications of mantle plume structure for the evolution of flood basaltsEarth and Planetary Science Letters, Vol. 99, pp. 79-93.MantleFlood basalts - not specific to diamond
DS1994-0688
1994
Grifin, B.J.Gwalani, L.G., Grifin, B.J., Chang, W-J., Roday, P.P.Alkaline and tholeiitic dyke swarms of Chhota Udaipur Complex, GujaratIndia.Geological Association of Canada (GAC) Abstract Volume, Vol. 19, p. PosterIndiaAlkaline rocks, Dyke
DS1930-0298
1939
Griggs, D.Hurlburt, C.S.JR., Griggs, D.Igneous Rocks of the Highwood Mountains, Montana. Part I. The Laccoliths.Geological Society of America (GSA) Bulletin., Vol. 50, PP. 1043-1112.United States, Montana, Rocky MountainsBlank
DS1930-0197
1935
Griggs, D.T.Larsen, E.S., Hurlburt, C.S. JR., Burgess, C.H., Griggs, D.T.The Igneous Rocks of the Highwood Mountains of Central Montana.American GEOPYS. UNION, Transactions 16TH. MEETING, PP. 288-292.United States, Montana, Rocky MountainsBlank
DS200712-0384
2007
Grigne, C.Grigne, C., Labrosse, S., Tackley, P.J.Convection under a lid of finite conductivity in wide aspect ratio models: effect of continents on the rate of mantle flow.Journal of Geophysical Research, Vol. 112, B8, B08403MantleConvection
DS200712-0385
2007
Grigne, C.Grigne, C., Labrosse, S., Tackley, P.J.Convection under a lid of finite conductivity in wide aspect ratio models: heat flux scaling and application to continents.Journal of Geophysical Research, Vol. 112, B8, B08402MantleConvection
DS1997-0447
1997
Grigorev, N.A.Grigorev, N.A.Mineral concentrators as carriers of major chemical elements in the Upper Continental crust.Geochemistry International, Vol. 35, No. 6, June 1, pp. 499-503.MantleGeochemistry, Crust
DS2003-0505
2003
Grigorev, N.A.Grigorev, N.A.Average concentrations of chemical elements in rocks of the upper continental crustGeochemistry International, Vol. 41, 7, pp. 711-18.GlobalRock - mineral chemistry
DS200412-0727
2003
Grigorev, N.A.Grigorev, N.A.Average concentrations of chemical elements in rocks of the upper continental crust.Geochemistry International, Vol. 41, 7, pp. 711-18.TechnologyRock - mineral chemistry
DS1984-0319
1984
Grigoriev, A.P.Grigoriev, A.P., Kovalsky, V.V.Working of Diamond With MetalIndiaqua., Vol. 39, No. 3, PP. 47-54.GlobalMetallurgy
DS200912-0269
2009
Grigorieva, A.A.Grigorieva, A.A., Zubkova, N.V., Pekov, I.V., Pushcharvsky, D.Yu.Crystal structure of hilarite from Khibiny alkaline massif ( Kola Peninsula).Doklady Earth Sciences, Vol. 428, 1, pp. 1051-1053.Russia, Kola PeninsulaAlkalic
DS1990-0606
1990
Grigsby, J.D.Grigsby, J.D.Detrital magnetite as a provenance indicatorJournal of Sed. Petrology, Vol. 60, No. 6, November pp. 940-951GlobalGeochemistry, Magnetite
DS1992-0622
1992
Grigsby, J.D.Grigsby, J.D.Chemical fingerprinting in detrital ilmenite- a viable alternative inprovenance researchJournal of Sed. Petrology, Vol. 62, No. 2, March pp. 331-337GlobalIlmenite, Sedimentology
DS2002-0617
2002
Grikurov, G.E.Grikurov, G.E., Mikhalskii, E.V.Tectonic structure and evolution of east Antarctica in the light of knowledge about supercontinents.Russian Journal of Earth Science, Vol. 4, 4, AugustAntarcticaTectonics
DS1984-0283
1984
Grimes, G.W.Fraser, D.G., Watt, F., Grimes, G.W., Takacs, J.Direct Determination of Strontium Enrichment on Grain Boundaries in a Garnet Lherzolite Xenolith by Proton Microprobe Analysis.Nature., Vol. 312, No. 5992, PP. 352-354.GlobalBlank
DS1930-0225
1936
Grimes-Graeme, R.Osborne, F.F., Grimes-Graeme, R.The Breccia of St. Helen's Island, MontrealAmerican Journal of Science, Vol. 32, No. 187, PP. 43-54.Canada, QuebecRelated Rocks, Diatreme
DS1930-0191
1935
Grimes-Graeme, R.D.H.Grimes-Graeme, R.D.H.The Origin of the Intrusive Igneous Breccias in the Vicinity of Montreal Quebec.Ph.d. Thesis, Mcgill University, Canada, QuebecDiatreme Breccias
DS1990-0301
1990
Grimley, P.H.Champigny, N., Grimley, P.H.Computer-based reserve estimation and grade control: pratitioners' viewsThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 83, No. 942, October pp. 75-77GlobalGeostatistics, Computers -reserves
DS1990-1037
1990
Grimmeisen, W.Metzner, C., Grimmeisen, W.MONA: a user friendly computer program for calculating the modal mineralogy of rocks from chemical analysesEuropean Journal of Mineralogy, Vol. 2, pp. 735-738GlobalComputer, Program -modal mineralogy
DS2003-0506
2003
Grimmer, J.C.Grimmer, J.C., Ratschbacher, L., McWilliams, M., Franz, L., Gaitzsch, I., et al.When did the ultrahigh-pressure rocks reach the surface? A 207Pb 206 Pb zircon 40Chemical Geology, Vol. 197, 1-4, pp. 87-110.ChinaDabie Shan synorogenic foreland sediments, UHP
DS200412-0728
2003
Grimmer, J.C.Grimmer, J.C., Ratschbacher, L., McWilliams, M., Franz, L., Gaitzsch, I., et al.When did the ultrahigh-pressure rocks reach the surface? A 207Pb 206 Pb zircon 40 Ar 39Ar white mica, Si in white mica, single gChemical Geology, Vol. 197, 1-4, pp. 87-110.ChinaDabie Shan synorogenic foreland sediments UHP
DS201412-0535
2014
Grimmer, S.Lynn, M., Grimmer, S., Ferreira, J.The Motete kimberlite dyke, a new diamond occurrence in Lesotho.GSSA Kimberley Diamond Symposium and Trade Show provisional programme, Sept. 12, title onlyAfrica, LesothoDeposit - Motete
DS200812-0810
2008
Grimmer, S.G.O'Brien, H.E., Legtonen, M.L., Grimmer, S.G., McNulty, K., Peltonen, P., Kontinen, A.Kimberlites in Finland. Geology of kimberlites, carbonatites and alkaline rocks. Seitapera kimberlite and Jormua ophiolite complex.9th. IKC Field Trip Guidebook, CD 58p.Europe, FinlandGuidebook - kimberlites, carbonatites
DS200612-1485
2006
Grimvall, G.Vitos, L., Magyati-Kope, B., Ahuja, R., Kollar, J., Grimvall, G., Johansson, B.Phase transformations between garnet and perovskite phases in the Earth's mantle: a theoretical study.Physics of the Earth and Planetary Interiors, Vol. 156, 1-2, pp. 108-116.MantleLower mantle, majorite, geophysics -seismic
DS201212-0262
2012
Grimwood, B.S.R.Grimwood, B.S.R., Doubleday, N.C., Ljubicic, G.J., Donaldson, S.G., Blangy, S.Engaged acclimatization: towards responsible community based participatory research in Nunavut.Canadian Geographer, in press availableCanada, NunavutCSR - neologism
DS200512-0971
2005
Grinchenko, A.V.Shcherbak, N.P., Artemenko, G.V., Grinchenko, A.V.Age correlation of endogenic processes of the Slave (Canada) and Middle Peri Dneiper (Ukraine) cratons in connection with diamond bearing ability problems.Gems & Gemology, abstracts Mineralogical Journal (Ukraine) Vol. 26, 1, pp. 18-23. *** in English, Vol. 41, 2, Summer p. 194. abstract onlyEurope, Ukraine, CanadaGeochronology, cratons
DS1992-0623
1992
Grinenko, .N.Grinenko, .N., Smolkin, V.F.Isotope composition and content of sulfur in Pechanga-zone ferropicrites and gabbro-wehrlitesGeochemistry International, Vol. 29, No. 4, pp. 30-41RussiaNickel, Pechanga zone
DS1997-0448
1997
Grinenko, L.N.Grinenko, L.N., Lightfoot, P., Krouse, R.Unusual isotopic composition and concentration of carbon in West Greenland mafic volcanicsGeochemistry International, Vol. 34, No. 11, Nov. pp. 958-967GreenlandVolcanics, Geochronology
DS1960-0759
1966
Grinenko, V.A.Vinogradov, A.P., Kropotova, O.I., Orlov, Y.U., Grinenko, V.A.Isotopic Composition of Diamond Crystals and CarbonadoTranslation From Institute Geochemistry And Analytical Chemistry, 3P.Russia, BrazilIsotope
DS1987-0756
1987
Grinenko, V.A.UKhanov, A.V., Ustinov, V.I., Devirts, A.L., Grinenko, V.A.Low serpentinization temperatures of Yakutian kimberlites, as estimated from dat a on oxygen isotopesDoklady Academy of Science USSR, Earth Science Section, Vol. 288, No. 1-6, pp. 163-166YakutiaBlank
DS1987-0759
1987
Grinenko, V.A.Ustinov, V.I., Ukhanov, A.V., Grinenko, V.A., Gavrilov, E.Y.Isotopic composition of oxygen of eclogites from kimberlite pipes Udachnaya and Obnazhennaya. (Technical note). (in Russian)Geochemistry International (Geokhimiya), (Russian), No. 11, November pp. 1637-1641RussiaBlank
DS1989-1533
1989
Grinenko, V.A.Ustinov, V.I., Ukhanov, A.V., Grinenko, V.A.Delta 18O in an olivine-chrome spinelid assemblageGeochemistry International, Vol. 26, No. 9, pp. 128-132RussiaHypabasites, Kimberlite magma
DS1994-1672
1994
Grinenko, V.A.Spetsius, Z.V., Ustinov, V.I., Grinenko, V.A.Variation of oxygen isotope composition during alteration of eclogite To the amorphous state.Doklady Academy of Sciences Acad. Science USSR, Vol. 323, No. 2, June pp. 151-155.RussiaEclogite, Geochronology
DS201112-0126
2011
Grinenko, V.A.Buikin, A.I., Verchovsky, A.B., Grinenko, V.A., Kogarko, L.N.The first stepwise crushing dat a on C, N and Ar isotopic and elemental ratios in Guli carbonatites.Goldschmidt Conference 2011, abstract p.596.Russia, YakutiaMaymecha-Kotuy magmatic complex
DS201605-0816
2016
Grinenko, V.A.Buikin, A.I., Verchovsky, A.B., Kogarko, L.N., Grinenko, V.A., Kuznetsova, O.V.The fluid phase evolution during the formation of carbonatite of the Guli Massif: evidence from the isotope ( C, N, Ar) data.Doklady Earth Sciences, Vol. 466, 2, Feb. pp. 135-137.RussiaCarbonatite

Abstract: The first data on variations of the isotope composition and element ratios of carbon, nitrogen, and argon in carbonatites of different generations and ultrabasic rocks of the Guli massif obtained by the method of step crushing are reported. It is shown that early carbonatite differs significantly from the later ones by the concentration of highly volatile components, as well as by the isotope compositions of carbon (CO2), argon, and hydrogen (H2O). The data obtained allow us to conclude that the mantle component predominated in the fluid at the early stages of formation of rocks of the Guli massif, whereas the late stages of carbonatite formation were characterized by an additional fluid source, which introduced atmospheric argon, and most likely a high portion of carbon dioxide with isotopically heavy carbon.
DS202006-0908
2020
Grinenko, V.S.Afanasiev, V.P., Pokhilenko, N.P., Grinenko, V.S., Kostin, A.V., Malkovets, V.G., Oleinikov, O.B.Kimberlitic magmatism in the south western flank of the Vilui basin. ( pyrope from Kenkeme River catchment) Jurassic-Cretaceous barren kimberlites.Doklady Earth Science, Vol. 490, 2, pp. 51-54.Russiageochronology

Abstract: We have analyzed 141 grains of pyrope from Neogene sediments in a quarry of construction materials, in the Kenkeme River catchment, along its left-side tributary (Chakiya River), about 60 km northwest of Yakutsk city. The mineral chemistry patterns of pyropes are typical of Jurassic-Cretaceous barren kimberlites, like the pipes of Obnazhennaya or Muza, but are uncommon to diamondiferous Middle Paleozoic kimberlites. The results allow identifying the magmatic event and placing time constraints on kimberlite magmatism in the southeastern flank of the Vilui basin, which was part of the Late Jurassic-Early Cretaceous tectonic-magmatic event in northeastern Asia.
DS1998-1176
1998
GrinevPokrovskii, B.G., Andreeva, Vrublevskii, GrinevContamination mechanisms of alkaline gabbroid intrusions in the southern framing of Siberian PlatformPetrology, Vol. 6, No. 3, June, pp. 230-236.Russia, SiberiaGeochronology, Alkaline rocks
DS1991-0615
1991
Grinevitski, G.Z.Grinson, A.S., Grinevitski, G.Z., Volynin, A.F., Perfilov, V.N.Deep tectonic criteria of kimberlite localization in southeastBelomorye.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Voll. 317, No. 5, pp. 1172-1177RussiaTectonics, Kimberlite, genesis
DS201909-2031
2019
Grings, C.D.Colombo, C.L., Vierire Conceicao, R., Grings, C.D.Implications for mantle heterogeneity and diamond preservation derived from RosaRio-6 kimberlite, south of Brazil.Goldschmidt2019, 1p. Poster abstractSouth America, Brazildeposit - RosaRio-6
DS201910-2294
2019
Grings Cadeno, D.Reis Jalowitski, T.L., Grings Cadeno, D., Veira Conceicao, R., Dalla Costa, M.M., Carvalho, A.M.G., Noqueira Neto, J.D.A.Are Juina diamonds, Super Deep diamonds?Goldschmidt2019, 1p. AbstractSouth America, Brazildeposit - Juina

Abstract: Super Deep Diamonds (SDD) are known to form at depths between ~300 and ~1000 km in the Earth’s mantle [1]. These diamonds as well as their minerals, melts and fluid inclusions are rare natural materials from deep Earth. The aim of this study is to indentify and characterize mineral inclusions in diamonds from Juína, Mato Grosso, Brazil, and hence classify them as SDD (or not). Twelve diamonds from four different mining sites of Juína were selected according to their inclusions using an Estereo Microscope. The main diamond features were based on crystallographic faces, shape, degrees of resportion, crystal state and intergrowing [2]. Diamond samples are transparent, colorless and present octahedro, octahedro-tetrahexahedral and tetrahexahedral habits. Some diamonds show trigons with positive and negative relief, and hexagons with negative relief. Four diamonds are heavily resorbed and were classified as "unknowing habits", as their shapes are distorced and fragmented. Moreover, three samples show abrasion on the vertices of the quartenary axes, and the others have distinct degrees of resorption. Some crystals present intergorwth, such as contact twins (macle) in {111} or aggregates. All diamonds have mineral inclusions of different colors. Most inclusions are black and could be carbon spots, oxides or even silicates, such as olivine. Other inclusions are yellow to red, which might indicate garnet. In addition, blue inclusions were observed, and could be sulphides. The next steps consists of Fourier Transform Infrared (FTIR) to determine diamond nitrogen impurities, and Micro-Raman spectroscopy and X-Ray Diffraction analyses using Synchrotron radiation to determine in situ the chemical composition of mineral inclusions.
DS201903-0548
2019
Grings Cedeno, D.Vieira Conceicao, R., Colombo Carniel, L., Jalowitski, T., Gervasoni, F., Grings Cedeno, D.Geochemistry and geodynamic implications on the source of Parana-Etendeka Large Igneous Province evidenced by the late 128 Ma Rosario-6 kimberlite, southern Brazil.Lithos, Vol. 328-329, pp. 130-145.South America, Brazildeposit - Rosario-6

Abstract: The Rosário-6 is a non-diamondiferous hypabyssal kimberlite located above the Rio de la Plata craton and near the south-eastern edge of the Paraná Basin, in southern Brazil. It is petrographically an inequigranular texture, macrocrystal kimberlite, fresh and the groundmass exhibits a microporphyritic texture and round megacrysts of olivine, which are derived from disaggregated mantle xenoliths. Olivine is also present as macrocrysts, microphenocrysts and in the groundmass together with phlogopite and apatite. These microphenocrysts are immersed in a groundmass of olivine, monticellite, phlogopite, CaTiO3-perovskite, apatite, Mg-chromite and Mg-ulvöspinel and melilite. A mesostasis assemblage of phlogopite, melilite, soda melilite, akermanite and calcium carbonate is segregated from the groundmass. Its geochemical signature is similar to those of transitional kimberlites of Kaapvaal Craton, South Africa, and the U-Pb ages of ~ 128 Ma on perovskite reveal that Rosário-6 kimberlite post-dates the main pulse of volcanism in the Paraná-Etendeka Large Igneous Province (LIP). The high Ti content of some minerals, such as Mg-chromite, Mg-ulvöspinel, phlogopite and melilite, and the presence of perovskite suggest a Ti-rich source. The petrographic, geochemical and isotopic data indicate that the Rosário-6 kimberlite source is a depleted mantle metasomatized by H2O-rich fluids, CO2-rich and silicate melts derived from the recycling of an ancient subducted oceanic plate (eclogite) before the South Atlantic opening. Although several authors indicate the influence of Tristan da Cunha plume for the generation of alkaline magmatism associated to the Paraná-Etendeka flood basalts, our data demonstrates that Tristan da Cunha plume has no chemical contribution to the generation of Rosário-6 kimberlite, except by its thermal influence.
DS200412-1622
2004
Grinko, B.N.Rao, D.G., Krishna, K.S., Neprochnov, Yu.P., Grinko, B.N.Satellite gravity anomalies and crustal features of the central Indian Ocean basin.Current Science, Vol. 86, 7, April 10, pp. 948-957.IndiaTectonics, crustal, lineaments
DS1985-0404
1985
Grinrod, A.R.Macdonald, R., Thorpe, R.S., Gaskarth, J.W., Grinrod, A.R.Multi-component Origin of Caledonian Lamprophyres of Northern England.Mineralogical Magazine., Vol. 49, No. 353 PT. 4 SEPTEMBER PP. 485-494.GlobalLamprophyres
DS1975-0091
1975
Grinson, A.S.Grinson, A.S.Detection of Concealed Intrusions from Geologic and Geophysical Dat a by Means of Diagnostic Programs, Case of the Volga-ural Region.Doklady Academy of Science USSR, Earth Science Section., Vol. 222, No. 1-6, PP. 41-43.Russia, UkraineKimberlite, Geophysics
DS1975-1039
1979
Grinson, A.S.Grinson, A.S.Some Structural Features of the Lithosphere in the Eastern Part of the Siberian PlatformDoklady Academy of Sciences USSR, EARTH SCI. SECTION., Vol. 245, No. 1-6, PP. 99-L0L.RussiaBlank
DS1984-0320
1984
Grinson, A.S.Grinson, A.S.Formation and Distribution of Kimberlites in the Eastern Siberian Platform; Structural Control.Izv. Akad. Nauk Sssr Ser. Geol., No. 3, PP. 54-65.Russia, SiberiaGenesis, Location
DS1984-0321
1984
Grinson, A.S.Grinson, A.S.The Forming and Distribution of Kiberlites in the Eastern Part of the Siberian Platform in Relation with its Deep Structural Peculiar Charact Ertistics.Izv. Akad. Nauk Geol. Ser., No. 3, MARCH PP. 54-65.Russia, SiberiaGenesis, Tectonics
DS1984-0322
1984
Grinson, A.S.Grinson, A.S., Dong, C.Y.Kimberlite Magmatism and the Chin a Platform Lithosphere Structure.Doklady Academy of Sciences AKAD. NAUK SSSR., Vol. 276, No. 4, PP. 920-923.Russia, ChinaTectonics, Genesis
DS1986-0310
1986
Grinson, A.S.Grinson, A.S., Dong ZunyingKimberlite volcanism and structure of lithosphere on the ChineseSOURCE[ Doklady Academy of Science USSR, Earth Science SectionDoklady Academy of Science USSR, Earth Science Section, Vol. 276, January, No. 1-6, pp. 64-66ChinaDistribution, Tectonics
DS1991-0615
1991
Grinson, A.S.Grinson, A.S., Grinevitski, G.Z., Volynin, A.F., Perfilov, V.N.Deep tectonic criteria of kimberlite localization in southeastBelomorye.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Voll. 317, No. 5, pp. 1172-1177RussiaTectonics, Kimberlite, genesis
DS1994-1868
1994
Grinson, A.S.Volynin, A.F., Grinson, A.S.Methods of prediction and prospecting of bedrock diamonds in the glacialareas (based geophysical data).10th. Prospecting In Areas Of Glaciated Terrain, pp. 151-152. AbstractGlobalGeomorphology, Geophysics
DS1991-0616
1991
Grisafe, D.A.Grisafe, D.A.Non-energy resources -brief overview -activities in 1990.Brief mention ofdiamondsGeotimes, Vol. 36, No. 2, February, 18-19Russia, Botswana, Malaysia, AustraliaNews item, Diamonds mentioned
DS1960-0508
1964
Griscom, A.Zietz, I., Griscom, A.Geology and Aeromagnetic Expression of the Midcontinent Gravity High.Geological Society of America (GSA) SPECIAL PAPER., No. 76, P. 184. (abstract.).GlobalMid-continent
DS1997-0449
1997
Griselen, M.Griselen, M., Arndt, N.A., Baragar, W.R.A.Plume lithosphere interaction and crustal contamination during formation of Coppermine River basalts, northwest Territories.Canadian Journal of Earth Sciences, Vol. 34, No. 7, July pp. 958=975Northwest TerritoriesMantle plumes, Mackenzie dyke swarms, geochronology, Coppermine River basalts
DS202111-1770
2021
Grishina, S.Grishina, S., Goryainov, S., Oreshonkov, A., Karmanov, N.Micro-Raman study of cesanite ( Ca2Na3(OH)(SO4)3) in chloride segregations from Udachnaya-East kimberlites.Journal of Raman Spectroscopy, 11p. PdfRussiadeposit - Udachnay-East

Abstract: Cesanite (Ca2Na3(OH)(SO4)3), a rare mineral, has been found in a few places restricted to a geothermal field and caves. We report the new occurrence of cesanite in quite different geological site—within sulfate-rich melt inclusions in chloride segregations from kimberlites of Udachnaya-East pipe (Siberia). Two halite generations: ?esanite free and ?esanite-bearing, were distinguished in concentrically zonal segregations according to the results of the mineral and sulfate melt inclusion study by micro-Raman spectroscopy and SEM-EDS. We have applied the Raman spectroscopy and first principles calculations to understand structural and vibrational properties of cesanite daughter mineral in polyphase sulfate inclusions. Polarized spectra provided additional information on the overlapped components of the spectral profile. The Raman spectra of cesanite in the range of OH stretching vibrations are reported for the first time. The study aims to clarify the source of the Na-S-Cl-enrichment in the Udachnaya-East pipe, which is highly discussed.
DS200812-0432
2008
Grishina, S.N.Grishina, S.N., Polozov, A.C., Mazurov, M.P., Titov, A.T.Origin of chloride xenoliths of Udachnaya East kimberlite pipe, Siberia: evidence from fluid and saline melt inclusions.9IKC.com, 3p. extended abstractRussia, SiberiaDeposit - Udcahnaya inclusions
DS200812-0907
2008
Grishina, S.N.Polozov, A.C., Sukhov, S.S., Gornova, M.A., Grishina, S.N.Salts from Udachnaya East kimberlite pipe ( Yakutia, Russia): occurrences and mineral composition.9IKC.com, 3p. extended abstractRussiaDeposit - Udachnaya
DS201312-0338
2013
Grishina, S.N.Grishina, S.N.The world turns over: Hadean-Archean crust mantle evolution.Goldschmidt 2013, AbstractRussia, SiberiaDeposit - Udachnaya
DS201412-0316
2014
Grishina, S.N.Grishina, S.N., Polozov, A.G., Mazurov, M.P., Goryinov, S.V.Genesis of chloride-carbonate segregations of the Udachnaya-East pipe.Doklady Earth Sciences, Vol. 458, 1, pp. 1129-1131.Russia, YakutiaDeposit - Udachnaya-East
DS1998-0048
1998
Grist, A.M.Arne, D.C., Zentilli, M., Grist, A.M., Collins, M.Constraints on the timing of thrusting during the Eurekan Orogeny, Canadian Arctic Archipelago...Canadian Journal of Earth Sciences, Vol. 35, No. 1, Jan. pp. 30-38.Northwest Territories, Ellesmere Island, Sverdrup BasinGeochronology, geothermometry, Tectonics - thrust fault movements
DS1860-0701
1891
Griswold, L.S.Griswold, L.S.The Novaculites of ArkansasAmerican Association Advanced Science, Vol. 39, PP. 248-250. EXTENDED ABSTRACT.United States, ArkansasAlkaline rocks
DS1860-0749
1892
Griswold, L.S.Griswold, L.S.Whetstones and the Novaculites of ArkansawArkansaw Geological Survey Annual Report FOR 1890, Vol. 3, 443P.United States, ArkansasAlkaline rocks
DS2002-0577
2002
Grits, U.Gitelson, A.A., Stark, R., Grits, U., et al.Vegetation and soil lines in visible spectral space: a concept and technique for remote estimation of vegetation fraction.International Journal of Remote Sensing, Vol.23,No.13, July 20, pp. 2537-62.GlobalRemote sensing - not specific to diamonds, Techniques
DS201901-0050
2018
Gritsenko, Y.D.Ogorodova, L.P., Gritsenko, Y.D., Vigasina, M.F., Bychkov, A.Y., Ksenofontov, D.A., Melchakova, L.V.Thermodynamic properties of natural melilites.American Mineralogist, Vol. 103, pp. 1945-1952.Mantlemineralogy

Abstract: In the present study, four samples of natural melilites were characterized using electron microprobe analysis, powder X-ray diffraction, FTIR, and Raman spectroscopy, and their thermodynamic properties were measured with a high-temperature heat-flux Tian-Calvet microcalorimeter. The enthalpies of formation from the elements were determined to be: -3796.3 ± 4.1 kJ/mol for Ca1.8Na0.2(Mg0.7Al0.2Fe2+0.1?)Si2O7, -3753.6 ± 5.2 kJ/mol for Ca1.6Na0.4(Mg0.5Al0.4Fe2+0.1?)Si2O7, -3736.4 ± 3.7 kJ/mol for Ca1.6Na0.4(Mg0.4Al0.4Fe2+0.2?)Si2O7, and -3929.2 ± 3.8 kJ/mol for Ca2(Mg0.4Al0.6)[Si1.4Al0.6O7]. Using the obtained formation enthalpies and estimated entropies, the standard Gibbs free energies of formation of these melilites were calculated. Finally, the enthalpies of the formation of the end-members of the isomorphic åkermanite-gehlenite and åkermanite-alumoåkermanite series were derived. The obtained thermodynamic properties of melilites of different compositions can be used for quantitative modeling of formation conditions of these minerals in related geological and industrial processes.
DS1986-0136
1986
Gritsik, E.P.Chashka, A.I., Palkina, E.Yu., Khrenov, A.Ya., Gritsik, E.P.Morphology and some physical properties of small diamonds.(Russian)Mineral. Sb. (Lvov), (Russian), Vol. 40, No. 2, pp. 81-84RussiaBlank
DS1986-0311
1986
Gritsik, V.V.Gritsik, V.V., Dyakov, A.G.Geochemical aspects of the crystal morphology of diamond.(Russian)Mineral. Kristallogr. I EE Prim. V. Prakt. Geol. Kiev (Russian), Vol. 1986 pp. 132-134RussiaBlank
DS1986-0312
1986
Gritsik, V.V.Gritsik, V.V., D'Yakov, A.G.Some geochemical features of diamond crystal structure.(Russian)In: Mineralogical crystallography and its application to mineral, pp. 132-134RussiaDiamond morphology, Geochemistry
DS1988-0273
1988
Gritsik, V.V.Gritsik, V.V.One of the characteristics of diamonds.(Russian)Mineral. Sb. (L'Vov), (Russian), Vol. 42, No. 2, pp. 76-78RussiaDiamond morphology, Nitrogen
DS1988-0274
1988
Gritsik, V.V.Gritsik, V.V., Dyakov, A.G., Poberezhskiy, V.A.Carbon isotope composition of diamonds from different diamond bearing provinces of the world.(Russian)Mineral. Sbornik (L'Vov), (Russian), Vol. 42, No. 1, pp. 68-70Russia, GlobalGeochronology, Diamonds, Carbon isotope
DS1989-0553
1989
Gritsik, V.V.Gritsik, V.V., Hashchak, M.S., Poberezhskiy, V.A.The insignificant role of parental carbon fractionation during the synthesis of native impact and synthetic diamonds.(Russian)Mineralogischeskiy Sbornik, (L'vov), (Russian), Vol. 43, No. 1, pp. 95-96RussiaMineral chemistry
DS200712-1124
2006
Grizenko, A.G.Vins, V.G., Yeliseyev, A., Chilgrin, S.V., Grizenko, A.G.Natural diamond enhancement: the transformation of intrinsic and impurity defects in the diamond lattice.Gems & Gemology, 4th International Symposium abstracts, Fall 2006, p.120, abstract onlyTechnologyDiamond morphology
DS201112-0680
2011
Groat, L.Millonig, L., Groat, L.Carbonatites and alkaline rocks in the southern Canadian Cordillera.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterCanada, British ColumbiaCarbonatite
DS201112-0681
2011
Groat, L.Millonig, L., Groat, L.Carbonatites and alkaline rocks in the southern Canadian Cordillera.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.99.Canada, British ColumbiaGeochronology
DS201112-0682
2011
Groat, L.Millonig, L., Groat, L.Carbonatites and alkaline rocks in the southern Canadian Cordillera.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.99.Canada, British ColumbiaGeochronology
DS201512-1980
2015
Groat, L.Turner, D., Rivard, B., Groat, L.Visible to shortwave infrared reflectance spectroscopy of rare earth element minerals.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 219-230.TechnologyRare earths
DS201607-1350
2016
Groat, L.Graham, I., Groat, L., Giuliani, G.Gems: bringing the world together,IGC 35th., Session Mineralogy 1 p. abstractTechnologyMineralogy
DS201901-0038
2018
Groat, L.Groat, L.Scientific study of colored gem deposits and modern fingerprinting methods.Gems & Gemology, Sixth International Gemological Symposium Vol. 54, 3, 1p. Abstract p. 277-8.Globalgemstones

Abstract: Most colored gemstones form near the earth’s surface in a wide range of different environments; for example, they can crystallize from igneous magmas or hydrothermal solutions, or via the recrystallization of preexisting minerals during metamorphism. The specific environment determines the types of gem minerals that form, as well as their physical and chemical properties. Field studies of colored gem deposits provide the basis for the scientific understanding of natural gemstone formation and, in turn, the basis for criteria for gem identification. Gem deposits are of scientific interest because they represent unusual geologic and geochemical conditions; for example, emeralds are rare because they require beryllium and chromium (and/or vanadium), which generally travel in very different geochemical circles. Scientists study gem deposits by collecting rock and mineral samples in the field, mapping geological formations and structures, documenting the environment in which the gems occur, and examining the collected samples back in the laboratory. Such examination yields information on the chemical, temperature, and pressure conditions of gem formation, the associated minerals (often found as distinctive inclusions in the gems themselves), and the age of the deposit. Determining the origin of a gem deposit usually requires a small amount of very specific data. The results are published in publicly available peerreviewed publications. Such field studies provide clues that can be used to explore for similar types of gem deposits. Challenges include the remoteness of locations that have not been previously studied by geologists, the small size of deposits that precludes study by large mining companies, and the rarity of the gems themselves. There is much left to do in gem deposit research. For example, despite its growing popularity as a gemstone, there are few studies of gem spinel deposits, especially cobalt-blue spinel (figure 1), for which only one deposit has been studied. To date we know little about what factors control spinel genesis and color. Recently there has been another reason to study gem deposits: gem fingerprinting, in which modern methods are used to obtain characteristic information. This information is then compared to information obtained from stones from known localities to estimate where a stone with no locality information originated. Modern fingerprinting methods analyze the chemistry of the stones (using electron probe microanalysis, isotopic analysis, laser ablation-inductively coupled plasma-mass spectrometry) and/or their solid and fluid inclusions. We know that the chemistry of the stones must reflect the chemistry of the host rock environment; for example, the chromophore in emerald from Lened in Canada is vanadium, and not the typical chromium, because there are no chromium-bearing rocks in the area. With respect to solid inclusions, rubies from Aappaluttoq in Greenland have phlogopite mica inclusions because they recrystallized in a rock at pressures and temperatures where phlogopite is the stable potassium-bearing phase. An example of diagnostic fluid inclusions is the three-phase variety seen in Colombian emeralds (and now also observed elsewhere). New is the use of ICP-MS on fluid inclusions to define part of the fluid assemblage from which the stones were formed; this tells us about the environment of formation, but also may assist in defining a fingerprint for the stone. Where scientific studies require only very specific data, the more data available from stones of known origin, and the more representative those stones are of the full range of compositions and inclusions found in a specific deposit or country of origin, the more accurate the estimation should be. Unfortunately, these data are generally not made public, so every lab doing fingerprinting is essentially working independently, and there is no way to know how accurate their data and the resulting country- or deposit-oforigin estimates are. We also note that a serious problem in origin determination is that some of the best gemstones will be lacking diagnostic inclusions altogether, which then restricts the tools and observations can be used.
DS1997-0757
1997
Groat, L.A.McIntosh, J.M., Groat, L.A.Biological -mineralogical interactions. Bacteria. sulphides, weathering, lichens...Mineralogical Association of Canada, Vol. 25, 230p. $ 45.00GlobalBook - table of contents, Biological -mineralogical interactions
DS200912-0270
2009
Groat, L.A.Groat, L.A., Laurs, B.M.Gem formation, production,and exploration: why gem deposits are rare and what is being done to find them.Elements, Vol. 5, 3, June pp. 153-158.Canada, GlobalOverview
DS201012-0107
2010
Groat, L.A.Chudy, T.C., Groat, L.A.The origin of the tantalum bearing Upper Fir carbonatite, east central British Columbia, Canada: preliminary results.International Mineralogical Association meeting August Budapest, abstract p. 566.Canada, British ColumbiaCarbonatite
DS201012-0806
2010
Groat, L.A.Turner, D., Groat, L.A.Rare earth mineralization at the True Blue property, southern Yukon.International Workshop Geology of Rare Metals, held Nov9-10, Victoria BC, Open file 2010-10, extended abstract pp.47.Canada, YukonAlkalic
DS201112-0189
2011
Groat, L.A.Chudy, T.C., Groat, L.A.Structures in metamorphic carbonatites: an example from the Upper Fir carbonatite east-central British Columbia, Canada.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.20-21.Canada, British ColumbiaUpper Fir
DS201112-0190
2011
Groat, L.A.Chudy, T.C., Groat, L.A.Structures in metamorphic carbonatites: an example from the Upper Fir carbonatite east-central British Columbia, Canada.Peralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.20-21.Canada, British ColumbiaUpper Fir
DS201112-0679
2011
Groat, L.A.Millong, L.J., Gerdes, A., Groat, L.A.U-Pb geochronology and Lu-Hf isotope dat a from meta-carbonatites in the southern Canadian Cordillera.Goldschmidt Conference 2011, abstract p.1474.Canada, British ColumbiaCarbonatite
DS201212-0263
2012
Groat, L.A.Groat, L.A.Gemstones - diamond ( 2 of the pages)American Scientist, Vol. 100, pp. 128-137.GlobalGemstones - overview
DS201212-0475
2012
Groat, L.A.Millonig, L.J., Gerdes, A., Groat, L.A.U Th Pb geochronology of meta-carbonatites and meta-alkaline rocks.Goldschmidt Conference 2012, abstract 1p.Canada, British ColumbiaMagmatism
DS201212-0476
2012
Groat, L.A.Millonig, L.J., Gerdes, A., Groat, L.A.U Th Pb geochronology of meta-carbonatites and meta-alkaline rocks in the southern Canadian Cordillera: a geodynamic perspective.Lithos, Vol. 152, pp. 202-217.Canada, British Columbia, AlbertaCarbonatite
DS201312-0163
2013
Groat, L.A.Chudy, T.C., Groat, L.A.A cathodluminescence study of calcite dolomite microstructures and Cal-Dol geothermometry in highly metamorphosed carbonatites: an example from the Fir carbonatites, east central British Columbia, Canada.GAC-MAC 2013: GS2: Igneous and Metamorphic Petrology and Volcanology, abstract onlyCanada, British ColumbiaCarbonatite
DS201312-0606
2013
Groat, L.A.Millonig, L.J., Gerdes, A., Groat, L.A.The effect of amphibolite facies metamorphism on the U-Th-Pb geochronology of accessory minerals from meta-carbonatites and associated meta-alkaline rocks.Chemical Geology, Vol. 353, pp. 199-209.MantleCarbonatite
DS201312-0883
2013
Groat, L.A.Stern, R.J., Tsujimori, T., Harlow, G., Groat, L.A.Plate tectonic gemstones. ( Jade and Ruby)Geology, in press availableTechnologyGemstones
DS201412-0160
2014
Groat, L.A.Dalsin, M.L., Groat, L.A., Creighton, S., Evans, R.J.The mineralogy and geochemistry of the Wicheeda carbonatite complex, British Columbia, Canada.Ore Geology Reviews, Vol. 64, pp. 523-542.Canada, British ColumbiaCarbonatite
DS201412-0317
2014
Groat, L.A.Groat, L.A.Gem production and potential in Canada. Diamond and other gem stonesGeological Society of America Conference Vancouver Oct. 19-22, 1p. AbstractCanadaGemstones
DS201706-1100
2017
Groat, L.A.Pufahl, P.K., Groat, L.A.Sedimentary and igneous phosphate deposits: formation and exploration: an invited paper. ( carbonatite)Economic Geology, Vol. 112, pp. 483-516.Russia, Kola Peninsula, Europe, Finland, Canada, British Columbiadeposit - Khibina, Fir, Siilinjarvi

Abstract: Phosphorus is the central ingredient in fertilizer that allows modern agriculture to feed the world’s population. This element, also critical in a host of industrial applications, is a nonrenewable resource that is sourced primarily from the phosphatic mineral apatite, hosted in sedimentary and igneous ores. World phosphate resources are estimated by the U.S. Geological Survey at ca. 300,000 Mt, of which 95% are sedimentary and 5% are igneous. Current known USGS reserve estimates are sufficient for a maximum of 200 to 300 years; the exploration and discovery of new resources, enhanced mining technologies, and new technologies aimed at the recovery and recycling of P from sewage and agricultural runoff will all contribute to extending P production. Igneous ores are generally associated with Phanerozoic carbonatites and silica-deficient alkalic intrusions that typically average 5 to 15 wt % P2O5, which can be beneficiated to high-grade concentrates of at least 30 wt % P2O5 with few contaminants. Carbonatites are typically the smallest and youngest parts of a carbonatite-alkaline rock complex that formed during fractional crystallization of a calcic parental alkaline silicate melt, or from liquid immiscibility of a carbonate-rich nephelinite that underwent magmatic fractionation and differentiation during ascent from the mantle source. Fluorapatite generally crystallizes early, near the liquidus, and over a small temperature interval below the apatite saturation temperature that varies strongly with temperature, SiO2 and CaO concentrations, and the aluminosity of the melt. Carbonatite-alkaline rock complexes commonly possess a concentric, zonal structure thought to reflect caldera volcanism. Pathfinder elements in soils, sediments, tills, and vegetation include Nb, rare earth elements (REEs), P, Ba, Sr, F, U, and Th, and in water, F, Th, and U are indicators. Remote sensing techniques with the ability to identify minerals rich in CO3, REEs, and Fe2+ that are characteristic of carbonatites are also important exploration tools that may provide vectors to ore. Sedimentary phosphorite is a marine bioelemental sedimentary rock that contains >18 wt % P2O5. While small peritidal phosphorites formed in Precambrian coastal environments, economically significant upwelling-related phosphorite did not accumulate until the late Neoproterozoic and continued through the Phanerozoic. Coastal upwelling delivered deep, P-rich waters to continental shelves and in epeiric seas to drive phosphogenesis and form the largest phosphorites on Earth. High-grade deposits formed as a result of hydraulic concentration of phosphate grains to form granular beds with minimal gangue. The amalgamation of these beds into decameter-thick, stratiform ore zones is generally focused along the maximum flooding surface, which is a primary exploration target in upwelling-related phosphorite. In addition to P, other elements concentrated in igneous and sedimentary phosphorites are Se, Mo, Zn, Cu, and Cr, which are important agricultural micronutrients. Other saleable by-products include U and REEs. The U concentration in sedimentary phosphorite is generally between 50 and 200 ppm, but can be as high as 3,000 ppm, making it an increasingly important source of U for the nuclear industry. The concentration of REEs in some sedimentary phosphorites is comparable to the world’s richest igneous and Chinese clay-type REE deposits. The source of the dissolved P in upwelling ocean water is ultimately derived from the chemical weathering of continental rocks, the process that links igneous and sedimentary phosphorites through time and space. The covarying temporal relationship of igneous and sedimentary deposits suggests that plate tectonics and the concentration of apatite in a progressively more felsic crust underpins the feedback processes regulating the biogeochemical cycling of P. Critical to the generation of greenfield exploration targets is the recognition that large P deposits emerged in the late Neoproterozoic. The geological environments conducive for exploration can be constrained from an understanding of ore-forming processes by the use of complementary petrological techniques, including fieldwork, petrography, sedimentology, sequence stratigraphy, and geochemistry.
DS201811-2573
2015
Groat, L.A.Giuliani, G., Branquet, Y., Fallick, A.E., Groat, L.A., Marshall, D.Emerald deposits around the world, their similarities and differences.InColor, December pp. 56-69.Globalemeralds
DS202001-0014
2019
Groat, L.A.Groat, L.A.Adding logic to luck: recent advances in coloured stone exploration in Canada.Journal of Gemmology, Vol. 36, pp. 620-633.Canadagemstones
DS202002-0164
2020
Groat, L.A.Belley, P.M., Groat, L.A.Metamorphosed carbonate platforms and controls on the genesis of sapphire, gem spinel, and lapis Lazuli: insight from the Lake Harbour Group, Nunavut, Canada and implications for gem exploration.Ore Geology Reviews, Vol. 116, 10p. PdfCanada, Nunavutgemstones

Abstract: Baffin Island's Lake Harbour Group (LHG), a Paleoproterozoic granulite facies metasedimentary sequence rich in carbonates, contains occurrences of the gemstones sapphire (corundum), spinel (including vivid blue, cobalt-enriched spinel), and lapis lazuli (haüyne-bearing rock). Most occurrences of these gem minerals are uniquely metasedimentary (carbonates and calc-silicate rock), while a few spinel occurrences formed from metasomatic reactions between Si-Al-rich rock (syenogranite or gneiss) and marble. The metasedimentary corundum, spinel, and haüyne occurrences have similar protoliths: primarily dolomitic marls with a high Al/Si relative abundance (interpreted as sandy mud to clay siliciclastic fraction in the protolith). Kimmirut-type sapphire deposits formed via a multi-step metamorphic process under three different and specific P-T conditions. Lapis lazuli formation required the presence of evaporites to provide Na and possibly S for the blue mineral haüyne. In addition to high Al/Si calc-silicate rocks, spinel also occurs in impure dolomitic marbles with very low K/Al. Potential for Kimmirut-type sapphire deposits is expected to be restricted to metacarbonate sequences proximal to the thrust fault separating the LHG from the Narsajuaq Arc, where retrograde upper amphibolite facies mineralization is most pervasive. Spinel and Kimmirut-type sapphire deposits are expected to be found in dolomitic marble sequences rich in calc-silicate layers. The potential occurrence of lapis lazuli is more difficult to predict but deposits could be identified thanks to large geographical footprints and their color. Similar gem occurrences or deposits to those in the LHG may be found in other metacarbonate-bearing terranes with similar metamorphic conditions (and for Kimmirut-type sapphire, a similar metamorphic history). Aerial hyperspectral and photographic surveys are well-suited to gemstone exploration on southern Baffin Island thanks to excellent rock exposure with minimal sediment or plant/lichen cover. Spectral mapping of dolomite-, diopside-, phlogopite-, and scapolite-rich domains in LHG metacarbonate sequences using airborne hyperspectral data is expected to provide exploration targets. Remote sensing exploration could be used in other metacarbonate-bearing, upper amphibolite to granulite facies metamorphic terranes found in polar climates, arid climates, or at high elevation in mountainous regions where such rocks are well exposed with minimal vegetative cover.
DS202003-0340
2019
Groat, L.A.Giuliani, G., Groat, L.A.Geology of corundum and emerald gem deposits: a review.Gems & Gemology, Vol. 55, 4, pp. 464-511.Africa, Madagascar, Zambia, Asia, Sri Lanka, South America, Colombiaemerald

Abstract: The great challenge of geographic origin determination is to connect the properties and features of individual gems to the geology of their deposits. Similar geologic environments can produce gems with similar gemological properties, making it difficult to find unique identifiers. Over the last two decades, our knowledge of corundum and emerald deposit formation has improved significantly. The mineral deposits are classically separated into primary and secondary deposits. Primary corundum deposits are subdivided into two types based on their geological environment of formation: (1) magmatic and (2) metamorphic. Magmatic deposits include gem corundum in alkali basalts as in eastern Australia, and sapphire in lamprophyre and syenite as in Montana (United States) and Garba Tula (Kenya), respectively. Metamorphic deposits are divided into two subtypes (1) metamorphic deposits sensu stricto (in marble; mafic and ultramafic rocks, or M-UMR), and (2) metamorphic-metasomatic deposits characterized by high fluid-rock interaction and metasomatism (i.e., plumasite or desilicated pegmatites in M-UMR and marble, skarn deposits, and shear zonerelated deposits in different substrata, mainly corundum-bearing Mg-Cr-biotite schist). Examples of the first subtype include the ruby deposits in marble from the Mogok Stone Tract or those in M-UMR from Montepuez (Mozambique) and Aappaluttoq (Greenland). The second subtype concerns the sapphire from Kashmir hosted by plumasites in M-UMR. Secondary corundum deposits (i.e., present-day placers) result from the erosion of primary corundum deposits. Here, corundum is found in the following types of deposits: eluvial (derived by in situ weathering or weathering plus gravitational movement), diluvial (scree or talus), colluvial (deposited at the base of slopes by rainwash, sheetwash, slow continuous downslope creep, or a combination of these processes), and alluvial (deposited by rivers). Today, most sapphires are produced from gem placers related to alkali basalts, as in eastern Australia or southern Vietnam, while placers in metamorphic environments, such as in Sri Lanka (Ratnapura, Elahera) and Madagascar (Ilakaka), produce the highest-quality sapphires. The colluvial Montepuez deposit in Mozambique provides a huge and stable supply of clean and very high-quality rubies. Primary emerald deposits are subdivided into two types based on their geological environment of formation: (1) tectonic-magmatic-related (Type I) and (2) tectonic-metamorphic-related (Type II). Several subtypes are defined and especially Type IA, hosted in M-UMR, which accounts for about 70% of worldwide production (Brazil, Zambia, Russia, and others). It is characterized by the intrusion of pegmatites or quartz veins in M-UMR accompanied by huge hydrothermal fluid circulation and metasomatism with the formation of emerald-bearing desilicated pegmatite (plumasite) and biotite schist. Type IB in sedimentary rocks (China, Canada, Norway, Kazakhstan, and Australia) and Type IC in granitic rocks (Nigeria) are of minor importance. The subtype Type IIA of metamorphic deposits is related to hydrothermal fluid circulation at high temperature, in thrust fault and/or shear zones within M-UMR of volcano-sedimentary series, such as at the Santa Terezinha de Goiás deposit in Brazil. The subtype Type IIB is showcased by the Colombian emerald deposits located in the Lower Cretaceous black shales of the Eastern Cordillera Basin. These are related to the circulation of hydrothermal basinal fluids in black shales, at 300330°C, that dissolved evaporites in (1) thrust and tear faults for the deposits of the western emerald zone (Yacopi, Coscuez, Muzo, Peñas Blancas, Cunas, and La Pita mines) and (2) a regional evaporite level intercalated in the black shales or the deposits of the eastern emerald zone (Gachalá, Chivor, and Macanal mining districts). Secondary emerald deposits are unknown because emerald is too fragile to survive erosion and transport in rivers.
DS202003-0341
2019
Groat, L.A.Groat, L.A., Giuilani, G.,, Stone-Sundberg, J., Sun, Z., Renfro, N.D., Palke, A.C.A review of analytical methods used in geographic origin determination of gemstones.Gems & Gemology, Vol. 55, 4, pp. 512-535.Globalemerald, sapphire

Abstract: Origin determination is of increasing importance in the gem trade. It is possible because there is a close relationship between the geological environment of formation and the physical and chemical properties of gemstones, such as trace element and isotopic compositions, that can be measured in the laboratory using combinations of increasingly sophisticated instrumentation. Origin conclusions for ruby, sapphire, and emerald make up the bulk of demand for these services, with growing demand for alexandrite, tourmaline, and spinel. However, establishing origin with a high degree of confidence using the capabilities available today is met with varying degrees of success. Geographic origin can be determined with a high level of confidence for materials such as emerald, Paraíba-type tourmaline, alexandrite, and many rubies. For some materials, especially blue sapphire and some rubies, the situation is more difficult. The main problem is that if the geology of two deposits is similar, then the properties of the gemstones they produce will also be similar, to the point where concluding an origin becomes seemingly impossible in some cases. Origin determination currently relies on a combination of traditional gemological observations and advanced analytical instrumentation.
DS201907-1552
2019
Grobbelaar, G.Jacob, J., Grobbelaar, G.Onshore and nearshore diamond mining on the south-western coast of Namibia: recent activities and future exploration techniques.Journal of Gemmology, Vol. 36, 6, pp. 524-533.Africa, Namibiamining
DS2002-0380
2002
Grobe, H.Diepenbroek, M., Grobe, H., Reinke, M., Schindler, U., SchlitzerPANGEA - an information system for environmental sciencesComputers and Geosciences, Vol. 28, 10, pp.1201-10.GlobalComputers - programs
DS2000-0259
2000
Grobe, M.Eccles, D.R., Grunsky, E.C., Grobe, M., Weiss, J.Structural emplacement model for kimberlitic diatremes in northern AlbertaAlberta Energy and Utilities Board and Alberta Geological Survey, Report, 116p.AlbertaStructure - model
DS2000-0260
2000
Grobe, M.Eccles, D.R., Grunsky, E.C., Grobe, M., Weiss, J.Structural emplacement model for kimberlitic diatremes in AlbertaGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Calgary May 2000, 1p.AlbertaStructure -, Deposit - Buffalo Hills area
DS2000-0261
2000
Grobe, M.Eccles, D.R., Grunsky, E.G., Grobe, M., Weiss, J.Structural emplacement model for kimberlitic diatremes in northern Alberta28th. Yellowknife Geoscience Forum, p. 22-24.abstractAlbertaStructure, Buffalo Hills area
DS2001-0882
2001
Grobe, W.Pana, D., Waters, J., Grobe, W.GIS compilation of structural elements in northern AlbertaAlberta Geological Survey, www.ags.gov.ab.ca, ESR 01-01, Release 1.0 $ 20.AlbertaTectonics, structure
DS201605-0910
2016
Grober, E.Tukker, H., Holder, A., Swarts, B., Van Strijp, T., Grober, E.The CCUT black cave design for the Culli nan diamond mine.Diamonds Still Sparkling SAIMM 2016 Conference, Mar. 14-17, pp. 57-70.Africa, South AfricaDeposit - Cullinan
DS2003-1169
2003
Grobety, B.Risold, A.C., Trommsdorff, V., Grobety, B.Morphology of oriented ilmenite inclusions in olivine from garnet peridotites ( CentralEuropean Journal of Mineralogy, Vol. 15, 2, pp. 289-94.SwitzerlandPeridotites
DS200412-1672
2003
Grobety, B.Risold, A.C., Trommsdorff, V., Grobety, B.Morphology of oriented ilmenite inclusions in olivine from garnet peridotites ( Central Alps, Switzerland).European Journal of Mineralogy, Vol. 15, 2, pp. 289-94.Europe, SwitzerlandPeridotite
DS2003-0333
2003
Grobety, B.H.Di Pierro, S., Gnos, E., Grobety, B.H., Armbruster, T., Bernasconi, S.M., Ulmer, P.Rock forming moissanite ( natural a-silicon carbide)American Mineralogist, Vol. 88, pp. 1817-21.Aegean SeaGeochemistry
DS200412-0450
2003
Grobety, B.H.Di Pierro, S., Gnos, E., Grobety, B.H., Armbruster, T., Bernasconi, S.M., Ulmer, P.Rock forming moissanite ( natural a-silicon carbide).American Mineralogist, Vol. 88, pp. 1817-21.TechnologyGeochemistry
DS201605-0911
2016
Grobler, E.Tukker, H., Marsden, H., Holder, A., Swarts, B., Van Strijp, T., Grobler, E., Engelbrecht, F.Koffiefontein diamond mine sublevel cave design.Diamonds Still Sparkling SAIMM 2016 Conference, Mar. 14-17, pp. 129-142.Africa, South AfricaDeposit - Koffiefontein
DS201709-2066
2016
Grobler, E.Tukker, H., Holder, A., Swarts, B., van Strijp, T., Grobler, E.The CCUT block cave design for Culli nan diamond mine.South African Institute of Mining and Metallurgy, Vol. 116, 8, pp. 715-723.Africa, South Africadeposit - Cullinan
DS1989-0554
1989
Grobler, N.J.Grobler, N.J., Van der Westhuizen, W.A., Tordiffe, E.A.W.The Sodium Group, South Africa: reference section for Late Archean- early Proterozoic cratonic cover sequencesAustralian Journal of Earth Sciences, Vol. 36, pp. 41-64. Database # 17953South AfricaProterozoic, Kaapvaal Craton
DS201412-0318
2014
Grocholski, B.Grocholski, B.Making mantle melt analogs more accurate.Geophysics Science* notation also in American Mineralogist, Vol. 345, 6200 pp. 1017-MantleGlass - silicate melts
DS201412-0319
2014
Grocholski, B.Grocholski, B.Unravelling ring woodite hydration in mantle.Science , Vol. 346, 6207, pp. 311-312.MantleRingwoodite
DS201412-0320
2014
Grocholski, B.Grocholski, B.Constructing geochemical geometry.Science, Vol. 346, 6210 Nov. 7, pp. 713-714.MantleGeochemistry
DS201502-0060
2015
Grocholski, B.Grocholski, B.A lower mantle water cycle component.Science, Vol. 347, 6220, Jan. 23, pp. 385-386.MantleWater
DS201509-0397
2015
Grocholski, B.Grocholski, B.Unlocking Earth's ancient magnetic past.Science, Vol. 349, 6247, pp. 490-492.MantlePaleomagnetism

Abstract: The magnetic field protects Earth's surface from deadly cosmic radiation and provides clues about the planet's interior. Tarduno et al. found that some of the oldest minerals on Earth, Jack Hills zircons, preserved a record of a magnetic field over 4 billion years ago (see the Perspective by Aubert). Earth's magnetic field appears to have been fully operational a mere few hundred million years after the planet formed. This suggests an early start for plate tectonics and an ancient cosmic radiation shield that was important for habitability.
DS201510-1769
2015
Grocholski, B.Grocholski, B.Broadening the source for hotspots.Science, Vol. 349, 6255, Sept. 25, pp. 1501-1502.MantleHotspots
DS201511-1836
2015
Grocholski, B.Grocholski, B.Coupled constraints on core formation.Science, Vol. 350, 6258, Oct. 16, pp. 289-290.MantleChemistry
DS201602-0207
2016
Grocholski, B.Grocholski, B.New crustal clues from old rocks.Science, Vol. 352, 6271, pp. 350-351.MantleGeochronology
DS201607-1297
2016
Grocholski, B.Grocholski, B.Managing metal the core left behind.Science, Vol. 352, 6291, pp. 1289-1290.MantleGeophysics
DS201909-2043
2019
Grocholski, B.Grocholski, B.Super-old mantle plumes.Science, Vol. 365, 6455, p. 770.Mantleplate tectonics

Abstract: Plate tectonics on Earth are linked to the dynamics of the interior today. However, the interior dynamics in the distant past are a far greater mystery because of the subduction of surface rock. Wang et al. analyzed 3.5-billion-year-old rocks in China and discovered the oldest geochemical evidence of mantle plume magmatism along with high mantle temperatures. The rocks also appear to record chemical heterogeneity and may be evidence of convection in the deep mantle 3.5 billion years ago.
DS202002-0190
2020
Grocholski, B.Grocholski, B.Synthesizing single-layer diamond: Carbon allotropes of diamond and graphene.Science, Vol. 367, 6476, p. 402.Globalcarbon

Abstract: The carbon allotropes of diamond and graphene have different types of bonding that lead to their exceptional properties. Bakharev et al. pull off the impressive trick of making a monolayer carbon film that is diamond-like in its bonding. The authors accomplish this by attaching fluorine atoms to the carbon film, creating “F-diamane.” Diamane is a long-sought-after, but challenging to make, material that should have useful properties. F-diamane may find use in a variety of applications, from microelectronics as a semiconductor to a seed material for growing single-crystal diamond films.
DS1992-1381
1992
Grocholsky, A.L.Shemenda, A.I., Grocholsky, A.L.Physical modelling of lithosphere subduction in collision zonesTectonophysics, Vol. 216, pp. 273-290GlobalLithosphere, Mantle, Model
DS1994-0668
1994
Grocott, J.Grocott, J., Brown, M., Dallmeyer, R.D., Taylor, G.K., TreloarMechanisms of continental growth in extensional arcs: an example from the Andean plate boundary zoneGeology, Vol. 2, No. 5, May pp. 391-393Andes, ChileTectonics, Arcs
DS1996-0323
1996
Grocott, J.Dallmeyer, R.D., Brown, M., Grocott, J., et al.Mesozoic magmatic and tectonic events within the Andean plate boundaryzone, North Chile: constraints 40Ar/39ArJournal of Geology, Vol. 104, No. 1, pp. 19-40ChileTectonics, Geochronology
DS2002-0501
2002
Grocott, J.Garde, A.A., Hamilton, M.A., Chadwick, B., Grocott, J., McCaffrey, K.J.W.The Ketilidian orogen of South Greenland: geochronology, tectonics, magmatism andCanadian Journal of Earth Science, Vol.39,5, May, pp.765-93.GreenlandTectonics
DS200412-0729
2004
Grocott, J.Grocott, J., McCaffrey, K.J.W., Taylor, G., Tikoff, B.Vertical coupling and decoupling in the lithosphere.Geological Society of London Special Paper, No. 227, 352p. $140.MantleBook - lithosphere
DS200512-0371
2004
Grocott, J.Grocott, J., McCaffrey, K.J.W., Taylor, G., Tikoff, B.Vertical coupling and decoupling of the lithosphere.Geological Society of London , Special Publication 227, 352p. $134.Book - mantle, orogeny, subduction
DS1993-1359
1993
Grodnitskii, L.L.Rybakov, S.I., Grodnitskii, L.L., et al.Metallogenic epochs and evolution of ore forming processesGeology of Ore Deposits, (QE390 G4), Vol. 35, No. 5, pp. 329-336RussiaMetallogeny
DS1940-0047
1942
Grodzinski, P.Grodzinski, P.Diamond and Gemstone Industrial ProductionLondon: N.a.g. Press, 256P.GlobalDrilling, Cutting, Production, Kimberley
DS1950-0101
1952
Grodzinski, P.Grodzinski, P.Hard to SawThe Gemologist., Vol. 21, No. 252, JULY, P. 122.AustraliaDiamond Cutting
DS1950-0133
1953
Grodzinski, P.Grodzinski, P.Diamond TechnologyLondon: N.a.g. Press Ltd., 840P.GlobalKimberlite
DS200612-0502
2006
Groebner, N.Groebner, N., Kohlstedt, D.L.Deformation induced metal melt networks in silicates: implications for core mantle interactions in planetary bodies.Earth and Planetary Science Letters, Vol. 245, 3-4, May 30, pp. 571-580.MantleMelting
DS1860-0208
1873
Groeger, F.Groeger, F.Das Vorkommen der Diamanten in SuedafrikaVerhandlungen der kk geologischen Reichsanstalt (WIEN), No. 17, PP. 310-312.Africa, South Africa, Cape ProvinceGeology
DS1860-0295
1878
Groeger, F.Groeger, F.Das Vorkommen der Diamanten in SuedafrikaVerhandlungen der kk geologischen Reichsanstalt (WIEN), Vol. 6, No. 17, PP. 403-404.Africa, South AfricaGeology
DS1860-0750
1892
Groen, N.A.Groen, N.A.Diamonds and the Diamond IndustryCape Town: Townshend, Taylor And Snashall, 8P.Africa, South Africa, Griqualand WestDiamond Cutting And Polishing
DS1991-0617
1991
Groenewald, P.B.Groenewald, P.B., Gratham, G.H., Watkeys, M.K.Geological evidence for a Proterozoic to Mesozoic link between southeastern Africa and Dronning Maud Land, AntarcticaJournal of the Geological Society of London, Vol. 148, pp. 1115-1123Africa, AntarcticaCraton, Lithostratigraphy
DS200512-0350
2004
Groenewald, P.B.Goleby, B.R., Blewett, R.S., Korsch, R.J., Champion, D.C., Cassidy, K.F., Jones, L.E., Groenewald, P.B., Henson, P.Deep seismic reflection profiling in the Archean northeastern Yilgarn Craton: implications for crustal architecture and mineral potential.Tectonophysics, Vol. 388, 1-4, pp. 119-133.AustraliaGeophysics - seismics, not specific to diamonds
DS1995-0253
1995
Groenwald, G.H.Cairncross, B., Groenwald, G.H., Rudbidge, B.S., Von BrunnKaroo sedimentology and paleontologyGeological Society of South Africa, Cent. Geocongress, Guide B3, 49p.South AfricaSedimentology, Karoo Supergroup
DS1940-0174
1948
Grogan, R.M.English, R.M., Grogan, R.M.Omaha Pool and Mica Peridotite Intrusives, Gallatin County, illinois.Illinois Geological Survey Report Inv., No. 130, PP. 189-212.GlobalRelated Rocks
DS1940-0175
1948
Grogan, R.M.English, R.M., Grogan, R.M.Omaha Pool and Mica Peridotite Intrusives Gallatin County, Illinois.Illinois Geological Survey Report Inv., No. 130, PP. 189-212.United States, Illinois, Kentucky, Great LakesBlank
DS200712-0386
2006
Grohmann, C.H.Grohmann, C.H., Riccomini, C., Machado Alves, F.SRTM based morphotectonic analysis of the Pocos de Caldas alkaline Massif, southeastern Brazil.Computers & Geosciences, Vol. January pp. 10-19.South America, BrazilGeomorphology - alkaline
DS1975-0397
1976
Grohmann, H.Rooijen, P. VAN, Grohmann, H.Sketch Map, Showing the Results of the Magnetic Survey of Pipe 307, Resetilemla ( Maseru).Lesotho Department of Mines And Geology, PROJECT LES73/021, MAP 1: 500, 000.LesothoKimberlite, Geophysics, Prospecting
DS1999-0269
1999
Grokhovskaya, T.L.Grokhovskaya, T.L., Sharkov, E.V., Tevelv, A.V.Petrology of the Mount General skaya layered intrusion, Kola PeninsulaPetrology, Vol. 7, No. 5, pp. 509-526.Russia, Kola PeninsulaLayered intrusion - not specific to diamonds
DS1997-0731
1997
Groleau, P.Marcotte, D., Groleau, P.A simple and robust log normal estimatorMath. Geol, Vol. 29, No. 8, Nov. pp. 993-1010GlobalComputer, Lognormal, geostatistics
DS202203-0354
2022
Grolimund, D.Krstulovic, M., Rosa, A.D., Sanchez, D.F., Libon, L., Albers. C., Merkulova, M., Grolimund, D., Irifune, T., Wilke, M.Effect of temperature on the densification of silicate melts to lower Earth's mantle.Physics of the Earth and Planetary Interiora, 13p. PdfMantlemelting

Abstract: Physical properties of silicate melts play a key role for global planetary dynamics, controlling for example volcanic eruption styles, mantle convection and elemental cycling in the deep Earth. They are significantly modified by structural changes at the atomic scale due to external parameters such as pressure and temperature or due to chemistry. Structural rearrangements such as 4- to 6-fold coordination change of Si with increasing depth may profoundly influence melt properties, but have so far mostly been studied at ambient temperature due to experimental difficulties. In order to investigate the structural properties of silicate melts and their densification mechanisms at conditions relevant to the deep Earth's interior, we studied haplo basaltic glasses and melts (albite-diopside composition) at high pressure and temperature conditions in resistively and laser-heated diamond anvil cells using X-ray absorption near edge structure spectroscopy. Samples were doped with 10 wt of Ge, which is accessible with this experimental technique and which commonly serves as a structural analogue for the network forming cation Si. We acquired spectra on the Ge K edge up to 48 GPa and 5000 K and derived the average Ge-O coordination number , and bond distance as functions of pressure. Our results demonstrate a continuous transformation from tetrahedral to octahedral coordination between ca. 5 and 30 GPa at ambient temperature. Above 1600 K the data reveal a reduction of the pressure needed to complete conversion to octahedral coordination by ca. 30 . The results allow us to determine the influence of temperature on the Si coordination number changes in natural melts in the Earth's interior. We propose that the complete transition to octahedral coordination in basaltic melts is reached at about 40 GPa, corresponding to a depth of ca. 1200 km in the uppermost lower mantle. At the core-mantle boundary (2900 km, 130 GPa, 3000 K) the existence of non-buoyant melts has been proposed to explain observed low seismic wave velocity features. Our results highlight that the melt composition can affect the melt density at such extreme conditions and may strongly influence the structural response.
DS202106-0921
2021
Groller, E.Antonini, A., Ganuza, M.L. , Ferracutti, G., Gagiulo, M.F., Matkovic, K., Groller, E., Bjerg, E.A., Castro, S.M.Spinel web: an interactive web application for visualizing the chemical composition of spinel group minerals. ** not specific to diamondsEarth Science Informatics, Vol. 14, pp. 521-528. pdfMantletectonics

Abstract: The spinel group minerals provide useful information regarding the geological environment in which the host rocks were formed, constituting excellent petrogenetic indicators, and guides in the search for mineral deposits of economic interest. In this article, we present the Spinel Web, a web application to visualize the chemical composition of spinel group minerals. Spinel Web integrates most of the diagrams commonly used for analyzing the chemical characteristics of the spinel group minerals. It incorporates parallel coordinates and a 3D representation of the spinel prisms. It also provides coordinated views and appropriate interactions for users to interact with their datasets. Spinel Web also supports semi-automatic categorization of the geological environment of formation through a standard Web browser.
DS2001-0415
2001
Grollimund, B.Grollimund, B., Zoback, M.D.Did deglaciation trigger intraplate seismicity in the New Madrid seismic zone?Geology, Vol. 29, No. 2, Feb. pp. 175-8.Missouri, Arkansas, Tennessee, KentuckyTectonics, Lithosphere - seismicity
DS2002-1797
2002
Grollimund, B.Zoback, M.D., Townend, J., Grollimund, B.Steady state failure equilibrium and deformation of intraplate lithosphereInternational Geology Review, Vol. 44, No. 5, pp. 383-401.California, Missouri, mantleGeothermometry, heat flow, Geophysics - New Madrid seismic zone
DS201412-1007
2014
Gromilov, S.Yelisseyev, A., Khrenov, A., Afanasiev, V., Pustavarov, V., Gromilov, S., Panchenko, A., Poikilenko, N., Litasov, K.Luminesence of impact diamonds from the Popigai astrobleme.V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Sciences International Symposium Advances in high pressure research: breaking scales and horizons ( Courtesy of N. Poikilenko), Held Sept. 22-26, 2p. AbstractRussia, SiberiaDiamond luminescence
DS201509-0439
2015
Gromilov, S.Yelisseyev, A., Khrenov, A., Afanasiev, V., Pustovarov, V., Gromilov, S., Panchenko, A., Pokhilenko, N., Litasov, K.Luminescence of natural carbon nanomaterial: impact diamonds from the Popigai crater.Diamond and Related Materials, Vol. 58, pp. 69-77.RussiaDeposit - Popigai

Abstract: Impact diamonds (IDs) from the Popigai crater are aggregates of nanoparticulate graphite and cubic and hexagonal diamonds. IDs demonstrate broad-band emissions at 3.05, 2.8, 2.3 and 2.0 eV, which are associated with structural defects and are similar to those in detonation ultra-dispersed diamonds and CVD diamond films. A doublet with components at 1.7856 and 1.7892 eV in some ID samples is related to R1,2 lines of Cr3 + ions in corundum inclusions. The presence of N3, H3, NV0 and NV? vibronic systems in some of the ID samples shows that (i) there is nitrogen impurity and (ii) samples underwent high temperature annealing that promoted vacancies and nitrogen diffusion and defect aggregation. The luminescence decay fits with a sum of two exponential components: lifetime of the fast one is in the 5 to 9 ns range. Parameters of the traps responsible for broad thermoluminescence peaks at 148, 180, 276 and 383 K were estimated.
DS202002-0221
2020
Gromilov, S.Yelisseyev, A., Gromilov, S., Afanasiev, V., Sildos, I., Kiisk, V.Effect of lonsdaleite on the optical properties of impact diamonds.Diamonds & Related Materials, Vol. 101, 107640, 13p. PdfRussiaPopigai

Abstract: The special features of impact diamonds are the orientation of the nanosized grains relative to each other, the presence of hexagonal diamond (lonsdaleite, L) in a large part of the samples and the increased wear resistance. Using Raman spectroscopy and XRD, two groups of translucent samples of Popigai impact diamonds (PIDs) were selected: with and without lonsdaleite and the effect of lonsdaleite on the optical properties of the samples was studied. In all L-containing PIDs there is a strong absorption band of about 1230 cm-1 in the one-phonon region, in the mid-IR. The absorption edge is blurred and described by the Urbach rule. The estimated value of Eg ~4 eV for L is consistent with the first principles calculations. Impurity nitrogen is found only in L-free PIDs: There are signals from nitrogen-vacancy complexes in the photoluminescence (PL) spectra. Variations in the number of nitrogen atoms (N = 1 to 4) in the structure of these centers indicate significant variations in the parameters of PID annealing. L-containing PIDs are characterized by large strains in the lattice and, as a consequence, there are problems with the defect diffusion. The narrow lines in PL spectra, uncommon for diamond, can be the result of several orders of magnitude higher concentrations of impurities in PIDs formed during the solid-phase transition. The broadened peaks of 180, 278 and 383 K are distinguishable in the curves of thermostimulated luminescence (TSL) for L-free PIDs, but in the presence of L the TSL glow becomes continuous as in natural IaA-type diamonds with platelets. In general, lonsdaleite deteriorates the optical properties of impact diamonds and makes it difficult to create certain types of impurity-vacancy complexes for different applications.
DS201610-1919
2016
Gromilov, S.A.Yelisseyev, A.P., Afansiev, V.P., Panchenko, A.V., Gromilov, S.A., Kaichev, V.V., Sarasev, A.A.Yakutites: are they impact diamonds from the Popigai crater?Lithos, in press available 14p.RussiaImpact diamonds

Abstract: Yakutites are coarse (up to 15 mm or larger) aggregates dispersed for more than 500 km around the Popigai meteorite crater. They share many features of similarity with impact diamonds found inside the crater, in elemental and phase compositions, texture, and optical properties as revealed by X-ray photoelectron spectroscopy, X-ray diffraction, and optical spectroscopy (Raman, absorption, luminescence and microscopic) studies. The N3 vibronic system appearing in the luminescence spectra of Popigai impact diamonds (PIDs) indicates a presence of nitrogen impurity and a high-temperature annealing of diamonds that remained in the crater after solid-phase conversion from graphite. Yakutites lack nitrogen-vacancy centers as signatures of annealing, which may indicate quenching at the time of ejection. Thus, both PIDs and yakutites originated during the Popigai impact event and yakutites were ejected to large distances.
DS201810-2325
2018
Gromilov, S.A.Gromilov, S.A., Afanasiev, V.P., Poikhilenko. N.P.Moissanites of the Popigai astrobleme.Doklady Earth Sciences, Vol. 481, 2, pp. 997-999.Russiamoissanite

Abstract: Moissanites were found in tagamites of the Popigai meteorite crater along with impact diamonds. We have studied 55 samples including 49 individual polytypes and six intergrowths. The numbers of 6H, 15R, 4H, 6H/15R, and 6H/4H polytypes are 82, 7, 5, 4, and 2%, respectively. By the assemblage of polytypes, the moissanites of the Popigai astrobleme are distinct from kimberlite moissanites, as well as from synthetic SiC, which is characterized by the absence of the 4H polytype and the presence of more diverse inclusions (including Fe-bearing). The Popigai astrobleme is one of few objects with reliable natural moissanite. Technogenic contamination is excluded, since any researcher can find this mineral in tagamites.
DS201812-2901
2018
Gromilov, S.A.Yelisseyev, A.P., Afanasyev, V.P., Gromilov, S.A.Yakutites from the Popigai meteorite crater.Diamond & Related Materials, Vol. 89, pp. 10-17.Russiameteorite

Abstract: For the first time, 60 large diamond aggregates were found inside the Popigai meteorite crater during washing of alluvial deposits along the Dogoi river crossing the crater. These aggregates are similar in appearance to yakutites from the placers of Northern Yakutia (YPY), and we regard them as yakutites from the Popigai crater (YPC). The structure and optical properties of Popigai impact diamonds from the impact melt rocks (tagamites) in the crater (PIDT) and yakutites YPC/YPY were compared in detail. In all these cases, a polycrystalline structure consisting of nanoscale grains of cubic and twinned cubic diamond (lonsdaleite) was found. This is the result of a solid-phase graphite-diamond transition due to an impact event 35?million?years ago. The diamond aggregates show the following features: a red shift of the short-wave edge of the transmission, broadening of the diamond Raman peaks, signals from other diamond polytypes and numerous inclusions of other minerals in the Raman spectra, and a dominant broadband photoluminescence (PL). PL in the N3 system associated with N3V centers in PIDT diamonds indicates a high-temperature annealing of these aggregates with resulting aggregation of impurities during the prolonged cooling of large impact melt pockets and pools. It is assumed that some of the impact diamonds were ejected from the crater during the impact event and experienced rapid cooling. Some of these diamonds fell back into the crater (YPC yakutites), others have been deposited outside the crater and displaced during erosion (YPY yakutites). Difference in size and shape between the PIDTs and yakutites YPC/YPY is due to the difference in size of original graphite flakes or aggregates and/or due to the fundamentally different technologies of diamond extraction.
DS1995-0166
1995
Gromme, S.Bogue, S.W., Gromme, S., Hillhouse, J.W.Paleomagnetism, magnetic anisotropy and mid-Cretaceous paleolatitude of Duke Island Alaska ultramafic complexTectonics, Vol. 14, No. 5, October pp. 1133-1152AlaskaPaleomagnetism, Duke Island Complex
DS2001-0627
2001
Gromov, M.D.Kosheev, A.P., Gromov, M.D., Mohaptra, R.K.History of trace gases in presolar diamonds inferred from ion-implanted experiments.Nature, No. 6847, Aug. 9, pp. 615-6.GlobalDiamond - experimental
DS201412-0563
2014
Groner, E.Mayer, B., Jung, S., Romer, R.,Pfander, J., Klugel, A., Pack, A., Groner, E.Amphibole in alkaline basalts from intraplate settings: implications for the petrogenesis of alkaline lavas from the metasomatised lithospheric mantle.Contributions to Mineralogy and Petrology, Vol. 167, 3, pp. 1-22.MantleMetasomatism
DS1987-0259
1987
Gronlands Geologiske UndersogelseGronlands Geologiske UndersogelseApatite mineralization in carbonatite and ultramafic intrusions inGreenlandGronlands Geologiske Undersogelse, approx. 200pGreenlandCarbonatite, Apatite
DS1995-0691
1995
Gronlands Geologiske UndersogelseGronlands Geologiske UndersogelseGeological Map of GreenlandGreenland Geological Survey, 1: 2, 500, 000GreenlandGeological map of Greenland, Map -ad
DS1998-1356
1998
Gronvold, K.Slater, L., Jull, M., Gronvold, K.Deglaciation effects on mantle melting under Iceland: results from the northern volcanic zone.Earth and Planetary Science Letters, Vol.164, No.1-2, Dec.15, pp.151-78.GlobalGeomorphology, Mantle hot spots
DS2000-0894
2000
Gronvold, K.Sigurdson, I.A., Steinthorsson, S., Gronvold, K.Calcium rich melt inclusions in chromium spinels from Borgarhraun, northern Iceland.Earth and Planetary Science Letters, Vol.183, No.1-2, Nov.30, pp.15-26.GlobalMineral chemistry - chromium spinels
DS2001-0715
2001
Gronvold, K.Maclennan, J., McKenzie, D., Gronvold, K., Slater, L.Crustal accretion under northern IcelandEarth and Planetary Science Letters, Vol. 191, No. 3-4, pp. 295-310.GlobalTectonics, geodynamics
DS2001-0716
2001
Gronvold, K.Maclennan, J., McKenzie, D.M., Gronvold, K.Plume driven upwelling under central IcelandEarth and Planetary Science Letters, Vol. 194, No. 1-2, pp. 67-82.IcelandHot spots, Herdubreid region, Northern Volcanic Zone
DS200512-0672
2005
Gronvold, K.MacPherson, C.G., Hilton, D.R., Day, J.M.D., Lowry, D., Gronvold, K.High He3 He4 depleted mantle and low delta18O recycled oceanic lithosphere in the source of central Iceland magmatism.Earth and Planetary Science Letters, Vol. 233, 3-4, May 15, pp. 411-427.Europe, IcelandMagmatism, geochronology, recycling
DS1986-0267
1986
Grooms, D.G.Garcia, M.O., Frey, F.A., Grooms, D.G.Petrology of volcanic rocks from Kaula Island Hawaii. Implications for The origin of Hawaiian phonolitesContributions to Mineralogy and Petrology, Vol. 94, No. 4, pp. 461-471HawaiiBasanite, rare earth elements (REE).
DS201806-1235
2018
Groppelli, G.Marti, J., Groppelli, G., Brum da Silveira, A.Volcanic stratigraphy: a review.Journal of Volcanology and Geothermal Research, Vol. 357, pp. 68-91.Mantlevolcanism

Abstract: Volcanic stratigraphy is a fundamental component of geological mapping in volcanic areas as it yields the basic criteria and essential data for identifying the spatial and temporal relationships between volcanic products and intra/inter-eruptive processes (earth-surface, tectonic and climatic), which in turn provides greater understanding of the geological evolution of a region. Establishing precise stratigraphic relationships in volcanic successions is not only essential for understanding the past behaviour of volcanoes and for predicting how they might behave in the future, but is also critical for establishing guidelines for exploring economic and energy resources associated with volcanic systems or for reconstructing the evolution of sedimentary basins in which volcanism has played a significant role. Like classical stratigraphy, volcanic stratigraphy should also be defined using a systematic methodology that can provide an organised and comprehensive description of the temporal and spatial evolution of volcanic terrain. This review explores different methods employed in studies of volcanic stratigraphy, examines four case studies that use differing stratigraphic approaches, and recommends methods for using systematic volcanic stratigraphy based on the application of the concepts of traditional stratigraphy but adapted to the needs of volcanological environment.
DS200612-0503
2006
Groppo, C.Groppo, C., Rinaudo, C.,Cairo, S., Gastaldi, D., Compagnoni, R.Micro-raman spectroscopy for a quick and reliable identification of serpentine minerals from ultramafics.European Journal of Mineralogy, Vol. 18, 3, May pp. 319-329.TechnologySpectroscopy - not specific to diamonds
DS201412-0521
2014
Groppo, C.Liu, Y-C., Deng, L-P., Gu, X-F., Groppo, C., Rolfo, F.Application of Ti in zircon and Zr in rutile thermometers to constrain high temperature metamorphism in eclogites from the Dabie Orogen, central China.Gondwana Research, Vol. 27, pp. 410-423.ChinaEclogite
DS202009-1623
2019
Groppo, C.Deng, L-P., Liu, Y-C., Yang, Y., Groppo, C., Rolfo, F., Gu, X-F.Anatexis of high-T eclogites in the Dabie orogen triggered by exhumation and post-orogenic collapse.European Journal of Mineralogy, Vol. 31, pp. 889-803. pdfChinaeclogite

Abstract: A combined study of detailed petrographic observation, mineral chemistry analysis and phase equilibrium modeling indicates that the high-temperature eclogites from the Dabie orogen, central China, experienced two episodes of anatexis: the first is phengite dehydration melting during the exhumation of deeply subducted slices, and the second is heating melting related to the post-orogenic collapse. Petrographic evidence and clues of the anatectic events include biotite + plagioclase + garnet ± amphibole intergrowth in matrix and biotite + plagioclase intergrowth within amphibole porphyroblast. Pressure-temperature (P-T) pseudosection and modal variation diagram indicate that the biotite + plagioclase + garnet ± amphibole in matrix was formed by the reactions phengite + clinopyroxene + quartz = melt + sanidine + garnet + plagioclase and later melt + sanidine + garnet = biotite + plagioclase, while the biotite + plagioclase intergrowths within poikiloblastic amphibole were formed by the reaction amphibole + muscovite + epidote = biotite + plagioclase + melt. In addition, the combination of petrological observations and P-T estimates suggests that the first melting event occurred at the late Triassic, while the second is related to the early Cretaceous mountain-root removal and subsequent asthenospheric upwelling and heat input. As the P-T paths of high-temperature/ultrahigh-pressure rocks have high probabilities to cross-cut phengite-melting curves, phengite melting during decompression may be a common process in these rocks. Moreover, the coexistence of multiple episodes of anatexis in a single tectonic slice suggests caution when identifying and dating partial melting in high-temperature/(ultra)high-pressure rocks.
DS1996-1078
1996
Gros, M.Pattow, L., Lorand, J.P., Gros, M.Earth's mantleNature, Vol. 379, No. 6567, Feb. 22, p. 712-MantleGeodynamics
DS201112-0390
2011
Grosch, E.G.Grosch, E.G., Kosler, J., McLoughlin, N., Drost, K., Slama, J., Pedersen, R.B.Paleoarchean detrital zircon ages from the earliest tectonic basin in the Barberton greenstone belt, Kaapvaal craton, South Africa.Precambrian Research, Vol. 191, 1-2, pp. 85-99.Africa, South AfricaGeochronology
DS1995-1175
1995
Grosch, U.Massone, H.J., Grosch, U.P-T evolution of Paleozoic garnet peridotites from the Saxonian Erzebirgeand the Aheim region, W. Norway.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 353-355.NorwayPeridotites, Erzebirge and Aheim regions
DS200612-1427
2006
Grosche, G.Tichomirowa, M., Grosche, G., Gotze, J., Belyatsky, B.V., Savva, E.V., Keller, J., Todt, W.The mineral isotope composition of two Precambrian carbonatite complexes from the Kola Alkaline Province - alteration versus primary magmatic signatures.Lithos, In press available,Russia, Kola PeninsulaCarbonatite, geochronology, Tiksheozero, Siilinkarvi
DS1991-1456
1991
Groschel-Becker, H.Rosendahl, B.R., Groschel-Becker, H., Meyers, J., Kaczmarick, K.Deep seismic reflection study of a passive margin southeastern Gulf ofGuineaGeology, Vol. 19, No. 4, April pp. 291-295GuineaGeophysics -seismics, Remote sensing
DS201711-2533
2017
Groschopf, N.Veter, M., Foley, S.F., Mertz-Kraus, R., Groschopf, N.Trace elements in olivine of ultramafic lamprophyres controlled by phlogopite rich mineral assemblages in the mantle source.Lithos, Vol. 292-293, pp. 81-95.Mantlelamprophyres

Abstract: Carbonate-rich ultramafic lamprophyres (aillikites) and associated rocks characteristically occur during the early stages of thinning and rifting of cratonic mantle lithosphere, prior to the eruption of melilitites, nephelinites and alkali basalts. It is accepted that they require volatile-rich melting conditions, and the presence of phlogopite and carbonate in the source, but the exact source rock assemblages are debated. Melts similar to carbonate-rich ultramafic lamprophyres (aillikites) have been produced by melting of peridotites in the presence of CO2 and H2O, whereas isotopes and trace elements appear to favor distinct phlogopite-bearing rocks. Olivine macrocrysts in aillikites are usually rounded and abraded, so that it is debated whether they are phenocrysts or mantle xenocrysts. We have analyzed minor and trace element composition in olivines from the type aillikites from Aillik Bay in Labrador, Canada. We characterize five groups of olivines: [1] mantle xenocrysts, [2] the main phenocryst population, and [3] reversely zoned crystals interpreted as phenocrysts from earlier, more fractionated, magma batches, [4] rims on the phenocrysts, which delineate aillikite melt fractionation trends, and [5] rims around the reversely zoned olivines. The main phenocryst population is characterized by mantle-like Ni (averaging 3400 ?g g? 1) and Ni/Mg at Mg# of 88-90, overlapping with phenocrysts in ocean island basalts and Mediterranean lamproites. However, they also have low 100 Mn/Fe of 0.9-1.3 and no correlation between Ni and other trace elements (Sc, Co, Li) that would indicate recycled oceanic or continental crust in their sources. The low Mn/Fe without high Ni/Mg, and the high V/Sc (2-5) are inherited from phlogopite in the source that originated by solidification of lamproitic melts at the base of the cratonic lithosphere in a previous stage of igneous activity. The olivine phenocryst compositions are interpreted to result from phlogopite and not high modal pyroxene in the source. The presence of kimberlites and ultramafic lamprophyres of Mesozoic age in Greenland indicates the persistence of a steep edge to the cratonic lithosphere at a time when this had been removed from the western flank in Labrador.
DS1860-0751
1892
Groser, A.Groser, A.South African Experiences in Cape Colony, Natal and PondolanLondon: Simpkin Marshall, Africa, South AfricaKimberley, Travelogue
DS1995-0507
1995
GrosfilsErnst, R.E., Head, J.W., Parfitt, Grosfils, WilsonGiant radiating dyke swarms on Earth and VenusEarth Science Reviews, Vol. 39, No. 1-2, Sept. pp. 1-58.GlobalDyke swarms, Review
DS1995-0510
1995
Grosfils, E.Ernst, R.E., Head, J.W., Parfitt, E., Grosfils, E., WilsonGiant radiating dyke swarms on Earth and VenusEarth Science Reviews, Vol. 39 No. 1-2, Sept. pp. 1-58GlobalDike swarms, Review
DS201212-0260
2012
Grosfils, E.B.Gregg, P.M., De Silva, S.L., Grosfils, E.B., Parmigiani, J.P.Catastrophic caldera forming eruptions: thermomechanics and implications for eruption triggering and maximum caldera dimensions on Earth.Journal of Volcanology and Geothermal Research, Vol. 242-242, pp. 1-12.MantleCalderas
DS201412-0752
2014
Grosfils, E.B.Rooney, T.O., Bastow, I.D., Keir, D., Mazzarini, F., Movsesian, E., Grosfils, E.B., Zimbelman, J.R., Ramsey, M.S., Ayalew, D., Yirgu, G.The protracted development of focused magmatic intrusion during continental rifting.Tectonics, Vol. 33, 6, pp. 875-897.Africa, EthiopiaPrecambrian lineaments
DS1992-0624
1992
Groskinsky, B.L.Groskinsky, B.L.The use of write-once, read, many optical discs for temporary and archivalstorageUnited States Geological Survey (USGS) Open File, No. 92-0036, 7p. $ 1.50GlobalComputer, Program
DS1960-0331
1963
Gross, B.Craddock, C.E., Thiel, C., Gross, B.A Gravity Investigation of the Precambrian of Southeastern Minnesota and Western Wisconsin.Journal of GEOPHYSICAL RESEARCH, Vol. 68, No. 21, PP. 6015-6032.GlobalGeophysics, Mid-continent
DS1950-0328
1957
Gross, F.Gross, F.Rhodes of AfricaNew York: Praeger Publishing, 433P.South Africa, Cape Province, Kimberley AreaBiography, Kimberley
DS201909-2047
2019
Gross, J.Howarth, G.H., Gross, J.Diffusion controlled and concentric growth zoning revealed by phosphorous in olivine from rapidly ascending kimberlite magma, Benfontein, South Africa.Geochimica et Cosmochimica Acta, in press available 49p. PdfAfrica, South Africadeposit - Benfontein

Abstract: Olivine chemistry has been widely used to track the petrogenesis of mafic and ultramafic magmas from their mantle source to eruption at the surface. A major challenge in these studies is deciphering crystal growth versus diffusion controlled zoning. Here we report a multi-element approach using high-precision electron microprobe techniques to evaluate crystal growth versus diffusion in kimberlitic olivine from the Benfontein kimberlite, South Africa. These results have implications for both the petrogenesis of kimberlite magmas and the understanding of crystal growth and diffusion-based zoning in igneous olivine in general. The Benfontein olivine contain multiple phosphorous (P)-rich and P-poor zones. Core zones are characterized by homogenous low-P (<78?ppm) concentrations, consistent with xenocrystic origins. Gradational changes in Fo, Ni, Cr and other minor/trace elements at core-margins are similarly characterized by constant low-P concentrations that are indistinguishable from the central regions of the core. Olivine P-maps effectively outline the original xenocryst core, whereas gradational margins are interpreted as diffusion controlled zones related to early-stage equilibration of xenocrystic olivine with proto-/kimberlite melt. Multiple P-poor (100-150?ppm) and P-rich (200-450?ppm) concentric, oscillatory zones with inclusions of kimberlitic oxide phases are observed surrounding the low-P xenocrystic cores. Oxide phases change from chromite in the inner zones to ilmenite in the intermediate zones to magnetite-rich spinel in the outer zones of the olivine. The P-zoning corresponds with changes in Fo content implying that stages of crystal growth was preserved by both fast and slow diffusing elements rather than diffusion processes. Elements compatible with olivine (±chromite) crystallization (i.e., Ni and Cr) display a constant decrease across all zones, suggesting that magma mixing is unlikely a controlling process for P-zoning. We interpret P-rich zones to result from stages of solute trapping related of rapid disequilibrium growth driven by extrinsic factors such as changes in pressure-temperature during kimberlite evolution. In contrast, P-poor zones represent stages of equilibrium crystal growth. The outer olivine zones are characterized by an increase in Fo contents up to Fo96, and in conjunction with a change to more Fe3+-rich oxides, suggest late stage increase in fO2. Correlated Fo and P changes in the Benfontein olivine suggest that major element zonation represents an example where crystal growth-induced Fo zoning has been preserved in olivine. Furthermore, P-rich olivine zones preserve evidence for concentric growth rather than common dendritic structures seen in other occurrences. These results have implications for understanding the effect of magma dynamics and changes in pressure-temperature-fO2 conditions on olivine growth in igneous rocks.
DS200712-0387
2007
Gross, J.P.Gross, J.P., Briddon, P.R., Shaw, M.J.Density functional simulations of silicon containing point defects in diamond.Physical Review Letters, Vol. 76, 7, pp. 075204. Ingenta 1074186736TechnologyDiamond morphology
DS1950-0473
1959
Gross, M.L.Gross, M.L.The Incredible American Diamond Mine MysteryTrue, The Man's Magazine., SEPT. PP. 52-55; PP. 98-102.United States, Gulf Coast, Arkansas, PennsylvaniaDiamond, Mining, History
DS1993-0412
1993
Gross, M.R.Engelder, T., Gross, M.R.Curving cross joints and the lithospheric stress field in eastern NorthAmericaGeology, Vol. 21, No. 9, September pp. 817-820Appalachia, New YorkTectonics
DS202003-0367
2020
Grosse, G.Turetsky, M.R., Abbott, B.W., Jones, M.C., Walter Anthony, K.. Olefeldt, D., Schuur, E.A.G., Grosse, G., Kuhry, P., Higelius, G., Koven, C., Lawrence, D.M., Gibson, C., Sannel, A.B.K., McGuire, A.D.Carbon release through abrupt permafrost thaw. ( not specific to diamonds but interest)Nature Geoscience, Vol. 13, pp. 138-143.Mantlecarbon

Abstract: The permafrost zone is expected to be a substantial carbon source to the atmosphere, yet large-scale models currently only simulate gradual changes in seasonally thawed soil. Abrupt thaw will probably occur in <20% of the permafrost zone but could affect half of permafrost carbon through collapsing ground, rapid erosion and landslides. Here, we synthesize the best available information and develop inventory models to simulate abrupt thaw impacts on permafrost carbon balance. Emissions across 2.5?million?km2 of abrupt thaw could provide a similar climate feedback as gradual thaw emissions from the entire 18?million?km2 permafrost region under the warming projection of Representative Concentration Pathway 8.5. While models forecast that gradual thaw may lead to net ecosystem carbon uptake under projections of Representative Concentration Pathway 4.5, abrupt thaw emissions are likely to offset this potential carbon sink. Active hillslope erosional features will occupy 3% of abrupt thaw terrain by 2300 but emit one-third of abrupt thaw carbon losses. Thaw lakes and wetlands are methane hot spots but their carbon release is partially offset by slowly regrowing vegetation. After considering abrupt thaw stabilization, lake drainage and soil carbon uptake by vegetation regrowth, we conclude that models considering only gradual permafrost thaw are substantially underestimating carbon emissions from thawing permafrost.
DS1991-0338
1991
Grossi Sad, J.H.Danni, J.C.M., Botelho, N.F., Grossi Sad, J.H.Bulk and mineral chemistry of the olivine leucitite from Juana Vaz, Sacramento, Minas Gerais, BrasilProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 60-62BrazilRock chemistry, Leucitite -analyses
DS1997-1087
1997
Grossman, J.N.Sorensen, S.S., Grossman, J.N.Phengite hosted large-ion lithophile elements (LILE) enrichment in eclogite and related rocks: Implications for fluid mediated mass transferJournal of Petrology, Vol. 38, No. 1, Jan. 1, pp. 3-34.MantleMagma genesis, Subduction
DS200512-1240
2005
Grossman, J.N.Zhang, C., Manheim, F.T., Hinde, J., Grossman, J.N.Statistical characteristics of a large geochemical database and effect of sample size.Applied Geochemistry, Vol.20, 10, Oct. pp. 1857-1874.TechnologyGeochemistry - not specific to diamonds
DS1989-0834
1989
Grossman, L.Kuehner, S.M., Laughlin, J.R., Grossman, L., Johnson, M.L., BurnettDetermination of trace element mineral/liquid partition coefficients in melilite and diopside by ion and electron microprobe techniquesGeochimica et Cosmochimica Acta, Vol. 53, pp. 3115-3130GlobalMelilite, Experimental petrology
DS200612-1308
2006
Grossman, L.Simon, S.B., Grossman, L.A comparative study of melilite and fassaite in types B1 and B2 refractory inclusions.Geochimica et Cosmochimica Acta, Vol. 70, 3, Feb. 1, pp. 780-798.TechnologyPetrology
DS2002-1075
2002
Groten, E.Molodensky, S.M., Groten, E.On the models of the lower mantle viscosity consistent with the modern dat a of core - mantle boundary flattening.Studia Geophisca et Geodaetica, Ingenta 1023463147, Vol. 46, 3,pp.411-33.MantleGeophysics - seismics
DS1860-0551
1887
Groth, P.H.Groth, P.H.Grundriss der EdelsteinkundeLeipzig:, 165P.GlobalGemology
DS1990-0607
1990
Grotzinger, J.Grotzinger, J., Royden, L.Elastic strength of the Slave craton at 1.9 Gyr and implications for the thermal evolution of the continentsNature, Vol. 347, No. 6288, September 6, pp. 64-66Northwest TerritoriesCraton, Georchronology, Age determination
DS2002-1596
2002
Grotzinger, J.Tinker, J., De Wit, M.J., Grotzinger, J.Seismic stratigraphic constraints on Neoarchean Paleoproterozoic evolution of the western margin of the Kaapvaal Craton, South Africa.Geological Society of South Africa, Vol. 105, No. 2, pp. 107-34.South AfricaGeophysics - seismics, craton - margin
DS1991-1325
1991
Grotzinger, J.P.Pelechaty, S.M., James, N.P., Kerans, C., Grotzinger, J.P.A middle Proterozoic paleokarst unconformity and associated sedimentaryrocks, Elu basin, Northwest CanadaSedimentology, Vol. 38, No. 5, October pp. 775-798Northwest TerritoriesBasin, Proterozoic
DS1992-0154
1992
Grotzinger, J.P.Bowring, S.A., Grotzinger, J.P.Implications of new chronostratigraphy for tectonic evolution of Wopmayorogen, northwest Canadian ShieldAmerican Journal of Science, Vol. 292, January pp. 1-20Northwest TerritoriesGeochronology, Wopmay Orogen
DS1993-0586
1993
Grotzinger, J.P.Grotzinger, J.P., Kasting, J.F.New constraints on Precambrian Ocean compositionJournal of Geology, Vol. 101, pp. 235-43.OceanPrecambrian, Geochemistry
DS1993-0682
1993
Grotzinger, J.P.Hoffman, P.F., Grotzinger, J.P.Orographic precipitation, erosional unloading and tectonic styleGeology, Vol. 21, No. 3, March pp. 195-198Northwest Territories, Cordillera, Appalachia, OntarioTectonics, Orogeny, Slave Craton
DS1996-0459
1996
Grotzinger, J.P.Flemings, P.B., Grotzinger, J.P.STRATA: freeware for analyzing classic stratigraphic problemsGsa Today, Vol. 6, No. 12, Dec. pp. 1-8GlobalComputer program -STRATA., Stratigraphy
DS1996-1097
1996
Grotzinger, J.P.Pelevhaty, S.M., Grotzinger, J.P., Kashirtsev, V.A., et al.Chemostratigraphic and sequence stratigraphic constraints on Vendian Cambrian basin dynamics.Journal of Geology, Vol. 104, No. 5, Sept. pp. 543-563.Russia, SiberiaBasin development, Craton -Siberia
DS201512-1971
2015
Groulier, P.ASolgadi, F., Groulier, P.A, Moukhsil, A., Ohnenstetter, D., Andre-Mayer, A.S., Zeh, A.Nb-Ta-REE mineralization associated with the Crevier alkaline intrusion.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 69-74.Canada, QuebecAlkalic

Abstract: The Crevier alkaline intrusion is in the Grenville Province, north of the Lac Saint-Jean region of Québec (Fig. 1). It covers ~25 km2 (Bergeron, 1980) and intrudes charnockitic suites in the allochthon belt defi ned by Rivers et al. (1989). This intrusion has a U-Pb zircon age of 957.5 ± 2.9 Ma (Groulier et al., 2014) and is oriented N320°, along the axis of crustal weakness known as the Waswanipi-Saguenay corridor (Bernier and Moorhead, 2000). This corridor is related to the Saguenay graben, which hosts the Saint-Honoré (Niobec) Nb-Ta-REE deposit and Montviel REE deposit. The age of the Saint-Honoré carbonatite was estimated at 584 to 650 Ma (K-Ar whole rock; Vallée and Dubuc, 1970; Boily and Gosselin, 2004). The Montviel intrusion has a U-Pb zircon age of 1894 ± 3.5 Ma (David et al., 2006; Goutier, 2006). These crystallization ages are very different and cannot be related to a single event for the injection of alkaline intrusions. As mapped by Bergeron (1980), the Crevier alkaline intrusion is broadly composed of syenite and carbonatite rocks (Fig. 2). The Nb- Ta mineralization consists of pyrochlore hosted by a nepheline syenite dike swarm in the centre of the intrusion. The highest REE concentrations, up to 729 ppm La and 1465 ppm Ce, are at the edge of the Crevier alkaline intrusion (Niotaz sud showing; Fig. 2).
DS201412-0321
2014
Groulier, P.A.Groulier, P.A., Andre-Mayer, A.S., Ohnenstetter, D., Zeh, A., Moukhsil, A., Solgadi, F., El Basbas, A.Petrology, geochemistry and age of the Crevier alkaline intrusion.GAC-MAC Annual Meeting May, abstract 1p.Canada, QuebecAlkalic
DS200912-0144
2009
Grousset, F.E.Dale, C.W., Pearson, D.G., Starkey, N.A., Stuart, F.M., Ellam, R.M., Larsen, L.M., Fitton, J.G., Grousset, F.E.Osmium isotopes in Baffin Island and West Greenland picrites: implications for the 187 Os and 188 Os composition of the convection mantle and nature 3He/4heEarth and Planetary Interiors, Vol. 278, 3-4, pp. 267-277.MantleConvection
DS2001-0890
2001
GroveParman, S.W., Grove, Dann, J.C.The production of Barberton komatiites in an Archean subduction zoneGeophysical Research Letters, Vol. 28, No. 13, July 1, pp. 2513-16.South AfricaSubduction, Mantle plumes
DS2000-1031
2000
Grove, M.Xu, B., Grove, M., Liu, S.40 Ar-39 Ar thermochronology from the northwestern Dabie Shan: constraints on evolution of Qinling-DabieTectonophysics, Vol. 322, No. 3-4, July 30, pp. 279-301.China, East CentralTectonics, geothermal, geochronology, Argon, Dabie Shan orogenic belt
DS2002-0628
2002
Grove, M.Hacker, B.R., Grove, M.Was UHP tectonism in Norway caused by ophiolite emplacement?Geological Society of America Annual Meeting Oct. 27-30, Abstract p. 511.NorwayUHP - not specific to diamonds
DS200612-0518
2006
Grove, M.Hacker, B.R., Wallis, S.R., Ratschbacher, L., Grove, M., Gehrels, G.High temperature geochronology constraints on the tectonic history and architecture of the ultrahigh pressure Dabie-Sulu Orogen.Tectonics, Vol. 25, 5, TC5006ChinaUHP, tectonics
DS1993-0476
1993
Grove, T.L.Gaetani, G.A., Grove, T.L., Bryan, W.B.The influence of water on the petrogenesis of subduction related igneousrocksNature, Vol. 365, No. 6444, September 23, pp. 332-335GlobalSubduction, Igneous rocks, Mantle
DS1994-0561
1994
Grove, T.L.Gaetani, G.A., Grove, T.L.Melting in the sub arc mantle: effects of H2O on primary magmas and the spinel to garnet transition.Mineralogical Magazine, Vol. 58A, pp. 301-302. AbstractMantleMagma transitions, Peridotite
DS1996-0232
1996
Grove, T.L.Carlson, R.W., Grove, T.L., De Wit, M.J., Gurney, J.J.Program to study crust and mantle of the Archean craton in southernAfrica.Eos, Vol. 77, No. 29, July 16, pp. 273, 277.South AfricaKaapvaal Craton, Chemistry, geochemistry, geochronology, geodynamics
DS1998-0459
1998
Grove, T.L.Gaetani, G.A., Grove, T.L.The influence of water on melting of mantle peridotiteContributions to Mineralogy and Petrology, Vol. 131, No. 4, May pp. 323-46.MantleMelting, Peridotite
DS1998-0751
1998
Grove, T.L.Kinzler, R.J., Grove, T.L.Origin of depleted cratonic harzburgite by deep fract. melt extraction and shallow olivine cumulate infusion.7th International Kimberlite Conference Abstract, pp. 426-428.GlobalCraton - mantle melt, Harzburgite
DS1998-0774
1998
Grove, T.L.Koga, K.T., Shimizu, N., Grove, T.L.Disequilibrium trace element re-distribution during garnet to spinel faciestransformation.7th International Kimberlite Conference Abstract, pp. 443-5.GlobalGeochemistry - trace element, chondrite, Petrology - experimental
DS1999-0232
1999
Grove, T.L.Gaetani, G.A., Grove, T.L.Wetting of mantle olivine by sulfide melt: implications for Re/Os ratios In mantle peridotite and late stage ..Earth and Planetary Science Letters, Vol. 169, No. 1-2, May 30, pp. 147-64.MantleSulphides, peridotite, Georchronology - late stage core formation
DS2001-0815
2001
Grove, T.L.Muntener, O., Kelemen, P.B., Grove, T.L.The role of H2O during crystallization of primitive arc magmas under uppermost mantle conditions and genesis..Contributions to Mineralogy and Petrology, Vol. 141, pp. 643-58.GlobalPyroxenites - igneous, Petrology - experimental
DS2001-0816
2001
Grove, T.L.Muntener, O., Kelemen, P.B., Grove, T.L.The role of H20 during crystallization of primitive arc magmas under uppermost mantle conditions and genesis...Contributions to Mineralogy and Petrology, Vol. 141, No. 6, pp. 643-58.MantlePyroxenites - igneous, Petrology - experimental
DS2001-1004
2001
Grove, T.L.Saltzer, R.L., Chatterjee, N., Grove, T.L.The spatial distribution of garnets and pyroxenes in mantle peridotites pressure temperature history...Journal of Petrology, Vol. 42, No. 12, pp. 2215-30.South AfricaCraton - Kaapvaal, Peridotites
DS2001-1149
2001
Grove, T.L.Tanton, L.T.E., Grove, T.L., Donnelly-Nolan, J.Hot shallow mantle melting under the Cascades volcanic arcGeology, Vol. 19, No. 7, July pp. 631-4.California, OregonSubduction - not related to diamonds
DS2001-1187
2001
Grove, T.L.Van Orman, J.A., Grove, T.L., Shimizu, N.Rare earth element diffusion in diopside: influence of temperature, pressure and ionic radius and model...Contributions to Mineralogy and Petrology, Vol. 141, pp. 687-703.mantleModel - elastic model for diffusion in silicates
DS2002-1648
2002
Grove, T.L.Van Orman, J.A., Grove, T.L., Shimizu, N.Diffusive fractionation of trace elements during production and transport of melt Earth's upper mantleEarth and Planetary Science Letters, Vol.198,1-2,pp.93-112., Vol.198,1-2,pp.93-112.MantleMineralogy - trace elements
DS2002-1649
2002
Grove, T.L.Van Orman, J.A., Grove, T.L., Shimizu, N.Diffusive fractionation of trace elements during production and transport of melt Earth's upper mantleEarth and Planetary Science Letters, Vol.198,1-2,pp.93-112., Vol.198,1-2,pp.93-112.MantleMineralogy - trace elements
DS2002-1650
2002
Grove, T.L.Van Orman, J.A., Grove, T.L., Shimizu, N., Layne, G.D.Rare earth element diffusion in a natural pyrope single crystal at 2.8 GPaContributions to Mineralogy and Petrology, Vol. 142, No. 4, pp. 416-25.GlobalPetrology - garnet not specific to diamond
DS2003-0094
2003
Grove, T.L.Bell, D.R., Gregoire, M., Grove, T.L., Chatterjee, N.D., Bowring, S.A.Silica and carbon deposition in Kimberley peridotites8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, AbstractSouth AfricaMantle petrology, Deposit - Bultfontein
DS2003-0380
2003
Grove, T.L.Elkins-Tanton, L.T., Grove, T.L.Evidence for deep melting of hydrous metasomatized mantle: Pliocene high potassiumJournal of Geophysical Research, Vol. 108, B8, Aug. 2, 10.1029/2002jb002168.CaliforniaGeophysics - seismics, Metasomatism
DS2003-0434
2003
Grove, T.L.Gaetani, G.A., Kent, A.J., Grove, T.L., Hutcheon, I.D., Stolper, E.M.Mineral melt partitioning of trace elements during hydrous peridotite partial meltingContributions to Mineralogy and Petrology, Vol. 145, 4, pp. 391-405.MantlePeridotites
DS2003-0507
2003
Grove, T.L.Grove, T.L., Elkins-Tanton, L.T., Hesse, M.Melting processes in continental lithosphere: effects of mantle metasomatism on meltGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.395.California, MexicoMetasomatism - not specific to diamonds
DS2003-0508
2003
Grove, T.L.Grove, T.L., Elkins-Tanton, L.T., Parman, S.W., Chatterjee, N., Muntener, O.Fractional crystallization and mantle melting controls on calc-alkaline differentiationContributions to Mineralogy and Petrology, Vol. 145, 5, pp. 515-533.MantleGeochemistry - alkaline
DS2003-0579
2003
Grove, T.L.Hesse, M., Grove, T.L.Absarokites from the western Mexican Volcanic Belt: constraints on mantle wedgeContributions to Mineralogy and Petrology, Vol. 146, 1, Oct. pp. 10-27.MexicoMantle wedge - Jalico Block, metasomatism - not specifi
DS200412-0127
2003
Grove, T.L.Bell, D.R., Gregoire, M., Grove, T.L., Chatterjee, N.D., Bowring, S.A.Silica and carbon deposition in Kimberley peridotites.8 IKC Program, Session 6, AbstractAfrica, South AfricaMantle petrology Deposit - Bultfontein
DS200412-0517
2003
Grove, T.L.Elkins-Tanton, L.T., Grove, T.L.Evidence for deep melting of hydrous metasomatized mantle: Pliocene high potassium magmas from the Sierra Nevadas.Journal of Geophysical Research, Vol. 108, B8, Aug. 2, 10.1029/2002 jb002168.United States, CaliforniaGeophysics - seismics Metasomatism
DS200412-0598
2003
Grove, T.L.Gaetani, G.A., Kent, A.J., Grove, T.L., Hutcheon, I.D., Stolper, E.M.Mineral melt partitioning of trace elements during hydrous peridotite partial melting.Contributions to Mineralogy and Petrology, Vol. 145, 4, pp. 391-405.MantlePeridotite
DS200412-0730
2003
Grove, T.L.Grove, T.L., Elkins-Tanton, L.T., Hesse, M.Melting processes in continental lithosphere: effects of mantle metasomatism on melt composition.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p.395.United States, CaliforniaMetasomatism - not specific to diamonds
DS200412-0731
2003
Grove, T.L.Grove, T.L., Elkins-Tanton, L.T., Parman, S.W., Chatterjee, N., Muntener, O., Gaetani, G.A.Fractional crystallization and mantle melting controls on calc-alkaline differentiation trends.Contributions to Mineralogy and Petrology, Vol. 145, 5, pp. 515-533.MantleGeochemistry - alkaline
DS200412-0732
2004
Grove, T.L.Grove, T.L., Parman, S.W.Thermal evolution of the Earth as recorded by komatiites.Earth and Planetary Science Letters, Vol. 219, 3-4, March 15, pp. 173-187.MantlePlume, boninites, subduction zones, melting
DS200412-0820
2003
Grove, T.L.Hesse, M., Grove, T.L.Absarokites from the western Mexican Volcanic Belt: constraints on mantle wedge conditions.Contributions to Mineralogy and Petrology, Vol. 146, 1, Oct. pp. 10-27.MexicoMantle wedge - Jalico Block, metasomatism - not specifi
DS200412-1504
2004
Grove, T.L.Parman, S.W., Grove, T.L., Dann, J.C., De Wit, M.J.A subduction origin for komatiites and craton lithospheric mantle.South African Journal of Geology, Vol. 107, 1/2, pp. 107-118.Africa, South AfricaSubduction
DS200512-0088
2005
Grove, T.L.Bindeman, I.N., Eiler, J.M., Yogodzinski, Y., Stern, C.R., Grove, T.L., Portnyagin, Hoernle, DanyushevskyOxygen isotope evidence for slab melting in modern and ancient subduction zones.Earth and Planetary Science Letters, Vol. 235, 3-4, July 15, pp. 480-496.MantleSubduction
DS200512-0821
2005
Grove, T.L.Parman, S.W., Grove, T.L.Komatiites in the plume debate.Plates, Plumes, and Paradigms, pp. 249-256. ( total book 861p. $ 144.00)MantleKomatiite
DS200612-0115
2005
Grove, T.L.Bell, D.R., Gregoire, M., Grove, T.L., Chaterjee, N., Carlson, R.W., Buseck, P.R.Silica and volatile element metasomatism of Archean mantle: a xenolith scale example from the Kaapvaal Craton.Contributions to Mineralogy and Petrology, Vol. 150, 3, pp. 251-267.Africa, South AfricaMetasomatism
DS200612-0504
2006
Grove, T.L.Grove, T.L., Chatterjee, N., Parman, S.W., Medard, E.The influence of H2O on mantle wedge melting.Earth and Planetary Science Letters, Vol. 249, 1-2, Sept. 15, pp. 74-89.MantleWater, melting
DS200612-0505
2006
Grove, T.L.Grove, T.L., Chatterjee, N., Parman, S.W., Medard, E.The influence of H2O on mantle wedge melting.Earth and Planetary Science Letters, Vol. 249, 1-2, pp. 74-89.MantleWater, melting
DS200612-0679
2006
Grove, T.L.Kelley, K.A., Plank, T., Grove, T.L., Stolper,E.M., Newman, S., Hauri, E.Mantle melting as a function of water content beneath back arc basins.Journal of Geophysical Research, Vol. 111, B9, B09208.MantleSubduction zone magmatism
DS200712-0388
2007
Grove, T.L.Grove, T.L., Till, C.B.Processes controlling the relationship between volcanic fronts and the subducting slab revisited.Plates, Plumes, and Paradigms, 1p. abstract p. A358.MantleSubduction
DS200712-0523
2006
Grove, T.L.Kelley, K.A., Plank, T., Grove, T.L., Stolper, E.M., Newman, S., Hauri, E.Mantle melting as a function of water content beneath back arc basins.Journal of Geophysical Research, Vol. 111, B9, B09208.MantleMelting
DS200712-0524
2006
Grove, T.L.Kelley, K.A., Plank, T., Grove, T.L., Stolper, E.M., Newman, S., Hauri, E.Mantle melting as a function of water content beneath back arc basins.Journal of Geophysical Research, Vol. 111, B9, B09208.MantleWater
DS200812-0482
2008
Grove, T.L.Holbig, E.S., Grove, T.L.Mantle melting beneath the Tibetan Plateau: experimental constraints on ultrapotassic magmatism.Journal of Geophysical Research, Vol. 113, B4, B04210Asia, TibetMelting
DS201112-1046
2011
Grove, T.L.Till, C.B., Grove, T.L., Withers, A.C.The beginnings of hydrous mantle wedge melting.Contributions to Mineralogy and Petrology, in press available 20p.MantleSubduction - Cascades
DS201212-0264
2012
Grove, T.L.Grove, T.L., Till, C.B., Krawczynski, M.J.The role of H2O in subduction zone magmatism.Annual Review of Earth and Planetary Sciences, Vol. 40, pp. 413-439.MantleSubduction
DS201212-0730
2012
Grove, T.L.Till, C.B., Grove, T.L., Withers, A.C.The beginnings of hydrous mantle wedge melting.Contributions to Mineralogy and Petrology, Vol. 163, 4,MantleMelting
DS201312-0339
2013
Grove, T.L.Grove, T.L., Holbig, E.S., Barr, J.A., Till, C.B., Krawczynski, M.J.Inclusions in halite - evidence of mixing of evaporite xenoliths and kimberlites of Udachnaya -East pipe (Siberia).Contributions to Mineralogy and Petrology, Vol. 166, pp. 887-910.MantleMelting
DS201312-0340
2013
Grove, T.L.Grove, T.L., Till, C.B., Krawcznski, M.J.The role of H2O in subduction zone magmatism.Annual Review of Earth and Planetary Sciences, Vol. 40, pp. 413-439.MantleMagmatism, water
DS201312-0342
2013
Grove, T.L.Grove, T.L., Holbig, E.S., Barr, J.A., Till, C.B., Krawczynski, M.J.Melts of garnet lherzolite: experiments, models and comparison to melts of pyroxenite and carbonated lherzolite.Contributions to Mineralogy and Petrology, Vol. 166, pp. 887-910.South America, BrazilGeochronology (~91to 78)
DS201701-0022
2016
Grove, T.L.Mitchell, A.L., Grove, T.L.Experiments on melt-rock reaction in the shallow mantle wedge.Contributions to Mineralogy and Petrology, Vol. 171, pp. 107-MantleSubduction

Abstract: This experimental study simulates the interaction of hotter, deeper hydrous mantle melts with shallower, cooler depleted mantle, a process that is expected to occur in the upper part of the mantle wedge. Hydrous reaction experiments (~6 wt% H2O in the melt) were conducted on three different ratios of a 1.6 GPa mantle melt and an overlying 1.2 GPa harzburgite from 1060 to 1260 °C. Reaction coefficients were calculated for each experiment to determine the effect of temperature and starting bulk composition on final melt compositions and crystallizing assemblages. The experiments used to construct the melt-wall rock model closely approached equilibrium and experienced <5% Fe loss or gain. Experiments that experienced higher extents of Fe loss were used to critically evaluate the practice of “correcting” for Fe loss by adding iron. At low ratios of melt/mantle (20:80 and 5:95), the crystallizing assemblages are dunites, harzburgites, and lherzolites (as a function of temperature). When the ratio of deeper melt to overlying mantle is 70:30, the crystallizing assemblage is a wehrlite. This shows that wehrlites, which are observed in ophiolites and mantle xenoliths, can be formed by large amounts of deeper melt fluxing though the mantle wedge during ascent. In all cases, orthopyroxene dissolves in the melt, and olivine crystallizes along with pyroxenes and spinel. The amount of reaction between deeper melts and overlying mantle, simulated here by the three starting compositions, imposes a strong influence on final melt compositions, particularly in terms of depletion. At the lowest melt/mantle ratios, the resulting melt is an extremely depleted Al-poor, high-Si andesite. As the fraction of melt to mantle increases, final melts resemble primitive basaltic andesites found in arcs globally. An important element ratio in mantle lherzolite composition, the Ca/Al ratio, can be significantly elevated through shallow mantle melt-wall rock reaction. Wall rock temperature is a key variable; over a span of <80 °C, reaction with deeper melt creates the entire range of mantle lithologies from a depleted dunite to a harzburgite to a refertilized lherzolite. Together, the experimental phase equilibria, melt compositions, and reaction coefficients provide a framework for understanding how melt-wall rock reaction occurs in the natural system during melt ascent in the mantle wedge.
DS201911-2529
2019
Grove, T.L.Grove, T.L., Till, C.B.H2O rich mantle melting near the slab-wedge interface.Contributions to Mineralogy and Petrology, Vol. 174, 22p. PdfMantlesubduction, melting

Abstract: To investigate the first melts of the mantle wedge in subduction zones and their relationship to primitive magmas erupted at arcs, the compositions of low degree melts of hydrous garnet lherzolite have been experimentally determined at 3.2 GPa over the temperature range of 925-1150 °C. Two starting compositions with variable H2O contents were studied; a subduction-enriched peridotite containing 0.61% Na2O, 0.16 K2O% (wt%) with 4.2 wt% H2O added (Mitchell and Grove in Contrib Mineral Petrol 170:13, 2015) and an undepleted mantle peridotite (Hart and Zindler in Chem Geol 57:247-267, 1986) with 14.5% H2O added (Till et al. in Contrib Mineral Petrol 163:669-688, 2012). Saturating phases include olivine, orthopyroxene, clinopyroxene, garnet and rutile. Melting extent is tracked from near solidus (~?5 wt%) to 25 wt%, which is close to or beyond the point where clinopyroxene and garnet are exhausted. The beginning of melting is a peritectic reaction where 0.54 orthopyroxene?+?0.17 clinopyroxene?+?0.13 garnet react to produce 1.0 liquid?+?0.88 olivine. The melt production rate near the solidus is 0.1 wt% °C?1 and increases to 0.3 wt% °C?1 over the experimentally studied interval. These values are significantly lower than that observed for anhydrous lherzolite (~?1 wt% °C?1). When melting through this reaction is calculated for a metasomatized lherzolite source, the rare earth element characteristics of the melt are similar to melts of an eclogite, as well as those observed in many subduction zone magmas. Moreover, since rutile is stable up to?~?8 wt% melting, the first melts of a hydrous lherzolite source could also show strong high field strength element depletions as is observed in many subduction zone lavas. The silicate melts measured at the lowest temperatures and melting extents (
DS2000-0646
2000
GroverMcDonough, M.R., McNicoll, V.J., Schetselaar, GroverGeochronological and kinematic constraints on crustal shortening and escape in a two sided oblique slip...Canadian Journal of Earth Sciences, Vol.37, no11, Nov.pp.1549-73.Alberta, northeasternTectonics - Paleoproterozoic Taltson magmatic zone, Geochronology
DS1999-0270
1999
Grover, J.C.Grover, J.C.Earth Universe Cosmos: an inquest into our creeds (book by S.Warren Carey)Journal of Proceedings of the Royal Society. New South Wales., Vol. 132, pp. 118-22.GlobalBook review, Uniformitarianism, plate tectonics, BIF.
DS1992-0625
1992
Grover, T.P.Grover, T.P.Dat a acquisition system for magnetotelluricsUnited States Geological Survey (USGS) Open File, No. 92-0569, 29p. $ 4.50United StatesComputer, Program -magnetotellurics
DS1993-0587
1993
Grover, T.P.Grover, T.P., Kipfinger, R.P., Wright, D.L.A dual drawworks controller for borehole tomographyUnited States Geological Survey (USGS) Open File, No. 93-0324, 37p. $ 5.75GlobalComputer Program
DS202108-1315
2021
Grovers, R.Wouters, M.C., Perez-Diaz, L., Tuck-Martin, A., Eagles, G., Adam, J., Grovers, R.Dynamics of the African plate 75Ma: from plate kinematic reconstructions to interplate paleo-stresses,Tectonics, e2020TC006355Africageodynamics

Abstract: Plate reconstruction studies show that the Neotethys Ocean was closing due to the convergence of Africa and Eurasia toward the end of the Cretaceous. The period around 75 Ma reflects the onset of continental collision between the two plates as convergence continued to be taken up mostly by subduction of the Neotethys slab beneath Eurasia. The Owen transform plate boundary in the northeast accommodated the fast northward motion of the Indian plate relative to the African plate. The rest of the plate was surrounded by mid-ocean ridges. Africa was experiencing continent-wide rifting related to northeast-southwest extension. We aim to quantify the forces and paleostresses that may have driven this continental extension. We use the latest plate kinematic reconstructions in a grid search to estimate horizontal gravitational stresses (HGSs), plate boundary forces, and the plate's interaction with the asthenosphere. The contribution of dynamic topography to HGSs is based on recent mantle convection studies. We model intraplate stresses and compare them with the strain observations. The fit to observations favors models where dynamic topography amplitudes are smaller than 300 m. The results also indicate that the net pull transmitted from slab to the surface African plate was low. To put this into context, we notice that available tectonic reconstructions show fragmented subduction zones and various colliding micro-continents along the northern margin of the African plate around this time. We therefore interpret a low net pull as resulting from either a small average slab length or from the micro-continents' resistance to subduction.
DS201708-1578
2017
Groves, C.P.McIntyre, S.R.N., Lineweaver, C.H., Groves, C.P., Chopra, A.Global biogeography since Pangea.Proceedings of the Royal Society B: Biological sciences, Vol. 284. no 1856, pp.Mantlepangea

Abstract: The break-up of the supercontinent Pangaea around 180 Ma has left its imprint on the global distribution of species and resulted in vicariance-driven speciation. Here, we test the idea that the molecular clock dates, for the divergences of species whose geographical ranges were divided, should agree with the palaeomagnetic dates for the continental separations. Our analysis of recently available phylogenetic divergence dates of 42 pairs of vertebrate taxa, selected for their reduced ability to disperse, demonstrates that the divergence dates in phylogenetic trees of continent-bound terrestrial and freshwater vertebrates are consistent with the palaeomagnetic dates of continental separation.
DS1980-0144
1980
Groves, D.I.Glover, J.E., Groves, D.I.Kimberlites and Diamonds: a Seminar Organized by the Department Of Geology.Perth: West. Aust. University Geol. Department Extension Service., No. 5, 129P.AustraliaKimberlite, Kimberley, Janlib
DS1987-0094
1987
Groves, D.I.Cawthorn, R.G., Maske, S., de Wit, M., Groves, D.I., Cassidy, K.Mineralogical geochemical indicators of the formation conditions of apatite bearing carbonatites of the Arbarastakh Massif,Southern Yakutia (USSR).(Russian)Canadian Mineralogist, In pressSouth AfricaGenesis, Magma
DS1987-0260
1987
Groves, D.I.Groves, D.I., Ho, S.E., Rock, N.M.S., Barley, M.E., Muggeridge, M.T.Archean cratonsGeology, Vol. 15, No. 9, September pp. 801-805Canada, Wyoming, Southern Africa, Zimbabwe, Russia, AustraliaTectonics, Craton
DS1988-0579
1988
Groves, D.I.Rock, N.M.S., Groves, D.I.Do lamprophyres carry gold as well as diamonds?Nature, Vol. 332, No. 6161, March 17, pp. 253-256GlobalBlank
DS1989-0236
1989
Groves, D.I.Cawthorn, R.G., Bristow, J.W., Groves, D.I.Magnesian ilmenite in picritic basalts from the KarooprovinceSouthAfricaMineralogical Magazine, Vol. 53, No. 370, pp. 245-252South AfricaPicrite, Ilmenite
DS1991-0988
1991
Groves, D.I.Libby, J., Groves, D.I., Vearncombe, J.R.The nature and tectonic significance of the crustal scale Koolyanobbing shear zone, Yilgarn Craton, Western AustraliaAustralian Journal of Earth Sciences, Vol. 38, pp. 229-245AustraliaTectonics, Shear zone
DS1992-0086
1992
Groves, D.I.Barley, M.E., Groves, D.I.Supercontinent cycles and the distribution of metal deposits through timeGeology, Vol. 20, No. 4, April pp. 291-294GlobalMetallogeny, Pangea, Precambrian, Supercontinents, spatial
DS1992-1102
1992
Groves, D.I.Muller, D., Rock, N.M.S., Groves, D.I.Geochemical discrimination between shoshonitic and potassic volcanic Rocks in different tectonic settings: a pilot study.Mineralogy and Petrology, Vol. 46, No. 4, pp. 259-289.Andes, Alps, Mariana Trough, Sunda Arc, CordilleraGeochemistry, Shoshonites
DS1993-1094
1993
Groves, D.I.Muller, D., Groves, D.I.Direct and indirect associations between potassic igneous rocks, shoshonites and gold-copper depositsOre Geology Reviews, Vol. 8, No. 5, September pp. 383-406AustraliaIgneous rocks -potassic, alkaline, Deposits -gold, copper
DS1994-1253
1994
Groves, D.I.Muller, D., Heithersay, P.S., Groves, D.I.The shoshonite porphyry copper _ gold association in the Goonumbia district. New South WalesMineralogy and Petrology, Vol. 51, No. 2-4, pp. 299-322AustraliaCopper, gold, porphyry, Deposit -Goonumbia
DS1994-1664
1994
Groves, D.I.Solomon, M., Groves, D.I.The geology and origins of Australia's mineral depositsOxford University Press, 864pAustraliaMineral deposits, Book -ad
DS1994-1665
1994
Groves, D.I.Solomon, M., Groves, D.I., Jaques, A.The geology and origin of Australia's mineral depositsOxford Press, 960p. approx. $ 410.00AustraliaBook -table of contents, Deposits
DS1994-1749
1994
Groves, D.I.Taylor, W.R., Rock, N.M.S., Groves, D.I., et al.Geochemistry of Archean shoshonitic lamprophyres from the Yilgarn Block, western Australia: au abundance and association with gold mineralization.Applied Geochemistry, Vol. 9, pp. 197-222.AustraliaAlkaline rocks -Shoshonite, Lamprophyre
DS1994-1750
1994
Groves, D.I.Taylor, W.R., Rock, N.M.S., Groves, D.I., Perring, C.S., GoldingGeochemistry of Archean shoshonitic lamprophyres from the Yilgarn Block: gold abundance and association with gold mineralizationApplied Geochemistry, Vol. 9, pp. 197-222AustraliaAlkaline rocks -Shoshonite, Lamprophyre
DS1995-1315
1995
Groves, D.I.Muller, D., Groves, D.I.Potassic igneous rocks and associated gold-copper mineralizationSpringer Verlag Publishing Lecture Notes Vol. 56, 210p. $ 70.00 approxAustralia, Ontario, Papua New GuineaGold-copper, Characteristics, Deposits -Goodall, Tom's Gully,, Cadoman, BinghaM.
DS1995-1316
1995
Groves, D.I.Muller, D., Groves, D.I.Potassic igneous rocks and associated gold-copper mineralizationSpringer Verlag Lecture Notes, Vol. 56, 210p. $ 60.00GlobalLamproites, Kamafugites, Ultrapotassic, Group II, Lamprophyres -book emphasis gold-copper
DS1996-0378
1996
Groves, D.I.Dorling, S.L., Dentith, M.C., Groves, D.I., Playford, P.Heterogeneous brittle deformation in the Devonian carbonate rocks of the Pilbara range, Canning Basin...Australian Journal of Earth Sciences, Vol. 43, No. 1, Feb. pp. 15-20.AustraliaLennard Shelf, Structure, faulting, tectonics
DS1997-0105
1997
Groves, D.I.Bloem, E.J.M., Dalstra, H.J., Groves, D.I.Granitoid diapirism during protracted tectonism in an Archean granitoid greenstone belt, Yilgarn BlockPrecambrian Research, Vol. 85, No. 3-4, Dec. 1, pp. 147-AustraliaTectonics, Yilgarn greenstone belt
DS1997-0826
1997
Groves, D.I.Muller, D., Groves, D.I.Potassic igneous rocks and associated gold, copper mineralizationSpringer Revised edition (prev. 1995), 238p. approx. $ 70.00 United StatesGlobalBook - table of contents, Potassic rocks, alkaline rocks, lamprophyres
DS1999-0043
1999
Groves, D.I.Barley, M.E., Blake, T.S., Groves, D.I.The Mount Bruce megasequence set and eastern Yilgarn Craton: examples of late Archean and Early ProterozoicPrecambrian Research, Vol. 58, pp. 55-70.AustraliaCraton - Pilbara
DS2002-0607
2002
Groves, D.I.Grainger, C.J., Groves, D.I., Costa, C.H.G.The epigenetic sediment hosted Serra Pelada au PGE deposit and its potential genetic association ....Society of Economic Geologists Special Publication, No.9,pp.47-64.Brazil, Amazon CratonGold, platinum, iron oxide copper mineralization, Deposit - Serra Pelada, Carajas
DS2002-1665
2002
Groves, D.I.Vielreicher, N.M., Ridley, J.R., Groves, D.I.Marymia: an Archean, amphibolite facies hosted orogenic lode gold deposit overprinted by Paleoproterozoic....Mineralium Deposita, Vol.AustraliaMetallogeny - base metal mineralization, Deposit - Marymia
DS200412-0023
2004
Groves, D.I.Alvin, M.P., Dunphy, J.M., Groves, D.I.Nature and genesis of a carbonatite associated fluorite deposit at Speewash, East Kimberley region, western Australia.Mineralogy and Petrology, Vol. 80, 3-4, March pp. 127-153.AustraliaCarbonatite
DS200412-0682
2004
Groves, D.I.Goff, B.H., Weinberg, R., Groves, D.I., et al.The giant Vergenoeg fluorite deposit in a magnetite fluorite fayalite REE pipe: a hydrothermally altered carbonatite related pegMineralogy and Petrology, Vol. 80, 3-4, March pp. 173-199.Africa, South AfricaCarbonatite
DS200712-0389
2007
Groves, D.I.Groves, D.I., Bierlein, F.P.Geodynamic settings of mineral deposit systems. NOT specific to diamonds).Journal of the Geological Society, Vol. 164, 1, pp. 19-30.MantleGeodynamics
DS201212-0344
2012
Groves, D.I.Kabete, J.M., Groves, D.I., McNaughton, N.J., Mruma, A.H.A new tectonic and temporal framework for the Tanzanian shield: implications for gold metallogeny and undiscovered endowment.Ore Geology Reviews, Vol. 48, pp. 88-124.Africa, TanzaniaTectonics
DS202002-0203
2020
Groves, D.I.Liu, S., Fan, H-R., Groves, D.I., Yang, K-F, Yang, Z-F., Wang, Q-W.Multiphase carbonatite related magmatic and metasomatic processes in the genesis of the ore-hosting dolomite in the giant Bayan Obo REE-Nb-Fe deposit.Lithos, in press available, 96p. PdfChinacarbonatite

Abstract: The origin of dolomite that hosts the Bayan Obo REE-Nb-Fe deposit (57.4 Mt.@6% REE2O3, 2.16 [email protected]% Nb2O5, and >1500 Mt.@35% iron oxides) has been controversial for decades, but it is integral to understanding of the genesis of this giant deposit. In this study, based on the textures and in situ major and trace element composition of its carbonates, the dolomite was proved to be initially generated from magnesio-ferro?carbonatite melts. It subsequently experienced magmatic-hydrothermal alteration and recrystallization in a low strain environment, caused by calcio?carbonatitic fluids, with formation of finer-grained dolomite, interstitial calcite and increasing amounts of associated fluorocarbonates. Available stable isotope analyses indicate that the recrystallized ore-hosting dolomite has higher ?13C and ?18O ratios compared to its igneous coarse-grained precursor. Rayleigh fractionation during the recrystallization process, rather than crustal contamination, played a major role in the highly-variable stable isotope composition of carbonates in the dolomite. Low-T alteration increased variability with apparently random increases in ?18O within carbonates. The REE, Ba and Sr were added simultaneously with the elevated (La/Yb)cn from magnesio-ferro?carbonatite melts to calcio?carbonatitic fluids, and to carbonatite-derived aqueous fluids, through which extensive fluorine metasomatism and alkali alteration overlapped the recrystallization of the ore-hosting dolomite. Therefore, the multi-stage REE mineralization at Bayan Obo is closely related to metasomatism by calcio?carbonatitic fluids of previously-emplaced intrusive magnesio-ferro?carbonatite bodies during late evolution of the Bayan Obo carbonatite complex. Then, the ore-hosting dolomitic carbonatite was subjected to compressive tectonics during a Paleozoic subduction event, and suffered intense, largely brittle, deformation, which partially obscured the earlier recrystallization process. The complex, multi-stage evolution of the ore-hosting dolomite is responsible for the uniqueness, high grade and giant size of the Bayan Obo deposit, the world's largest single REE resource with million tonnes of REE oxides.
DS202009-1629
2020
Groves, D.I.Groves, D.I., Santosh, M.Craton and thick lithosphere margins: the sites of giant mineral deposits and mineral provinces. Not specific to diamonds.Gondwana Research, in press available 28p. PdfGlobalgeodynamics
DS201012-0258
2010
Groves, D.L.Gwalani, L.G., Rogers, K.A., Demeny, A., Groves, D.L., Ramsay, R., Beard, A., Downes, P.J., Eves, A.The Yungul carbonatite dykes associated with the epithermal fluorite deposit at Speewah, Kimberley, Australia: carbon and oxygen isotope constraints originMineralogy and Petrology, Vol. 98, 1-4, pp. 123-141.AustraliaCarbonatite
DS1991-1431
1991
Grow, I.A.Robbins, S.I., Grow, I.A.Isostatic residual anomaly gravity maps - a comparison of local versus regional compensation models in WyomingGeological Society of America Annual Meeting Abstract Volume, Vol. 23, No. 5, San Diego, p. A 317WyomingGravity, Models
DS1989-0010
1989
Grow, J.A.Agena, W.F., Lee, M.W., Grow, J.A.Reprocessing of the COCORP dat a recorded across the Wichita Mountain Uplift and the Anadarko Basin in southern OklahomaUnited States Geological Survey (USGS) Open File, No. 89-0357, 20p. $ 3.50GlobalGeophysics, Tectonics -COCORP
DS201510-1804
2015
Groza, L.G.Smith, L.j.D., Ptacek, C.J., Blowes, D.W., Groza, L.G., Moncur, M.C.Perchlorate in lake water from an operating mine. DiavikEnvironmental Science and Technology, Vol. 49, 13, pp. 7589-7596.Canada, Northwest TerritoriesDeposit - Diavik

Abstract: Mining-related perchlorate [ClO4(-)] in the receiving environment was investigated at the operating open-pit and underground Diavik diamond mine, Northwest Territories, Canada. Samples were collected over four years and ClO4(-) was measured in various mine waters, the 560 km(2) ultraoligotrophic receiving lake, background lake water and snow distal from the mine. Groundwaters from the underground mine had variable ClO4(-) concentrations, up to 157 ?g L(-1), and were typically an order of magnitude higher than concentrations in combined mine waters prior to treatment and discharge to the lake. Snow core samples had a mean ClO4(-) concentration of 0.021 ?g L(-1) (n=16). Snow and lake water Cl(-)/ClO4(-) ratios suggest evapoconcentration was not an important process affecting lake ClO4(-) concentrations. The multiyear mean ClO4(-) concentrations in the lake were 0.30 ?g L(-1) (n = 114) in open water and 0.24 ?g L(-1) (n = 107) under ice, much below the Canadian drinking water guideline of 6 ?g L(-1). Receiving lake concentrations of ClO4(-) generally decreased year over year and ClO4(-) was not likely [biogeo]chemically attenuated within the receiving lake. The discharge of treated mine water was shown to contribute mining-related ClO4(-) to the lake and the low concentrations after 12 years of mining were attributed to the large volume of the receiving lake.
DS1996-0878
1996
GRQ Mining Inc.Mann, A.G., GRQ Mining Inc.Geological report on Dog river industrial mineral permit 9392060004 Fort Smith 74 M 14Alberta Geological Survey, MIN 19960020AlbertaExploration - assessment
DS1984-0323
1984
Gruau, G.Gruau, G., Martin, H., Leveque, B., Capdevila, R., Marot, A.Rubidium-strontium and Samarium-neodymium (sm-nd) Geochronology of Lower proterozoic Granite Greenstone Terrains in French Guiana, South America.B.r.g.m., IN PRESSSouth America, French GuianaBlank
DS1984-0482
1984
Gruau, G.Marot, A., Capdevila, R., Leveque, B., Gruau, G., Martin, G., Cha.Le Synclinorium du Sud de Guyane Francaise: une Ceinture Deroches Vertes D'age Proterozoic Inferieur.Annual DES SCIENCES DE la TERRE, 10TH. SESSION HELD BORDEAU, South America, GuyanaBlank
DS1991-1742
1991
Gruau, G.Tourpin, S., Gruau, G., Blais, S., Fourcade, S.Resetting of rare earth elements (REE) and neodymium and Strontium isotopes during carbonization of a komatiite flow from FinlandChemical Geology, Vol. 90, No. 1-2 March 25, pp. 15-30FinlandKomatiite, Alteration
DS1991-1743
1991
Gruau, G.Tourpin, S., Gruau, G., Blais, S., Fourcade, S.Resetting of rare earth elements (REE) and neodymium and StrontiumChemical Geology, Vol. 90, No. 1-2 March 25, pp. 15-30FinlandKomatiite, Alteration
DS1993-0899
1993
Gruau, G.Lecuyer, C., Gruau, G., Anhaeusser, C.R., Fourcade, S.The origin of fluids and the effects of metamorphism on the primary chemical compositions of Barberton komatiites: new evidence from geochemistry, isotopesEconomic Geology Research Unit, University of the Witwatersrand, Inf. Circular No. 272, 32pSouth AfricaGeochemistry, Komatiites
DS1994-1011
1994
Gruau, G.Lecuyer, C., Gruau, G., Anhaeusser, C.R., Fourcade, S.The origin of fluids and effects of metamorphism on the primary chemical compositions of Barberton komatiites: new evidenceGeochimica et Cosmochimica Acta, Vol. 58, No. 2, January pp. 1043South AfricaGeochemistry, Geochronology
DS1995-0692
1995
Gruau, G.Gruau, G., et al.Extreme isotopic signatures in carbonatites from Newania RajasthanTerra Nova, Abstract Vol., p. 336.IndiaGeochronology, Carbonatite
DS1995-1044
1995
Gruau, G.Lahaye, Y., Arndt, N., Gruau, G.The influence of alteration on the trace element and neodymium isotopic compositions of komatiitesChemical Geology, Vol. 126, No. 1, Nov. 20, pp. 43-64AustraliaKomatiites, Alteration, Metasomatism
DS1997-0098
1997
Gruau, G.Bernard-Griffiths, J., Gruau, G., Mace, J.Continental lithospheric contribution to alkaline magmatism: isotopic Sr, lead) and geochemical rare earth elements (REE).Journal of Petrology, Vol. 38, No. 1, Jan. 1, pp. 115-132.MantleSerra de Monchique, Mount Ormonde, Alkaline rocks
DS1998-0679
1998
Gruau, G.Jahn, B.M., Gruau, G., Rudnik, V.A.Archean crustal evolution of the Aldan Shield, Siberia: geochemical and isotopic constraints.Precambrian Research, Vol. 91, No. 3-4, Aug. pp. 333-364.Russia, Siberia, Aldan ShieldGeochronology, Geochemistry
DS1999-0271
1999
Gruau, G.Gruau, G., Bernard Griffiths, J., Lecuyer, C.The origin of U shaped rare earth patterns in ophiolite peridotites:assessing the role of secondary alterationGeochimica et Cosmochimica Acta, Vol. 62, No. 21-22, Nov. pp, 3545-60.CaliforniaMelt rock reaction, Trinity ophiolite - harzburgite, lherzolite
DS200412-0164
2004
Gruau, G.Blichert-Toft, J., Arndt, N.T., Gruau, G.Hf isotopic measurements on Barberton komatiites: effects of incomplete sample dissolution and importance for primary and secondChemical Geology, Vol. 207, 3-4, July 16, pp. 261-275.Africa, South AfricaGeochronology - not specific to diamonds
DS2001-0416
2001
Grubaugh, K.Grubaugh, K.Ghana: gold, diamonds and moreSociety for Mining, Metallurgy and Exploration (SME) Preprint, 01-122, 6p.GhanaExploration - discoveries, mining
DS1991-0618
1991
Grubb, M.D.Grubb, M.D., McCallum, M.E.Genesis of diamond placers on the Guiana shield, South AmericaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 151-153GuyanaIssineru-Enachu district, Roraima Group, geomorphology
DS1989-0062
1989
Grubb, P.L.C.Balasubramaniam, K.S., Faure, G., Goni, J., Grubb, P.L.C.Weathering : its products and deposits.Vol. 1. processes. Vol. IIGeotechnicsAugustithis Publishing, (Greece), Vol. I 462p. $ 50.00 Vol. II 672p. $ 65.00GlobalWeathering, Deposits -processes
DS202101-0014
2020
Gruber, B.Gruber, B., Chacko, T., Pearson, D.G., Currie, C., Menzies, A.Heat production and moho temperatures in cratonic crust: evidence from lower crustal xenoliths from the Slave craton.Lithos, doi.org/10.1016/ j.lithos.2020.105889 13p. PdfCanada, Northwest Territoriesdeposit - Diavik A-154

Abstract: Ambient Moho temperatures and lower crustal heat production are surprisingly poorly constrained in cratons. Here we address these problems using 15 lower crustal xenoliths from the Diavik A-154 kimberlite, Slave craton, Canada. Iron?magnesium exchange geothermometry on small biotite and amphibole inclusions in garnet indicates that the Slave craton lower crust was at a temperature of ?500 °C at the time of kimberlite eruption (~55 Ma). The ambient lower crustal temperature was likely lower than 500 °C because the thermometers record the closure temperature of diffusional Fe2+-Mg exchange between touching mineral pairs. New measurements of K, U and Th concentrations in the constituent minerals, together with xenolith modes, allow reconstruction of the heat-producing element (HPE) K, U, and Th budget of the Slave craton lower crust. Metasedimentary granulites have an average heat production of 0.29 ± 0.01 ?W/m3 (n = 3) whereas mafic granulites have an average heat production of 0.13 ± 0.03 ?W/m3 (n = 12). Our new data clearly show that plagioclase abundance in both lithologies has a major influence on overall lower crustal heat production, being an important reservoir of all three HPE. Combining the heat production of mafic and metasedimentary granulites in their observed 80:20 proportions results in an average heat production value for the Slave craton lower crust of 0.16 ± 0.03 ?W/m3. Using these heat production estimates, modeled Moho temperatures beneath Diavik of ~450-470 °C are broadly consistent with maximum lower crustal temperatures indicated by geothermometry. The low HPE contents predicted for cratonic lower crust must result in lower temperatures in the deep crust and mantle lithosphere, and in turn higher estimates for the thickness of mantle lithosphere. This effect becomes larger as the thickness of the low-HPE lower crustal layer increases. In the specific case of the central Slave craton, we find that model estimates of the diamond potential of the mantle lithosphere, as judged by the proportion of lithospheric mantle in the diamond stability field, are not strongly affected by small variations in lower crustal heat production and Moho temperature.
DS201812-2813
2018
Gruber, B.H.Gruber, B.H., Chacko, T., Pearson, D.G.The thermochemical conditions of the Diavik lower crust: a kimberlite-hosted xenolith study.2018 Yellowknife Geoscience Forum , p. 25-26. abstractCanada, Northwest Territoriesdeposit - Diavik

Abstract: Thermochemical variables such as lower crustal heat production and Moho temperatures in cratonic regions offer critical insight in constraining the thermal and geodynamic evolution of the lithosphere. In this study, 15 lower crustal granulite xenoliths erupted via the A154N kimberlite at the Diavik mine in the NWT, Canada were studied to quantify the thermal properties of the local Moho and the effects of different heat production models on geotherm models. We quantitatively constrain the thermal properties of the local Moho and the effects of different heat production models on ancient Moho temperatures, the effects of crustal thickness on Moho temperatures, and potential lower crustal compositions. We evaluate the effect of these parameters on total lithospheric thickness estimates. In order to test the accuracy of deep crust thermal calculations, we estimated the ambient temperature of the lower crust at the time of kimberlite eruption through garnet-biotite Fe-Mg exchange geothermometry (Ferry & Spear, 1978). Rim compositions from touching garnet-biotite pairs were used in the calculations and yielded temperatures of 524 ± 77°C (n=20). These represent a maximum estimate of the ambient lower crustal temperature as the closure temperature of garnet-biotite Fe-Mg exchange between garnet and biotite may be higher than the ambient temperature. The primary objective of this study is to quantify lower crustal heat production and its effects on the thermal architecture of cratons. The concentrations of the main heat-producing elements (HPEs) U, Th, and K were quantified via LA-ICP-MS and EPMA in multiple mineral phases per xenolith. By combining these measurements with mineral modes, we derived reconstructed bulk-rock HPE concentrations that were utilized to calculate a range of lower crustal heat production values. This method is preferred over whole-rock analyses as 1) kimberlite is generally enriched in HPEs (Tappe et al. 2013) and can bias trace-element data for their xenoliths and 2) data on individual minerals allows for theoretical lower crustal compositions to be calculated on an idealized basis. A lower crust comprising exclusively mafic granulite (garnet, plagioclase, clinopyroxene ± orthopyroxene) provides a lower bound to heat production (0.07 ± 0.04 W/m3) whereas a lower crust made exclusively of high-grade metasedimentary rocks yields an upper bound (0.42 ± 0.08 W/m3). Both endmembers are present as xenoliths in the A154N kimberlite but mafic granulites predominate following the worldwide trend (Rudnick, 1992). We model the lower crust comprising 20% metasedimentary granulites and 80 % depleted mafic granulites, in accordance with the present xenolith collection. Using this preferred crustal model, we calculate an average heat production of 0.12 ± 0.05 W/m3) for the lower crust beneath Lac de Gras. Utilizing heat flow measurements (Russell et thickness estimates (Mareschal et al. 2004) in conjunction with these HPE determinations, the Moho temperature underlying A-154N can be calculated to be 502 ± 10°C. Using these values along with available mantle xenolith thermobaromtetry (Hasterok & Chapman, 2011) the geotherm is extrapolated to present a mantle potential temperature of 1365°C, at 200 km (FITPLOT, Mather et al, 2011).
DS202004-0517
2019
Gruber, B.H.Gruber, B.H.Temperatures and heat production in the Slave Craton lower crust: evidence from exnoliths in the Diavik A-154 kimberlite.Thesis MSc University of Alberta , 123p. Pdf Canada, Northwest Territoriesdeposit - Diavik A-154

Abstract: Lower crustal heat production is poorly constrained due to the relative inaccessibility of lower crustal samples and their inherent complexity. To obtain the requisite information, the current project conducts spatially resolved geochemical analyses on minerals in 15 lower crustal xenoliths erupted via the Diavik A-154 kimberlite of the Northwest Territories, Canada. The aims are to: 1) conduct geothermometric measurements on lower crustal minerals, 2) construct a heatproducing element budget of the lower crust of the Slave craton, and 3) test the validity of these measurements in a parameter space relevant to geodynamic modeling and diamond exploration. The Diavik lower crustal xenolith suite comprises two main lithologies, mafic granulite (garnet-plagioclase-clinopyroxene ± orthopyroxene) and metasedimentary granulite (garnetplagioclase- orthopyroxene ± quartz ± K-feldspar ± kyanite), which are present in proportions of approximately 80:20, respectively. Application of mineral-pair, iron-magnesium exchange geothermometers (garnet-biotite, garnet-amphibole, and garnet-clinopyroxene) to these xenoliths indicates that the lower crust was at a maximum temperature of roughly 500 °C at the time of kimberlite eruption (~ 55 Ma). The actual temperature of the lower crust is likely lower than 500 °C as the geothermometers probably record the closure temperature of diffusional Fe2+-Mg exchange between touching mineral pairs rather than the ambient temperature of the rocks prior to their entrainment in the kimberlite magma. Heat-producing element (HPE) concentration measurements show that the lower crustal heat production of the Slave craton is likely 0.14 ± 0.02 ?W/m3, which is lower than most values in the literature but broadly comparable to some geophysical estimates. This estimate is the result of (20:80) bimodal mixing of idealized lower crustal endmembers: a metasedimentary lower crust (0.37 ± 0.06 ?W/m3) and a mafic lower crust (0.08 ± 0.01 ?W/m3). These endmembers were iii calculated via a reconstructed bulk rock calculation utilizing trace element concentrations of constituent lower crustal minerals and idealized lithologies from the lower crustal xenoliths. Using these heat production estimates and other crustal parameters such as continental heat flux, mantle heat flux, crustal thickness, and crustal thermal conductivity, I modeled a Moho temperature for the Slave craton of 425 °C, which is consistent with maximum lower crustal temperature estimate given by geothermometry. Adjusting the lower crustal heat production in the geotherm modeling program FITPLOT changes the temperature of the Moho in a similar fashion to the calculated models; however, the diamond propensity of the mantle lithosphere (partially a function of Moho temperature and heat production) does not appear to be strongly affected by a changing Moho temperature and is more strongly controlled by the conditions of the mantle P-T array.
DS1999-0272
1999
Grubler, A.Grubler, A., Nakicenovic, N., Victor, D.G.Dynamics of energy technologies and global changeEnergy Policy, Vol. 27, pp. 247-80.GlobalGlobal warming, Modelling - changes, energy
DS200512-0372
2005
Gruen, D.M.Gruen, D.M., Shenderova, O.A., Vul, A.Y.Synthesis, properties and applications of ultrananocrystalline diamond.Springer, 401p. $ 89. ISBN 1-4020-3321-4Book - nanodiamonds
DS1985-0252
1985
Grueninger, H.R.V.Grueninger, H.R.V.Planet of a different hue. a structural history of the earth.Translation from GermanPrivately Publ, 100pGlobalCraton
DS2001-0907
2001
GruffatPereira, F., Bilal, E., Moutte, Lapido, Gruffat, AlbertDissolution of apatite ore from Angico Dos Dias carbonatite Complex and recovery of rare earth elementsJournal of South African Earth Sciences, Vol. 32, No. 1, p. A 28.(abs)BrazilCarbonatite, Angico Dos Dias
DS1990-0608
1990
Gruijter, J.J.deGruijter, J.J.de, Braak, C.J.F.Model-free estimation from spatial samples: are appraisal of classical sampling theoryMathematical Geology, Vol. 22, No. 4, May pp. 407-416GlobalGeostatistics, Sampling theory
DS200412-1790
2004
Grujic, D.Seward, D., Grujic, D., Scheurs, G.An insight into the breakup of Gondwana: identifying events through low temperature thermochronology from the basement rocks ofTectonics, Vol. 23, 3, June 8, TC3007 10.1029/2003 TC001556Africa, MadagascarTectonics
DS201610-1840
2016
Grujic, M.Aravanis, T., Chen, J., Fuechsle, M., Grujic, M., Johnston, P., Kok, Y., Magaraggia, R., Mann, A., Mann, L., McIntoshm S., Rheinberger, G., Saxey, D., Smalley, M., van Kann, F., Walker, G., Winterflood, J.VK1 tm - a next generation airborne gravity gradiometer.ASEG-PESA-AIG 2016 25th Geophysical Conference, Abstract 5p.TechnologyGradiometer

Abstract: The minerals exploration industry’s demand for a highly precise airborne gravity gradiometer has driven development of the VK1TM Airborne Gravity Gradiometer, a collaborative effort by Rio Tinto and the University of Western Australia. VK1TM aims to provide gravity gradient data with lower uncertainty and higher spatial resolution than current commercial systems. In the recent years of VK1TM development, there have been significant improvements in hardware, signal processing and data processing which have combined to result in a complete AGG system that is approaching competitive survey-ready status. This paper focuses on recent improvements. Milestone-achieving data from recent lab-based and moving-platform trials will be presented and discussed, along with details of some advanced data processing techniques that are required to make the most use of the data.
DS1999-0730
1999
Grundvig, S.Tegner, C., Robins, B., Grundvig, S.Assimilation of crustal xenoliths in a basaltic magma chamber: Strontium and neodymium isotopic constraints... Hasvik...Journal of Petrology, Vol. 40, No. 3, Mar. pp; 363-80.NorwayLayered intrusion - xenoliths, Geochronology
DS201905-1019
2019
Grundy, R.Canil, D., Grundy, R., Johnston, S.T.Thermal history of the Donjek harzburgite massif in ophiolite from Yukon, Canada with implications for the cooling of oceanic mantle lithosphere.Lithos, Vol. 328-329, pp. 33-42.Canada, Yukongeothermometry

Abstract: We examine the partial melting and the cooling history of a ~5?km section of mantle lithosphere preserved in the Donjek massif, part of a Permian ophiolite in the northern Cordillera of Yukon, Canada. The mantle rocks are depleted spinel harzburgite containing <3% clinopyroxene displaying steep rare-earth element (REE) chondrite-normalized profiles and low (Gd/Yb)n (0.02 to 0.07) compared to most other ophiolites. The REE patterns of clinopyroxene can be modeled as 16-20% partial melts of typical depleted mid-ocean ridge (MOR) mantle. The REE exchange between coexisting ortho- and clinopyroxene preserves temperatures (TREE) of 1150-1360?°C, some of the highest values recorded in ophiolites and abyssal peridotites, and show a positive correlation with CaMg exchange (solvus) temperatures (TBKN) of 900-970?°C. The harzburgite represents lithosphere formed at an initial melting temperature of ~ 1350?°C that cooled at rate of 10?1 to 10?4?°C/year as deduced by TREE values with cation diffusion and grain size data. The TREE temperatures and cooling rates for the Donjek massif show a regular systematic variation with depth from the crust-mantle transition along a trend similar to the Samail ophiolite of Oman, consistent with conductive heat transfer beneath a cool lower crust. High near-solidus temperatures and the cooling rates in the massif were a consequence of rapid obduction against oceanic crust along either a transform or low angle detachment soon after melt extraction. Final emplacement of the ophiolite as klippen on underlying continental crust occurred ~ 40?m.y. later.
DS1975-1030
1979
Grunenfelder, M.Gebauer, D., Grunenfelder, M.Uranium-lead-zirconium and Rubidium-strontium Mineral Dating of eclogites and Their Country Rocks. Example: Munchberg Gneiss Massif, Northeast bavaria.Earth and Planetary Science Letters, Vol. 42, PP. 35-44.GlobalRelated Rocks
DS1983-0600
1983
Grunenfelder, M.H.Tilton, G.R., Grunenfelder, M.H.Lead Isotope Relationships in Billion Year Old Carbonatite Complexes Superior Province, Canadian Shield.Geological Society of America (GSA), Vol. 15, No. 6, P. 707. (abstract.).Canada, Ontario, SuperiorRelated Rocks, Geochronology, Killala, Firesand
DS1986-0313
1986
Grunenfelder, M.H.Grunenfelder, M.H., Tilton, G.R., Bell, K., Blenkinsop, J.Lead and strontium isotope relationship in the Oka carbonatitecomplex, QuebecGeochimica et Cosmochimica Acta, Vol. 50, pp. 461-468Quebec, UgandaMelilite, Carbonatite
DS1989-0839
1989
Grunenfelder, M.H.Kwon, S.T., Tilton, G.R., Grunenfelder, M.H.Lead isotope relationships in carbonatites and alkalic complexes: anoverviewCarbonatites -Genesis and Evolution, Ed. K. Bell Unwin Hyman Publ, pp. 360-387Midcontinent, OntarioGeochronology, Lead
DS2001-0417
2001
Grunewald, S.Grunewald, S., Weber, M., Kind, R.The upper mantle under Central Europe - indications for the Eifel plumeGeophysical Journal International, Vol. 147, No. 3, pp. 590-601.EuropeGeophysics, Hot spot
DS201910-2262
2019
Gruninger, H.Gruninger, H., Liu, Z., Siegel, R., Boffa Ballaran, T., Katsura, T., Senker, J., Frost, F.J.Oxygen vacancy ordering in aluminous bridgmanite in the Earth's lower mantle.Geophysical Research Letters, Vol. 46, 15, pp. 8731-8740.Mantlebridgmanite

Abstract: The lower mantle encompasses the largest region of the Earth's interior and is mainly composed of the perovskite?structured mineral (Mg,Fe,Al)(Al,Si)O3 bridgmanite. Its properties, therefore, control both the diffusive transport of elements and solid state flow in the lower mantle, which will be strongly influenced by point defects. We have identified and quantified defects in bridgmanite that arise from the replacement of silicon by aluminum and result in the creation of a vacant oxygen site. These oxygen defects are also found to form clusters in the structure, which in other perovskite structured minerals have been shown to strongly affect physical properties. As defect formation and ordering is dependent on composition and pressure, strong variations in physical properties may be expected within the upper 300 km of the lower mantle.
DS1996-0420
1996
Grunow, A.Encarnacion, J., Grunow, A.Changing magmatic and tectonic styles alone the paleo-Pacific margin of Gondwana and the onset of early Paleozoic magmatism in Antarctica.Tectonics, Vol. 13, No. 6, Dec. pp. 1325-41.AntarcticaTectonics, Magmatism
DS1996-0573
1996
Grunow, A.Grunow, A., Hanson, R., Wilson, T.Were aspects of Pan-African deformation linked to Iapetus opening?Geology, Vol. 24, No. 12, Dec. pp. 1063-66.Africa, South America, IndiaTectonics, Paleomagnetics
DS1992-0626
1992
Grunow, A.M.Grunow, A.M., Dalziel, I.W.D., Harrison, T.M., Heizler, M.T.Structural geology and geochronology of subduction complexes along the margin of Gondwanaland: new dat a from the Antarctic Peninsula and southernmostAndesGeological Society of America (GSA) Bulletin, Vol. 104, No. 11, November pp. 1497-1514Andes, AntarcticaStructure, Geochronology
DS1997-1263
1997
Grunow, A.M.Wilson, T.J., Grunow, A.M., Hanson, R.E.Gondwana assembly: the view from southern Africa and East GondwanaJournal of Geodynamics, Vol. 23, No. 3-4, pp. 263-286.Africa, South AfricaTectonics, Terranes
DS1998-0540
1998
Grunow, A.M.Grunow, A.M.Paleomagnetism and Gondwana's major and microplate motionsJournal of African Earth Sciences, Vol. 27, 1A, p. 96. AbstractGondwanaPaleomagnetics, Tectonics
DS1999-0273
1999
Grunow, A.M.Grunow, A.M.Gondwana events and paleogeography: a paleomagnetic reviewJournal of African Earth Sciences, Vol. 28, No. 1, pp. 53-69.Tectonics, Geophysics - paleomagnetics
DS1999-0274
1999
Grunsky, E.Grunsky, E.Buffalo Head Hills diamond add sparkle to Alberta explorationProspectors and Developers Association of Canada (PDAC) Exploration and Dev. Highlights, March pp. 23-24.AlbertaOveriew - brief, Diamond exploration
DS2001-0289
2001
Grunsky, E.Eccles, R., Grunsky, E.Alteration mineralogy of Alberta kimberlites. PIMA infrared spectroscopic analysisAlberta Geological Survey, www.ags.gov.ab.ca, SPE 12, $ 20.AlbertaMineralogy, Spectroscopy
DS2001-1050
2001
Grunsky, E.Seneshen, D., Grunsky, E., Rencz, A., Hall, G., Dunn, C.Geochemical exploration for kimberlites in northern Alberta37th. Forum Industrial Minerals;, May 23-5, pp. 33-4.AlbertaGeochemistry
DS201312-0442
2013
Grunsky, E.Johnson, C.L., Ross, M., Grunsky, E., Hodder, T.J.Fingerprinting glacial processes for diamond exploration on Baffin Island.Geoscience Forum 40 NWT, Poster abstract only p. 62Canada, Nunavut, Baffin IslandGeomorphology
DS201511-1841
2015
Grunsky, E.Harris, J.R., Grunsky, E., Behnia, P., Corrigan, D.Dat a and knowledge-driven mineral prospectivity maps for Canada's north. (**note for Au )Ore Geology Reviews, Vol. 71, pp. 788-803.Canada, Nunavut, Melville PeninsulaGIS. IAS

Abstract: Data- and knowledge-driven techniques are used to produce regional Au prospectivity maps of a portion of Melville Peninsula, Northern Canada using geophysical and geochemical data. These basic datasets typically exist for large portions of Canada's North and are suitable for a "greenfields" exploration programme. The data-driven method involves the use of the Random Forest (RF) supervised classifier, a relatively new technique that has recently been applied to mineral potential modelling while the knowledge-driven technique makes use of weighted-index overlay, commonly used in GIS spatial modelling studies. We use the location of known Au occurrences to train the RF classifier and calculate the signature of Au occurrences as a group from non-occurrences using the basic geoscience dataset. The RF classification outperformed the knowledge-based model with respect to prediction of the known Au occurrences. The geochemical data in general were more predictive of the known Au occurrences than the geophysical data. A data-driven approach such as RF for the production of regional Au prospectivity maps is recommended provided that a sufficient number of training areas (known Au occurrences) exist.
DS2000-0259
2000
Grunsky, E.C.Eccles, D.R., Grunsky, E.C., Grobe, M., Weiss, J.Structural emplacement model for kimberlitic diatremes in northern AlbertaAlberta Energy and Utilities Board and Alberta Geological Survey, Report, 116p.AlbertaStructure - model
DS2000-0260
2000
Grunsky, E.C.Eccles, D.R., Grunsky, E.C., Grobe, M., Weiss, J.Structural emplacement model for kimberlitic diatremes in AlbertaGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Calgary May 2000, 1p.AlbertaStructure -, Deposit - Buffalo Hills area
DS2001-0877
2001
Grunsky, E.C.Paganelli, F., Grunsky, E.C., Richards, J.P.Radarset Land sat 7 Thematic Mapper integration for kimberlite exploration in the Buffalo Head Hills area.Geological Association of Canada (GAC) Annual Meeting Abstracts, Vol. 26, p. 110-11.abstract.AlbertaRemote sensing - LANDSAT.
DS2001-0878
2001
Grunsky, E.C.Paganelli, F., Grunsky, E.C., Richards, J.P.Structural emplacement of RADARSAT-1 principal component imagery and its potential application to kimberlitic exploration in the Buffalo Head Hills area.Alberta Energy and Utilities Board and Alberta Geological Survey, Report 2001-03, 47p.Alberta, north centralStructure - model
DS2002-0618
2002
Grunsky, E.C.Grunsky, E.C.R: a dat a analysis and statistical programming environment - an emerging tool for the geosciences.Computers and Geosciences, Vol. 28, 10, pp.1219-22.GlobalComputers - programs
DS2002-1201
2002
Grunsky, E.C.Paganelli, F., Richards, J.P., Grunsky, E.C.Integration of Structural, Gravity and Magnetic Dat a Using the Weights of EvidenceNatural Resources Research, Vol. 11, No. 3, pp. 219-236northern central AlbertaWeights of evidence method, favourability, kimberlite exploration, Buffalo
DS2002-1202
2002
Grunsky, E.C.Pagnelli, F., Richards, J.P., Grunsky, E.C.Integration of structural, gravity and magnetic dat a using the weights of evidenceNatural Resources Research, Vol. 11,3,pp. 219-36.AlbertaGeophysics - gravity, magnetics, Exploration techniques
DS2003-0443
2003
Grunsky, E.C.Garrett, R.G., Grunsky, E.C.S and R functions for the display of Thompson Howarth plotsComputers and Geosciences, Vol. 29, 2, pp. 239-42.GlobalComputer - program
DS2003-0509
2003
Grunsky, E.C.Grunsky, E.C., Smee, B.W.Enhancements in the interpretation of geochemical dat a using multivariate methods andCanadian Institute Mining and Metallurgy Bulletin, Vol. 96, No.1068, Feb. pp. 39-43.GlobalGeochemistry - techniques, exploration - not specific t
DS200412-0611
2003
Grunsky, E.C.Garrett, R.G., Grunsky, E.C.S and R functions for the display of Thompson Howarth plots.Computers & Geosciences, Vol. 29, 2, pp. 239-42.TechnologyComputer - program
DS200512-0117
2005
Grunsky, E.C.Brown, O.H., Utting, D.J., Little, E.C., Grunsky, E.C., Harris, J., Peter, P.Remote predictive mapping of surficial geology in Nunavut using supervised classification techniques of Land sat and RADARSAT I data.GAC Annual Meeting Halifax May 15-19, Abstract 1p.Canada, NunavutRemote sensing
DS200712-0390
2007
Grunsky, E.C.Grunsky, E.C.The interpretation of regional geochemical survey data. ( not specific to diamonds.... good review.Proceedings of Exploration 07 edited by B. Milkereit, pp. 139-182.TechnologyGeochemistry - review
DS200812-0433
2008
Grunsky, E.C.Grunsky, E.C., Kjarsgaard, B.A.Classification of distinct eruptive phases of the Diamondiferous Star kimberlite, Sask. based on statistical treatment whole rock geochemical analyses.Applied Geochemistry, in press available.Canada, SaskatchewanClassification - geochemistry - Star
DS200812-0434
2008
Grunsky, E.C.Grunsky, E.C., Kjarsgaard, B.A.Classification of distinct eruptive phases of the Diamondiferous Star kimberlite, Saskatchewan, Canada based on statistical treatment of whole rock geochemical analyses.Applied Geochemistry, Vol. 23, 12, pp. 3321-3336.Canada, SaskatchewanDeposit - Star
DS201012-0252
2010
Grunsky, E.C.Grunsky, E.C.The interpretation of geochemical survey data.Geochemistry, Vol. 10, no. 1, pp. 27-74.TechnologyQuality control - not specific to diamonds
DS201412-0323
2011
Grunsky, E.C.Grunsky, E.C., Kjarsgaard, B.A., Kurzlaukis, S., Seller, M.The use of statistical methods applied to multi-element geochemistry for phase discrimination in kimberlites - examples from the Star and Whiskey kimberlites.GAC/MAC joint annual meeting, Vol. 36, p. 1. abstractCanada, Saskatchewan, OntarioGeochemistry - whole rock
DS201412-0654
2002
Grunsky, E.C.Paganelli, F., Richards, J.P., Grunsky, E.C.Integration of structural, gravity and magnetic dat a using the weights of evidence method as a tool for kimberlite exploration in the Buffalo Head Hills, northern central Alberta CanadaNatural Resources Research, Vol. 11, 3, pp. 219-Canada, AlbertaGeophysics
DS201912-2787
2019
Grunsky, E.C.Grunsky, E.C., de Caritat, P.State of the art analysis of geochemical data for mineral exploration. ( not specific to diamonds)Geochemistry: Exploration, Environment, Analysis, http://doi.org/10.1144/ geochem2019-031 16p. PdfCanada, Nunavut, Australiageochemistry

Abstract: Multi-element geochemical surveys of rocks, soils, stream/lake/floodplain sediments and regolith are typically carried out at continental, regional and local scales. The chemistry of these materials is defined by their primary mineral assemblages and their subsequent modification by comminution and weathering. Modern geochemical datasets represent a multi-dimensional geochemical space that can be studied using multivariate statistical methods from which patterns reflecting geochemical/geological processes are described (process discovery). These patterns form the basis from which probabilistic predictive maps are created (process validation). Processing geochemical survey data requires a systematic approach to effectively interpret the multi-dimensional data in a meaningful way. Problems that are typically associated with geochemical data include closure, missing values, censoring, merging, levelling different datasets and adequate spatial sample design. Recent developments in advanced multivariate analytics, geospatial analysis and mapping provide an effective framework to analyse and interpret geochemical datasets. Geochemical and geological processes can often be recognized through the use of data discovery procedures such as the application of principal component analysis. Classification and predictive procedures can be used to confirm lithological variability, alteration and mineralization. Geochemical survey data of lake/till sediments from Canada and of floodplain sediments from Australia show that predictive maps of bedrock and regolith processes can be generated. Upscaling a multivariate statistics-based prospectivity analysis for arc-related Cu-Au mineralization from a regional survey in the southern Thomson Orogen in Australia to the continental scale, reveals a number of regions with a similar (or stronger) multivariate response and hence potentially similar (or higher) mineral potential throughout Australia.
DS2000-0261
2000
Grunsky, E.G.Eccles, D.R., Grunsky, E.G., Grobe, M., Weiss, J.Structural emplacement model for kimberlitic diatremes in northern Alberta28th. Yellowknife Geoscience Forum, p. 22-24.abstractAlbertaStructure, Buffalo Hills area
DS201412-0322
2013
Grunsky, EC.Grunsky, EC., Kjarsgaard, B.A., Kurzlaukis, S., Seller, M., Knight, R., Moroz, M.Classification of whole rock geochemistry based on statistical treatment of whole rock geochemical analyses and portable XRF analyses at the Attawapiskat kimberlite field of Ontario.Geological Survey of Canada, Scientific Presentation 15,, 1 sheet 10.4095/292446Canada, Ontario, AttawapiskatGeochemistry - whole rock
DS2000-0364
2000
Gruosi, F.Gruosi, F.The black diamond. Art book with illustrationsDe Grosogono Publishing, $ 70.00 United StatesGlobalBook - ad, Black diamonds
DS2003-0526
2003
GrutterGurney, J.L., Baumgartner, M., Anckar, E., Gurney, J.J., Nowicki, T.E., GrutterKimberlite almanac8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractSouth AfricaDeposit - Finsch
DS200912-0522
2009
GrutterMuller, M.R., Jones, Evans, Grutter, Hatton, Garcia, Hamilton, Miensopust, Cole, Ngwisanyi, Hutchins, Fourie, Jelsma,Aravanis.Pettit, Webb, WasborgLithospheric structure, evolution and diamond prospectivity of the Rehoboth Terrane and western Kaapvaal Craton, southern Africa: constraints from broadbandLithos, In press - available 57p..Africa, South Africa, BotswanaGeophysics - broadband magnetotellurics
DS2003-0086
2003
Grutter, H.Baumgartner, M., Ankar, E., Grutter, H.Compositional classification of kimberlitic and non-kimberlitic ilmenite with implications8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, AbstractGlobalDiamond exploration - mineralogy
DS2003-0300
2003
Grutter, H.Creaser, R.A., Grutter, H., Carlson, J., Crawford, B.Macrocrystal phlogopite Rb Sr dates for the Ekati Province kimberlites, Slave8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, AbstractNorthwest TerritoriesKimberlite petrogenesis, Geochronology
DS2003-0320
2003
Grutter, H.Davis, W.J., Jones, A.G., Bleeker, W., Grutter, H.Lithosphere development in the Slave Craton: a linked crustal and mantle perspectiveLithos, Vol. 71, 2-4, pp. 575-589.Northwest Territories, NunavutTectonics
DS2003-0510
2003
Grutter, H.Grutter, H.Advanced indicator mineral chemistry techniques in diamond explorationPdac Abstract 2003, March 12, 1p.GlobalTechnology - indicators
DS2003-0511
2003
Grutter, H.Grutter, H., et al.Early-stage assessment of kimberlites using indicator minerals, petrography andQuebec Exploration 2003, diamond session, diamond session, extended abstract, 1 pageGlobalcore logging, important factors to assess diamond potential
DS2003-0512
2003
Grutter, H.Grutter, H., Gurney, J., Nowicki, T., Moore, R.Early stage assessment of kimberlites using indicator minerals, petrography andQuebec Exploration Conference, Nov. 25-27, 1p. abstractGlobalMicrodiamonds
DS2003-0836
2003
Grutter, H.Lockhart, G.D., Grutter, H., Carlson, J.A.Temporal and geomagnetic relationship of Ekati's economic kimberlites8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, AbstractNorthwest TerritoriesDiamond exploration - geophysics, magnetics NRM, Deposit - Ekati
DS200412-0113
2003
Grutter, H.Baumgartner, M., Ankar, E., Grutter, H.Compositional classification of kimberlitic and non-kimberlitic ilmenite with implications for visual selection and discriminati8 IKC Program, Session 8, AbstractTechnologyDiamond exploration - mineralogy
DS200412-0387
2003
Grutter, H.Creaser, R.A., Grutter, H., Carlson, J., Crawford, B.Macrocrystal phlogopite Rb Sr dates for the Ekati Province kimberlites, Slave Province, Canada: evidence for multiple intrusive8 IKC Program, Session 7, AbstractCanada, Northwest TerritoriesKimberlite petrogenesis, geochronology
DS200412-0421
2003
Grutter, H.Davis, W.J., Jones, A.G., Bleeker, W., Grutter, H.Lithosphere development in the Slave Craton: a linked crustal and mantle perspective.Lithos, Vol. 71, 2-4, pp. 575-589.Canada, NunavutTectonics
DS200412-0733
2003
Grutter, H.Grutter, H., Gurney, J., Nowicki, T., Moore, R.Early stage assessment of kimberlites using indicator minerals, petrography and microdiamonds.Quebec Exploration Conference, Nov. 25-27, 1p. abstractTechnologyMicrodiamonds
DS200412-1168
2004
Grutter, H.Lockhart, G., Grutter, H., Carlson, J.Temporal, geomagnetic and related attributes of kimberlite magmatism at Ekati, Northwest territories, Canada.Lithos, Vol. 77, 1-4, Sept. pp. 665-682.Canada, Northwest TerritoriesGeomagnetism, geophysics - magnetics, exploration
DS200412-1169
2003
Grutter, H.Lockhart, G.D., Grutter, H., Carlson, J.A.Temporal and geomagnetic relationship of Ekati's economic kimberlites.8 IKC Program, Session 8, AbstractCanada, Northwest TerritoriesDiamond exploration - geophysics, magnetics NRM Deposit - Ekati
DS200412-1298
2004
Grutter, H.Menzies, A., Westerlund, K., Grutter, H., Gurney, J.J., Carlson, J., Fung, A., Nowicki, T.Peridotitic mantle xenoliths from kimberlites on the Ekati diamond mine property, NWT: major element compositions and implicatioLithos, Vol. 77, 1-4, Sept. pp. 395-412.Canada, Northwest TerritoriesSlave Craton, harzburgite, geothermometry, diamond grap
DS200412-1640
2004
Grutter, H.Read, G., Grutter, H., Winter, S., Luckman, N., Gaunt, F., Thomsen, F.Stratigraphic relations, kimberlite emplacement and lithospheric thermal evolution Quirico Basin, Minas Gerais State, Brazil.Lithos, Vol. 77, 1-4, Sept. pp. 803-818.South America, Brazil, Minas GeraisAreado, clinopyroxene, kamafugite, Mata da Corda, therm
DS200412-2151
2004
Grutter, H.Wyatt, B.A., Baumgartner, M., Anckar, E., Grutter, H.Compositional classification of kimberlitic and non-kimberlitic ilmenite.Lithos, Vol. 77, 1-4, Sept. pp. 819-840.TechnologyPicroilmenite, geikielite, hematite, exploration
DS200612-0506
2006
Grutter, H.Grutter, H., Latti, D., Menzies, A.Cr saturation arrays in concentrate garnet compositions from kimberlite and their use in mantle barometry.Journal of Petrology, Vol. 47, 4, April pp. 801-820.MantleGeobarometry, chromite, chromium
DS200712-0200
2007
Grutter, H.Cookenboo, H.O., Grutter, H.Mantle derived indicator mineral compositions as applied to diamond exploration.Proceedings of Exploration 07 edited by B. Milkereit, pp. 183-200.TechnologyGeochemical methods - review
DS200712-0391
2007
Grutter, H.Grutter, H.Application of new age clinopyroxene and garnet thermobarometry techniques in diamond exploration.Diamonds in Kimberley Symposium & Trade Show, Bristow and De Wit held August 23-24, Kimberley, South Africa, GSSA Diamond Workshop CD slides 25TechnologyThermobarometry T, Ni, Mn, garnets
DS200912-0197
2009
Grutter, H.Eaton, D.W., Darbyshire, F., Evans, R.L., Grutter, H., Jones, A.G., Yuan, X.The elusive lithosphere asthenosphere boundary ( LAB) beneath cratons.Lithos, Vol. 109, 1-2, pp. 1-22.MantleBoundary
DS200912-0323
2009
Grutter, H.Hunt, L., Stachel, T., Morton, R., Grutter, H., Creaser, R.A.The Carolin a kimberlite, Brazil - insights into an unconventional diamond deposit.Lithos, In press available 39p.South America, BrazilDeposit - Carolina
DS200912-0537
2009
Grutter, H.Nimis, P., Grutter, H.Internally consistent geothermometers for garnet peridotites and pyroxenites.Contributions to Mineralogy and Petrology, in press available format 17p.TechnologyThermobarometry
DS201012-0543
2010
Grutter, H.Nimis, P., Grutter, H.Internally consistent geothermometers for garnet peridotites and pyroxenites.Contributions to Mineralogy and Petrology, Vol. 159, 3, pp. 411-427. erratum pp. 429-436.TechnologyGeothermometry
DS201012-0544
2010
Grutter, H.Nuber, N., Gerdes, A., Brey, G., Grutter, H.Zircons from kimberlites at Lac de Gras, Canada - a section through the continental crust.International Mineralogical Association meeting August Budapest, abstract p. 561.Canada, Northwest TerritoriesDiamond morphology - size distribution
DS201112-0741
2011
Grutter, H.Nimis, P., Grutter, H.Discussion of 'the applicability of garnet orthopyroxene geobarometry in mantle xenoliths'. Wu and Zhao ( Nimis and Grutter give reasons not)Lithos, in press available 13p.TechnologyGeobarometry
DS201212-0320
2012
Grutter, H.Hunt, L., Stachel, T., Grutter, H., Armstrong, J., McCandless, T.E., Simonetti, A., Tappe, S.Small mantle fragments from the Renard kimberlites, Quebec: powerful recorders of mantle lithosphere formation and modification beneath the eastern Superior Craton.Journal of Petrology, Vol. 53, 8, pp. 1597-1635.Canada, QuebecDeposit - Renard
DS201212-0515
2012
Grutter, H.Neilson, S., Grutter, H., Pell, J., Grenon, H.The evolution of kimberlite indicator mineral interpretation on the Chidliak project, Baffin Island, Nunavut.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, Nunavut, Baffin IslandDeposit - Chidliak
DS201212-0548
2012
Grutter, H.Pell, J., Grutter, H., Grenon, H., Dempsey, S., Neilson, S.Exploration and discovery of the Chidliak kimberlite province, Baffin Island, Nunavut: Canada's newest diamond district.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractCanada, Nunavut, Baffin IslandDeposit - Chidliak
DS201312-0451
2013
Grutter, H.Kamenetsky, V.S., Grutter, H., Kamenetsky, M.B., Gomann, K.Parental carbonatitic melt of the kaola kimberlite ( Canada): constraints from melt inclusions in olivine and Cr-spinel, and groundmass carbonateChemical Geology, Vol. 353, pp. 96-111.Canada, Northwest TerritoriesDeposit - Kaola
DS201312-0695
2013
Grutter, H.Pell, J., Clements, B., Grutter, H., Neilson, S., Grenon, H.Following kimberlite indicator minerals to source in the Chidliak kimberlite province, Nunavut.PDAC 2013 , 6p.Canada, Nunavut, Baffin IslandIndicator Mineralogy
DS201312-0696
2013
Grutter, H.Pell, J., Clements, B., Grutter, H., Neilson, S., Grenon, H.Following kimberlite indicator minerals to source in the Chidliak kimberlite province, Nunavut.GSC Open file 7374 Ftp2.cits.rncan.gc.ca, pp. 47-52.Canada, Nunavut, Baffin IslandDeposit - Chidliak
DS201312-0697
2013
Grutter, H.Pell, J., Grutter, H., Neilson, S.Exploration and discovery of the Chidliak kimberlite province, Baffin Island, Nunavut: Canada's newest diamond district.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, Special Issue of the Journal of the Geological Society of India,, Vol. 2, pp. 209-227.Canada, Nunavut, Baffin IslandDeposit - Chidliak
DS201412-0324
2014
Grutter, H.Grutter, H.Indicator minerals in diamond exploration - an update on contemporary best practises.PDAC 2014, March 3, 1p. AbstractTechnologyGeochemistry
DS201412-0325
2014
Grutter, H.Grutter, H.Banking (on) 10% success - the role of KIMsSRK and Friends Diamond Short Course, March 1, ppt p. 26-33.TechnologyGeochemistry - KIMs
DS201412-0670
2013
Grutter, H.Pell, J., Grutter, H., Neilson, S., Lockhart, G., Dempsey, S., Grenon, H.Exploration and discovery of the Chidliak kimberlite province, Baffin Island, Nunavut: Canada's newest diamond district.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, pp. 209-228.Canada, Nunavut, Baffin IslandDeposit - Chidliak area
DS201605-0840
2016
Grutter, H.Grutter, H.Rapid lithosphere scale events constrained by cpx thermobarometry for the Coromandel area, Brazil.DCO Edmonton Diamond Workshop, June 8-10South America, BrazilCoromandel
DS201611-2130
2016
Grutter, H.Pell, J., Grutter, H.Comments and observations on public-domain micro/macro diamond datasets.Vancouver Kimberlite Cluster, Nov. 8, 1/2p. AbstractTechnologyMicrodiamonds
DS201708-1658
2017
Grutter, H.Grutter, H.Tracing kimberlitic indicators to their kimberlite source at Chidliak, Nunavut, Canada, re-visited: the unexpected accuracy of a simplified Mahalanobis-distance approach.11th. International Kimberlite Conference, OralCanada, Nunavut, Baffin IslandDeposit - Chidliak
DS201708-1659
2017
Grutter, H.Grutter, H.Discrete Al-Ca-Ti metasomatism at 53kbar in chromite+garnet+diamond peridotites from Newlands kimberlite field, South Africa.11th. International Kimberlite Conference, PosterAfrica, South Africadeposit - Newslands
DS201804-0695
2018
Grutter, H.Grutter, H.Pyroxene thermobarometry: a xenocryst - based approach.4th International Diamond School: Diamonds, Geology, Gemology and Exploration Bressanone Italy Jan. 29-Feb. 2nd., pp. 17-18. abstractTechnologythermobarometry
DS201804-0696
2018
Grutter, H.Grutter, H.Microdiamond SFD's and practical use in macrograde forecasting.4th International Diamond School: Diamonds, Geology, Gemology and Exploration Bressanone Italy Jan. 29-Feb. 2nd., pp. 19-20. abstractTechnologymicrodiamonds
DS202112-1928
2021
Grutter, H.Grutter, H.Observations on "Lows" and "Highs" in contemporary  microdiamond data.VCK Talk Nov. 2, https://youtu.be/Be3BNqDZTw0Globalmicrodiamond

Abstract: The evaluation of advanced stage diamond projects is materially constrained by the time and cost involved in bulk sampling (or trial mining) campaigns that serve to demonstrate the grade and value of (macro)diamonds in a deposit. However, comparatively inexpensive assay data for (micro)diamonds may also be used to estimate (macro)diamond grade, by way of geostatistical extrapolation or modelling of total diamond content curves and diamond size frequency distributions. Geoscientists at SRK (Canada) Inc. compiled publicly available technical disclosure related to micro/macrodiamond sampling campaigns completed since early-2004 and developed a model-independent benchmarking approach to estimate in-situ (macro)diamond grades based on microdiamond assay results - a one-page summary of that work is available here: here Our ongoing investigation of microdiamond data has developed a focus on the occurrence of "low-count" and "high-count" microdiamond assay results. In this VKC talk we contrast "normal"-count with "low"-count results (Snap Lake vs FALC and others) and appeal to diamond-bearing mantle xenoliths to explain occasional "high"-count results. Real-world examples are used to cover topics like microdiamond sample sizes and (attained) resolution thresholds in the range 1 part in 1010 to 1012. The talk closes out with an examination of the microdiamond dataset for the Tuwawi pipe (northern Baffin Island).
DS202201-0016
2021
Grutter, H.Grutter, H., Stachel, T., Sarkar, C., Pearson, G.Profound ~ 1075 Ma (re)fertilization of the central Superior craton lithosphere, based on composition and Pb-isotope data for clinopyroxenes from the Victor mine, Ontario, Canada.GAC/MAC Meeting UWO, 1p. Abstract p.117.Canada, Ontariodeposit - Victor

Abstract: The Victor diamond mine in Ontario, Canada opened in 2008 and ceased operations in June 2019. Previous researchers documented that Victor diamonds are unusually young (~ 720 Ma, Aulbach et al., 2018) and grew predominantly in unusually fertile peridotite substrates, specifically garnet lherzolite and garnet wehrlite (Stachel et al., 2018). Our recent work on n=157 lherzolitic clinopyroxene (Cpx) xenocrysts from the Victor mine reveals profound major- and trace-element (re)fertilization of the deepest 1/3rd of the central Superior craton lithosphere. For example, Cpx Mg/(Mg+Fe) of 0.93 in shallow peridotite decreases across a steep gradient to Mg/(Mg+Fe) of 0.89 at depths of 4.2 to 5.6 GPa. We document marked compositional gradients over a similar depth range for certain minor (Ti, Mn, Ni) and trace elements (LREE and HREE) and attribute the gradients to chromatographic and/or crystal-chemical fractionation effects. We carefully categorized the Victor cpx xenocrysts in nine depth-composition classes and determined Pb-isotope ratios for representative grains from each class in a bold experiment aimed at capturing geochronological data from mantle Cpx. A resultant 207Pb/206Pb secondary isochron array at ~ 1075 Ma identifies craton-scale events related to the Mid-Continent Rift as the source of fluids and/or melts that (re)fertilized the central Superior craton at depth, some 355 Ma prior to diamond growth. Coordinated, systematic major- and trace-element relationships in clinopyroxene permit compositional discrimination of mantle (re)fertilization at ~1075 Ma from fluid-metasomatism attending diamond growth at ~ 720 Ma. Roughly 10% of the clinopyroxene xenocrysts analyzed in this work exhibit diamond-associated compositions.
DS202201-0031
2021
Grutter, H.Pearson, G., Schaeffer, A., Stachel, T., Kjarsgaard, B., Grutter, H., Scott, J., Liu, J., Chacko, T., Smit, K.Revisiting the craton concept and its relevance for diamond exploration. *** See also Nature article previously listedGAC/MAC Meeting UWO, 1p. Abstract p. 238. Globalcratons

Abstract: The term craton has a complex and confused etymology. Despite originally specifying only strength and stability - of the crust - the term craton, within the context of diamond exploration, has widely come to refer to a region characterised by crustal basement older than 2.5 Ga, despite the fact that some such “cratons” no longer possess their deep lithospheric root. This definition often precluded regions with deep lithospheric roots but basement younger than 2-2.5 Ga. Viscous, buoyant lithospheric mantle roots are key to the survival and stability of continental crust. Here we use a revised craton definition (Pearson et al., 2021, in press), that includes the requirement of a deep (~150 km or greater) and intact lithospheric root, to re-examine the link between cratons and diamonds. The revised definition has a nominal requirement for tectonic stability since ~ 1 Ga and recognises that some regions are “modified cratons” - having lost their deep roots, i.e., they may have behaved like cratons for an extended period but subsequently lost much of their stabilising mantle roots during major tectono-thermal events. In other words, despite being long-lived features, cratons are not all permanent. The 150 km lithospheric thickness cut-off provides an optimal match to crustal terranes with 1 Ga timescale stability. In terms of regional diamond exploration, for a given area, the crucial criterion is when a deep mantle root was extant, i.e., over what period was the lithospheric geotherm suitable for diamond formation, stability and sampling? A thick lithospheric root is key to the formation of deep-seated magmas such as olivine lamproites and to the evolution of sub-lithospheric sourced proto-kimberlites, all capable of carrying and preserving diamonds to Earth's surface. This criterion appears essential even for sub-lithospheric diamonds, that still require a diamond transport mechanism capable of preserving the high-pressure carbon polymorph via facilitating rapid transport of volatile-charged magma to the surface, without dilution from additional melting that takes place beneath thinner (<120 km) lithospheric "lids". Seismology can help to define the lateral extent of today's cratons, but a detailed understanding of the regional geological history, kimberlite eruption ages and geothermal conditions is required to evaluate periods of past diamond potential, no-longer evident today. This revised craton concept broadens the target terranes for diamond exploration away from only the Archean cores of cratons and an associated mentality that "the exception proves the rule". The revised definition is compatible with numerous occurrences of diamond in Proterozoic terranes or Archean terranes underpinned by Proterozoic mantle.
DS202201-0042
2021
Grutter, H.Stachel, T., Grutter, H.Are peridotitic diamond substrates distinct from diamond-free cratonic peridotites?GAC/MAC Meeting UWO, 1p. Abstract p. 286.Globalperidotites

Abstract: The principal distinction between diamond substrates and the cratonic mantle roots as sampled by garnet peridotite xenoliths is the much higher proportion of harzburgite (-dunite) to lherzolite (-wehrlite) in the former (~85:15 %) compared to the latter (18:82 %). Dunitic mineralogies are common diamond substrates (~38%) but rarely documented in xenoliths (~2 %). Using mineral Mg# as an indicator of source depletion through melt extraction again documents the more depleted character of diamond substrates relative to the cratonic garnet-peridotite xenolith record. On a like-for-like paragenesis level, however, olivine inside and outside of diamond has statistically indistinguishable means in Mg#. This observation implies: (1) that the major element composition of inclusions is imposed largely by the substrate and not by the diamond forming medium and (2) that widespread Fe-rich metasomatism of the lithospheric mantle did not occur subsequent to diamond formation (Paleoarchean to Mesoproterozoic). The latter conclusion precludes neither localized metasomatic shifts in Mg#, nor metasomatism by small melt fractions/fluids subsequent to diamond formation, as such events have low fluid/rock ratios and hence limited impact on bulk rock Mg#. A distinctive feature of inclusions relative to xenolith minerals is the higher Cr/Al of garnet and chromite in diamond. Higher Cr/Al for inclusions is not limited to the harzburgitic-dunitic paragenesis, but also occurs among lherzolitic inclusions. This suggests that the almost exclusive restriction of Cr2O3 contents >13 wt% to inclusion garnets is not a consequence of higher degrees of primary melt depletion being restricted to, or preferentially preserved, in diamond substrates. Instead, the very high Cr contents in a subset of inclusions likely relate to the pressure and temperature dependence of the distribution of Cr between garnet and spinel. Experiments showed inclusion-like high Cr/Al for coexisting Cr-pyrope and Cr-spinel in harzburgite at high pressures and temperatures (>5 GPa and >1200 °C; Girnis and Brey 1999). High Cr/Al inclusion compositions thus likely reflect some diamond growth occurring over a wide range of temperatures, elevated above a cratonic geotherm during high-temperature thermal perturbations. Na and Ti are sensitive indicators of mantle metasomatism. Enrichment of Na and Ti in both inclusion and xenolith minerals is most prominent in the lherzolitic paragenesis and very intense Ti-rich metasomatism is almost entirely restricted to lherzolite xenoliths that resided at temperatures >1130 °C, i.e. above the hydrous solidus. Since equilibration temperatures of >1130 °C are common also for inclusions, the near absence of intense Ti-metasomatism in inclusions likely relates to either a diamond unfriendly character of such metasomatism or an increase in Ti-metasomatic intensity or frequency subsequent to principally Archean-Mesoproterozoic formation of peridotitic diamonds.
DS1988-0275
1988
Grutter, H.S.Grutter, H.S., Robey, J.Lower crustal xenoliths and garnets from Cape Province kimberlitesGeoBulletin, Vol. 31, No. 1, p. 34South AfricaBlank
DS1994-0669
1994
Grutter, H.S.Grutter, H.S.Spinel garnet carbon phase relations in coarse Kaapvaal type peridotite sand implications for equilibration.International Symposium Upper Mantle, Aug. 14-19, 1994, Extended abstracts pp. 5-7.South AfricaMineralogy -garnet, Orthopyroxenite equilibration
DS1998-0541
1998
Grutter, H.S.Grutter, H.S.Chrome - calcium, magnesium number and Yttrium characteristics of garnets in depleted lherzolite...7th International Kimberlite Conference Abstract, pp. 277-9.South Africa, Colorado, ChinaLherzolite, harzburgite, dunite, Mantle xenoliths
DS1998-0542
1998
Grutter, H.S.Grutter, H.S., Apter, D.B.Garnet xenocryst chemistries in a traverse from Eendekuil to Kimberley over the south western margin ..7th International Kimberlite Conference Abstract, pp. 283-6.South AfricaKaapval Craton, Xenolith geochemistry
DS1998-0543
1998
Grutter, H.S.Grutter, H.S., Apter, D.B.Kimberlite and lamproite borne chromite phenocrysts with diamond inclusion type chemistries.7th International Kimberlite Conference Abstract, pp. 280-282.South Africa, BrazilChromite geochemistry, Deposit - Wesselton, Coromandel
DS1998-0544
1998
Grutter, H.S.Grutter, H.S., Quadling, K.E.Some comments on the (ab)use of sodium in garnet to predict eclogitic diamond potential.7th International Kimberlite Conference Abstract, pp. 287-9.South AfricaEclogite - garnets, xenoliths
DS1999-0675
1999
Grutter, H.S.Skinner, E.M.W., Mahotkin, I.L., Grutter, H.S.Melilite in kimberlites7th International Kimberlite Conference Nixon, Vol. 2, pp. 788-94.South Africa, Lesotho, RussiaPetrology - melilite, Deposit - Finsch, Voorspoed, Lace, Swartruggen
DS2000-0365
2000
Grutter, H.S.Grutter, H.S., Sweeney, R.J.Tests and constraints on single grain chromium pyrope barometer models: some initial results.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Calgary May 2000, 4p.GlobalMineral chemistry, chromite, petrology, Diamond stability field
DS2001-0418
2001
Grutter, H.S.Grutter, H.S.The genesis of high chromium/Aluminum garnet peridotite, with implications for cratonic crust: mantle architecture.Slave-Kaapvaal Workshop, Sept. Ottawa, 3p. abstractMantleGeochemistry - peridotite
DS2001-0419
2001
Grutter, H.S.Grutter, H.S.The thermobarometric basis for mantle stratigraphy and mantle mappingProspectors and Developers Association of Canada (PDAC) Short Course, KEGS diamond workshop, 12p.Northwest TerritoriesTheromobarometry, xenoliths, xenocrysts, Geotherms
DS2002-0476
2002
Grutter, H.S.Fowler, J.A., Grutter, H.S., Kong, J.M., Wood, B.D.Diamond exploration in Northern Ontario with reference to the Victor kimberlite, near Attawapiskat.Exploration and Mining Geology, Vol. 10, 1-2, pp. 67-75.OntarioExploration - time lines for mining sequence, Evaluation, program
DS2003-0469
2003
Grutter, H.S.Girnis, A., Grutter, H.S.Thermobarometry of mantle peridotites: calibration based on experimental and natural8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, POSTER abstractGlobalBlank
DS2003-0513
2003
Grutter, H.S.Grutter, H.S., Menzies, A.H.Mutually consistent classification schemes for mantle derived garnet and chromite, for8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, AbstractGlobalDiamond exploration - mineralogy, Mantle phase petrology
DS2003-0514
2003
Grutter, H.S.Grutter, H.S., Moore, R.O.Pyroxene geotherms revisited - an empirical approach based on Canadian xenoliths8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, AbstractNorthwest Territories, Ontario, Somerset IslandMantle petrology, Pyroxene geothermometry
DS2003-1143
2003
Grutter, H.S.Read, G.H., Grutter, H.S., Winter, L.D.S., Luckman, N.B., Gaunt, G.F.M.Stratigraphic relations, kimberlite emplacement and lithospheric thermal evolution8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, AbstractBrazil, Minas GeraisDiamond exploration - thermometry, pipe emplacement
DS200412-0670
2003
Grutter, H.S.Girnis, A., Grutter, H.S.Thermobarometry of mantle peridotites: calibration based on experimental and natural data.8 IKC Program, Session 6, POSTER abstractTechnologyMantle petrology
DS200412-0734
2004
Grutter, H.S.Grutter, H.S., Gurney, J.J., Menzies, A.H., Winter, F.An updated classification scheme for mantle derived garnet, for use by diamond explorers.Lithos, Vol. 77, 1-4, Sept. pp. 841-857.TechnologyExploration, pyrope, Ca intercept, peridotite, megacrys
DS200412-0735
2003
Grutter, H.S.Grutter, H.S., Menzies, A.H.Mutually consistent classification schemes for mantle derived garnet and chromite, for use by diamond explorers.8 IKC Program, Session 8, AbstractTechnologyDiamond exploration - mineralogy Mantle phase petrology
DS200412-0736
2003
Grutter, H.S.Grutter, H.S., Moore, R.O.Pyroxene geotherms revisited - an empirical approach based on Canadian xenoliths.8 IKC Program, Session 6, AbstractCanada, Nunavut, Somerset IslandMantle petrology Pyroxene geothermometry
DS200412-0754
2003
Grutter, H.S.Gurney, J.L., Baumgartner, M., Anckar, E., Gurney, J.J., Nowicki, T.E., Grutter, H.S., Coetzee, M., Mason-JoneKimberlite almanac.8 IKC Program, Session 8, POSTER abstractAfrica, South AfricaDiamond exploration Deposit - Finsch
DS200412-1641
2003
Grutter, H.S.Read, G.H., Grutter, H.S., Winter, L.D.S., Luckman, N.B., Gaunt, G.F.M.Stratigraphic relations, kimberlite emplacement and lithospheric thermal evolution, Quirico Basin, Minas Gerais State, Brazil.8 IKC Program, Session 8, AbstractSouth America, Brazil, Minas GeraisDiamond exploration - thermometry, pipe emplacement
DS200512-0373
2005
Grutter, H.S.Grutter, H.S., Anckar, E.Cr Ca and related characteristics of peridotitic garnets from the central Slave and central Kaapvaal craton roots, with implications - carbon in peridotiteGAC Annual Meeting Halifax May 15-19, Abstract 1p.Canada, Northwest TerritoriesGeochronology, metasomatism
DS200612-0507
2006
Grutter, H.S.Grutter, H.S.Cr pyrope and chromite inside and outside diamond: a tribute to the work of Jeff Harris.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 219. abstract only.TechnologyMineral chemistry
DS200912-0271
2009
Grutter, H.S.Grutter, H.S., Tuer, J.Constraints on deep mantle tenor of Sarfatyoq area kimberlites ( Greenland) based on modern thermobarometry of mantle derived xenocrysts.Lithos, in press availableEurope, GreenlandGeothermometry
DS200912-0638
2009
Grutter, H.S.Rogers, A.J., Grutter, H.S.Fe rich and Na rich megacryst clinopyroxene and garnet from the Luxinga kimberlite cluster, Lunda Sul, Angola.Lithos, In press - available 30p.Africa, AngolaDeposit - Luxinga
DS201012-0119
2010
Grutter, H.S.Cookenboo, H.O., Grutter, H.S.Mantle derived indicator mineral compositions as applied to diamond exploration.Geochemistry, Exploration, Environment, Analysis, Vol. 10, no. 1, pp. 81-95.TechnologyOverview of mineral chemistry - Kaapvaal, Slave Cratons
DS201012-0253
2009
Grutter, H.S.Grutter, H.S.Pyroxene xenocryst geotherms: techniques and application.Lithos, Vol. 112 S pp. 1167-1178.Canada, Northwest TerritoriesThermobarometry
DS201012-0731
2010
Grutter, H.S.Snyder, D.B., Grutter, H.S.Lithoprobes impact on the Canadian diamond exploration industry.Canadian Journal of Earth Sciences, Vol. 47, 5, pp. 783-800.CanadaGeophysics
DS201212-0265
2012
Grutter, H.S.Grutter, H.S., Gerdes, A., Marko, L., Heaman, L.M.U-Pb geochronology of perovskite and zircon from the Chigicherla kimberlites, Anatapur district, India.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractIndiaDeposit - Chigicherla
DS201212-0295
2012
Grutter, H.S.Herman, L.M., Grutter, H.S., Pell, J., Holmes, P., Grenon, H.U-Pb geochronology , SR and ND isotope compositions of groundmass perovskite from the Chidliak and Qilaq kimberlites, Baffin Island, Nunavut.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, Nunavut, Baffin IslandDeposit - Chidliak, Qilaq
DS201504-0201
2015
Grutter, H.S.Heaman, L.M., Pell, J., Grutter, H.S., Creaser, R.A.U-Pb geochronology and Sr/Nd isotope compositions of groundmass perovskite from the newly discovered Jurassic Chidliak kimberlite field, Baffin Island, Canada.Earth and Planetary Science Letters, Vol. 415, April pp. 183-189.Canada, Nunavut, Baffin IslandDeposit - Chidliak
DS201807-1496
2018
Grutter, H.S.Grutter, H.S., Pell, J.A., Fitzgerald, C.E.Use of a simplified Mahalanobis distance approach to constrain the dispersion and provenance of Cr-pyrope populations at the Chidliak kimberlite province, Nunavut, Canada.Mineralogy and Petrology, June 14, DOI:10.1007/ s0710-018 -0578-7, 12p.Canada, Nunavutdeposit - Chidliak

Abstract: Exploration for diamond-bearing kimberlites in the Chidliak project area by Peregrine Diamonds has generated a grid-like till sampling pattern across four discrete areas of interest totalling 402 km2 that is densely populated with research-grade compositional data for 10,743 mantle-derived Cr-pyrope garnets. The available dataset is well suited to statistical analysis, in part due to the relatively unbiased spatial coverage. Previous workers showed empirically that the TiO2 and Mn thermometry (Ti-TMn) attributes of Cr-pyrope populations at the Chidliak project may serve as source-specific “fingerprints”. In this work, we employ a simplified version of the multivariate Mahalanobis distance technique to formally examine the variability of, and differences between, Ti-TMn attributes of Cr-pyrope subpopulations recovered from a Laurentide-age glaciated terrain that also contains 30 known kimberlites within the four areas of interest. We show the simplified Mahalanobis distance approach enables accurate discrimination of Cr-pyrope subpopulations with subtly to distinctly different Ti-TMn attributes, and permits proper demarcation of their respective kimberlite source(s), specifically in areas with straightforward glacial histories. Redistribution and blending of Cr-pyrope subpopulations from known kimberlite sources is also observed, and typifies areas at Chidliak with complex late-glacial histories. Our results support <1 km horizontal scale subtle to obvious variability in the proportions of TiO2-rich and high-temperature (> 1100 °C) Cr-pyropes between closely spaced kimberlite source(s) and also between physically adjacent magma batches within single kimberlite pipes. The local scale variability is attributed to protokimberlite fluid or melt interacting with, and metasomatizing discrete conduits within, the ambient diamond-facies peridotitic mantle at times closely preceding eruption of kimberlite magma batches at Chidliak.
DS201610-1845
2016
Grutzner, T.Beyer, C., Klemme, S., Grutzner, T., Ireland, T.R., Magee, C.W., Frost, D.J.Fluorine partitioning between eclogitic garnet, clinopyroxene, and melt at upper mantle conditions.Chemical Geology, Vol. 437, pp. 88-97.MantleLamproite

Abstract: In this experimental study we obtained new mineral/melt (DF = cmineral/cmelt) partitioning data for fluorine in a bimineralic hydrous eclogite under Earth's upper mantle conditions (4-6 GPa, 1460-1550 °C). Omphacitic clinopyroxene displays mineral/melt partition coefficients between DF = 0.056 ± 0.005 and DF = 0.074 ± 0.001. Garnet partition coefficients are consistently lower with an average partition coefficient of DF = 0.016 ± 0.003. We found that omphacitic clinopyroxene is the dominant nominally fluorine-free phase in subducted oceanic crust and hence omphacite is expected to be the major fluorine carrier during subduction of crust into the deeper mantle. Together with previously obtained partitioning data we propose that the oceanic crust can host more fluorine per mass unit than the underlying depleted oceanic mantle. If the majority of entrained fluorine is recycled into Earth's transition zone it is possible that the fluorine is either incorporated into high-pressure transition zone phases or released during high-pressure phase transformations and forming fluorine-rich small degree partial melts. Both scenarios are supported by elevated fluorine concentration in ocean island basalts, kimberlites, and lamproites. Combining the fluorine partitioning data with water partitioning data yields a plausible process to generate lamproitic magmas with a high F/H2O ratio. The enrichment of fluorine relative to H2O is triggered by multiple episodes of small degree melting that deplete the residual more in H2O than in fluorine, caused by the approximately three times smaller mineral-melt partition coefficients of H2O.
DS201705-0829
2017
Grutzner, T.Gervasoni, F., Klemme, S., Rohrbach, A., Grutzner, T., Berndt, J.Experimental constraints on mantle metasomatism caused by silicate and carbonate melt.Lithos, Vol. 282-283, pp. 173-186.MantleCarbonatite

Abstract: Metasomatic processes are responsible for many of the heterogeneities found in the upper mantle. To better understand the metasomatism in the lithospheric mantle and to illustrate the differences between metasomatism caused by hydrous silicate and carbonate-rich melts, we performed various interaction experiments: (1) Reactions between hydrous eclogite-derived melts and peridotite at 2.2-2.5 GPa and 900-1000 °C reproduce the metasomatism in the mantle wedge above subduction zones. (2) Reactions between carbonate-rich melts and peridotite at 2.5 GPa and 1050-1000 °C, and at 6 GPa and 1200-1250 °C simulate metasomatism of carbonatite and ultramafic silicate-carbonate melts in different regions of cratonic lithosphere. Our experimental results show that partial melting of hydrous eclogite produces hydrous Si- and Al-rich melts that react with peridotite and form bi-mineralic assemblages of Al-rich orthopyroxene and Mg-rich amphibole. We also found that carbonate-rich melts with different compositions react with peridotite and form new metasomatic wehrlitic mineral assemblages. Metasomatic reactions caused by Ca-rich carbonatite melt consume the primary peridotite and produce large amounts of metasomatic clinopyroxene; on the other hand, metasomatism caused by ultramafic silicate-carbonate melts produces less clinopyroxene. Furthermore, our experiments show that ultramafic silicate-carbonate melts react strongly with peridotite and cause crystallization of large amounts of metasomatic Fe-Ti oxides. The reactions of metasomatic melts with peridotite also change the melt composition. For instance, if the carbonatite melt is not entirely consumed during the metasomatic reactions, its melt composition may change dramatically, generating an alkali-rich carbonated silicate melt that is similar in composition to type I kimberlites.
DS201706-1072
2017
Grutzner, T.Gervasoni, F., Klemme, S., Rohrbach, A., Grutzner, T., Berndt, J.Experimental constraints on the stability of baddeleyite and zircon in carbonate and silicate carbonate melts.American Mineralogist, Vol. 102, pp. 860-866.carbonatite

Abstract: Carbonatites are rare igneous carbonate-rich rocks. Most carbonatites contain a large number of accessory oxide, sulfide, and silicate minerals. Baddeleyite (ZrO2) and zircon (ZrSiO4) are common accessory minerals in carbonatites and because these minerals host high concentrations of U and Th, they are often used to determine the ages of formation of the carbonatite. In an experimental study, we constrain the stability fields of baddeleyite and zircon in Ca-rich carbonate melts with different silica concentrations. Our results show that SiO2-free and low silica carbonate melts crystallize baddeleyite, whereas zircon only crystallizes in melts with higher concentration of SiO2. We also find that the zirconsilicate baghdadite (Ca3ZrSi2O9) crystallizes in intermediate compositions. Our experiments indicate that zircon may not be a primary mineral in a low-silica carbonatite melt and care must be taken when interpreting zircon ages from low-silica carbonatite rocks.
DS201804-0697
2018
Grutzner, T.Grutzner, T., Klemme, S., Rohrbach, A., Gerbasoni, F., Berndt, J.The effect of fluorine on the stability of wadsleyite: implications for the nature and depths of the transition zone in the Earth's mantle.Earth and Planteray Science Letters, Vol. 482, pp. 236-244.Mantletransition zone

Abstract: The Earth's mantle contains significant amounts of volatile elements, such as hydrogen (H), carbon (C) and the halogens fluorine (F), chlorine (Cl) and bromine (Br) and iodine (I). There is a wealth of knowledge about the global cycling of H and C, but there is only scant data on the concentrations of halogens in different Earth reservoirs and on the behavior of halogens during recycling in subduction zones. Here we focus on the storage potential of F in deeper parts of the Earth's mantle. The transition zone is a region in the Earth's mantle (410-660 km) known for its high water storage capacity, as the high pressure polymorphs of olivine, wadsleyite and ringwoodite are known to be able to incorporate several per-cent of water. In order to assess potential fractionation between water and F in the transition zone of the Earth's mantle, we set out to investigate the storage capacity of the halogen F in wadsleyite and olivine at transition zone conditions. Experiments were performed in a simplified mantle composition at temperatures from 1400?°C to 1900?°C and pressures from 17 up to 21 GPa in a multi anvil apparatus. The results show that F can shift the olivine-wadsleyite transition towards higher pressure. We find that F has an opposing effect to water, the latter of which extends the transition zone towards lower pressure. Moreover, the F storage capacity of wadsleyite is significantly lower than previously anticipated. F concentrations in wadsleyite range from to independent of temperature or pressure. The F storage capacity in wadsleyite is even lower than the F storage capacity of forsterite under transition zone conditions, and the latter can incorporate F under these conditions. Based on our data we find that the transition zone cannot be a reservoir for F as it is assumed to be for water. Furthermore, we argue that during subduction of a volatile-bearing slab, fractionation of water from F will occur, where water enters preferentially the transition zone and F remains in the peridotite of the lowermost upper mantle.
DS201906-1279
2019
Grutzner, T.Bussweiler, Y., Grutzner, T., Rohrbach, A., Klenne, S.New insights into cratonic mantle metasomatism from HP-HT reaction experiments between saline fluids and mantle rocks.GAC/MAC annual Meeting, 1p. Abstract p. 67.Mantlemetasomatism

Abstract: Saline (Cl-rich) fluids potentially play an important role as metasomatic agents in the lithospheric mantle. Natural evidence for deep saline fluids exists as inclusions within diamonds and within groundmass minerals in kimberlites. Previous experimental studies have investigated melting relations in the chloride-carbonate-silicate system at upper mantle conditions, but a systematic experimental study of how saline fluids react with the lithospheric mantle is still lacking. Here, we present high-pressure, high-temperature (HP-HT) reaction experiments between a saline fluid and different mantle rocks (lherzolite, harzburgite, eclogite) at conditions corresponding to the lower cratonic lithosphere. Experiments were performed over a P-T range of 3-6 GPa and 1050-1300 °C using a multi-anvil apparatus. Preliminary results show that the interaction between saline fluid and mantle rocks is very reactive, compared to reactions with silico-carbonate melts. The reaction between saline fluid and lherzolite at 4 GPa and 1200 °C leads to extensive melting. The restite consists mainly of olivine and garnet, whereas pyroxenes are only observed as rare inclusions within garnet. In contrast, reactions between saline fluid and eclogite at 4 GPa and 1200 °C also lead to melting, but the melt is more enriched in Si. The restite consists exclusively of garnet. The experimental results demonstrate how saline fluids react with different components of the lithospheric mantle and support evolutionary models of high density fluids within diamonds.
DS202112-1951
2021
Gryaznov, I.Sonin, V., Zhimulev, E., Chepurov, A., Gryaznov, I., Chepurov, A., Afanasiev, V., Poikilenko, N.Experimental etching of diamonds: extrapolation to impact diamonds from the Popigai Crater ( Russia)MDPI, Vol. 11, 11p. Pdf Russiadeposit - Popigai

Abstract: Diamond etching in high-temperature ambient-pressure experiments has been performed aimed to assess possible postimpact effects on diamonds in impact craters, for the case of the Popigai crater in Yakutia (Russia). The experiments with different etchants, including various combinations of silicate melts, air, and inert gases, demonstrated the diversity of microstructures on {111} diamond faces: negative or positive trigons, as well as hexagonal, round, or irregularly shaped etch pits and striation. The surface features obtained after etching experiments with kimberlitic diamonds are similar to those observed on natural impact diamonds with some difference due to the origin of the latter as a result of a martensitic transformation of graphite in target rocks. Extrapolated to natural impact diamonds, the experimental results lead to several inferences: (1) Diamond crystals experienced natural oxidation and surface graphitization during the pressure decrease after the impact event, while the molten target rocks remained at high temperatures. (2) Natural etching of diamonds in silicate melts is possible in a large range of oxidation states controlled by O2 diffusion. (3) Impact diamonds near the surface of molten target rocks oxidized at the highest rates, whereas those within the melt were shielded from the oxidizing agents and remained unchanged.
DS202005-0735
2020
Gryaznov, I.A.Gryaznov, I.A., Zhimulev, E.I., Sonin, V.M., Lindenblot, E.S., Chepurov, A.A.Morphological features of diamond crystals resulting from dissolution in a Fe-Ni-S melt under high pressure.Doklady Earth Sciences, Vol. 489, 2, pp. 1449-1452 .pdfRussiadiamond morphology, CLIPPIR

Abstract: The primary results are presented on the dissolution of plane-faced diamond crystals of octahedral habit in a Fe-Ni-S melt under 3.5 GPa and 1400°C. It was found that the dissolution resulted in the transformation of plane-faced into curve-faced individuals of morphological features characteristic for kimberlite diamonds. It was concluded that the diamond forms as such might have formed in reduced domains of the Earth’s mantle before becoming involved in the kimberlite magma.
DS202107-1135
2021
Gryaznov, I.A.Sonin, V.M., Gryaznov, I.A., Chepurov, A. I., Pokhilenko, N.P.H2O as a possible initiator of surface graphitization of impact diamonds.Doklady Earth Sciences, Vol. 498, 1, pp. 388-391.Russiadiamond crystallography
DS1991-1362
1991
GryaznovaPokrovskiy, B.G., Belyakov, A.Yu., Kravchenko, S.M., GryaznovaIsotope dat a on the origin of carbonatites and mineralized strat a in the Tomtor intrusion, northwest YakutiaGeochemistry International, Vol. 28, No. 4, pp. 93-101RussiaCarbonatite, Geochronology
DS1993-1142
1993
Grybeck, D.Nokleberg, W.J., Bundtzen, T.K., Grybeck, D., Koch, R.D., EreminMetallogenesis of maIn land Alaska and the Russian northeastUnited States Geological Survey (USGS) Open file, No. 93-339, approx. $ 48.00Alaska, RussiaBook -table of contents, Metallogeny, alluvials, placers, lode, chromite, gold, platinum group elements (PGE)
DS201608-1411
2015
Grynberg, R.Grynberg, R., Mbayi, L.The Global diamond industry: economics and Development. Vol. I and IIPalgrave Hamilton, Hampshire (Publishers), Two separate Vols. Each $ 75.00 Kindle editionGlobalBook - diamond industry
DS2002-0619
2002
GSA TodayGSA TodayPenrose conference scheduled... Precambrian high pressure high temperature metamorphism.. key to plate..Gsa Today, April p. 43.ChinaNews item - UHP
DS2002-0620
2002
GSA TodayGSA TodayStructure and evolution of lithosphere beneath the Rocky Mountains: initial results from CD-ROM experimentGsa Today, Vol. 12,3,Marchpp. 4-10.Wyoming, ColoradoTectonics, State Line
DS201212-0266
2012
GSFAGSFADiamond in the rough: half century puzzle solved. Cold compressed graphiteGFSA Newsletter, 1/2p. Excerpt from NatureTechnologyCarbon
DS200512-1211
2005
Gspann, J.Yamaguchi, Y., Gspann, J.MD study on high energy reactive carbon and oxygen cluster impact leading to surface erosion on diamond.Nuclear Instruments and Methods in Physics Research Section B., Vol. 228, 1-4, pp. 309-314.Diamond morphology
DS201809-2103
2018
Gtreenberg, E.Tschauner, O., Huang, S., Wu, Z., Gtreenberg, E., Prakapenka, V.B.Ice-VII inclusions in ultradeep diamonds. Goldschmidt Conference, 1p. AbstractAfrica, South Africa, China, United States, Canada, South Americadiamond inclusions

Abstract: We present the first evidence for inclusions of ice-VII in diamonds from southern Africa, China, North- and South-America [1]. Combining synchrotron X-ray diffraction, - X-ray fluorescence and IR spectroscopy, we show the presence of ice-VII as inclusions in diamonds that have formed at depth > 410 km to about 800 km in the Earth's mantle. What is now crystalline ice-VII, a high pressure polymorph of water-ice, was component of an aqueous fluid entrapped in the diamonds that were growing in the deep mantle. Because of the confinement by the host diamonds, the inclusions retain high pressures. The same holds for inclusions of magnesian calcite, halite, and ilmenite found in the same diamond specimens. These inclusions reflect the presence of aqueous and carbonaceous fluids in the mantle transition zone and the shallow lower mantle. Using their current residual pressures and the equations of state, we can reconstruct their recovery paths [2,3]. Further, we can use the intersection of modelled recovery paths to better constrain the encapsulation pressure and temperature of these inclusions in diamonds.
DS202001-0047
2020
Gu, H.Wang, X., Xiao, Y., Sun, Y., Wang, Y., Liu, J., Yang, K., Gu, H., Hou, Z., Tian, Y., Wu, W., Ma, Y.Initiation of the North China craton destruction: constraints from the diamond bearing alkaline basalts from Langan, China.Gondwana Research, Vol. 80, pp. 228-243.Chinacraton

Abstract: The North China Craton (NCC) is an atypical ancient landmass that suffered lithospheric destruction. Previous studies suggest that the eastern part of the lithospheric mantle of the NCC has been thinned and modified in the Mesozoic. However, the initiation time and mechanism of the destruction remain controversial. Mafic magmatismcould provide a unique windowinto deciphering the lithospheric mantle composition and its evolution. Here we present geochemical and geochronological data of the diamond-bearing alkaline basalts from Lan'gan, located in the southeastern margin of the NCC. Zircon U-Pb dating yielded an average age of 174 ± 14 Ma, representing the first reported Jurassic basalts in the eastern NCC. The Lan'gan basalts are enriched in light rare earth elements (LREE) and large ion lithosphile elements (LILE). Sr-Nd-Pb-Hf isotopic compositions (87Sr/86Sr(t) = 0.70646-0.70925, ?Nd(t) = ?2.1 to ?4.9, 206Pb/204Pb(t) = 17.14-18.12, 207Pb/204Pb(t) = 15.28-15.61, 208Pb/204Pb(t) = 37.82-38.67, and zircon ?Hf(t) = ?17 to ?21) are enriched compared to depleted mantle. The presence of primary amphibole indicates that the magma source of the basalts was water enriched. These observations suggest that, the lithospheric mantle of the eastern NCC were significantly refertilized, likely by slab derived fluids/melts fromthe Paleo-Pacific subduction. Owing to the Paleo-Pacific subduction, the lithosphericmantle of the eastern NCCwere reduced in viscosity and intensity, and finally promoted partialmelting in a limited scale to generate the investigated alkaline basalts. Hence, the discovery of diamond in the Lan'gan basalts demonstrates that the lithosphere of the NCC remained thick, and that large-scale destruction had not initiated in the early Jurassic beneath this region.
DS202004-0542
2020
Gu, H.Wang, X., Xiao, Y., Wang, Y., Liu, J., Yang, K., Gu, H., Hou, Z., Tian, Y., Wu, W., Ma, Y.Initiation of the North China Craton destruction: constraints from the diamond bearing alkaline basalts from Langan China.Gondwana Research, Vol. 80, pp. 228-243.Chinadeposit - Langan

Abstract: The North China Craton (NCC) is an atypical ancient landmass that suffered lithospheric destruction. Previous studies suggest that the eastern part of the lithospheric mantle of the NCC has been thinned and refertilized in the Mesozoic. However, the initiation time and mechanism of the destruction remain controversial. Mafic magmatism could provide a unique window into deciphering the lithospheric mantle composition and its evolution. Here we present geochemical and geochronological data of the diamond-bearing alkaline basalts from Lan'gan, located in the southeastern margin of the NCC. Zircon UPb dating yielded an average age of 174?±?14?Ma, representing the first reported Jurassic basalts in the eastern NCC. The Lan'gan basalts are enriched in light rare earth elements (LREE) and large ion lithosphile elements (LILE). Sr-Nd-Pb-Hf isotopic compositions (87Sr/86Sr(t)?=?0.70646-0.70925, ?Nd(t)?=??2.1 to ?4.9, 206Pb/204Pb(t)?=?17.14-18.12, 207Pb/204Pb(t)?=?15.28-15.61, 208Pb/204Pb(t)?=?37.82-38.67, and zircon ?Hf(t)?=??17 to ?21) are slightly enriched compared to depleted mantle. The presence of primary amphibole indicates that the magma source of the basalts was water enriched. These observations suggest that, the lithospheric mantle of the eastern NCC were significantly refertilized, likely by slab derived fluids/melts from the Paleo-Pacific subduction. Owing to the Paleo-Pacific subduction, the lithospheric mantle of the eastern NCC were reduced in viscosity and intensity, and finally promoted partial melting in a limited scale to generate the investigated alkaline basalts. Hence, the discovery of diamond in the Lan'gan basalts demonstrates that the lithosphere of the NCC remained thick, and that large-scale destruction had not initiated in the early Jurassic beneath this region.
DS201607-1306
2016
Gu, H-O.Li, W-Y., Teng, F-Z., Xiao, Y., Gu, H-O., Zha, X-P.Empirical calibration of the clinopyroene-garnet magnesium isotope geothermometer and implications. DabieContributions to Mineralogy and Petrology, Vol. 171, 7, 14p.ChinaGeothermometry

Abstract: The large equilibrium Mg isotope fractionation between clinopyroxene and garnet observed in eclogites makes it a potential high-precision geothermometer, but calibration of this thermometer by natural samples is still limited. Here, we report Mg isotopic compositions of eclogite whole rocks as well as Mg and O isotopic compositions of clinopyroxene and garnet separates from 16 eclogites that formed at different temperatures from the Dabie orogen, China. The whole-rock ?26Mg values vary from ?1.20 to +0.10 ‰. Among them, 11 samples display limited ?26Mg variations from ?0.36 to ?0.17 ‰, similar to those of their protoliths. The mineral separates exhibit very different ?26Mg values, from ?0.39 to +0.39 ‰ for clinopyroxenes and from ?1.94 to ?0.81 ‰ for garnets. The clinopyroxene -garnet Mg isotope fractionation (?26Mgclinopyroxene -garnet = ?26Mgclinopyroxene -?26Mggarnet) varies from 1.05 to 2.15 ‰. The clinopyroxene -garnet O isotope fractionation (?18Oclinopyroxene -garnet = ?18Oclinopyroxene -?18Ogarnet) varies from ?1.01 to +0.98 ‰. Equilibrium Mg isotope fractionation between clinopyroxene and garnet in the investigated samples is selected based on both the ?26Mgclinopyroxene versus ?26Mggarnet plot and the state of O isotope equilibrium between clinopyroxene and garnet. The equilibrium ?26Mgclinopyroxene -garnet and corresponding temperature data obtained in this study, together with those available so far in literatures for natural eclogites, are used to calibrate the clinopyroxene -garnet Mg isotope thermometer. This yields a function of ?26Mgclinopyroxene -garnet = (0.99 ± 0.06) × 106/T 2, where T is temperature in Kelvin. The refined function not only provides the best empirically calibrated clinopyroxene -garnet Mg isotope thermometer for precise constraints of temperatures of clinopyroxene- and garnet-bearing rocks, but also has potential applications in high-temperature Mg isotope geochemistry.
DS201708-1660
2017
Gu, T.Gu, T.1aB diamond and its geological implications.11th. International Kimberlite Conference, PosterAfrica, Botswanadeposit - Karowe
DS201811-2574
2018
Gu, T.Gu, T., Wang, W.Optical defects in milky type I aB diamonds.Diamond & Related Materials, Vol. 89, pp. 322-329.Russia, Indiadeposit - Mir, Panna

Abstract: The optical features of milky type IaB diamonds were studied systematically by non-destructive approaches including FTIR, photoluminescence (PL), and cathodoluminescence (CL) spectroscopy. From 97 type IaB diamonds ranging from 0.2?ct to ~100?ct submitted to GIA's New York laboratory for screening, we found that all the milky type IaB diamonds consistently displayed the hydrogen-related defect with an absorption line at 3107?cm?1, and ~96% of them were accompanied by a weaker line at 3085.4?cm?1, which is undetectable in most non-milky diamonds. Most of the diamond samples display no platelet defect or a very tiny residual platelet peak with a position at larger wavenumber in milky diamonds than in non-milky counterparts. “Amber center” with a weak but sharp absorption line at 4168.8?cm?1 has been observed in ~73% of the milky diamonds and ~24% of the non-milky ones. Photoluminescence (PL) results reveal that several defects with ZPLs at 490.7, 536, 575.9 and 612.4?nm are more common in milky type IaB diamonds than non-milky ones. A zero-phonon line (ZPL) at 536?nm has been confirmed by PL mapping and CL spectra as a product of plastic deformation, and it might be linked with the H4 center (N4V2 defect). A ZPL at 490.7?nm could be related to a nitrogen-vacancy complex. The defects present more often in milky IaB diamonds are generally associated with plastic deformation. The presence of a hydrogen-related peak at 3085.4?cm?1 and a 536?nm center would help effectively distinguish IaB diamonds with subtle milky areas from their non-milky counterparts.
DS201812-2814
2018
Gu, T.Gu, T., Wang, W.Optical defects in milky type IaB diamonds.Diamond & Related Materials, Vol. 89, pp. 322-329.Russia, India, South America, Brazilphotoluminesence spectroscopy
DS201901-0039
2018
Gu, T.Gu, T., Valley, J., Kitajima, K., Spicuzza, M., Fournelle, J., Stern, R., Ohfuji, H., Wang, W.Evidence of subducted altered oceanic crust into deep mantle from inclusions of type IaB diamonds,Gems & Gemology, Sixth International Gemological Symposium Vol. 54, 3, 1p. Abstract p. 306-7.Mantlediamond inclusions

Abstract: Nitrogen is one of the most common impurities in diamond, and its aggregation styles have been used as criteria for diamond classification. Pure type IaB diamonds (with 100% nitrogen in B aggregation) are rather rare among natural diamonds. The occurrence of the B center is generally associated with high temperature and a long residence time of the host diamond, which would potentially provide information on the earth’s deep interior. Seawater circulation is the unique process that shapes the surface of our planet and potentially has a profound effect on its interior due to slab subduction. In about 50 type IaB diamonds with detectable micro-inclusions submitted to GIA for screening, we found that more than 70% of them contained a typical mineral assemblage from the sublithosphere. Jeffbenite (TAPP), majorite garnet, enstatite, and ferropericlase have been observed, which could be retrograde products of former bridgmanite. CaSiO3-walstromite with larnite and titanite is the dominant phase present in approximately 40% of all diamond samples. Direct evidence from oxygen isotope ratios measured by secondary ion mass spectrometry, or SIMS, (?18OVSMOWin the range +10.7 to +12.5‰) of CaSiO3-walstromite with coexisting larnite and titanite that retrograde from CaSiO3-perovskite suggest that hydrothermally altered oceanic basalt can subduct to depths of >410 km in the transition zone. Incorporation of materials from subducted altered oceanic crust into the deep mantle produced diamond inclusions that have both lower mantle and subduction signatures. Ca(Si,Al)O3-perovskite was observed with a high concentration of rare earth elements (>5 wt.%) that could be enriched under P-Tconditions in the lower mantle. Evidence from ringwoodite with a hydroxide bond, coexisting tuite and apatite, precipitates of an NH3phase, and cohenite with trace amounts of Cl imply that the subducted brines can potentially introduce hydrous fluid to the bottom of the transition zone. In the diamonds with subducted materials, the increasing carbon isotope ratio from the core to the rim region detected by SIMS (?13C from -5.5‰ to -4‰) suggests that an oxidized carbonate-dominated fluid was associated with recycling of the subducted hydrous material. The deep subduction played an important role in balancing redox exchange with the reduced lower mantle indicated by precipitated iron nanoparticles and coexisting hydrocarbons and carbonate phases.
DS201906-1297
2019
Gu, T.Gu, T., Ohfuji, H., Wang, W.Origin of milky optical features in type 1aB diamonds: dislocations, nano-inclusions, and polycrystalline diamond.American Mineralogist, Vol. 104, pp. 652-658.Globaldiamond morphology
DS201802-0240
2018
Gu, X.Gu, X., Ingrin, J., Deloule, E., France, L., Xia, Q.Metasomatism in the sub-continental lithospheric mantle beneath the south French Massif Central: constraints from trace elements, Li and H in peridotite minerals.Chemical Geology, Vol. 478, pp. 2-17.Europe, Franceperidotite

Abstract: Mantle metasomatism by percolating melts/fluids can significantly modify the geochemical and mineralogical compositions of the sub-continental lithospheric mantle (SCLM). We present a detailed study of water contents and Li concentrations and isotopic compositions in mantle minerals from a suite of peridotite xenoliths entrained by a Cenozoic Strombolian volcano in the southern French Massif Central (FMC). Wide ranging clinopyroxene trace element distributions (e.g., (La/Yb)N from 0.25 to 22.21; Ti/Eu ratios from 453 to 4892) suggest that the SCLM has undergone metasomatism by carbonatitic melts/fluids or melts/fluids related to subducted materials. Two amphibole-bearing samples exhibit depletion of light rare earth elements (LREE; (La/Yb)N = 0.26 and 0.30, respectively) in amphiboles, similar to that in co-existing clinopyroxenes; these samples indicate that amphiboles grew during a separate modally metasomatic event predating the cryptic metasomatism accounting for LREE enrichment and negative HFSE anomalies in other samples. Mineral Li concentrations are similar to those in the normal mantle, with inter-mineral Li partitioning nearly equilibrated and intragranular Li distributions nearly homogeneous. However, negative ?7Li values of pyroxenes in some samples (as low as ? 8.8‰ in clinopyroxene of sample MC38) can be attributed to diffusive exchange with a small-volume melt of moderate Li concentration and light Li isotopic composition, originally associated with a recycled component. Preservation of the currently observed large inter-mineral Li isotopic variations indicates that melt percolation occurred shortly before entrainment of the peridotite xenoliths by the host magma. Mineral water contents vary from 41 to 428 ppm in clinopyroxenes and from 28 to 152 ppm in orthopyroxenes, and their roughly negative co-variation with coexisting olivine Fo contents imply that partial melting was the main control over mineral water content variations in most samples. Varied water contents in LREE-enriched metasomatized samples indicate the involvement of metasomatic agents of different origins. The aqueous agent responsible for generation of amphiboles in two samples did not produce a notable increase in the water contents of coexisting nominally anhydrous minerals.
DS201112-0613
2011
Gu, X-F.Liu, Y-C., Gu, X-F., Rolfo, F., Chen, Z-Y.Ultra high pressure metamorphism and multistage exhumation of eclogite of the Luotian dome, North Dabie Complex Zone: evidence from mineral inclusions -textureJournal of Asian Earth Sciences, Vol. 42, 4, pp. 607-617.Asia, ChinaUHP
DS201412-0521
2014
Gu, X-F.Liu, Y-C., Deng, L-P., Gu, X-F., Groppo, C., Rolfo, F.Application of Ti in zircon and Zr in rutile thermometers to constrain high temperature metamorphism in eclogites from the Dabie Orogen, central China.Gondwana Research, Vol. 27, pp. 410-423.ChinaEclogite
DS202009-1623
2019
Gu, X-F.Deng, L-P., Liu, Y-C., Yang, Y., Groppo, C., Rolfo, F., Gu, X-F.Anatexis of high-T eclogites in the Dabie orogen triggered by exhumation and post-orogenic collapse.European Journal of Mineralogy, Vol. 31, pp. 889-803. pdfChinaeclogite

Abstract: A combined study of detailed petrographic observation, mineral chemistry analysis and phase equilibrium modeling indicates that the high-temperature eclogites from the Dabie orogen, central China, experienced two episodes of anatexis: the first is phengite dehydration melting during the exhumation of deeply subducted slices, and the second is heating melting related to the post-orogenic collapse. Petrographic evidence and clues of the anatectic events include biotite + plagioclase + garnet ± amphibole intergrowth in matrix and biotite + plagioclase intergrowth within amphibole porphyroblast. Pressure-temperature (P-T) pseudosection and modal variation diagram indicate that the biotite + plagioclase + garnet ± amphibole in matrix was formed by the reactions phengite + clinopyroxene + quartz = melt + sanidine + garnet + plagioclase and later melt + sanidine + garnet = biotite + plagioclase, while the biotite + plagioclase intergrowths within poikiloblastic amphibole were formed by the reaction amphibole + muscovite + epidote = biotite + plagioclase + melt. In addition, the combination of petrological observations and P-T estimates suggests that the first melting event occurred at the late Triassic, while the second is related to the early Cretaceous mountain-root removal and subsequent asthenospheric upwelling and heat input. As the P-T paths of high-temperature/ultrahigh-pressure rocks have high probabilities to cross-cut phengite-melting curves, phengite melting during decompression may be a common process in these rocks. Moreover, the coexistence of multiple episodes of anatexis in a single tectonic slice suggests caution when identifying and dating partial melting in high-temperature/(ultra)high-pressure rocks.
DS2001-0420
2001
Gu, Y.Gu, Y., Dziewonski, A.M., Ekstrom, C.Preferential detection of the Lehmann discontinuity beneath continentsGeophysical Research Letters., Vol. 28, No. 24, Dec. 15, pp. 4655-58.MantleGeophysics - seismics, Discontinuity, boundary
DS2003-0515
2003
Gu, Y.Gu, Y., Anderson, J.M.Geometric processing of hyper spectral image dat a acquired by VIFIS on board lightInternational Journal of Remote Sensing, Vol. 24, 23, Dec. pp. 4681-4698GlobalVariable-Interference-Filter Imaging Spectrometer (VIFIS), airborne imaging
DS2003-0812
2003
Gu, Y.Li, X., Kind, R., Yuan, X., Sobolev, S.V., Hanka, W., Ramesh, D.S., Gu, Y.Seismic observation of narrow plumes in the oceanic upper mantleGeophysical Research Letters, Vol. 30, 6, p. 67. DOI10.1029/2002GLO15411MantlePlumes
DS200412-0737
2003
Gu, Y.Gu, Y., Anderson, J.M.Geometric processing of hyper spectral image dat a acquired nu VIFIS on board light aircraft.International Journal of Remote Sensing, Vol.24, no. 23, Dec.pp. 4681-99.TechnologyRemote sensing - hyperspectral
DS200412-1130
2003
Gu, Y.Li, X., Kind, R., Yuan, X., Sobolev, S.V., Hanka, W., Ramesh, D.S., Gu, Y., Dziewonski, A.M.Seismic observation of narrow plumes in the oceanic upper mantle.Geophysical Research Letters, Vol. 30, 6, p. 67. DOI10.1029/2002 GLO15411MantleGeophysics - seismics Plumes
DS2003-0516
2003
Gu, Y.J.Gu, Y.J., Dziewonski, A.M., Ekstrom, G.Simultaneous inversion for mantle shear velocity and topography of transition zoneGeophysical Journal International, Vol. 154, 2, pp. 559-83.MantleGeophysics - seismics, Discontinuity
DS201511-1837
2015
Gu, Y.J.Gu, Y.J., Shen, L.Noise correlation tomography of southwest western Canada sedimentary basin. Geophysical Journal International, Vol. 202, pp. 142-162.Canada, AlbertaGeophysics - seismics

Abstract: We analyse continuous recordings from 23 broadband seismic stations near Alberta, the southwestern sector of the Western Canada Sedimentary Basin. Noise correlation tomo-graphy based on vertical-component seismograms reveals below-average shear velocities at shallow and middle crustal depths in central Alberta, spanning across Proterozoic accreted terranes and Archean microcontinents. This observation likely results from extensive plate convergence and crustal melting during the Proterozoic eon. The overall correlation between the crustal velocities and presumed basement domains is lower than expected, however. In the lower crust, the main pattern of shear velocities is relatively concordant with the reported domain boundaries and key Precambrian structures appear to be intact. The shear velocities beneath the Loverna Block, the largest constituent of the Hearne craton, are 10?per?cent higher than the regional average. This prominent northeast striking seismic anomaly is moderately correlated with the regional heat flow and potentially represents the remnant core of the Archean Hearne province. The associated high velocities extend into the western part of the Medicine Hat Block, a possible Archean microcontinent with a debatable origin, and contribute to a strong east-west structural gradient in the lower crust. The presence and the continuity of this anomalous structure imply extensive communications among the various basement domains in southern Alberta during the assembly of the North American continent.
DS201602-0198
2015
Gu, Y.J.Chen, Y., Gu, Y.J., Dokht, R.M.H., Sacchi, M.D.Crustal imprints of Precambrian orogenesis in western Laurentia.Journal of Geophysical Research, Vol. 120, 10, pp. 6993-7012.Canada, AlbertaGeophysics - seismics LVZs

Abstract: Crustal low-velocity zones (LVZs) have been reported in active orogens such as the Himalayas and the Andes but rarely in stable cratonic regions. In this study, we provide compelling evidence for a significant midcrustal LVZ beneath eastern-central Alberta, an integral part of the Precambrian Canadian Shield covered by thick Phanerozoic sedimentary deposits. This 200?km wide, over 10?km thick midcrustal LVZ is well resolved by shear velocity inversions using P-to-S receiver functions from more than 4600 earthquakes. It is generally overlain by a high-velocity upper crust in the depth range of 8-15?km, especially in western-central Alberta, which coincides with the previously documented Winagami reflection sequence. We interpret the LVZ to be of granitic composition, potentially in connection with the crystallization of partially molten crust during the Paleoproterozoic eon. In addition to the Precambrian tectonic history of western Laurentia, which featured plate convergence conducive to crustal melting, our crustal model is further supported by (1) a moderate spatial correlation between the LVZ and heat flow, and (2) shear velocities consistent with that of granite. The well preserved Winagami reflection sequence and the LVZ are potential evidence of distinct episodes of magmatism and crust modification in the Precambrian basement of the Western Canada Sedimentary Basin. The existence of a broad crustal LVZ suggests extensive subduction, orogenesis, and crustal melting during the Precambrian assembly of the North American craton.
DS201702-0204
2017
Gu, Y.J.Chen, Y., Gu, Y.J., Hung, S-H.Finite frequency P-wave tomography of the western Canada sedimentary basin: implications for the lithospheric evolution in western Laurentia.Tectonophysics, Vol. 698, pp. 79-90.Canada, Alberta, SaskatchewanCraton, tomography
DS201810-2302
2018
Gu, Y.J.Chen, Y., Gu, Y.J., Hung, S-H.A new appraisal of lithospheric structures of the Cordillera craton boundary region in western Canada.Tectonics, Aug. 28, 10.1029/ 2018TC004956Canada, Alberta, Saskatchewancraton

Abstract: The Western Canada Sedimentary Basin marks a boundary zone between the Precambrian North American craton and the Phanerozoic Cordillera. Its crystalline basement has documented more than 3 billion years of evolution history of western Laurentia. Here we conduct a high?resolution survey of the mantle P and S wave velocities using finite?frequency tomography. Our models show pronounced eastward increases of 4% P and 6% S wave velocities beneath the foreland region, which define a sharp seismic Cordillera?Craton boundary. In the cratonic region, distinctive high? (>2%) velocity anomalies representing depleted mantle lithospheres are well correlated with major Precambrian crustal domains. The largest lithosphere thickness contrast coincides with the Snowbird Tectonic Zone, where the Hearne province extends down to ~300 km, nearly 100 km deeper than the Proterozoic terranes in northern Alberta. In the latter region, a pronounced cylindrical negative velocity anomaly extends subvertically from 75 to ~300?km depth, which potentially results from significant tectonothermal modifications during subduction and/or plume activities. At the basin scale, mantle velocities show no apparent correlations with surface heat flux, suggesting a minimum mantle contribution to the regional thermal variability. Furthermore, the long?wavelength isostatic gravity correlates negatively with the velocities, which confirms that the melt extraction from Precambrian cratons is responsible for the formation of highly depleted mantle lithospheres. Moreover, our model reveals the increased concentrations of kimberlites and lamproites near the zones of high horizontal velocity gradients. The distinct spatial pattern may reflect either preferential formation or eruption of potentially diamondiferous rocks at lithospheric weak zones near the western margin of Laurentia.
DS202007-1129
2020
Gu, Y/.J.Chen, Y., Gu, Y/.J., Heaman, L.M., Wu, L., Saygin, E., Hung, S-H.Reconciling seismic structures and Late Cretaceous kimberlite magmatism in northern Alberta, Canada.Geology, Vol. 48, in press available, 5 p. pdfCanada, Albertadeposit - Birch Mountain, Mountain Lake

Abstract: The Late Cretaceous kimberlites in northern Alberta, Canada, intruded into the Paleoproterozoic crust and represent a nonconventional setting for the discovery of diamonds. Here, we examined the origin of kimberlite magmatism using a multidisciplinary approach. A new teleseismic survey reveals a low-velocity (-1%) corridor that connects two deep-rooted (>200 km) quasi-cylindrical anomalies underneath the Birch Mountains and Mountain Lake kimberlite fields. The radiometric data, including a new U-Pb perovskite age of 90.3 ± 2.6 Ma for the Mountain Lake intrusion, indicate a northeast-trending age progression in kimberlite magmatism, consistent with the (local) plate motion rate of North America constrained by global plate reconstructions. Taken together, these observations favor a deep stationary (relative to the lower mantle) source region for kimberlitic melt generation. Two competing models, mantle plume and slab subduction, can satisfy kinematic constraints and explain the exhumation of ultradeep diamonds. The plume hypothesis is less favorable due to the apparent age discrepancy between the oldest kimberlites (ca. 90 Ma) and the plume event (ca. 110 Ma). Alternatively, magma generation may have been facilitated by decompression of hydrous phases (e.g., wadsleyite and ringwoodite) within the mantle transition zone in response to thermal perturbations by a cold slab. The three-dimensional lithospheric structures largely controlled melt migration and intrusion processes during the Late Cretaceous kimberlite magmatism in northern Alberta.
DS201708-1586
2017
Gu, Y-C.Zhou, Z-G., Wang, G-S., Di, Y-J., Gu, Y-C., Zhang, D., Zhu, W-P., Liu, C-F., Wu, C., Li, H-Y., Chen, L-Z.Discovery of Mesoproterozoic kimberlite from Dorbed Banner Inner Mongolia and its tectonic significance.Geological Journal, pp. 1-13.Asia, Mongoliadeposit - Longtou Shan

Abstract: Porphyritic olivine kimberlitic breccia, discovered in the Dörbed Banner of Inner Mongolia, Western China, is referred to as Longtou Shan Kimberlite in our study. This kimberlite occurs as a pipe in the Halahuogete Formation of Bayan Obo Group. Zircon U–Pb ages of Longtou Shan Kimberlite reveals a Mesoproterozoic age of ~1,552 Ma, constraining the deposition age of Halahuogete Formation to the Mesoproterozoic. Compared with Mesoproterozoic kimberlite of the ancient landmass, it can be inferred that the North China Craton is a member of the Ur ancient continent of the Columbia supercontinent. Furthermore, according to the tectonic background of the Bayan Obo Group, we raise this possibility that “Bayan Obo Aulacogen” should be renamed the “Bayan Obo Continental Rift.”
DS200412-0738
2004
Gu, Yu.J.Gu, Yu.J., Dziewonski, A.M., Ekstrom, G.Simultaneous inversion for mantle shear velocity and topography of transition zone discontinuities.Geophysical Journal International, Vol. 154, 2, pp. 559-583.MantleGeophysics - seismics, boundary
DS202008-1396
2020
Guadalupe Davalos, M.Gonzales-Jiminez, J.M., Tassara, S., Schettino, E., Roque-Rosell, J., Farre-de-Pablo, J., Saunders, J.E., Deditius, A.P., Colas, V., Rovira-Medina, J.J., Guadalupe Davalos, M., Schilling, M., Jiminez-Franco, A., Marchesi, C., Nieto, F., Proenza, J.A., GerMineralogy of the HSE in the subcontinental lithospheric mantle - an interpretive review.Lithos, in press available, 44p. PdfMantleHSE

Abstract: The highly siderophile elements (HSE: Os, Ir, Ru, Rh, Pt, Pd, Re, Au) exist in solid solution in accessory base-metal sulfides (BMS) as well as nano-to-micron scale minerals in rocks of the subcontinental lithospheric mantle (SCLM). The latter include platinum-group minerals (PGM) and gold minerals, which may vary widely in morphology, composition and distribution. The PGM form isolated grains often associated with larger BMS hosted in residual olivine, located at interstices in between peridotite-forming minerals or more commonly in association with metasomatic minerals (pyroxenes, carbonates, phosphates) and silicate glasses in some peridotite xenoliths. The PGM found inside residual olivine are mainly Os-, Ir- and Ru-rich sulfides and alloys. In contrast, those associated with metasomatic minerals or silicate glasses of peridotite xenoliths consist of Pt, Pd, and Rh bonded with semimetals like As, Te, Bi, and Sn. Nanoscale observations on natural samples along with the results of recent experiments indicate that nucleation of PGM is mainly related with the uptake of HSE by nanoparticles, nanominerals or nanomelts at high temperature (> 900?°C) in both silicate and/or sulfide melts, regardless of the residual or metasomatic origin of their host minerals. A similar interpretation can be assumed for gold minerals. Our observations highlight that nanoscale processes play an important role on the ore-forming potential of primitive mantle-derived magmas parental to magmatic-hydrothermal deposits enriched in noble metals. The metal inventory in these magmas could be related with the physical incorporation of HSE-bearing nanoparticles or nanomelts during processes of partial melting of mantle peridotite and melt migration from the mantle to overlying continental crust.
DS201312-0341
2013
Guagliardo, P.Guagliardo, P., Byrne, K.,Chapman, J.,Sudarshan, K., Samarin, S., Williams, J.Positron annihilation and optical studies of natural brown type 1 diamonds.Diamond and Related Materials, Vol. 37, pp. 37-40.TechnologyBrown diamonds
DS2002-0621
2002
Guan, H.Guan, H., Sun, M., Wilde, S.A., Zhou, X., Zhai, M.SHRIMP Uranium-Lead- zircon geochronology of the Fuping Complex: implications for formation and assembly Craton.Precambrian Research, Vol. 113, No. 1-2, Jan. pp. 1-18.ChinaCraton - North China, Geochronology
DS202106-0939
2021
Guan, H.Guan, H., Geoffroy, L., Xu, M.Magma-assisted fragmentation of Pangea: continental breakup initiation and propagation.Gondwana Research, Vol. 96, pp. 56-75. pdfMantlemagmatism

Abstract: Pre-magmatic continental extension often precedes the major magmatic expulsion of large igneous provinces (LIPs). However, the cause-and-effect relationship between pre-magmatic rifting and the extrusion of large amount of magma is controversial. It remains unclear whether magmatism arises as a consequence of passive rifting or whether it is related to active upwelling of the mantle. In addition, the relationship between the pre-magmatic stages and the final breakup, with the onset of conjugate passive margins, is ambiguous. In this study, we compiled available data from six LIPs (Central Atlantic, Karoo, Parana-Etendeka, Deccan, North Atlantic, and Afar igneous provinces) that successively occurred during the fragmentation of Pangea and found that pre-magmatic rift trends may show a high obliquity or even be orthogonal with respect to the future passive margins. We conclude that syn-magmatic rifts should not be directly correlated, both structurally and dynamically, to the ancient pre-magmatic rift phase. Furthermore, following the breakup of a supercontinent, seafloor spreading usually initiates within volcanic passive margins (VPMs) and then propagates away to create non-volcanic passive margins (NVPMs) as a consequence of the consumption and cooling of a sub-lithospheric positive thermal anomaly. Major transform faults often exist between VPMs and NVPMs, acting as a mechanical barrier to mantle melting and magmatism transportation.
DS201706-1106
2017
Guan, S.Sun, S., Hou, G., Hari, K.R., Liu, S., Guan, S.Mechanism of Paleo-Mesoproterozic rifts related to breakup of Columbia supercontinent: a paleostress field modeling.Journal of Geodynamics, Vol. 107, pp. 46-60.China, Indiacraton

Abstract: The Paleo-Mesoproterozoic Zhongtiao aulacogen in the North China Craton and Cuddapah basin in the Indian Craton, have both been interpreted as intra-continental rift formed by a mantle plume that led to the breakup of Columbia supercontinent, but the mechanism has not been completely deciphered. In this paper, the mechanism of the Zhongtiao aulacogen and Cuddapah basin related to initial breakup of Columbia has been evaluated with 2D elastic finite element models of the North China Craton and the Indian Craton. The trajectories of the horizontal maximum principal compressive stress of the best-fit model fit well with the trends of dyke swarms in the North China Craton and the Indian Craton. When the other three models generated were compared with the best-fit model, it can be found that a mantle plume beneath the Zhongtiao and Cuddapah areas played the most vital role in developing the Zhongtiao aulacogen, Cuddapah basin and initial breakup of Columbia supercontinent. The boundary subduction forces, including the northern margin of the NCC, the northwest and southwest margins of the Indian Craton are indispensable factors for the rifting and breakup, whereas the mechanical properties have little influence on these modeling results. The initial breakup of Columbia supercontinent might have been resulted from the coupling between a mantle plume upwelling and some plate tectonic forces.
DS200412-0320
2004
Guan, T.Cheng, X., Zhang, H., Huang, Z., Liu, C., Qi, L., Wenbo, L., Guan, T.Genesis of carbonatite syenite complex and REE deposit at Maoniuping, Sichuan Province, China: evidence from Pb isotope geochemiGeochemical Journal, Vol. 38, pp. 67-76.ChinaCarbonatite
DS200412-2157
2004
Guan, T.Xu, C., Zhang, H., Huang, Z., Liu, C., Qi, L.Li.W., Guan, T.Genesis of the carbonatite syenite complex and REE deposit at Maoniuping, Sichuan Province, China: evidence from Pb isotope geocGeochemical Journal, Vol. 38, pp. 67-76.China, SichuanGeochronology, carbonatite
DS200812-0290
2008
Guan, Y.Dong, S.W., Li, Q.S., Gao, R., Liu, F.T., Liu, X.C., Xue, H.M., Guan, Y.Moho mapping in the Dabie ultrahigh pressure collisional orogen, central China.American Journal of Science, Vol. 308, 4, pp. 517-528.ChinaUHP
DS201512-1978
2015
Guan, Y.Taylor, L.A., Logvinova, A.M., Howarth, G.H., Liu, Y., Peslier, A.H., Rossman, G.R., Guan, Y., Chen, Y., Sobolev, N.V.Low water contents in diamond mineral inclusions: proto-genetic origin in a dry cratonic lithosphere.Earth and Planetary Science Letters, Vol. 433, pp. 125-132.MantleNAMs Nominally Anhydrous Minerals

Abstract: The mantle is the major reservoir of Earth's water, hosted within Nominally Anhydrous Minerals (NAMs) (e.g., , , and ), in the form of hydrogen bonded to the silicate's structural oxygen. From whence cometh this water? Is the water in these minerals representative of the Earth's primitive upper mantle or did it come from melting events linked to crustal formation or to more recent metasomatic/re-fertilization events? During diamond formation, NAMs are encapsulated at hundreds of kilometers depth within the mantle, thereby possibly shielding and preserving their pristine water contents from re-equilibrating with fluids and melts percolating through the lithospheric mantle. Here we show that the NAMs included in diamonds from six locales on the Siberian Craton contain measurable and variable H2O concentrations from 2 to 34 parts per million by weight (ppmw) in olivine, 7 to 276 ppmw in clinopyroxene, and 11-17 ppmw in garnets. Our results suggest that if the inclusions were in equilibrium with the diamond-forming fluid, the water fugacity would have been unrealistically low. Instead, we consider the H2O contents of the inclusions, shielded by diamonds, as pristine representatives of the residual mantle prior to encapsulation, and indicative of a protogenetic origin for the inclusions. Hydrogen diffusion in the diamond does not appear to have modified these values significantly. The H2O contents of NAMs in mantle xenoliths may represent some later metasomatic event(s), and are not always representative of most of the continental lithospheric mantle. Results from the present study also support the conclusions of Peslier et al. (2010) and Novella et al. (2015) that the dry nature of the SCLM of a craton may provide stabilization of its thickened continental roots.
DS201602-0245
2016
Guan, Y.Taylor, L.A., Logvinova, A.M., Howarth, G.H., Liu, Y., Peslier, A.H., Rossman, G.R., Guan, Y., Chen, Y., Sobolev, N.V.Low water contents in diamond mineral inclusions: proto-genetic origin in a dry cratonic lithosphere.Earth and Planetary Science Letters, Vol. 433, pp. 125-132.Russia, AfricaKaapvaal and Siberian SCLMs

Abstract: The mantle is the major reservoir of Earth's water, hosted within Nominally Anhydrous Minerals (NAMs) (e.g., , , and ), in the form of hydrogen bonded to the silicate's structural oxygen. From whence cometh this water? Is the water in these minerals representative of the Earth's primitive upper mantle or did it come from melting events linked to crustal formation or to more recent metasomatic/re-fertilization events? During diamond formation, NAMs are encapsulated at hundreds of kilometers depth within the mantle, thereby possibly shielding and preserving their pristine water contents from re-equilibrating with fluids and melts percolating through the lithospheric mantle. Here we show that the NAMs included in diamonds from six locales on the Siberian Craton contain measurable and variable H2O concentrations from 2 to 34 parts per million by weight (ppmw) in olivine, 7 to 276 ppmw in clinopyroxene, and 11-17 ppmw in garnets. Our results suggest that if the inclusions were in equilibrium with the diamond-forming fluid, the water fugacity would have been unrealistically low. Instead, we consider the H2O contents of the inclusions, shielded by diamonds, as pristine representatives of the residual mantle prior to encapsulation, and indicative of a protogenetic origin for the inclusions. Hydrogen diffusion in the diamond does not appear to have modified these values significantly. The H2O contents of NAMs in mantle xenoliths may represent some later metasomatic event(s), and are not always representative of most of the continental lithospheric mantle. Results from the present study also support the conclusions of Peslier et al. (2010) and Novella et al. (2015) that the dry nature of the SCLM of a craton may provide stabilization of its thickened continental roots.
DS201610-1874
2016
Guan, Y.Jean, M.M., Taylor, L.A., Howarth, G.H., Peslier, A.H., Fedele, L., Bodnar, R.J., Guan, Y., Doucet, L.S., Ionov, D.A., Logvinova, A.M., Golovin, A.V., Sobolev, N.V.Olivine inclusions in Siberian diamonds and mantle xenoliths: contrasting water and trace -element contents.Lithos, in press available 11p.Russia, SiberiaDiamond inclusions
DS1994-0335
1994
Guang Hong XiCong-Qiang Liu, Masuda, A., Guang Hong XiMajor and trace element compositions of Cenozoic basalts in China:petrogenesis and mantle source.Chemical Geology, Vol. 114, pp. 19-42.ChinaXenoliths, Mineral chemistry
DS202010-1838
2020
Guangfu, C.Deng, L., Geng, X., Liu, Y., Zong, K., Zhu, L., Zhengwei, L., Hu, Z., Guodong, Z., Guangfu, C.Lithospheric modification by carbonatitic to alkaline melts and deep carbon cycle: insights from peridotite xenoliths of eastern China.Lithos, in press available 38p. PdfChinacarbonatite

Abstract: Carbonates in subducting oceanic slabs can survive beyond slab dehydration and be transferred into the deep mantle. Such deep carbon cycling plays a critical role in generating carbonatitic to alkaline melts. However, whether and how this process has influenced the lithospheric mantle still remains enigmatic. To address these issues, here we provide a detailed petrographic, in-situ chemical and Sr isotopic study on two mantle xenoliths (a wehrlite and a melt pocket-bearing peridotite) entrained by the Changle Miocene basalts from the eastern China. The Changle wehrlite contains carbonate melt inclusions and apatites and is merely enriched in clinopyroxene relative to the lherzolites. The clinopyroxenes are characterized by high (La/Yb)N (4.7-41) and low Ti/Eu (873-2292) ratios and equilibrated with carbonated silicate melt-like compositions. These petrographic and chemical features indicate that the wehrlite was formed by reaction between peridotite and carbonated silicate melts. On the other hand, the Changle melt pocket-bearing peridotite is suggested to have been produced by in-situ melting/breakdown of amphiboles of an amphibole-rich dunite. Low olivine Fo (~89), presence of amphiboles with high (La/Yb)N (~50) and low Ti/Eu (~1070) ratios suggest that such amphibole-rich dunite would have been formed by reaction of peridotite with hydrous alkaline basaltic melts from a carbonated mantle. Our data, combined with previously reported data of the Changle lherzolite xenoliths, unravel a series of mantle metasomatisms by carbonatitic to alkaline melts from carbonated mantle sources. The consistently high 87Sr/86Sr ratios (up to 0.7036) of the clinopyroxenes in both the wehrlites and lherzolites indicate the carbonate components in the mantle sources were derived from the stagnant Pacific slab within the Mantle Transition Zone. This study provides a fresh perspective on the role of deep carbon cycling from subducted oceanic slabs in chemical modification of intracontinental lithospheric mantle through reaction with different types of melts.
DS1992-1520
1992
Guanghong, X.Tatsumoto, M., Basu, A.R., Wankang, H., Junwen, W., Guanghong, X.Strontium, neodymium, lead isotopes of ultramafic xenoliths in volcanicEarth and Planetary Science Letters, Vol. 113, No. 1-2, September pp. 107-128ChinaGeochronology, Xenoliths
DS1988-0276
1988
Guanghua ZouGuanghua ZouIntegrated geophysical and geochemical exploration in ChinaExploration 87, Proceedings Volume, Ontario Geological Survey, Special Publishing No. 3, pp. 771-781ChinaGeneral, Gold
DS201707-1332
2016
Guangming, Y.Guowu, L., Guangming, Y., Fude, L., Ming, X., Xiangkun, G., Baoming, P., Fourestier, J.Fluorcalciopyrochlore, a new mineral species from Bayan Obo, inner Mongolia, P.R. China.The Canadian Mineralogist, Vol. 54, pp. 1285-1291.China, Mongoliacarbonatite - Bayan Obo

Abstract: Fluorcalciopyrochlore, ideally (Ca,Na)2Nb2O6F, cubic, is a new mineral species (IMA2013-055) occurring in the Bayan Obo Fe-Nb-REE deposit, Inner Mongolia, People's Republic of China. The mineral is found in a dolomite-type niobium rare-earth ore deposit. Associated minerals are dolomite, aegirine, riebeckite, diopside, fluorite, baryte, phlogopite, britholite-(Ce), bastnäsite-(Ce), zircon, magnetite, pyrite, fersmite, columbite-(Fe), monazite-(Ce), rutile, and others. Crystals mostly form as octahedra {111}, dodecahedra {110}, and cubes {100}, or combinations thereof, and generally range in size from 0.01 to 0.3 mm. It is brownish-yellow to reddish-orange in color with a light yellow streak. Crystals of fluorcalciopyrochlore are translucent to transparent with an adamantine to greasy luster on fractured surfaces. It has a conchoidal fracture. No parting or cleavage was observed. The Mohs hardness is 5, and the calculated density is 4.34(1) g/cm3. The empirical formula is (Ca1.14Na0.74Ce0.06Sr0.03Th0.01Fe0.01Y0.01La0.01Nd0.01)?2.02(Nb1.68Ti0.29Zr0.02Sn0.01)?2.00O6.00(F0.92O0.08)?1.00 on the basis of 7(O,F) anions pfu. The simplified formula is (Ca,Na)2Nb2O6F. The strongest four reflections in the X-ray powder-diffraction pattern [d in Å (I) hkl] are: 6.040 (9) 1 1 1, 3.017 (100) 2 2 2, 2.613 (17) 0 0 4, 1.843 (29) 0 4 4, and 1.571 (15) 2 2 6. The unit-cell parameters are a 10.4164(9) Å, V 1130.2(2) Å3, Z = 8. The structure was solved and refined in space group FdEmbedded Image m with R = 0.05. The type material is deposited in the Geological Museum of China, Beijing, People's Republic of China, catalogue number M12182.
DS201601-0048
2015
Guang-Shu, L.Wang, S-J., Teng, F-Z., Rudnick, R.L., Guang-Shu, L.Magnesium isotope evidence for recycled origin of cratonic eclogites. KoiduGeology, Vol. 43, 12, pp. 1071-1074.Africa, Sierra LeoneDeposit - Koidu

Abstract: The Mg isotopic compositions of garnet and clinopyroxene mineral separates and whole rocks from 21 xenolithic eclogites (11 low-MgO eclogites and 10 high-MgO eclogites) from the Koidu kimberlite complex, erupted within the Archean Man Shield, Sierra Leone, West Africa, provide new evidence bearing on the origin of cratonic eclogites. Garnet and clinopyroxene in both low-MgO and high-MgO eclogites generally record equilibrium inter-mineral Mg isotope partitioning, with ?26Mg varying from -2.15‰ to -0.46‰ in garnets and from -0.49‰ to +0.35‰ in clinopyroxenes. Bulk ?26Mg values (-1.38‰-to +0.05-), constructed from garnet and clinopyroxene data, are similar to results from rock powders (-1.60‰ to +0.17‰), suggesting that kimberlite infiltration has had negligible influence on the Mg isotopic compositions of the xenoliths. The ?26Mg values of low-MgO eclogites (-0.80‰ to +0.05‰) exceed the range of mantle peridotite xenoliths (-0.25- ± 0.04-), consistent with the eclogite’s derivation from recycled altered oceanic crust. Similarly variable ?26Mg values in high-MgO eclogites (-0.95‰ to -0.13‰), together with their high MgO and low FeO contents, suggest that high-MgO eclogites were produced by Mg-Fe exchange between partially molten low-MgO eclogites and surrounding peridotites. Our study shows that cratonic xenolithic eclogites preserve a record of Mg isotopic compositions produced by low-pressure, surficial isotope fractionations. The recycling of oceanic crust therefore increases the Mg isotope heterogeneity of the mantle.-
DS1995-2144
1995
Guanliang, L.Zheng, P., Guanliang, L.Lamproites in the Yangtze Craton, ChinaProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 684-686.ChinaLamproites, Craton -Yangtze
DS1997-0450
1997
Guanliang, L.Guanliang, L., et al.Carbon isotopic composition and genesis of diamondProceedings 30th. I.G.C., Pt. 15, pp. 87-100.ChinaPlacers, alluvials, geochronology, Diamond genesis
DS1993-0588
1993
Guardian WeeklyGuardian WeeklyRussia wants a cut of the diamond actionGuardian Weekly, November 28, 3p.Russia, YakutiaNews item, Diamond markets
DS201012-0493
2010
Guarino, V.Melluso, L., Srivastava, R.K., Guarino, V., Zanetti, A., Sinha, A.K.Mineral compositions and petrogenetic evolution of the ultramafic alkaline carbonatitic complex of Sung Valley, northeastern India.The Canadian Mineralogist, Vol. 48, 2, pp. 205-229.IndiaCarbonatite
DS201112-0391
2011
Guarino, V.Guarino, V., Azzone, Brotzu, De Barros, Melluso, L., Morbidelli, Ruberti, Tassinari, BrilliMagmatism and fenitization in the Cretaceous potassium alkaline carbonatitic complex of Ipanema, Sao Paulo State, Brazil.Mineralogy and Petrology, In press available,South America, BrazilCarbonatite
DS201212-0267
2012
Guarino, V.Guarino, V., Guitarrari Azzone, R., Brotzu, P., Celso de Barros Gomes, Melluso, L., Morbidelli, L.,Ruberti, E.,Tassinari, C., Brilli, M.Magmatism and fenitization in the Cretaceous potassium-alkaline-carbonatitic complex of Ipanema Sao Paulo State, Brazil.Mineralogy and Petrology, Vol. 104, 1-2, pp. 43-61.South America, BrazilCarbonatite
DS201212-0268
2012
Guarino, V.Guarino, V., Wu, F-Y., Lustrino, M., Melluso, L.,Brotzu, P., De Barros Gomes, C., Ruberti, E., Tassarini, C.C.G., Svisero, D.P.U Pb ages, Sr Nd isotope geochemistry, and petrogenesis of kimberlites, kamafugites and phlogopite picrites of the Alto Paranaiba Igneous Province, Brazil.Chemical Geology, in press available 57p.South America, BrazilGeochronology
DS201212-0461
2012
Guarino, V.Melluso, L., Rajesh,K., Srivastava, C.M., Petrone, V., Guarino, V., Sinha, A.K.Mineralogy, magmatic affnity and evolution of the Early Cretaceous alkaline complex of Jasra, Shillong Plateau, northeastern India.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractIndiaDeposit - Jasra
DS201212-0700
2012
Guarino, V.Srivasta, R.K., Melluso, L., Petrone, C.M., Guarino, V., Sinha, A.K.Evolution of the Early Cretaceous alkaline Jasra complex, Shillong Plateau, northeastern India.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractIndiaDeposit - Jasra
DS201312-0350
2013
Guarino, V.Guarino, V., Wu, F-Y., Lustrino, M., Melluso, L., Brotzu, P., Barros Gomes, C.de, Ruberti, E., Tassarini, C.C.G., Svisero, D.P.U-Pb ages, Sr, Nd isotope geochemistry, and petrogenesis of kimberlites, kamafugites and phlogopte-picrites of the Alto Paranaiba Igneous Province, Brazil.Chemical Geology, Vol. 353, pp. 65-82.MantleUHP
DS201705-0853
2017
Guarino, V.Melluso, L., Guarino, V., Lustrino, M., Morra, V., de'Gennaro, R.The REE- and HFSE-bearing phases in the Itatiaia alkaline complex ( Brazil) and geochemical evolution of feldspar-rich felsic melts.Mineralogical Magazine, Vol. 81, 2, pp. 217-250.South America, BrazilAlkaline rocks

Abstract: The Late Cretaceous Itatiaia complex is made up of nepheline syenite grading to peralkaline varieties, quartz syenite and granite, emplaced in the metamorphic rocks of the Serra do Mar, SE Brazil. The nepheline syenites are characterized by assemblages with alkali feldspar, nepheline, Fe-Ti oxides, clinopyroxene, amphibole, apatite and titanite, while the peralkaline nepheline syenites have F-disilicates (rinkite, wöhlerite, hiortdahlite, låvenite), britholite and pyrophanite as the accessory phases. The silica-oversaturated rocks have alkali feldspar, plagioclase, quartz, amphibole, clinopyroxene and Fe-Ti oxides; the chevkinite-group minerals are the featured accessory phases and are found with allanite, fluorapatite, fluorite, zircon, thorite, yttrialite, zirconolite, pyrochlore and yttrocolumbite. The major- and trace-element composition of the Itatiaia rocks have variations linked to the amount of accessory phases, have smooth, enriched chondrite-normalized rare-earth element (REE) distribution patterns in the least-evolved nepheline syenites and convex patterns in the most-evolved nepheline syenites. The REE distribution patterns of the quartz syenites and granites show a typical pattern caused by fractional crystallization of feldspar and amphibole, in an environment characterized by relatively high oxygen fugacity (>NiNiO buffer) and high concentrations of H2O and F, supporting the crystallization of hydrous phases, fluorite and F-disilicates. The removal of small amounts of titanite in the transition from the least-evolved to the most-evolved nepheline syenites stems from petrogenetic models involving REE, and is shown to be a common feature of the magmatic evolution of many other syenitic/ trachytic/ phonolitic complexes of the Serra do Mar and elsewhere.
DS201709-1994
2017
Guarino, V.Guarino, V., Wu, F-Y., Melluso, L., de Barros Gomes, C., Tassinari, C.C.G., Ruberti, E., Brilli, M.U Pb ages, geochemistry, C-O-Nd-Sr-Hf isotopes and petrogeneis of the Catalao II carbonatitic complex ( Alto Paranaiba igneous province, Brazil): implucations for regional scale heterogeneities in the Brazilian carbonatite associations.International Journal of Earth Sciences, Vol. 106, 6, pp. 1963-1989.South America, Brazilcarbonatite - Catalao II

Abstract: The Catalão II carbonatitic complex is part of the Alto Paranaíba Igneous Province (APIP), central Brazil, close to the Catalão I complex. Drill-hole sampling and detailed mineralogical and geochemical study point out the existence of ultramafic lamprophyres (phlogopite-picrites), calciocarbonatites, ferrocarbonatites, magnetitites, apatitites, phlogopitites and fenites, most of them of cumulitic origin. U–Pb data have constrained the age of Catalão I carbonatitic complex between 78 ± 1 and 81 ± 4 Ma. The initial strontium, neodymium and hafnium isotopic data of Catalão II (87Sr/86Sri= 0.70503–0.70599; ?Ndi= ?6.8 to ?4.7; 176Hf/177Hf = 0.28248–0.28249; ?Hfi= ?10.33 to ?10.8) are similar to the isotopic composition of the Catalão I complex and fall within the field of APIP kimberlites, kamafugites and phlogopite-picrites, indicating the provenance from an old lithospheric mantle source. Carbon isotopic data for Catalão II carbonatites (?13C = ?6.35 to ?5.68 ‰) confirm the mantle origin of the carbon for these rocks. The origin of Catalão II cumulitic rocks is thought to be caused by differential settling of the heavy phases (magnetite, apatite, pyrochlore and sulphides) in a magma chamber repeatedly filled by carbonatitic/ferrocarbonatitic liquids (s.l.). The Sr–Nd isotopic composition of the Catalão II rocks matches those of APIP rocks and is markedly different from the isotopic features of alkaline-carbonatitic complexes in the southernmost Brazil. The differences are also observed in the lithologies and the magmatic affinity of the igneous rocks found in the two areas, thus demonstrating the existence of regional-scale heterogeneity in the mantle sources underneath the Brazilian platform.
DS201904-0783
2019
Guarino, V.Srivastava, R.K., Guarino, V., Wu, F-Y., Melluso, L., Sinha, A.K.Evidence of sub continental lithospheric mantle sources and open system crystallization processes from in situ U-Pb ages and Nd-Sr-Hf isotope geochemistry of the Cretaceous ultramafic alkaline (carbonatite) intrusions from the Shillong Plateau, north-eastLithos, Vol. 330, 1, pp. 108-119.Indiacarbonatite

Abstract: New in-situ U-Pb ages and Sr-Nd-Hf isotopic data on mineral phases of the Sung Valley and Jasra ultramafic-alkaline-(carbonatite) intrusions (Shillong Plateau, India) shed new light on the petrogenetic processes of volcanism in north-eastern India during the Cretaceous. Perovskites of Sung Valley dunite, ijolite and uncompahgrite yielded U-Pb ages of 109.1?±?1.6, 104.0?±?1.3 and 101.7?±?3.6?Ma, respectively. A U-Pb age of 106.8?±?1.5?Ma was obtained on zircons of a Sung Valley nepheline syenite. Perovskite of a Jasra clinopyroxenite yielded an age of 101.6?±?1.2?Ma, different from the U-Pb age of 106.8?±?0.8?Ma on zircon of Jasra syenites. The variation in Sr-Nd-Hf isotopic compositions [initial 87Sr/86Sr?=?0.70472 to 0.71080; ?Nd i?=??10.85 to +0.86; ?Hf i?=??7.43 to +1.52] matches the bulk-rock isotopic composition of the different rock units of Sung Valley and Jasra. Calcite and apatite in the carbonatites, the perovskite in a dunite, and the bulk-rock carbonatites of Sung Valley intrusion have the lowest initial 87Sr/86Sr and ?Nd, taken to be the best proxies of the mantle source composition, which is dominated by components derived from the lithospheric mantle. The alkaline intrusions of north-eastern India are significantly younger than the Sylhet tholeiitic magmatism. The silicate rocks of both intrusions have isotopic composition trending to that of the underlying Shillong crust, indicating the effects of fractional crystallization and low-pressure crustal contamination during the emplacement of the various intrusive magma pulses.
DS202110-1610
2021
Guarino, V.de Barros Gomes, C., Azzone, R.G., Rojas, G.E.E., Guarino, V., Ruberti, E.Agpaitic alkaline rocks in southern Brazilian platform: a review.Minerals MDPI, Vol. 11, 934, 30p. PdfSouth America, Brazil, Paraguayalkaline magmatism

Abstract: General information is presented on ten agpaitic occurrences located in southern Brazil and at the border between Brazil and Paraguay. All the Brazilian agpaitic rocks are Late Cretaceous in age, whereas the Paraguayan ones are older than Early Triassic. The most significant occurrence is Poços de Caldas, the largest alkaline massif in South America. In general, these agpaitic rocks contain mineral assemblages that indicate presence of typical halogen-bearing Na-Ca-HFSE phases, eudialyte-, rinkite- and wöhlerite-group minerals being the most frequent ones. However, these associations are indeed more complex in terms of composition, with accessory phases in some cases consisting of various minerals, including U-Th oxides/silicates, Nb oxides, REE-Sr-Ba bearing carbonates-fluorocarbonates-phosphates-silicates and Zr-Na rich silicates. They usually form late magmatic stage to hydrothermal/deuteric assemblages linked with coarse and fine-grained, mainly silica-undersaturated evolved rocks. Data also indicate significant differences in type, amount and composition of agpaitic minerals in all investigated occurrences.
DS202205-0720
2022
Guarino, V.Srivastava, R.K., Guarino, V., Melluso, L.Early Cretaceous ultramafic-alkaline-carbonatite magmatism in the Shilong Plateau-Mikir Hills, northeastern India - a synthesis.Mineralogy and Petrology, 10.1007/s00710-022-00777-z 20p. PdfIndiadeposit - Shilong Plateau

Abstract: A comprehensive mineralogical, geochemical and isotopic review of six ultramafic-alkaline-carbonatite magmatic intrusions of the Shillong Plateau (Sung Valley, Jasra, Swangkre-Rongjeng, and Mawpyut) and Mikir Hills (Samchampi-Samteran and Barpung) is presented here, using the published data. These intrusions emplaced ca. 115-102 Ma ago, thus are significantly younger than the tholeiitic flood basalts erupted in Rajmahal-Sylhet province (ca. 118-115 Ma). The intrusive lithologies vary from ultramafic (dunites, clinopyroxenites, melilitolites) to mafic (ijolites, gabbros sensu lato, shonkinites), to felsic (syenites, nepheline syenites) and carbonatites (mostly calcite-rich varieties). The volcanic-subvolcanic facies (lamprophyres, phonolites) are not abundant. The range of chemical compositions of the magmatic phases in the various assemblages is notable; the intrusive rocks are thus the result of crystallization of magmas from variably evolved, independent liquid-lines-of descent, generally of alkaline/strongly alkaline lineages and sodic-to-potassic in affinity. The large variations of the Sr-Nd isotopic ratios of the silicate intrusive rocks (sensu lato) suggest a role of shallow-level crustal contamination during their formation. The carbonatites of the Sung Valley and Samchampi-Samteran have different isotope ratios than the associated silicate rocks, have some isotopic affinity with the Group I tholeiitic basalts of Rajmahal Traps and have an ultimate genesis in a carbonate-bearing lithospheric mantle.
DS1997-0451
1997
Guarnera, B.J.Guarnera, B.J.Issues and trends in privitization in the International mineral industry.Presentation by Behre DolbearMiga Conference Held Denver June 3-5, 23pAfricaMining, discoveries, Economics - privitization
DS1997-0452
1997
Guarnera, B.J.Guarnera, B.J.Technical flaws in bankable documents. Bank risk, country risk, companyrisk, technical and mining riskAssaying and Reporting Conference Nov. 10-11, 1997 Singapore, 16pGlobalSampling, assaying, ore reserves, discoveries, Geostatistics, gold, economics, financial
DS1998-0545
1998
Guarnera, B.J.Guarnera, B.J.Valuing mining companies: why should we be different?Pros. Developers Assoc, Short course pp. 1-17GlobalReserves, discoveries, success, Valuation
DS201901-0079
2018
Guastella, L.A.Smith, A.M., Guastella,L.A., Botes, Z.A.Submarine mass flow channels as an underlying control for headland-bound embayments southeastern African coastline.South African Journal of Geology, Vol. 121, pp. 227-236.Africa, South Africageomorphology

Abstract: Rocky reaches of the southeast African coastline are characterized mainly by log-spiral and headland-bound bays. Extensive fieldwork was carried out to investigate both documented and new exposures of Cretaceous beds on the southern KwaZulu-Natal and upper Eastern Cape (Transkei) coasts. Our results suggest that geological inheritance plays an important role in the contemporary rocky coast geomorphology. We offer evidence that post-Gondwana break-up mass flow channels play an important role in the present southeast African coastline morphology. Mass flow channels contain fills of incompetent Cretaceous rocks which are being preferentially eroded by prevailing marine and fluvial processes to form headland-bound embayment landforms. This study has identified an important geomorphic process for the development of the current southeast African coastline.
DS200412-0739
2004
Guay, K.Guay, K.The diamond diplomat... Shelly Purdy as spokesperson for the jewellery industry.Canadian Diamonds., Spring, pp. 22-28.CanadaNews item - jeweller
DS2001-0421
2001
Guaynor Resources S.A.Guaynor Resources S.A.Mr. M. Juilland has been appointed PresidentGuyanor Res. S.A., Aug. 7, 1p.French GuianaNews item - press release
DS1999-0485
1999
Gubala, C.P.Mitescu, B., Halls, H.C., Gubala, C.P.A gravity study of the northwestern boundary fault of the Kapuskasing structural Zone.Geological Association of Canada (GAC) Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC)., Vol. 24, p. 92. abstractOntarioTectonics, structure, Ivanhoe Fault, Midcontinent
DS200512-0721
2004
Gubanov, A.P.Metelkin, D.V., Vernikovsky, V.A., Kazansky, A.Y., Bogolepova, O.K., Gubanov, A.P.Paleozoic history of the Kara microcontinent and its relation to Siberia and Baltica: paleomagnetism, paleogeography and tectonics.Tectonophysics, Vol. 398, 3-4, April 13, pp. 225-243.Russia, Siberia, Baltic ShieldTectonics
DS200412-0740
2003
Gubarevich, A.V.Gubarevich, A.V., Akhremkova, G.S., Lapina, V.A.Properties of the surface of ultrafine diamonds.Russian Journal of Physical Chemistry, Vol. 77, 11, pp. 1832-36. Ingenta 1035296891TechnologyDiamond morphology
DS1996-0020
1996
Gubbels, T.Allmendiger, R.W., Gubbels, T.Pure and simple shear plateau uplift, Altiplano -Puna, Argentin a andBoliviaTectonophysics, Vol. 259, No. 1-3, June 30, pp. 1-14Argentina, BoliviaTectonics
DS1993-0589
1993
Gubbels, T.L.Gubbels, T.L., Isaacks, B.L., Farrar, E.High level surfaces, plateau uplift, and foreland development, Bolivian central AndesGeology, Vol. 21, No. 8, August pp. 695-698BoliviaTectonics, San Juan Del Oro surface
DS1989-0128
1989
Gubbins, D.Bloxham, J., Gubbins, D.The evolution of the earth's magnetic fieldScientific American, Vol. 261, No. 6, December pp. 68-75GlobalGeophysics, Overview - magnetic fields
DS1991-0619
1991
Gubbins, D.Gubbins, D.Seismology and plate tectonicsCambridge University Press, 340p. $ paperback approx. $ 50.00GlobalGeophysics, Seismology
DS1991-0620
1991
Gubbins, D.Gubbins, D.Sesimology and plate tectonicsCambridge University Press, 340p. $ paperback approx. $ 50.00GlobalGeophysics, Seismology
DS1991-0621
1991
Gubbins, D.Gubbins, D.Core-mantle interactionsTectonophysics, Vol. 187, pp. 385-391GlobalMantle, Geophysics -magnetics
DS1991-0622
1991
Gubbins, D.Gubbins, D., Snieder, R.Dispersion of P waves in subducted lithosphere: evidence for an eclogitelayerJournal of Geophysical Research, Vol. 96, No. B 4, April 10, pp. 6321-6335GlobalMantle, Eclogites
DS1993-0590
1993
Gubbins, D.Gubbins, D., Kelly, P.Persistent patterns in the geomagnetic field over the past 2.5 MyrNature, Vol. 365, October 28, pp. 829-891.MantleGeophysics, Geomagnetics
DS1994-0670
1994
Gubbins, D.Gubbins, D.Geomagnetic polarity reversals: a connection with secular variation and core-mantle interaction?Reviews of Geophysics, Vol. 32, No. 1, February pp. 61-84MantleGeophysics, Geophysics -magnetics, Paleomagnetism
DS1994-0671
1994
Gubbins, D.Gubbins, D., Barnicoat, A., Cann, J.Seismological constraints on the gabbro-eclogite transition in subducted eclogite crust.Earth and Planet. Science Letters, Vol. 122, No. 1/2, March pp. 89-102.MantleEclogite, Subduction
DS2001-0422
2001
Gubbins, D.Gubbins, D.The rayleigh number for convection in the Earth's corePhysics of the Earth and Planetary Interiors, Vol. 128, No. 1-4, Dec. 10, pp. 3-12.MantleConvection
DS200412-0741
2004
Gubbins, D.Gubbins, D., Alfe, D., Masters, G., Price, G.D., Gillan, M.Gross thermodynamics of two component core convection.Geophysical Journal International, Vol. 157, 3, pp. 1407-1414.MantleConvection
DS200412-1435
2004
Gubbins, D.Nimmo, F., Price, G.D., Brodholt, J., Gubbins, D.The influence of potassium on core and geodynamo evolution.Geophysical Journal International, Vol. 156, 2, pp. 363-376.MantleMineralogy
DS200612-0508
2006
Gubbins, D.Gubbins, D.Encyclopedia of geomagnetism and paleomagnetism.Springer, 1022p. $ 400. ISBN 1-4020-3992-1TechnologyBook - geophysics, magnetism
DS200712-0392
2007
Gubbins, D.Gubbins, D.Geomagnetic constraints on stratification at the top of Earth's core.Earth Planets and Space, Vol. 59, 7, pp. 661-664.MantleConvection
DS200712-0393
2007
Gubbins, D.Gubbins, D., Willis, A.P., Sreenivasan, B.Correlation of Earth's magnetic field with lower mantle thermal and seismic structure.Physics of the Earth and Planetary Interiors, Vol. 162, 3-4, pp. 256-260.MantleGeophysics - seismics
DS200712-0394
2007
Gubbins, D.Gubbins, D., Willis, A.P., Sreenivasan, B.Correlation of Earth's magnetic field with lower mantle thermal and seismic structure.Physics of the Earth and Planetary Interiors, Vol. 162, 3-4, pp. 256-260.MantleGeophysics - seismics
DS200712-1159
2007
Gubbins, D.Willis, A.P., Sreenivasan, B., Gubbins, D.Thermal core mantle interaction: exploring regimes for 'locked' dynamo action.Physics of the Earth and Planetary Interiors, Vol. 165, 1-2, pp. 83-92.MantleGeodynamics
DS200812-0265
2008
Gubbins, D.Davies, C.J., Gubbins, D., Willis, A.P., Jimack,P.K.Time averaged paleomagnetic field and secular variation: prediction from dynamo solutions based on lower mantle seismic tomography.Physics of the Earth and Planetary Interiors, Vol. 169, 1-4, pp. 194-203.MantleGeophysics - seismics
DS200812-0435
2008
Gubbins, D.Gubbins, D., Masters, G., Nimmo, F.A thermochemical boundary layer at the base of Earth's outer core and independent estimate of core heat flux.Geophysical Journal International, Vol. 174, 3m pp. 1007-1018.MantleGeothermometry
DS201112-0241
2011
Gubbins, D.Davies, C.J., Gubbins, D.A bouyancy profile for the Earth's core.Geophysical Journal International, In press availableMantleGeophysics - seismics
DS201112-0392
2011
Gubbins, D.Gubbins, D.A bouyancy profile for the Earth's core.Geophysical Journal International, Vol. 187, 2, pp. 549-563.MantleCore
DS201212-0571
2012
Gubbins, D.Pozzo, M., Davies, C., Gubbins, D., Alfe, D.Thermal and electrical conductivity of iron at Earth's core.Nature, in press availableMantleGeothermometry
DS201412-0708
2014
Gubbins, D.Pozzo, M., Davies, C., Gubbins, D., Alfe, D.Thermal and electrical conductivity of solid iron and iron-silicon mixtures at Earth's core conditions.Earth and Planetary Science Letters, Vol. 393, pp. 159-165.MantleGeothermometry
DS201509-0392
2015
Gubbins, D.Davies, C., Pozzo, M., Gubbins, D., Alfe, D.Constraints from material properties on the dynamics and evolution of Earth's core.Nature Geoscience, Vol. 8, pp. 678-785.MantleHT - core evolution

Abstract: The Earth’s magnetic field is powered by energy supplied by the slow cooling and freezing of the liquid iron core. Efforts to determine the thermal and chemical history of the core have been hindered by poor knowledge of the properties of liquid iron alloys at the extreme pressures and temperatures that exist in the core. This obstacle is now being overcome by high-pressure experiments and advanced mineral physics computations. Using these approaches, updated transport properties for FeSiO mixtures have been determined at core conditions, including electrical and thermal conductivities that are higher than previous estimates by a factor of two to three. Models of core evolution with these high conductivities suggest that the core is cooling much faster than previously thought. This implies that the solid inner core formed relatively recently (around half a billion years ago), and that early core temperatures were high enough to cause partial melting of the lowermost mantle. Estimates of core-mantle boundary heat flow suggest that the uppermost core is thermally stratified at the present day.
DS1981-0299
1981
Gubelin, E.Meyer, H.O.A., Gubelin, E.Ruby in DiamondGems And Gemology, FALL, PP. 153-156.GlobalInclusions, Natural Diamond, Morphology
DS1982-0228
1982
Gubelin, E.Gubelin, E.Mineral Inclusions Contribute Towards Elucidating the Genesis of the Diamond.Journal of Gemology AND Proceedings Association GREAT BRITAIN., Vol. 18, No. 4, PP. 297-320.GlobalGenesis
DS1986-0314
1986
Gubelin, E.Gubelin, E., Koivula, J.I.Photoatlas of inclusions in gemstones #2Gemological Institute of America (GIA), 532p. ISBN 3-85504-095-8GlobalDiamond morphology, Inclusions
DS1989-0555
1989
Gubelin, E.Gubelin, E.World map of gemstone depositsIndiaqua, No. 53, 1989/II, p. 157GlobalMap -gemstones, Advertisement
DS1975-0752
1978
Gubelin, E.J.Gubelin, E.J., Meyer, H.O.A., Tsai, H.M.Natur und Bedeutung der Mineral Einschluesse im Naturlichendiamanten.Zeitschr. Deut. Gemmol. Ges., Vol. 27, No. 2, PP. 61-101.GlobalNatural Diamond, Inclusions, Major Element Chemistry, Mineralogy
DS1986-0315
1986
Gubelin, E.J.Gubelin, E.J., Koivula, J.I.Photoatlas of inclusions in gemstones #1Zurich, ABC edition, 532pGlobalIllustrated catalogue, Gemology
DS1988-0371
1988
Guberman, D.M.Kozlovskiy, Ye.A., Guberman, D.M., Kazanskiy, V.I., Lanev, V.S.The ore potential of deep seated zones of ancient continental crust Based on dat a from the Kola Superdeep drillholeInternational Geology Review, Vol. 30, No. 7, July pp. 763-771. Database # 17694RussiaOre deposits, Genesis
DS1997-0453
1997
Gubins, A.G.Gubins, A.G.Geophysics and geochemistry at the Millenium.. proceedings of Exploration97, Fourth Decennial ConfExploration 97, 1070p. approx. $ 175.00GlobalBook - Table of contents, Exploration 97
DS2002-1099
2002
GuckertMossman, D.J., Eigendorf, G., Tokarvk, D., Gauthier-Lafave, Guckert, MelezhikThe search for fullerenes in carbonaceous substances associated with the natural11th. Quadrennial Iagod Symposium And Geocongress 2002 Held Windhoek, Abstract p. 38.GabonFullerenes
DS201603-0373
2016
Gucsik, A.Dongre, A.N., Viljoen, K.S., Chalapathi Rao, N.V., Gucsik, A.Origin of Ti rich garnets in the groundmass of Wajrakarur field kimberlites, southern India: insights from EPMA and Raman spectroscopy.Mineralogy and Petrology, in press available, 13p.IndiaDeposit - Wajrakur

Abstract: Although Ti-rich garnets are commonly encountered in the groundmass of many alkaline igneous rocks, they are comparatively rare in kimberlites. Here we report on the occurrence of Ti-rich garnets in the groundmass of the P-15 and KL-3 kimberlites from the diamondiferous Wajrakarur field in the Eastern Dharwar craton of southern India. These garnets contain considerable Ti (11.7-23.9 wt.% TiO2), Ca (31.3-35.8 wt.% CaO), Fe (6.8-15.5 wt.% FeOT) and Cr (0.04-9.7 wt.% Cr2O3), but have low Al (0.2-5.7 wt.% Al2O3). In the case of the P-15 kimberlite they display a range in compositions from andradite to schorlomite, with a low proportion of grossular (andradite(17.7-49.9)schorlomite(34.6-49.5)-grossular(3.7-22.8)-pyrope(1.9-10.4)). A few grains also contain significant chromium and represent a solid solution between schorlomite and uvarovite. The Ti-rich garnets in the KL-3 kimberlite, in contrast, are mostly schorlomitic (54.9?90.9 mol %) in composition. The Ti-rich garnets in the groundmass of these two kimberlites are intimately associated with chromian spinels, perhaps suggesting that the garnet formed through the replacement of spinel. From the textural evidence, it appears unlikely that the garnets could have originated through secondary alteration, but rather seem to have formed through a process in which early magmatic spinels have reacted with late circulating, residual fluids in the final stages of crystallization of the kimberlite magma. Raman spectroscopy provides evidence for low crystallinity in the spinels which is likely to be a result of their partial transformation into andradite during their reaction with a late-stage magmatic (kimberlitic) fluid. The close chemical association of these Ti-rich garnets in TiO2-FeO-CaO space with those reported from ultramafic lamprophyres (UML) is also consistent with results predicted by experimental studies, and possibly implies a genetic link between kimberlite and UML magmas. The occurrence of Ti-rich garnets of similar composition in the Swartruggens orangeite on the Kaapvaal craton in South Africa, as well as in other kimberlites with an orangeitic affinity (e.g. the P-15 kimberlite on the Eastern Dharwar craton in southern India), is inferred to be a reflection of the high Ca- and high Ti-, and the low Al-nature, of the parent magma (i.e. Group II kimberlites).
DS200512-0517
2005
Gudfinnasson, G.H.Keshav, S., Corgne, A., Gudfinnasson, G.H., Bizimis, M., McDonough, W.F., Fei, Y.Kimberlite petrogenesis: insights from clinopyroxene melt partitioning experiments at 6 GPa in the CaO MgO Al2O3 SiO2 CO2 system.Geochimica et Cosmochimica Acta, Vol. 69, 11, June 1, pp. 2829-2845.Africa, South AfricaGroup I, modeling
DS1998-0546
1998
Gudfinnson, G.H.Gudfinnson, G.H., Wood, B.J.Partitioning of trace elements between wadsleyite and ringwoodite, their solution mechanisms and effects...Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 549-50.GlobalPetrology - experimental
DS2001-0423
2001
Gudfinnson, G.H.Gudfinnson, G.H., Presnall, D.C.A pressure independent geothermometer for primitive mantle meltsJournal of Geophysical Research, Vol. 106, No. 8, pp. 16, 205-12.MantleGeothermometry
DS2003-0517
2003
Gudfinnsoon, G.H.Gudfinnsoon, G.H., Presnall, D.C.Continuous gradations among primary kimberlitic, carbonatitic, melititic and komatititic8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, AbstractSouth AfricaKimberlite petrogenesis
DS200412-0742
2003
Gudfinnsoon, G.H.Gudfinnsoon, G.H., Presnall, D.C.Continuous gradations among primary kimberlitic, carbonatitic, melititic and komatititic melts in equilibrium with garnet lherzo8 IKC Program, Session 7, AbstractAfrica, South AfricaKimberlite petrogenesis
DS200912-0805
2009
GudfinnssonWalter, M.J., Bulanova, G.P., Armstrong, L.S., Keshav, S., Blundy, Gudfinnsson, Lord, Lennie, Clark, GobboPrimary carbonatite melt from deeply subducted oceanic crust.Nature, Vol. 459, July 31, pp. 622-626.South America, Brazil, MantleMelting, geochemistry
DS200912-0272
2008
Gudfinnsson, G.Gudfinnsson, G., Keshav, S., Presnall, D.Water rich carbonatites at low pressures and kimberlites at high pressures.American Geological Union, Fall meeting Dec. 15-19, Eos Trans. Vol. 89, no. 53, meeting supplement, 1p. abstractMantleCarbonatite
DS200512-0374
2005
Gudfinnsson, G.H.Gudfinnsson, G.H., Presnall, D.C.The implications of different geotherms for the generation of carbonatites, kimberlites and melilitites.Abstract 1p., Geothermometry
DS200512-0375
2005
Gudfinnsson, G.H.Gudfinnsson, G.H., Presnall, D.C.Continuous gradations among primary carbonatitic, kimberlitic, melilititic, basaltic, picritic and komatiitic melts in equilibrium with garnet lherzolite at 3-8 GPa.Journal of Petrology, Vol. 46, 8, pp. 1645-1659.MantlePetrology - kimberlite, carbonatite
DS200512-0873
2005
Gudfinnsson, G.H.Presnall, D.C., Gudfinnsson, G.H.Carbonate rich melts in the oceanic low-velocity zone and deep mantle.Plates, Plumes, and Paradigms, pp. 207-216. ( total book 861p. $ 144.00)MantleCarbonate melts
DS200512-0874
2005
Gudfinnsson, G.H.Presnall, D.C., Gudfinnsson, G.H.MORB major element systematics: implications for melting models and mantle temperatures.Chapman Conference held in Scotland August 28-Sept. 1 2005, 1p. abstractMantle, IcelandMantle plume, geothermometry
DS200712-0532
2007
Gudfinnsson, G.H.Keshav, S., Gudfinnsson, G.H., Presnall, D.C.Precipitous drop in the carbonated peridotite solidus between 14-16 GPa: calcic carbonatites in the Earth's transition zone.Plates, Plumes, and Paradigms, 1p. abstract p. A479.MantleCarbonatite
DS201112-0515
2011
Gudfinnsson, G.H.Keshav, S., Gudfinnsson, G.H., Presnall, D.C.Melting phase relations of simplified carbonated peridotite at 12-26 GPa in the system CaO-MgO-SiO2-CO2 and CaO-MgO-Al2O3-Sio2-CO2: highly calcic magmas EarthJournal of Petrology, Vol. 51, pp. 2265-2291.MantleTransition zone of the Earth
DS201112-0827
2011
Gudfinnsson, G.H.Presnall, D.C., Gudfinnsson, G.H.Oceanic volcanism from the low-velocity zone - without mantle plumes.Journal of Petrology, Vol. 52, 7-8, pp. 1533-1546.MantleVolcanism
DS201412-0455
2014
Gudfinnsson, G.H.Keshav, S., Gudfinnsson, G.H.Melting phase equilibration temperatures of model carbonated peridotite from 8 to 12 Gpa in the system CaO-MgO-Al2O3-SiO2-CO2 and kimberlitic liquids in the Earth's upper mantle.American Mineralogist, Vol. 99, pp. 1119-1126.MantleMelting
DS202005-0742
2020
Gudfinnsson, G.H.Keshav, S., Corgne, A., Gudfinnsson, G.H., Fei, Y.Major and trace element partitioning between majoritic garnet, clinopyroxene, and carbon dioxide-rich liquid in model carbonated peridotite at 10 Gpa and interpretations of the element chemistry of majoritic garnet inclusions in diamonds from the subcontiLithos, Vol. 362-363, 11p. PdfSouth America, Brazil, Guineadiamond inclusions

Abstract: Experimentally determined major and trace element partition coefficients between majoritic garnet, clinopyroxene, and carbon dioxide-rich liquid are reported at 10 GPa and 1800 °C in a model carbonated peridotite composition in the system CaO-MgO-Al2O3-SiO2-CO2. Besides majoritic garnet, the liquid coexists with forsterite, orthopyroxene, and clinopyroxene, making melting phase relations invariant at fixed pressure and temperature conditions. Partition coefficients span a wide range of values - for instance, Sr, Nb, Ba, La, and Ce are highly incompatible in majoritic garnet, while Ca, Y, Nb, and Ho are moderately incompatible, and Lu, Si, Al, and Mg are compatible. Strong fractionation of light rare earth elements (e.g., La, Ce, Nd, Sm) and high field strength elements (e.g., Nb, Ta, Zr, Hf, Th) is seen between majoritic garnet and liquid. The experimentally determined partitioning values are used to calculate compositions of melts in equilibrium with majoritic garnet inclusions in diamonds from select localities in Brazil and Guinea. The calculated melts largely straddle those between documented carbonatites, kimberlites, and alkali basalts, low-degree mantle melting products from carbonated peridotite. This resemblance firmly suggests that majoritic garnet inclusions in diamonds from Brazil and Guinea can simply be interpreted as precipitates from such melts, thereby offering an alternative to the hypothesis that the element chemistry of such inclusions in diamonds can largely, and sometimes only, be ascribed to subducted oceanic crust, and further that, fusion of this crust may limit the terrestrial 'carbon recycling' at depths much beyond corresponding to those of Earth's transition zone.
DS201012-0235
2009
Gudlewski, B.Gilbertson, A., Gudlewski, B., Jhonson, M., Maltezos, G., Scherer, A., Shigley, J.Cutting diffraction gratings to improve dispersion ( 'fire') in diamonds. A new process of plasma eteching diffraction patterns on diamond facets.Gems & Gemology, Vol. 45, 4, Winter pp. 260-270.TechnologyDiamond cutting
DS1998-0547
1998
Gudminsson, A.Gudminsson, A.Magma chambers modeled as cavities explain the formation of rift zone central volcanoes and eruption.Journal of Geophysical Research, Vol. 103, No. 4, Apr. 10, pp. 7401-12GlobalVolcanoes, Rift zones - intrusion statistics
DS1992-0627
1992
Gudmundson, G.Gudmundson, G.Experimental re-equilibrium of the oxidation states of upper mantlegarnetsEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.335MantleExperimental petrology, Garnets
DS200512-0859
2005
Gudmundson, O.Pilidou, S., Priestly, K., Debayle, E., Gudmundson, O.Rayleigh wave tomography in the North Atlantic: high resolution images of the Iceland, Azores and Eifel mantle plumes.Lithos, Vol. 79, 3-4, pp. 453-474.Europe, IcelandTomography
DS200512-0589
2005
GudmundssonKumar, P.R., Kind, W., Hanka, K., Wylegalla, Ch., Reigber, X., Yuan, I., Woelbern, P., GudmundssonThe lithosphere-asthenosphere boundary in the North West Atlantic region.Earth and Planetary Science Letters, Vol. 236, pp. 249-257.EuropeBoundary
DS1990-0609
1990
Gudmundsson, A.Gudmundsson, A.Emplacement of dikes, sills and crustal magma chambers at divergent plateboundariesTectonophysics, Vol. 176, No. 3/4, May 10, pp, . 257-275GlobalMagma, Dike emplacement
DS1993-0591
1993
Gudmundsson, A.Gudmundsson, A.On the structure and formation of fracture zonesTerra Nova, Vol. 5, pp. 215-224Mid-Ocean RidgeStructure, Tectonics
DS1999-0275
1999
Gudmundsson, A.Gudmundsson, A.Post glacial crustal doming, stresses and fracture formation with application to Norway.Tectonophysics, Vol. 307, No. 3-4, June 30, pp. 407-NorwayTectonics
DS200512-0376
2005
Gudmundsson, A.Gudmundsson, A., Acocella, V., De Natale, G.The tectonics and physics of volcanoes.Journal of Volcanology and Geothermal Research, Vol. 144, 1-4, pp. 1-5.MantleVolcanoes
DS200712-0395
2006
Gudmundsson, A.Gudmundsson, A.How local stresses control magma chamber ruptures, dyke injections, and eruptions in composite volcanoes.Earth Science Reviews, Vol. 79, 1-2, Nov. pp. 1-31.MantleMagmatism
DS201510-1770
2015
Gudmundsson, A.Gudmundsson, A.Collapse-driven large eruptions.Journal of Volcanology and Geothermal Research, Vol 304, pp. 1-10.MantleMagmatism

Abstract: For a typical poroelastic shallow crustal magma chamber, about 0.1% of the mafic magma and about 4% of the felsic magma are erupted and/or injected during magma-chamber rupture. Magma chambers with volumes of the order of several tens to several hundred cubic kilometres, as are common, are thus sufficiently large to supply magma to small or moderate eruptions. For large eruptions, however, a much higher percentage of the magma volume must be squeezed out of the chamber. For an ordinary poroelastic chamber, the excess pressure in the chamber falls exponentially during the eruption. For a large eruption to be possible, however, the excess pressure must be essentially maintained until the very end of the eruption. Here I show that caldera collapse can maintain the excess pressure through forced magma-chamber volume reduction, in which case a resulting large eruption would be the consequence (not the cause) of the collapse. I also show that ring-fault dip partly controls the size and intensity (volumetric flow or effusion rate) of the eruption. If the ring-fault dips inward (a normal fault), the displacement is ‘stable’, the volumetric flow rate (intensity) remains essentially constant during the collapse, and the magma chamber remains active following the collapse. By contrast, if the ring-fault dips outward (a reverse fault), the displacement is ‘unstable’, the volumetric flow rate normally increases dramatically during the collapse, and the magma chamber may be entirely destroyed during the collapse.
DS200512-0894
2005
Gudmundsson, G.H.Raymond, M.J., Gudmundsson, G.H.On the relationship between surface and basal properties on glaciers, ice sheets, and ice streams.Journal of Geophysical Research, Vol. 110, B8, pp. B08411 10.1029/2005 JB003681TechnologyGeomorphology
DS200612-1139
2005
Gudmundsson, G.H.Raymond, M.J., Gudmundsson, G.H.On the relationship between surface and basal properties on glaciers, ice sheets and ice streams.Journal of Geophysical Research, Vol. 110, B8, BO8411.GlobalGeomorphology
DS1998-0548
1998
Gudmundsson, O.Gudmundsson, O., Sambridge, M.A regionalized upper mantle (RUM) seismic modelJournal of Geophysical Research, Vol. 103, No. 4, Apr. 10, pp. 7121-36.MantleGeophysics - seismic, Model
DS2000-0161
2000
Gudmundsson, O.Clitheroe, G., Gudmundsson, O., Kennett, B.L.N.The crustal thickness of AustraliaJournal of Geophysical Research, Vol. 105, No. 6, June 10, pp. 13697-AustraliaGeophysics
DS2003-0518
2003
Gudmundsson, O.Gudmundsson, O.The dense root of the Iceland crustEarth and Planetary Science Letters, Vol. 206, No. 3-4, pp. 427-40.IcelandMantle - tectonics
DS200412-0406
2004
Gudmundsson, O.Darbyshire, F.A., Larsen, T.B., Mosegaard, K., Dahl Jensen, T., Gudmundsson, O., Bach, T., Gregersen, S., PedeA first detailed look at the Greenland lithosphere and upper mantle; using Rayleigh wave tomography.Geophysical Journal International, Vol. 158, 1, pp. 267-286.Europe, GreenlandGeophysics - seismic
DS200512-0860
2004
Gudmundsson, O.Pilidou, SA., Priestley, K., Gudmundsson, O., Debayle, E.Upper mantle S-wave speed heterogeneity and anisotropy beneath the North Atlantic from regional surface wave tomography: the Iceland and Azores plumes.Geophysical Journal International, Vol. 159, 3, pp. 1057-1076.Europe, IcelandGeophysics - seismics
DS1984-0324
1984
Gudmunsddon, A.Gudmunsddon, A.Formation of dykes, feeder dykes and the intrusion of dikes from magmachambersBulletin. Volcanology, Vol. 47, No. 3, pp. 537-550GlobalDyke
DS1950-0134
1953
Guebelin, E.Guebelin, E.Inclusions as a Means of Gemstone IdentificationGemological Institute of America, Santa Monica, CA, GlobalKimberlite, Kimberley, Janlib, Gemology
DS1975-1040
1979
Guebelin, E.Guebelin, E.Internal World of GemstonesLondon: Newnes-butterworths, 234P.GlobalDiamond, Kimberley, Inclusions, Mineralogy
DS1960-1118
1969
Guebelin, E.J.Guebelin, E.J.Edelsteine. #1Zurich:, GlobalKimberlite, Kimberley, Janlib, Gemology
DS1970-0698
1973
Guebelin, E.J.Guebelin, E.J.Innenwelt der EdelsteineZurich: Abc-verlag, GlobalKimberlite, Kimberley, Janlib, Gemology
DS1970-0895
1974
Guebelin, E.J.Chudoba, K., Guebelin, E.J.Edelsteinkundliches HandbuchLeipzig: 1st. Edition 1896, GlobalKimberlite, Kimberley, Janlib, Gemology
DS1998-1162
1998
Gueddari, K.Piboule, M., Gueddari, K.Petrology and geochemistry of some unusual corundum bearing garnet pyroxenites Ronda lherzolitic MassifMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 1172-3.GlobalPetrography, geochemistry, CorunduM.
DS202103-0381
2021
Guedes, E.Giro, J.P., Almeida, J., Guedes, E., Bruno, H.Tectonic inheritances in rifts: the meaning of NNE lineaments in the continental rift of SE Brazil.Journal of South American Earth Sciences, Vol. 108, 103255. 17p. PdfSouth America, Brazillineaments, tectonics

Abstract: The effect of previous structures inheritance is known to be important in the development of tectonic rifts. A series of overlapping structures generally can be represented by lineaments marking the successive tectonic events. We studied the NNE structural lineaments corridor in the central region of the Ribeira Belt. We used a digital elevation model (DEM) and new and previous fieldwork data to investigate the structural control of such lineaments and their relevance for the Brazilian continental margin. Our results suggest that the NNE direction is a crustal weakness zone characterising corridors of intense ductile and brittle deformation which was recurrently reactivated. Aligned NNE Neoproterozoic-Ordovician ductile and brittle structures as foliations, shear zones, lithological boundaries, and fractures filled by pegmatitic veins coincide with the lineaments. During the Cretaceous rift, a transtensional sinistral regime generated NNE T-fractures filled by mafic dykes. In the Cenozoic, the NNE direction is represented by transfer and domino faults developed within a mega accommodation zone in an intracontinental rift system. Our results suggest that the NNE direction was active in this region throughout the Phanerozoic and has high relevance for the structural development of the continental margin of southeastern Brazil.
DS1970-0917
1974
Gueguen, Y.Green, H.W., Gueguen, Y.Origin of the Kimberlite Pipes by Upwelling in the Upper Mantle.Nature., Vol. 249, No. 5458, PP. 617-620.South Africa, West AfricaKimberlite Genesis
DS1980-0148
1980
Gueguen, Y.Green, H.W., Gueguen, Y.Deformation of Peridotite in the Mantle and Extraction by Kimberlite.Eos, Vol. 61, No. 46, P. 1156. (abstract.).United States, Colorado PlateauBlank
DS1983-0262
1983
Gueguen, Y.Green, H.W.II, Gueguen, Y.Deformation of Peridotite in the Mantle and Extraction by Kimberlite a Case History Documented by Fluid and Solid Precipitates in Olivine.Tectonophysics, Vol. 92, No. 1-3, PP. 71-92.AustraliaPetrography
DS1991-1471
1991
Gueguen, Y.Ruffet, C., Gueguen, Y., Darot, M.Rock conductivity and fractal nature of porosityTerra Nova, Vol. 3, No. 3, pp. 265-275GlobalGeophysics, Cole and Cole
DS201910-2299
2019
Guelius, D.Shu, Q., Brey, G., Fichtner, C., Guelius, D.Nature and mechanisms of mantle metasomatism.Goldschmidt2019, 1p. AbstractMantlemetasomatism

Abstract: The interaction between hydrous fluids and melts with dry pre-existing mantle rocks alters the physocochemical porperties of the deep lithosphere. Here we present new insight into mantle metasomatism based on petrology, geochemistry, and Rare Earth Element (REE) distribution modelling using mantle xenoliths from various eruption centres in the Cenozoic Tariat volcanic field, Mongolia. These centres include the Horgo, Tsagan, Zala, Haer and Shavaryn-Tsaram lava flows that vary in composition and age between alkali basalts to trachybasalts to tephrite basanites and 4 ka to 1.5 Ma, respectively. Our sample suite contains xenolith from the lower crust and underlying mantle with a size range of individual xenoliths between 3 cm and 8 cm. Based on the clinopyroxene REE concentration pattern, the investigated xenoliths can be divided in two groups, characterized by LREE depletion (Group 1) and enrichment (Group 2) relative to primitive mantle. Group 1 xenoliths display well-preserved deformation textures and are considered to represent the sub-continental lithosphere prior to Cenozoic rejuvenation. In contrast, Group 2 samples are marked by partial annealing of pre-existing textures. REE distribution modelling between clinopyroxene and inferred chemically enriched basaltic melt suggests that the observed REE pattern do not reconcile with a simple mixing model but reflect chromatographic fractionation during reactive melt flow. In addition, the clinopyroxene core-rim REE variation in some of the xenoliths suggests interaction with at least one other melt of distinct chemical composition.
DS201907-1576
2019
Guenko, A.A.Sobolev, A.V., Asafov, E., Arndt, N., Portnyagin, M., Guenko, A.A., Batanova, G., Garbe-Schonberg, D., Wilson, A.H., Byerly, G., Batanova, V.Deep hydrous mantle reservoir provides evidence for crustal recycling before 3.3 billion years ago.Nature, 32p. Pdf availableMantlewater

Abstract: H2O strongly influences physical properties of the mantle and its ability to melt or convect and can trace recycling of surface reservoirs down to the deep mantle1,2. This makes knowledge of water content in the Earth's interior and its evolution through time crucial to understanding global geodynamics. Komatiites (MgO-rich ultramafic magmas) result from high-degree mantle melting at high pressures3 and thus are excellent probes of H2O contents in the deep mantle. A significant excess of H2O over elements of similar geochemical behavior during mantle melting (e.g. Ce) was recently found in melt inclusions in the most Mg-rich olivine in 2.7 Ga old komatiites from Canada4 and Zimbabwe5. These data were taken as evidence for a deep hydrated mantle reservoir, probably the transition zone, in the Neoarchean time. In this paper we confirm the mantle source of this H2O by measurement of deuterium to hydrogen ratios in these melt inclusions and present similar data for 3.3 Ga old komatiites from the Barberton Greenstone Belt. Using hydrogen isotopes, we show that the mantle sources of these melts contained excess H2O which implies that a deep mantle hydrated reservoir has been present in the Earth's interior at least since the Paleoarchean. The reconstructed initial hydrogen isotope composition of komatiites is significantly more depleted in deuterium than all surface reservoirs and typical mantle but resembles that in dehydrated subducted slabs. Together with a significant excess of chlorine and a temporal trend of Pb/Ce in the mantle sources of komatiites, these results argue that lithosphere recycling into the deep mantle, arguably via subduction, started before 3.3 Ga. (a un-reviewed version of the manuscript accepted for publication in Nature magazine).
DS201312-0579
2013
Guenther, D.Martin, L.H.J., Schmidt, M.W., Mattsson, H.B., Guenther, D.Element partitioning between immiscible carbonatite and silicate melts for dry and H2O bearing systems at 1-3 Gpa.Journal of Petrology, Vol. 54, pp. 2301-2338.MantleCarbonatite
DS202112-1931
2021
Guentthner, W.R.Kaempfer, K.M., Guentthner, W.R., Pearson, D.R.Proterozoic to Phanerozoic tectonism in southwestern Montana basement and ranges constrained by low temperature thermochronometric data.Tectonics, Vol. 40, 11 22021TC006744United States, Montanageothermometry

Abstract: Crystalline basement rocks of southwestern Montana have been subjected to multiple tectonothermal events since ?3.3 Ga: the Paleoproterozoic Big Sky/Great Falls orogeny, Mesoproterozoic extension associated with Belt-Purcell basin formation, Neoproterozoic extension related to Rodinia rifting, and the late Phanerozoic Sevier-Laramide orogeny. We investigated the long-term (>1 Ga), low-temperature (erosion/burial within 10 km of the surface) thermal histories of these tectonic events with zircon and apatite (U-Th)/He thermochronology. Data were collected across nine sample localities (n = 55 zircon and n = 26 apatite aliquots) in the northern and southern Madison ranges, the Blacktail-Snowcrest arch, and the Tobacco Root uplift. Our zircon (U-Th)/He data show negative trends between single aliquot date and effective uranium (a radiation damage proxy), which we interpreted with a thermal history model that considers the damage-He diffusivity relationship in zircon. Our model results for these basement ranges show substantial cooling from temperatures above 400°C to near surface conditions between 800 and 510 Ma. Subsequent Phanerozoic exhumation culminated by ?75 Ma. Late Phanerozoic cooling is coincident with along-strike Sevier belt thin-skinned thrusting in southeastern Idaho, and older than exhumation in basement-involved uplifts of the Wyoming Laramide province. Our long-term, low-temperature thermal record for these southwestern Montana basement ranges shows that: (a) these basement blocks have experienced multiple episodes of upper crustal exhumation and burial since Archean time, possibly influencing Phanerozoic thrust architecture and (b) the late Phanerozoic thick-skinned thrusting recorded by these rocks is among the earliest thermochronologic records of Laramide basement-involved shortening and was concomitant with Sevier belt thin-skinned thrusting.
DS200612-0509
2006
Guerin, T.F.Guerin, T.F.A survey of sustainable development initiatives in the Australian mining and minerals industry.Minerals & Energy - Raw Materials Report, Vol. 20, 3-4, March pp. 11-44.AustraliaEconomics - sustainable resources
DS201803-0435
2007
Guerra, W.J.Battilani, G.A., Newton, S.G., Guerra, W.J.The occurrence of microdiamonds in Mesoproterozoic Chapada Diamantin a intrusive rocks: bahia, Brazil.Anais da Academia Brasileira de Ciencas, Vol. 79, pp. 321-332.South America, Brazilmicrodiamonds

Abstract: The origin of diamonds from Serra do Espinhaço in Diamantina region (State of Minas Gerais) and in Chapada Diamantina, Lençóis region (State of Bahia) remains uncertain, even taking into account the ample research carried out during the last decades. The lack of typical satellite minerals in both districts makes a kimberlitic source for these diamonds uncertain. In mid 18th century the occurrence of a metamorphosed igneous rock composed of martite, sericite and tourmaline was described in Diamantina region and named hematitic phyllite, considered by some researchers as a possible diamond source. Similar rocks were found in Lençóis and examined petrographically and their heavy mineral concentration was investigated by means of scanning electron microscopy (SEM). Petrographic analyses indicated an igneous origin for these rocks and SEM analyses showed the discovery of microdiamonds. Geochronological studies using the Ar/Ar technique in muscovites yielded minimum ages of 1515+/-3 Ma, which may correlate with 1710+/-12 Ma from U-Pb method in igneous zircons from the hematitic phyllites. Both rock types also have the same mineral and chemical composition which leads to the conclusion that the intrusive rocks were protolith of the hematitic phyllites. This first discovery of microdiamonds in intrusive rocks opens the possibility of new investigation models for diamond mineralization in Brazilian Proterozoic terrains.
DS1995-0819
1995
Guerrero, J.Hoorn, C., Guerrero, J., Sarmiento, G.A., Lorente, M.A.Andean tectonics as a cause for changing drainage patterns in Miocene northern South America.Geology, Vol. 23, No. 3, March pp. 237-240.Guyana Shield, VenezuelaTectonics, Geomorphology
DS1989-0556
1989
Guerrot, C.Guerrot, C., Peucat, J.J., Capdevila, R., Dosso, L.Archean protoliths within early Proterozoic granulitic crust of the west European Hercynian belt: possible relics of the west African cratonGeology, Vol. 17, No. 3, March pp. 241-244West AfricaCraton, Proterozoic
DS1997-0182
1997
Guerrot, C.Chauvet, A., Guerrot, C., et al.Geochronology of the paleoproterozoic granites of the Rio Itapicuru greenstone belt, Bahia, Brasil. (in French)C.r. Academy Of Science Paris, Vol. 324, No. 11a, pp. 293-300BrazilGreenstone belt, Geochronology
DS1997-0183
1997
Guerrot, C.Chavet, A., De Silva, F.C. Alves, Guerrot, C.Structural evolution of the Paleoproterozoic Rio Itapicuru granite greenstone belt, Role of synkinematicPrecambrian Research, Vol. 84, No. 3-4, Oct. pp. 139-162Brazil, BahiaTectonics - regional, Rio Itapicuru Belt
DS1920-0232
1925
Guest, H.M.Guest, H.M.Some Reminiscences of Sixty Years AgoKlerksdorp: Privately Publishing Guest., 24P.South Africa, Cape ProvinceHistory, Biography, Kimberley
DS1995-0693
1995
Guest, P.Guest, P.The diamond opportunity in Minas Gerais, BrasilRandol at Vancouver '94, pp. 51-53.BrazilDiamond exploration
DS200512-0377
2004
Guest, R.Guest, R.The shackled continent: power, corruption and African lives.Smithsonian , 288p. Sept. $ 18.00AfricaBook - history, economics
DS1981-0196
1981
Guetat, Z.Guetat, Z.Etude Gravimetrique de la Bordure Occidentale du Craton Ouest Africain.Montpellier: University Des Sciences Et Tech. Du Languedoc., West Africa, GuineaGravity, Geophysics, Tectonics
DS1859-0012
1756
Guettard, J.E.Guettard, J.E.Memoire dans Lequel on Compare le Canada and la Suisse Par Rapport a Ses Mineraux.Academy of Science Paris HIST. MEMOIRES 1752, MEMOIR PP. 189-220; HISTOIRE PP. 12-16.Canada, QuebecGemology
DS200412-0006
2004
Guevara, M.Agrawal, S., Guevara, M., Verma, S.P.Discriminate analysis applied to establish major element field boundaries for tectonic varieties of basic rocks.International Geology Review, Vol. 46, 7, pp. 575-594.TechnologyGeochemistry - not specific to diamonds
DS1991-0623
1991
Guex, J.Guex, J.Biochronological correlationsSpringer-Verlag, 272p. approx. $ 70.00 United StatesGlobalStratigraphy, Book-ad
DS200812-0917
2007
Gueydan, F.Precigout, J., Gueydan, F., Gapais, D., Garrido, C.J., Eassaifi, A.Strain localization in the subcontinental mantle ?? a ductile alternative to the brittle mantle.Tectonophysics, Vol. 445, 3-4, pp. 318-336.MantleSubduction
DS200912-0598
2009
Gueydan, F.Precigout, J., Gueydan, F.Mantle weakening and strain localization: implications for the long term strength of the continental lithosphere.Geology, Vol. 37, 2, pp. 147-150.MantleDelamination
DS201506-0271
2015
Gueydan, F.Gueydan, F., Pitra, P., Afiri, A., Poujol, M., Essaifi, A., Paquette, J-L.Oligo-Miocene thinning of the Beni Bousera peridotites and their Variscan crustal host rocks, Internal Rif, Morocco.Tectonics, Vol. 34, pp.1244-1268.Africa, MoroccoPeridotite
DS201805-0989
2018
Gueydan, F.Vincente de Gouveia, S., Besse, J., Frizon de Lamotte, D., Greff-Lefftz, M., Lescanne, M., Gueydan, F., Leparmentier, F.Evidence of hot spot paths below Arabia and the Horn of Africa and consequences on the Red Sea opening.Earth Planetary Science Letters, Vol. 487, pp. 210-220.Africatectonics

Abstract: Rifts are often associated with ancient traces of hotspots, which are supposed to participate to the weakening of the lithosphere. We investigated the expected past trajectories followed by three hotspots (Afar, East-Africa and Lake-Victoria) located around the Red Sea. We used a hotspot reference frame to compute their location with respect to time, which is then compared to mantle tomography interpretations and geological features. Their tracks are frequently situated under continental crust, which is known to strongly filter plume activity. We looked for surface markers of their putative ancient existence, such as volcanism typology, doming, and heat-flow data from petroleum wells. Surface activity of the East-Africa hotspot is supported at 110 Ma, 90 Ma and 30 Ma by uplift, volcanic activity and rare gas isotopic signatures, reminiscent of a deep plume origin. The analysis of heat-flow data from petroleum wells under the Arabian plate shows a thermal anomaly that may correspond to the past impact of the Afar hotspot. According to derived hotspot trajectories, the Afar hotspot, situated (at 32 Ma) 1000 km north-east of the Ethiopian-Yemen traps, was probably too far away to be accountable for them. The trigger of the flood basalts would likely be linked to the East-Africa hotspot. The Lake-Victoria hotspot activity appears to have been more recent, attested only by Cenozoic volcanism in an uplifted area. Structural and thermal weakening of the lithosphere may have played a major role in the location of the rift systems. The Gulf of Aden is located on inherited Mesozoic extensional basins between two weak zones, the extremity of the Carlsberg Ridge and the present Afar triangle, previously impacted by the East-Africa hotspot. The Red Sea may have opened in the context of extension linked to Neo-Tethys slab-pull, along the track followed by the East Africa hotspot, suggesting an inherited thermal weakening.
DS201901-0010
2018
Gueydan, F.Brun, J-P., Sokoutis, D., Tirel, C., Gueydan, F., Beslier, M-O.Crustal versus mantle core complexes.Tectonophysics, Vol. 746, pp. 22-45.Mantlegeodynamics

Abstract: Deep crustal and mantle rocks are exhumed in core complex mode of extension in three types of structures: metamorphic core complexes, oceanic core complexes and magma poor passive margins. Using available analogue and numerical models and their comparison with natural examples, the present paper reviews the mechanical processes involved in these different types of extensional setting. Three main aspects are considered: i) the primary role of lithosphere rheology, ii) the lithosphere-scale patterns of progressive deformation that lead to the exhumation of deep metamorphic or mantle rocks and iii) the initiation and development of detachment zones. Crustal core complexes develop in continental lithospheres whose Moho temperature is higher than 750 °C with “upper crust-dominated” strength profiles. Contrary to what is commonly believed, it is argued from analogue and numerical models that detachments that accommodate exhumation of core complexes do not initiate at the onset of extension but in the course of progressive extension when the exhuming ductile crust reaches the surface. In models, convex upward detachments result from a rolling hinge process. Mantle core complexes develop in either the oceanic lithosphere, at slow and ultra-slow spreading ridges, or in continental lithospheres, whose initial Moho temperature is lower than 750 °C, with “sub-Moho mantle-dominated” strength profiles. It is argued that the mechanism of mantle exhumation at passive margins is a nearly symmetrical necking process at lithosphere scale without major and permanent detachment, except if strong strain localization could occur in the lithosphere mantle. Distributed crustal extension, by upper crust faulting above a décollement along the ductile crust increases toward the rift axis up to crustal breakup. Mantle rocks exhume in the zone of crustal breakup accommodated by conjugate mantle shear zones that migrate with the rift axis, during increasing extension.
DS1988-0127
1988
Guezlane, M.Chorowicz, J., Guezlane, M., Rudant, J., Vidal, G.Use of MOMS-1 dat a for geological mapping of the Aswa lineament(East African Rift)National Technical Information Service, In ESA Proceedings 4th. International Colloquium in Spectral Signatures in Remote, N89 10382/4 4p. April 1988 Entire Conference $ 49.95TanzaniaTectonics, Remote Sensing
DS1989-0360
1989
Gufan, Y.M.Dmitriev, V.P., Rochal, S.B., Gufan, Y.M., Toledano, P.Reconstructive transitions between ordered phases -the Martensitic FCC-HCP and the graphite diamondtransitionsPhys. Rev. L., Vol. 62, No. 2, May 22, pp. 2495-2498GlobalDiamond morphology, Graphite-diamond
DS200512-0762
2005
Guffett, B.A.Nakagawa, T., Guffett, B.A.Mass transport mechanism between the upper and lower mantle in numerical simulations of thermochemical mantle convection with multicomponent phase changes.Earth and Planetary Science Letters, Vol. 230, 1-2, pp. 11-27.MantleGeothermometry
DS1995-1624
1995
Guguen, Y.Ruffet, C., Darot, M., Guguen, Y.Surface conductivity in rocks: a reviewSurveys in Geophysics, Vol. 16, pp. 83-105.GlobalGeophysics - conductivity, Rock interfaces, experimental
DS1995-1716
1995
Guguere, E.Sharma, K.N.M., Guguere, E., Cimon, J., Madore, L.Les roches ultramafiques dans le Granville de l'Outaoais... contexte tectonique et potential mineralQuebec Department of Mines, Pro 95-08, 6p.QuebecUltramafics
DS1995-1717
1995
Guguere, E.Sharma, K.N.M., Guguere, E., Cimon, J., Madore, L.Les roches ultramafiques dans le Grenville de l'Outaoais... contexte tectonique et potential mineralQuebec Department of Mines, Pro 95-08, 6p.QuebecUltramafics
DS201312-0343
2012
Guha, A.Guha, A., Ananth Rao, D., Ravi, S., Kumar, K.V., Dhananjaya Rao, E.N.Analysis of the potential of kimberlite rock spectra as spectral end member using samples from Narayanpet kimberlite field, Andhra Pradesh.Current Science, Vol. 103, 9, Nov. 10, pp. 1096-1104.IndiaDeposit - Narayanpet
DS201512-1922
2015
Guha, A.Guha, A., Kumar, K.V., Ravi, S., Dhananjaya Rao, E.N.Reflectance spectroscopy of kimberlites - in parts of Dharwar Craton, India.Arabian Journal of Geosciences, Vol. 8, no. 11, pp. 9373-9388.IndiaDeposit - Narayanpet

Abstract: In the present study, an attempt was made to analyse the reflectance spectra of kimberlites to evaluate its potential as key in remote sensing based spatial mapping. The spectral profiles of kimberlite samples were collected within the visible-near infrared-shortwave infrared (VNIR-SWIR) electromagnetic domain. In this regard, we analysed the reflectance spectra of three kimberlite pipes (having variable mineralogy) of Narayanpet kimberlite field (NKF) based on the comparative analysis of spectral features of kimberlite samples with the spectral features of their dominant constituent minerals. The relative abundances of each of the constituent minerals were confirmed using semiquantitative mineralogical data from X-ray diffraction analysis. This was supplemented with petrographical data as reference. We found that the absorption features imprinted in the reflectance spectra of kimberlites were mineralogically sensitive. These spectral features were imprinted by spectral features of serpentine, olivine, and calcite depending on the relative dominance of these minerals in kimberlites. With regard to understand the spectral behaviour of weathered residue of kimberlite for targeting buried kimberlite, we also attempted a comparative analysis of spectral profiles of in-situ soil developed above the pipes with the spectra of respective kimberlites in NKF area. While comparing aforementioned spectra, it was observed that the spectral signatures of NKF kimberlites were broadly translated to the in-situ soil. Further, we compared the spectral profiles of selected NKF kimberlites with the spectra of three distinct kimberlite pipes of Wajrakarur kimberlite field (WKF) characterised with similar mineralogy with respect to the selected NKF pipes. Relative dominance of constituent minerals (i.e., serpentine, olivine, calcite, etc.) in these pipes was taken as reference to identify the mineralogical similarity of the pipes of both the field. It was observed that the spectral profiles of NKF and WKF kimberlites were highly correlated with regard to wavelength of diagnostic absorption features. Finally, we also made an attempt to understand the effect of spectral mixing, in spectral separation of kimberlites and associated granite-granodiorite gneiss (i.e., Dharwar Gneiss). It was seen that the spectral contrast of kimberlite and gneiss was dependent on the relative size of the pipe with respect to pixel or ground sampling diameter of spectral data acquisition. Study confirmed the diagnostic nature of reflectance spectra of pipes along with their mineralogical sensitiveness and spatial integrity. It also highlighted how spectral mixing can influence the spectral feature based remote detection of kimberlites.
DS202006-0930
2020
Guha, A.Kumar, S., Pal, S.K., Guha, A.Very low frequency electromagnetic ( VLF-EM) study over Wajrakakarur kimberlite pipe 6 in eastern Dharwar craton, India.Journal of Earth System Science, Vol. 129, 1, 102 10p. PdfIndiadeposit - Pipe 6

Abstract: The Wajrakarur kimberlite Pipe 6 in Eastern Dharwar Craton, is hardly explored using latest ground-based geophysical techniques. The present study uses the Very Low Frequency Electromagnetic (VLF-EM) method for understanding the aerial extension, depth and geometry of the kimberlite pipe. The VLF-EM data have been analyzed using Fraser filtering of in-phase component, 3D Euler deconvolution of Fraser filtered in-phase data, radially average power spectrum (RAPS) of VLF data (raw data) and 2D inversion of VLF data (raw data). The Fraser filtered in-phase grid anomaly map has witnessed as an effective tool for mapping extension of the kimberlite pipe. The maxima of Fraser filtered in-phase component has been observed as a key parameter to delineate the conducting bodies. The high apparent current density in Karous-Hjelt (K-H) pseudo section locate relatively conducting body possibly associated with kimberlite pipe. Two depth interfaces at about 15 and 32 m have been delineated using RAPS. 3D Euler solution indicate dyke-like structure associated with kimberlite pipe having depth solutions ranging from 6 to 40 m with mode of depth 17 m in the study area. 2D resistivity sections indicate that causative bodies are in the depth range of 15-50 m. The results of VLF-EM study are well validated using geological borehole data over the study area reported by Geological Survey of India.
DS202107-1101
2018
Guha, A.Guha, A., Rani, K., Varma, C.B., Sarwate, N.K., Sharma, N., Mukherjee, A., Kumar, K.V., Pal, S.K., Saw, A.K., Jha, S.K.Identification of potential zones for kimberlite exploration - an Earth observation approach. ChhatarpurThe International Achives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol. XLII-5 12p. PdfIndia, Madhya PradeshASTER, lineament

Abstract: In the present study, we have prepared the thematic evidence layers for identifying the potential zones of kimberlite emplacement in parts of Chhatarpur district, Madhya Pradesh. These thematic layers or evidence layers are geological structure, alteration zones, lineament density, surface alteration and geomorphic anomaly and these layers are prepared from the remote sensing data. As orientation of the geological structures (i.e fault system) and their density have the major role in the emplacement of kimberlite; both of these evidence layers are integrated using "AND" Boolean Logical Operator. On the other hand, two evidential layers regarded as the proxy to indicate the "surface expressions on kimberlite (i.e. alteration zones and geomorphic anomaly) are combined using "OR" operator as either of these two surface expression is indicative of kimberlite. Consequently, conjugate evidence layers on the surface expressions of kimberlite are integrated with the causative evidence layers of kimberlite emplacement using "AND" operator to identify the potential zones of diamond occurrences. Potential zones of kimberlite are overlaid on the residual gravity anomaly map derived from space-based gravity model of European Improved Gravity of Earth by New Technique (EIGEN6C4) to relate potential zones of kimberlite with the similar structural alignment (delineated in the residual gravity map) of known occurrence of kimberlite. We also have carried out indicator mineral survey around these potential zones and some of the kimberlite specific indicator minerals are identified in the stream sediments within these potential zones.
DS200412-0328
2004
Guha, D.B.Choudhuri, A.R., Guha, D.B.Evolution of the Great Boundary Fault: a re-evaluation.Journal Geological Society of India, Vol. 64, 1, pp. 21-31.IndiaTectonics
DS2002-0851
2002
Guhin, S.S.King, J.M., Shigley, J.E., Guhin, S.S., Gelb, T.H., Hall, M.Characterization and grading of natural colour pink diamondsGems & Gemology, Vol. 38, Summer, pp. 128-147.Australia, India, Brazil, South AfricaDiamonds - pink ( database of 1500 ), Notable - list ( more than 9 cts each)
DS2002-0852
2002
Guhin, S.S.King, J.M., Shigley, J.E., Guhin, S.S., Gelb, T.H., Hall, M.Box A: understanding the relationship of pink and "red" diamonds in GIA colour grading system.Gems & Gemology, Vol. 38, Summer, pp. 134-140.GlobalDiamonds - pink, red
DS200512-0532
2005
Guhin, S.S.King, J.M., Shigley, J.E., Gelb, T.H., Guhin, S.S., Hall, M., Wang, W.Characterization and grading of natural colour yellow diamonds.Gems & Gemology, Vol. 41, 2, Summer pp. 88-115.GlobalHistory, genesis, origin, cut
DS200512-0378
2005
Gui, F.Gui, F., Fan, W., Wang, Y.Petrogenesis and tectonic implications of Early Cretaceous high K calc alkaline volcanic rocks in the Laiyang Basin of the Sulu Belt, eastern China.The Island Arc, Vol. 14, 2, June pp. 69-90.ChinaUHP
DS1997-0454
1997
Guiard, R.Guiard, R., Bosworth, W.Senonian basin inversion and rejuvenation of rifting in Africa and Arabia:synthesis and implications to plateTectonophysics, Vol. 282, No. 1-4, Dec. 15, pp. 39-82.Africa, ArabiaBasin, Tectonics
DS201909-2044
2019
Guice, G.L.Guice, G.L.Origin and geodynamic significance of Archean ultramafic-mafic complexes in the North Atlantic and Kaapvaal cratons.Phd. Thesis Cardiff University, 315p. PdfEurope, Scotland, Africa, South Africacratons

Abstract: The physical manifestations of plate tectonics on the modern Earth are relatively well-understood, but the nature and timing of its onset remains enigmatic, with the geodynamic regime(s) that operated during the Archaean hotly debated. This absence of a consistent geodynamic framework within which regional-scale observations can be placed limits our understanding of Archaean assemblages and associated mineral deposits. To engage with the Archaean geodynamics discussion, this thesis focuses on ultramafic-mafic complexes in the Lewisian Gneiss Complex (LGC) of the North Atlantic Craton and Johannesburg Dome of the Kaapvaal Craton. Globally, such complexes have been the subject of wide-ranging interpretations that have disparate implications for Archaean geodynamic regimes. Throughout this thesis, it is demonstrated that confidently constraining element mobility is of paramount importance when aiming to constrain the origin of Archaean ultramafic rocks, with a variety of geochemical proxies shown to be susceptible to element mobility. Notably, high field strength element anomalies - a geochemical proxy commonly used to fingerprint subduction-related magmatism - are here shown to be highly susceptible to element mobility, with the role of subduction as an Archaean geodynamic process potentially overestimated as a result. Such mobility can, however, be constrained and a primary geochemistry obtained using the integrated approach utilised here, whereby detailed petrography, bulk-rock geochemistry and mineral chemistry are examined using the context provided by rigorous field geology. Using this approach, the ultramafic-mafic complexes in the LGC are here interpreted as recording two temporally and petrogenetically distinct phases of Archaean magmatism. One group of complexes likely represents an early ultramafic-mafic crust that pre-dates the tonalite-trondhjemite-granodiorite (TTG) magmas, while a second group of complexes are interpreted as representing several layered intrusions that were emplaced into TTG. The ultramafic-mafic complexes in the Johannesburg Dome are considered to represent intrusive and extrusive remnants of an Archaean greenstone belt, contradicting a recently proposed hypothesis whereby the complexes are interpreted as fragments of an Archaean ophiolite. When combined with similar opposition to other proposed Archaean ophiolite occurrences in other cratons, this contradiction is potentially significant to the Archaean geodynamics debate, raising questions as to the validity of a > 3.6 Ga onset for modern-style plate tectonics.
DS202002-0191
2019
Guice, G.L.Guice, G.L.Origin and geodynamic significance of ultramafic- mafic complexes in the North Atlantic and Kaapvaal cratons.Thesis, Phd Cardiff University, 315p. PdfEurope, Africa, South Africacraton
DS2003-0197
2003
Guichet, X.Callot, J.P., Guichet, X.Rock texture and magnetic lineation in dykes: a simple analytical modelTectonophysics, Vol. 366, 3-4, pp. 207-222.GlobalGeophysics - magnetics
DS200412-0254
2003
Guichet, X.Callot, J.P., Guichet, X.Rock texture and magnetic lineation in dykes: a simple analytical model.Tectonophysics, Vol. 366, 3-4, pp. 207-222.TechnologyGeophysics - magnetics
DS201712-2669
2017
Guidi, M.Agrosi, G., Tempestra, G., Della Ventura, G., Guidi, M., Hutchison, M., Nimis, P., Nestola, F.Non-destructive in situ study of plastic deformations in diamonds: x-ray diffraction topography and micro-FTIR mapping of two super deep diamond crystals from Sao Luiz ( Juina, Brazil).Crystals, Vol. 7, #233South America, Brazildeposit - Juina

Abstract: Diamonds from Juina, Brazil, are well-known examples of superdeep diamond crystals formed under sublithospheric conditions and evidence would indicate their origins lie as deep as the Earth's mantle transition zone and the Lower Mantle. Detailed characterization of these minerals and of inclusions trapped within them may thus provide precious minero-petrogenetic information on their growth history in these inaccessible environments. With the aim of studying non-destructively the structural defects in the entire crystalline volume, two diamond samples from this locality, labelled JUc4 and BZ270, respectively, were studied in transmission mode by means of X-ray Diffraction Topography (XRDT) and micro Fourier Transform InfraRed Spectroscopy (µFTIR). The combined use of these methods shows a good fit between the mapping of spatial distribution of extended defects observed on the topographic images and the µFTIR maps corresponding to the concentration of N and H point defects. The results obtained show that both samples are affected by plastic deformation. In particular, BZ270 shows a lower content of nitrogen and higher deformation, and actually consists of different, slightly misoriented grains that contain sub-grains with a rounded-elongated shape. These features are commonly associated with deformation processes by solid-state diffusion creep under high pressure and high temperature.
DS201511-1838
2007
Guidolin, M.Guidolin, M., La Ferrara, E.Diamonds are forever, war is not: is conflict bad for private firms?The American Economic Review, Vol. 97, 5, pp. 1978-1993.GlobalEconomics

Abstract: This paper studies the relationship between civil war and the value of firms in a poor, resource abundant country using microeconomic data for Angola. We focus on diamond mining firms and conduct an event study on the sudden end of the conflict, marked by the death of the rebel movement leader in 2002. We find that the stock market perceived this event as “bad news” rather than "good news" for companies holding concessions in Angola, as their abnormal returns declined by 4 percentage points. The event had no effect on a control portfolio of otherwise similar diamond mining companies. This finding is corroborated by other events and by the adoption of alternative methodologies. We interpret our findings in the light of conflict-generated entry barriers, government bargaining power and transparency in the licensing process.
DS1989-0478
1989
Guidotti, C.V.Geiger, C.A., Guidotti, C.V.Precambrian metamorphism in the southern Lake Superior region and its bearing on crustal evolutionGeoscience Wisconsin, Vol. 13, July pp. 1-33Minnesota, Wisconsin, Michigan, MidcontinentTectonics, Crustal evolution
DS200612-0040
2006
Guidry, M.Arvidson, R.S., Mackenzie, F.T., Guidry, M.MAGic: a Phanerozoic model for the geochemical cycling of major rock forming components.American Journal of Science, Vol. 306, 3, pp. 135-190.TechnologyComputer program - MAGic, geochemistry
DS201412-0336
2014
Guignard, J.Hammouda, T., Chantel, J., Manthilake, G., Guignard, J., Crichton, W.Hot mantle geotherms stabilize calcic carbonatite magmas up to the surface.Geology, Vol. 42, no. 10, pp. 911-914.MantleCarbonatite
DS202012-2206
2020
Guignard, J.Borisova, A.Y., Bindeman, I.N., Toplis, M.J., Zagrtdenov, N.R., Guignard, J., Safonov, O.G., Bychkov, A.Y., Shcheka, S., Melnik, O.E., Marcelli, M., Fehrenbach, J.Zircon survival in shallow asthenosphere and deep lithosphere.American Mineralogist, Vol. 105, pp. 1662-1671. pdfMantlemelting

Abstract: Zircon is the most frequently used mineral for dating terrestrial and extraterrestrial rocks. However, the system of zircon in mafic/ultramafic melts has been rarely explored experimentally and most existing models based on the felsic, intermediate and/or synthetic systems are probably not applicable for prediction of zircon survival in terrestrial shallow asthenosphere. In order to determine the zircon stability in such natural systems, we have performed high-temperature experiments of zircon dissolution in natural mid-ocean ridge basaltic and synthetic haplobasaltic melts coupled with in situ electron probe microanalyses of the experimental products at high current. Taking into account the secondary fluorescence effect in zircon glass pairs during electron microprobe analysis, we have calculated zirconium diffusion coefficient necessary to predict zircon survival in asthenospheric melts of tholeiitic basalt composition. The data imply that typical 100 micron zircons dissolve rapidly (in 10 hours) and congruently upon the reaction with basaltic melt at mantle pressures. We observed incongruent (to crystal ZrO2 and SiO2 in melt) dissolution of zircon in natural mid-ocean ridge basaltic melt at low pressures and in haplobasaltic melt at elevated pressure. Our experimental data raise questions about the origin of zircons in mafic and ultramafic rocks, in particular, in shallow oceanic asthenosphere and deep lithosphere, as well as the meaning of the zircon-based ages estimated from the composition of these minerals. Large size zircon megacrysts in kimberlites, peridotites, alkali basalts and other magmas suggest the fast transport and short interaction between zircon and melt.The origin of zircon megacrysts is likely related to metasomatic addition of Zr into mantle as any mantle melting episode should obliterate them.
DS2001-0030
2001
Guignot, N.Andrault, D., Bolfan-Casanova, N., Guignot, N.Equation of state of lower mantle ( Al Fe MgSiO3) perovskiteEarth and Planetary Science Letters, Vol. 193, No. 3-4, pp.501-8.MantleGeochemistry, Perovskite
DS2002-0043
2002
Guignot, N.Andrault, D., Bolfan-Casanova, N., Guignot, N.Effect of aluminum on lower mantle mineralogy18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.76.MantleUHP mineralogy - perovskite
DS200612-1077
2006
Guignot, N.Perrillat, J.P., Ricolleau, A., Daniel, I., Fiquet, G., Mezouar, M., Guignot, N., Cardon, H.Phase transformations of subducted basaltic crust in the upmost lower mantle.Physics of the Earth and Planetary Interiors, Vol. 157, 1-2, pp. 139-149.MantleUHP, subduction
DS200712-0353
2006
Guignot, N.Gautron, L., Greaux, S., Andrault, D., Bolfan Casanova, N., Guignot,N., Bouhifd, M.A.Uranium in the Earth's lower mantle.Geophysical Research Letters, Vol. 33, 23, Dec. 16, L23301MantleUranium
DS201803-0432
2018
Guignot, N.Andrault, D., Pesce, G., Manthilake, G., Monteux, J., Volfan-Casanova, N., Chantel, J. , Novella, D., Guignot, N., King, A., Itie, J-P., Hennet, L.An archean mushy mantle.Nature Geoscience, Vol. 11, 2, pp. 85-86.Mantlegeodynamics

Abstract: Experimental data reveal that Earth’s mantle melts more readily than previously thought, and may have remained mushy until two to three billion years ago.
DS202002-0215
2020
Guignot, N.Ritter, X., Sanchez-Valle, C., Sator, N., Desmaele, E., Guignot, N., King, A., Kupenko, I., Berndt, J., Guillot, B.Density of hydrous carbonate melts under pressure, compressability of volatiles and implications for carbonate melt mobility in the upper mantle.Earth and Planetary Science Letters, Vol. 533, 11p. PdfMantlecarbon

Abstract: Knowledge of the effect of water on the density of carbonate melts is fundamental to constrain their mobility in the Earth's interior and the exchanges of carbon between deep and surficial reservoirs. Here we determine the density of hydrous MgCO3 and CaMg(CO3)2 melts (10 wt% H2O) from 1.09 to 2.98 GPa and 1111 to 1763 K by the X-ray absorption method in a Paris-Edinburgh press and report the first equations of state for hydrous carbonate melts at high pressure. Densities range from 2.26(3) to 2.50(3) g/cm3 and from 2.34(3) to 2.48(3) g/cm3 for hydrous MgCO3 and CaMg(CO3)2 melts, respectively. Combining the results with density data for the dry counterparts from classical Molecular Dynamic (MD) simulations, we derive the partial molar volume (, ) and compressibility of H2O and CO2 components at crustal and upper mantle conditions. Our results show that in alkaline carbonate melts is larger and less compressible than at the investigated conditions. Neither the compressibility nor depend on carbonate melt composition within uncertainties, but they are larger than those in silicate melts at crustal conditions. in alkaline earth carbonate melts decreases from 25(1) to 16.5(5) cm3/mol between 0.5 and 4 GPa at 1500 K. Contrastingly, comparison of our results with literature data suggests strong compositional effects on , that is also less compressible than in transitional melts (e.g., kimberlites) and carbonated basalts. We further quantify the effect of hydration on the mobility of carbonate melts in the upper mantle and demonstrate that 10 wt% H2O increases the mobility of MgCO3 melts from 37 to 67 g.cm?3.Pa?1s?1 at 120 km depth. These results suggest efficient carbonate melt extraction during partial melting and fast migration of incipient melts in the shallow upper mantle.
DS201012-0007
2010
Guigot, N.Andrault, D., Munoz, M., Bolfan-Casanova, N., Guigot, N., Schouten, J-P.Experiment evidence for perovskite and post perovskite coexistence throughout the whole 'D' region.Earth and Planetary Science Letters, Vol. 293, 1-2, pp. 90-96.MantleBoundary
DS201212-0269
2012
Guilani, A.Guilani, A., Kendrick, M.A., Phillips, D.Halogen and AR geochemistry of metasomatic mantle xenoliths from the Bultfontein pipe (Kimberley district, South Africa).10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, South AfricaDeposit - Bultfontein
DS1970-0766
1973
Guilbert, C.M.Meyer, H.O.A., Guilbert, C.M., Taylor, L.A., Sears, C.E.Mineralogy of Mica Peridotite, Lake NorrisEos, Vol. 54, No. 4, P. 493. (abstract.).Appalachia, TennesseeRelated Rocks
DS1910-0052
1910
Guild, F.N.Guild, F.N.The Mineralogy of ArizonaEaston, Pa.: The Chemical Printing Co., 103P.United States, Arizona, Colorado PlateauBlank
DS200512-0379
2005
Guilderson, T.P.Guilderson, T.P., Reimer, P.J., Brown, T.A.The boon and the bane of radiocarbon dating.Science, Vol. 307, 5708, Jan. 21, pp. 362-3.Radiocarbon technology - not specific to diamonds
DS1984-0469
1984
Guilford, C.Mackenzie, W.S., Donaldson, C.H., Guilford, C.Kimberlite and Garnet PeridotiteAtlas of Igneous Rocks And Their Textures, J.wiley- Halstead, 148P. PP. 81-82.GlobalPhotomicrographs
DS1995-0694
1995
Guilhaumou, N.Guilhaumou, N., Larroque, C.Les circulations de fluides dans les prismes d'accretion: fluides fossile set fluides actuelsC.r. Academy Of Science Paris, Vol. 321, 11a, pp. 939-957GlobalGeodynamics, Paleomarkers
DS200512-0380
2005
Guilhaumou, N.Guilhaumou, N., Sautter, V., Dumas, P.Synchrotron FTIR microanalysis of volatiles in melt inclusions and exsolved particles in ultramafic deep seated garnets.Chemical Geology, In press.Africa, South AfricaJagersfontein, ultradeep xenoliths, partial melting
DS201312-0344
2013
Guiliani, A.Guiliani, A., Phillips, D., Fiorentini, M.L., Kendrick, M.A., Maas, R., Wing, B.A., Woodhead, J.D., Bui, T.H., Kamenetsky, V.S.Mantle oddities: a sulphate fluid preserved in a MARID xenolith from the Bultfontein kimberlite ( Kimberley South Africa).Earth and Planetary Science Letters, Vol. 376, pp. 74-86.Africa, South AfricaDeposit - Bultfontein
DS201605-0841
2016
Guiliani, A.Guiliani, A.Trace element traverses across kimberlite olivine: a new tool to decipher the evolution of kimberlite magmas.DCO Edmonton Diamond Workshop, June 8-10TechnologyMagmatism
DS201607-1351
2016
Guiliani, A.Guiliani, A.Trace element variations across olivine record the evolution of kimberlite melts: case studies from the Kimberley kimberlites ( South Africa).IGC 35th., Session A Dynamic Earth 1p. AbstractAfrica, South AfricaKimberlite
DS201708-1583
2017
Guiliani, A.Woodhead, J., Hergt, J., Guiliani, A., Phillips, D., Maas, R.Tracking continental style scale modification of the Earth's mantle using zircon megacrysts. KimberlitesGeochemical Perspectives Letters, Vol. 4, pp. 1-6.Africa, South Africa, Zimbabwemetasomatism, geochronology

Abstract: Metasomatism, the chemical alteration of rocks by a variety of melts and fluids, has formed a key concept in studies of the Earth’s mantle for decades. Metasomatic effects are often inferred to be far-reaching and yet the evidence for their occurrence is usually based upon individual hand specimens or suites of rocks that display considerable heterogeneity. In rare cases, however, we are offered insights into larger-scale chemical modifications that occur in the mantle. Here we utilise the Lu–Hf systematics of zircon megacrysts erupted in kimberlite magmas to discern two temporally and compositionally discrete metasomatic events in the mantle beneath southern Africa, each having an influence extending over an area exceeding one million km2. These data provide unambiguous evidence for metasomatic processes operating at continental scales and seemingly unperturbed by the age and composition of the local lithospheric mantle. The most recent of these events may be associated with the major Jurassic-Karoo magmatism in southern Africa.
DS202204-0521
2022
Guiliani, A.Guiliani, A., Drysdale, R.N., Woodhead, J.D., Planavsky, N.J., Phillips, D., Hergt, J., Griffin, W.L., Oesch, S., Dalton, H., Davies, G.R.Pertubation of the deep-Earth carbon cycle in response to the Cambrian explosion.Science Advances, doi.10.1126/sciadv.abj1325 1p. PdfMantlesubduction

Abstract: Earth’s carbon cycle is strongly influenced by subduction of sedimentary material into the mantle. The composition of the sedimentary subduction flux has changed considerably over Earth’s history, but the impact of these changes on the mantle carbon cycle is unclear. Here, we show that the carbon isotopes of kimberlite magmas record a fundamental change in their deep-mantle source compositions during the Phanerozoic Eon. The 13C/12C of kimberlites before ~250 Ma preserves typical mantle values, whereas younger kimberlites exhibit lower and more variable ratios-a switch coincident with a recognized surge in kimberlite magmatism. We attribute these changes to increased deep subduction of organic carbon with low 13C/12C following the Cambrian Explosion when organic carbon deposition in marine sediments increased significantly. These observations demonstrate that biogeochemical processes at Earth’s surface have a profound influence on the deep mantle, revealing an integral link between the deep and shallow carbon cycles.
DS2001-0424
2001
Guililer, B.Guililer, B., Chatelain, J.L., Jaillard, Yepes et al.Seismological evidence on the geometry of the orogenic system in central northern Ecuador.Geophysical Research Letters, Vol. 28, No. 19, Oct. 1, pp. 3749-52.Ecuador, South AmericaGeophysics - seismics, Tectonics
DS1996-0934
1996
Guilinger, J.R.McLemore, V.T., Lueth, V.W., Pease, T.C., Guilinger, J.R.Petrology and mineral resources of the Wind River laccolith, CornudasMountains, New Mexico and TexasCanadian Mineralogist, Vol. 34, pt. 2, April pp. 335-348.New Mexico, TexasAlkaline rocks
DS1996-0947
1996
Guillande, R.Mering, C., Huaman-Rodrigo, D., Guillande, R.New dat a on the geodynamics of southern Peru from computerized analysis of SPOT and SAR ERS 1 imagesTectonophysics, Vol. 259, No. 1-3, June 30, pp. 153-170PeruGeodynamics, Remote sensing
DS201412-0068
2014
GuillaumeBraun, J., Guillocheau, F., Robin, C., Baby, Guillaume, JelsmaRapid erosion of the southern African plateau as it climbs over a mantle superswell.Journal of Geophysical Research,, Vol. 119, 7, pp. 6093-6112.Africa, southern AfricaGeomorphology
DS201412-0724
2013
Guillaume, D.Rasoamalala, V., Salvi, S., Bexiat, D., Ursule, J-Ph., Cuney, M., De Parseval, Ph., Guillaume, D., Moine, B., Andriamampihantona, J.Geology of bastnaesite and monazite deposits in the Ambatofinandrahana area, central part of Madagascar: an overview.Journal of African Earth Sciences, Vol. 94, 14p.Africa, MadagascarBastanesite
DS2001-0425
2001
Guillen, A.Guillen, A., Meunier, Ch., Repusseau, Ph.New internet tools to manage geological and geophysical dataComputers and Geosciences, Vol. 27, No. 5, pp. 563-76.GlobalComputer - World wide web
DS201412-0577
2014
Guillermier, C.Mikhail, S., Guillermier, C., Franchi, I.A., Beard, A.D., Crispin, K., Verchovsky, A.B., Jones, A.P., Milledge, H.J.Empirical evidence for the fractionation of carbon isotopes between diamond and iron carbide from the Earth's mantle.Geochemistry, Geophysics, Geosystems: G3, Vol. 15, 4, pp. 855-866.MantleGeochronology
DS1990-0610
1990
Guillet, G.R.Guillet, G.R.Exploration techniques for industrial mineralsThe Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Annual Meeting Paper preprint, No. 107, 11pGlobalIndustrial minerals, Exploration
DS1996-1141
1996
Guillier, B.Prevot, R., Chatelain, J-L., Guillier, B., Yepes, H.Tomographie des Andes equatoriennes evidence d'une continuite des AndesCentralesC.r. Academy Of Science Paris, Vol. 323, 11a, pp. 833-840Bolivia, Ecuador, AndesTomography, Geophysics - seismics
DS201312-0187
2013
Guillocheau, F.Dauteuil, O., Deschamps, F., Bourgeois, O., Mocquet, A., Guillocheau, F.Post breakup evolution and paleotopography of the North Namibia margin during the Meso-Cenozoic.Tectonophysics, Vol. 589, pp. 103-115.Africa, NamibiaTectonics
DS201412-0068
2014
Guillocheau, F.Braun, J., Guillocheau, F., Robin, C., Baby, Guillaume, JelsmaRapid erosion of the southern African plateau as it climbs over a mantle superswell.Journal of Geophysical Research,, Vol. 119, 7, pp. 6093-6112.Africa, southern AfricaGeomorphology
DS201503-0140
2015
Guillocheau, F.Dauteuil, O., Bessin, P., Guillocheau, F.Topographic growth around the Orange River valley, southern Africa: a Cenozoic record of crustal deformation and climatic change.Geomorphology, Vol. 233, March 15, pp. 5-19.Africa, South AfricaOrange River

Abstract: We reconstruct the history of topographic growth in southern Africa on both sides of the Orange River valley from an integrated analysis of erosion surfaces, crustal deformation and climate change. First, we propose an inventory of erosion surfaces observed in the study area and classify them according to their most likely formative process, i.e. chemical weathering or mechanical erosion. Among the various land units observed we define a new class of landform: the pedivalley, which corresponds to a wide valley with a flat erosional floor. In the Orange River valley, we mapped three low-relief erosion surfaces, each bevelling a variety of lithologies. The oldest and most elevated is (1) a stripped etchplain evolving laterally into (2) a stepped pediplain bearing residual inselbergs; (3) a younger pediplain later formed in response to a more recent event of crustal deformation. These are all Cenozoic landforms: the etchplain is associated with a late Palaeocene to middle Eocene weathering event, and the two pediplains are older than the middle Miocene alluvial terraces of the Orange River. Landscape evolution was first driven by slow uplift (10 m/Ma), followed by a second interval of uplift involving a cumulative magnitude of at least 200 m. This event shaped the transition between the two pediplains and modified the drainage pattern. A final phase of uplift (magnitude: 60 m) occurred after the Middle Miocene and drove the incision of the lower terraces of the Orange River. Climate exerted a major control over the denudation process, and involved very humid conditions responsible for lateritic weathering, followed by more arid conditions, which promoted the formation of pedivalleys. Collectively, these produce pediplains.
DS201801-0020
2018
Guillocheau, F.Guillocheau, F., Simon, B., Baby, G., Bessin, P., Robin, C., Dauteuil, O.Planation surfaces as a record of mantle dynamics: the case of Africa.Gondwana Research, Vol. 53, 1, pp. 82-98.Africageodynamics

Abstract: There are two types of emerged relief on the Earth: high elevation areas (mountain belts and rift shoulders) in active tectonic settings and low elevation domains (anorogenic plateaus and plains) characteristic of the interior of the continents i.e. 70% of the Earth emerged relief. Both plateaus and plains are characterized by large erosional surfaces, called planation surfaces that display undulations with middle (several tens of kilometres) to very long (several thousands of kilometres) wavelengths, i.e. characteristic of lithospheric and mantle deformations respectively. Our objective is here (1) to present a new method of characterization of the very long and long wavelength deformations using planation surfaces with an application to Central Africa and (2) to reconstruct the growth of the very long wavelength relief since 40 Ma, as a record of past mantle dynamics below Central Africa. (i) The African relief results from two major types of planation surfaces, etchplains (weathering surfaces by laterites) and pediplains/pediments. These planation surfaces are stepped along plateaus with different elevations. This stepping of landforms records a local base level fall due to a local tectonic uplift. (ii) Central Africa is an extensive etchplain-type weathering surface - called the African Surface - from the uppermost Cretaceous (70 Ma) to the Middle Eocene (45 Ma) with a paroxysm around the Early Eocene Climatic Optimum. Restoration of this surface in Central Africa suggests very low-elevation planation surfaces adjusted to the Atlantic Ocean and Indian Ocean with a divide located around the present-day eastern branch of the East African Rift. (iii) The present-day topography of Central Africa is younger than 40 -30 Ma and records very long wavelength deformations (1000 -2000 km) with (1) the growth of the Cameroon Dome and East African Dome since 34 Ma, (2) the Angola Mountains since 15 -12 Ma increasing up to Pleistocene times and (3) the uplift of the low-elevation (300 m) Congo Basin since 10 -3 Ma. Some long wavelength deformations (several 100 km) also occurred with (1) the low-elevation Central African Rise since 34 Ma and (2) the Atlantic Bulge since 20 -16 Ma. These very long wavelength deformations record mantle dynamics, with a sharp increase of mantle upwelling around 34 Ma and an increase of the wavelength of the deformation and then of mantle convection around 10 -3 Ma.
DS202202-0212
2021
Guillocheau, F.Roche, V., Leroy, S., Guillocheau, F., Revillon, S., Ruffet, G., Watremez, L., d'Acremont, E., Nonn, C., Vetel, W., Despinois, F.The Limpopo magma-rich transform margin, south Mozambique - pt. 2. Implications for the Gondwana breakup.Tectonics, e2021TC006914 Africa, Mozambiquegeophysics - seismics

Abstract: The rifted continental margins of Mozambique provide excellent examples of continental passive margins with a significant structural variability associated with magmatism and inheritance. Despite accumulated knowledge, the tectonic structure and nature of the crust beneath the South Mozambique Coastal Plain (SMCP) are still poorly known. This study interprets high-resolution seismic reflection data paired with data from industry-drilled wells and proposes a structural model of the Limpopo transform margin in a magma-rich context. Results indicate that the Limpopo transform margin is characterized by an ocean-continent transition that links the Beira-High and Natal valley margin segments and represents the western limit of the continental crust, separating continental volcano-sedimentary infilled grabens from the oceanic crust domain. These basins result from the emplacement of the Karoo Supergroup during a Permo-Triassic tectonic event, followed by an Early Jurassic tectonic and magmatic event. This latter led to the establishment of steady-state seafloor spreading at ca.156 Ma along the SMCP. A Late Jurassic to Early Cretaceous event corresponds to formation of the Limpopo transform fault zone. Which accommodated the SSE-ward displacement of Antarctica with respect to Africa. We define a new type of margin: the magma-rich transform margin, characterized by the presence of voluminous magmatic extrusion and intrusion coincident with the formation and evolution of the transform margin. The Limpopo transform fault zone consists of several syn-transfer and -transform faults rather than a single transform fault. The intense magmatic activity was associated primarily with mantle dynamics, which controlled the large-scale differential subsidence along the transform margin.
DS201707-1342
2017
Guillong, M.Kueter, N., Soesilo, J., Fedortchouk, Y., Nestola, F., Belluco, L., Troch, J., Walle, M., Guillong, M., Von Quadt, A., Driesner, T.Tracing the depositional history of Kalimantan diamonds by zircon proveneance and diamond morphology studies. Appendix 1 and 2Academia.edu, Supplementary material app. 1 and 2, both 10p.Asia, Kalimantandeposit - Kalimantan

Abstract: Diamonds in alluvial deposits in Southeast Asia are not accompanied by indicator minerals suggesting primary kimberlite or lamproite sources. The Meratus Mountains in Southeast Borneo (Province Kalimantan Selatan, Indonesia) provide the largest known deposit of these so-called “headless” diamond deposits. Proposals for the origin of Kalimantan diamonds include the adjacent Meratus ophiolite complex, ultra-high pressure (UHP) metamorphic terranes, obducted subcontinental lithospheric mantle and undiscovered kimberlite-type sources. Here we report results from detailed sediment provenance analysis of diamond-bearing Quaternary river channel material and from representative outcrops of the oldest known formations within the Alino Group, including the diamond-bearing Campanian–Maastrichtian Manunggul Formation. Optical examination of surfaces of diamonds collected from artisanal miners in the Meratus area (247 stones) and in West Borneo (Sanggau Area, Province Kalimantan Barat; 85 stones) points toward a classical kimberlite-type source for the majority of these diamonds. Some of the diamonds host mineral inclusions suitable for deep single-crystal X-ray diffraction investigation. We determined the depth of formation of two olivines, one coesite and one peridotitic garnet inclusion. Pressure of formation estimates for the peridotitic garnet at independently derived temperatures of 930–1250 °C are between 4.8 and 6.0 GPa. Sediment provenance analysis includes petrography coupled to analyses of detrital garnet and glaucophane. The compositions of these key minerals do not indicate kimberlite-derived material. By analyzing almost 1400 zircons for trace element concentrations with laser ablation ICP-MS (LA-ICP-MS) we tested the mineral's potential as an alternative kimberlite indicator. The screening ultimately resulted in a small subset of ten zircons with a kimberlitic affinity. Subsequent U–Pb dating resulting in Cretaceous ages plus a detailed chemical reflection make a kimberlitic origin unfavorable with respect to the regional geological history. Rather, trace elemental analyses (U, Th and Eu) suggest an eclogitic source for these zircons. The age distribution of detrital zircons allows in general a better understanding of collisional events that formed the Meratus orogen and identifies various North Australian Orogens as potential Pre-Mesozoic sediment sources. Our data support a model whereby the majority of Kalimantan diamonds were emplaced within the North Australian Craton by volcanic processes. Partly re-deposited into paleo-collectors or residing in their primary host, these diamond-deposits spread passively throughout Southeast Asia by terrane migration during the Gondwana breakup. Terrane amalgamation events largely metamorphosed these diamond-bearing lithologies while destroying the indicative mineral content. Orogenic uplift finally liberated their diamond-content into new, autochthonous placer deposits.
DS201603-0402
2016
Guillot, B.Moussallam, Y., Florian, P., Corradini, D., Morizet, Y., Sator, N., Vuilleumier, R., Guillot, B., Iacono-Marziano, G., Schmidt, B.C., Gaillard, F.The molecular structure of melts along the carbonatite-kimberlite-basalt compositional joint: CO (sub 2) and polymerisation.Earth and Planetary Science Letters, Vol. 434, pp. 129-140.TechnologyPetrology - experimental

Abstract: Transitional melts, intermediate in composition between silicate and carbonate melts, form by low degree partial melting of mantle peridotite and might be the most abundant type of melt in the asthenosphere. Their role in the transport of volatile elements and in metasomatic processes at the planetary scale might be significant yet they have remained largely unstudied. Their molecular structure has remained elusive in part because these melts are difficult to quench to glass. Here we use FTIR, Raman, 13C and 29Si NMR spectroscopy together with First Principle Molecular Dynamic (FPMD) simulations to investigate the molecular structure of transitional melts and in particular to assess the effect of CO2 on their structure. We found that carbon in these glasses forms free ionic carbonate groups attracting cations away from their usual ‘depolymerising’ role in breaking up the covalent silicate network. Solution of CO2 in these melts strongly modifies their structure resulting in a significant polymerisation of the aluminosilicate network with a decrease in NBO/Si of about 0.2 for every 5 mol% CO2 dissolved. This polymerisation effect is expected to influence the physical and transport properties of transitional melts. An increase in viscosity is expected with increasing CO2 content, potentially leading to melt ponding at certain levels in the mantle such as at the lithosphere-asthenosphere boundary. Conversely an ascending and degassing transitional melt such as a kimberlite would become increasingly fluid during ascent hence potentially accelerate. Carbon-rich transitional melts are effectively composed of two sub-networks: a carbonate and a silicate one leading to peculiar physical and transport properties.
DS202002-0215
2020
Guillot, B.Ritter, X., Sanchez-Valle, C., Sator, N., Desmaele, E., Guignot, N., King, A., Kupenko, I., Berndt, J., Guillot, B.Density of hydrous carbonate melts under pressure, compressability of volatiles and implications for carbonate melt mobility in the upper mantle.Earth and Planetary Science Letters, Vol. 533, 11p. PdfMantlecarbon

Abstract: Knowledge of the effect of water on the density of carbonate melts is fundamental to constrain their mobility in the Earth's interior and the exchanges of carbon between deep and surficial reservoirs. Here we determine the density of hydrous MgCO3 and CaMg(CO3)2 melts (10 wt% H2O) from 1.09 to 2.98 GPa and 1111 to 1763 K by the X-ray absorption method in a Paris-Edinburgh press and report the first equations of state for hydrous carbonate melts at high pressure. Densities range from 2.26(3) to 2.50(3) g/cm3 and from 2.34(3) to 2.48(3) g/cm3 for hydrous MgCO3 and CaMg(CO3)2 melts, respectively. Combining the results with density data for the dry counterparts from classical Molecular Dynamic (MD) simulations, we derive the partial molar volume (, ) and compressibility of H2O and CO2 components at crustal and upper mantle conditions. Our results show that in alkaline carbonate melts is larger and less compressible than at the investigated conditions. Neither the compressibility nor depend on carbonate melt composition within uncertainties, but they are larger than those in silicate melts at crustal conditions. in alkaline earth carbonate melts decreases from 25(1) to 16.5(5) cm3/mol between 0.5 and 4 GPa at 1500 K. Contrastingly, comparison of our results with literature data suggests strong compositional effects on , that is also less compressible than in transitional melts (e.g., kimberlites) and carbonated basalts. We further quantify the effect of hydration on the mobility of carbonate melts in the upper mantle and demonstrate that 10 wt% H2O increases the mobility of MgCO3 melts from 37 to 67 g.cm?3.Pa?1s?1 at 120 km depth. These results suggest efficient carbonate melt extraction during partial melting and fast migration of incipient melts in the shallow upper mantle.
DS202102-0190
2019
Guillot, B.Gaillard, F., Sator, N., Guillot, B., Massuyeau, M.The link between the physical and chemical properties of carbon-bearing melts and their application for geophysical imaging of Earth's mantleResearchgate , DOI: 10.1017/ 9781108677950.007 26p. Pdfmantlecarbon

Abstract: Significant investment in new capacities for experimental research at high temperatures and pressures have provided new levels of understanding about the physical properties of carbon in fluids and melts, including its viscosity, electrical conductivity, and density. This chapter reviews the physical properties of carbon-bearing melts and fluids at high temperatures and pressures and highlights remaining unknowns left to be explored. The chapter also reviews how the remote sensing of the inaccessible parts of the Earth via various geophysical techniques - seismic shear wave velocity, attenuation, and electromagnetic signals of mantle depths - can be reconciled with the potential presence of carbon-bearing melts or fluids.
DS2001-0009
2001
Guillot, S.Agbossoumonde, Y., Menot, R.P., Guillot, S.Metamorphic evolution of Neoproterozoic eclogites from south To go (West Africa)Journal of African Earth Sciences, Vol.33,2,Aug.pp.227-44.Togo, West AfricaEclogites, Metamorphism
DS2001-0426
2001
Guillot, S.Guillot, S., Hattoriu, K.H., DeSigoyer, Nagler, AuzendeEvidence of hydration of the mantle wedge and its role in the exhumation of eclogitesEarth and Planetary Science Letters, Vol. 193, No. 2, pp. 115-27.MantleSubduction, Eclogites
DS2001-1042
2001
Guillot, S.Schwartz, S., Allemand, P., Guillot, S.Numerical model of the effect of serpentinites on the exhumation of eclogitic rocks: insights from...Tectonophysics, Vol. 342, No. 2, pp. 193-206.AlpsMonviso ophiolitic complex, Eclogites
DS2003-0562
2003
Guillot, S.Hattori, K.H., Guillot, S.Volcanic fronts form as a consequence of serpentinite dehydration in the forearc mantleGeology, Vol. 31, 6, June pp. 525-8.MantleBlank
DS200412-0804
2003
Guillot, S.Hattori, K.H., Guillot, S.Volcanic fronts form as a consequence of serpentinite dehydration in the forearc mantle wedge.Geology, Vol. 31, 6, June pp. 525-8.MantleSubduction - not specific to diamonds
DS201012-0622
2010
Guillot, S.Replumaz, A., Negredo, A.M., Villasenor, A., Guillot, S.Indian continental subduction and slab break off during Tertiary collision.Terra Nova, Vol. 22, pp. 290-296.IndiaSubduction
DS201811-2598
2018
Guillot, S.Page, L., Hattori, K., Guillot, S.Mantle wedge serpentinites: a transient reservoir of halogens, boron and nitrogen for the deeper mantle.Geology, Vol. 46, 9, pp. 883-886.Mantlenitrogen

Abstract: Fluorine (50-650 ppm), bromine (0.03-0.3 ppm), iodine (0.03-0.4 ppm), boron (20-100 ppm) and nitrogen (5-45 ppm) concentrations are elevated in antigorite-serpentinites associated with the Tso Morari ultrahigh-pressure unit (Himalayas) exhumed from >100 km depth in the mantle wedge. These fluid-mobile elements are likely released with fluids from subducted marine sediments on the Indian continental margin to hydrate overlying forearc serpentinites at shallow depths. Of these, F and B appear to remain in serpentinites during the lizardite-antigorite transition. Our results demonstrate serpentinites as transient reservoirs of halogens, B, and N to at least 100 km depth in the mantle wedge, and likely deeper in colder slabs, providing a mechanism for their transport to the deeper mantle.
DS200812-0636
2008
Guillou, H.Le Gall, B., Nonnotte, P., Rolet, J., Benoit, M., Guillou, H., Mousseau Nonnotte, M., Albaric, DeverchreRift propogation at craton margin: distribution of faulting and volcanism in the north Tanzanian divergence ( East Africa) during Neogene times.Tectonophysics, Vol. 448, 1-4, pp. 1-19.Africa, TanzaniaMagmatism
DS1995-0695
1995
Guillou, L.Guillou, L., Jaupart, C.On the effect of continents on mantle convectionJournal of Geophysical Research, Vol. 100, No. B12, Dec. 10, pp. 24, 217-38MantleSubduction, Tectonics
DS1995-0696
1995
Guillou, L.Guillou, L., Jaupart, C.On the effect of continents on mantle convectionJournal of Geophysical Research, Vol. 100, No. B12, Dec. 10, pp. 24, 217-238.Mantle, crustTectonics -review, Mantle convection
DS200712-0125
2007
Guillou Frottier, L.Burov, E.,Guillou Frottier, L., Acremont, E., Le Pourthier, L., Cloetingh, S.Plume head lithosphere interactions near intra continental plate boundaries.Tectonophysics, Vol. 434, 1-4, pp. 15-38.MantleHotspots
DS2003-0192
2003
Guillou-Frottier, L.Burov, E., Jaupart, C., Guillou-Frottier, L.Ascent and emplacement of bouyant magma bodies in brittle ductile upper crustJournal of Geophysical Research, Vol. 108, B4, April 1, DOI 10.1029/2002JB001904.MantleMagmatism - not specific to diamonds
DS200412-0249
2003
Guillou-Frottier, L.Burov, E., Jaupart, C., Guillou-Frottier, L.Ascent and emplacement of bouyant magma bodies in brittle ductile upper crust.Journal of Geophysical Research, Vol. 108, B4, April 1, DOI 10.1029/2002 JB001904.MantleMagmatism - not specific to diamonds
DS200512-0124
2005
Guillou-Frottier, L.Burov, E., Guillou-Frottier, L.The plume head continental lithosphere interaction using a technically realistic formulation for the lithosphere.Geophysical Journal International, Vol. 161, 2, pp. 469-490.MantleHotspots, plumes
DS200512-0125
2005
Guillou-Frottier, L.Burov, E., Guillou-Frottier, L.The plume head - continental lithosphere interaction using a tectonically realistic formulation for the lithosphere.Chapman Conference held in Scotland August 28-Sept. 1 2005, 1p. abstractMantleMantle plume
DS202104-0579
2021
Guilmette, C.Godet, A., Guilmette, C.,Labrousse, L., Smit, M.A., Cutts, J.A., Davis, D.W., Vanier, M-A.Lu-Hf garnet dating and the timing of collisions: Paleoproterozoic accretionary tectonics revealed in the southeastern Churchill Province Trans-Hudson Orogen, Canada. Torngat, New QuebecJournal of Metamorphic Geology, doi:10.1111/jmg.12599Canada, Quebeccratons

Abstract: Dating the onset of continental collision is fundamental in defining orogenic cycles and their effects on regional tectonics and geodynamic processes through time. Part of the Palaeoproterozoic Trans?Hudson Orogen, the Southeastern Churchill Province (SECP) is interpreted to result from the amalgamation of Archean to Palaeoproterozoic crustal blocks (amalgamated as the central Core Zone) that diachronically collided with the margins of the North Atlantic and Superior cratons, resulting in two bounding transpressive orogens: the Torngat and New Quebec Orogens. The SECP exposes mainly gneissic middle to lower orogenic crust in which deformation and amphibolite to granulite facies metamorphism and anatexis overprinted the early geological features classically used to constrain the timing of collisional events. To enable improved tectonic models for the development of the SECP, and the Trans?Hudson as a whole, we investigated granulite facies supracrustal sequences from the Tasiuyak Complex (TC) accretionary prism and the western margin of the North Atlantic Craton-that is, Saglek Block (upper plate)-using a multi?chronometer approach coupled with trace element geochemistry. In particular, the use of garnet Lu-Hf geochronology provides an important minimal time constraint for crustal thickening and collision. Garnet growth in the TC is constrained at 1885 ± 12 Ma (Lu-Hf), indistinguishable from U-Pb age of prograde monazite at 1873 ± 5 Ma. Zircon growth during melt crystallization occurred at 1848 ± 12 Ma. Garnet from the overriding Saglek Block is dated at 2567 ± 4.4 Ma (Lu-Hf) and indicates that gneissic rocks from the upper plate did not record the metamorphic imprint of the Torngat Orogeny. The diachronicity of the integrated metamorphic record across the strike of the SECP is explained by the location of terrane boundaries, consistent with the westward growth of the Churchill plate margin through sequential amalgamation of narrow crustal blocks during accretionary tectonics from c. 1.9 to 1.8 Ga.
DS202111-1767
2021
Guilmette, C.Godet, A., Guilmette, C., Labrousse, L., Smit, M.A., Cutts, J.A., Davis, D.W., Vanier, M-A.Lu-Hf garnet dating and the timing of collisions: Paleoproterozoic accretionary tectonics revealed in the southeastern Churchill Province, Trans-Hudson orogen, Canada.Journal of Metamorphic Geology, Vol. 39, 8, 31p. PdfCanadageochronology

Abstract: Dating the onset of continental collision is fundamental in defining orogenic cycles and their effects on regional tectonics and geodynamic processes through time. Part of the Palaeoproterozoic Trans-Hudson Orogen, the Southeastern Churchill Province (SECP) is interpreted to result from the amalgamation of Archean to Palaeoproterozoic crustal blocks (amalgamated as the central Core Zone) that diachronically collided with the margins of the North Atlantic and Superior cratons, resulting in two bounding transpressive orogens: the Torngat and New Quebec Orogens. The SECP exposes mainly gneissic middle to lower orogenic crust in which deformation and amphibolite to granulite facies metamorphism and anatexis overprinted the early geological features classically used to constrain the timing of collisional events. To enable improved tectonic models for the development of the SECP, and the Trans-Hudson as a whole, we investigated granulite facies supracrustal sequences from the Tasiuyak Complex (TC) accretionary prism and the western margin of the North Atlantic Craton—that is, Saglek Block (upper plate)—using a multi-chronometer approach coupled with trace element geochemistry. In particular, the use of garnet Lu-Hf geochronology provides an important minimal time constraint for crustal thickening and collision. Garnet growth in the TC is constrained at 1885 ± 12 Ma (Lu-Hf), indistinguishable from U-Pb age of prograde monazite at 1873 ± 5 Ma. Zircon growth during melt crystallization occurred at 1848 ± 12 Ma. Garnet from the overriding Saglek Block is dated at 2567 ± 4.4 Ma (Lu-Hf) and indicates that gneissic rocks from the upper plate did not record the metamorphic imprint of the Torngat Orogeny. The diachronicity of the integrated metamorphic record across the strike of the SECP is explained by the location of terrane boundaries, consistent with the westward growth of the Churchill plate margin through sequential amalgamation of narrow crustal blocks during accretionary tectonics from c. 1.9 to 1.8 Ga.
DS1992-0628
1992
Guilov, P.Guilov, P., Gent, M.R.Review of industrial minerals investigations 1992-1993. Kimberlite indicator mineral samplingSaskatchewan Report Summary of Investigations 1992, miscellaneous Report No. 92-4, pp. 197-198SaskatchewanGeochemistry, Indicator minerals, kimberlite sampling
DS2000-0213
2000
GuimaraesDe Carvalho, H., Tassinari, C., Alvesm P.H., GuimaraesGeochronological review of the Precambrian in western Angola: links with Brasil.Journal of African Earth Sciences, Vol. 31, No. 2, Aug. pp. 383-402.Angola, BrazilGeochronology, Tectonics - Congo, Sao Francisco Craton
DS1930-0161
1934
Guimaraes, D.Guimaraes, D.A Margem de " Os Satelites Do Diamante"Belo Horizonte: Minas Gerais Serv. Geol. Monograph, No. 2, 57P. XEROX.BrazilKimberlite, Kimberley, Janlib, Mineralogy
DS1950-0102
1952
Guimaraes, D.Guimaraes, D.O Carbonado Da BahiaSalvador: Institute Tecnol. Bahia., Publishing No. 3, 45P.BrazilKimberlite, Kimberley, Janlib, Diamond
DS200812-0388
2008
Guimaraes, E.Garnier, J., Quantin, C., Guimaraes, E., Bequer, T.Can chromite weathering be a source of Cr in soils?Mineralogical Magazine, Vol. 72, 1, pp. 49-53.TechnologyChromite - not specific to diamonds
DS1993-0309
1993
Guimaraes, I.P.Da Silva Filho, A.F., Guimaraes, I.P., Thompson, R.N.Shoshonitic and ultrapotassic Proterozoic intrusive suites in the Cachoeirinha-Saigueiro belt, northeast Brasil: a transition collisional to post-collisional magmatismPrecambrian Research, Vol. 62, No. 3, June pp. 323-342BrazilShoshonites, Ultrapotassic rocks
DS1997-0235
1997
Guimaraes, I.P.Da Silva Filho, A.F., Guimaraes, I.P., Pimentel, M.M.Geochemical signatures of main Neoproterozoic late tectonic granitoids from Proterozoic Sergipano beltInternational Geol. Rev, Vol. 39, No. 7, July, pp. 639-659BrazilGeochemistry - Sergipano, Brasiliano Orogeny
DS201112-0232
2011
Guimaraes, I.P.Da Silva Filio, A.F., Guimaraes, I.P., Armstrong, R.A.SHRIMP U Pb geochronology of Neoproterzoic Rio Una sequence, NE Brazil and the Rodinia break-up.Goldschmidt Conference 2011, abstract p.724.South America, Brazil, AfricaGondwana - Borborema Province
DS2000-0706
2000
GuimaresNeves, S.P., Mariano, G., Guimares, da Silva Filho, MeloIntralithospheric differentiation and crustal growth: evidence from Bororema province, northeastern BrasilGeology, Vol. 28, No. 6, June pp. 519-22.BrazilAlkaline rocks, Geochemistry, Proterozoic crustal growth
DS1996-0457
1996
Guimares, I.F.Filho, A.F. Da Silva, Guimares, I.F., Kozuch, M.Mineral chemistry and tectonic significance of NeoProterozoic ultrapotassic plutonic rocks ....International Geology Review, Vol. 38, No. 7, July pp. 649-664.BrazilCocheoerinha Salgueiro fold belt, Alkaline rocks
DS1990-0943
1990
GuiminLiu, Guimin, Becker, A.Evaluation of terrain effects in airborne electromagnetic surveysSociety of Exploration Geophysicists, 60th. Annual Meeting held, San, Vol. 1, pp. 700-703. Extended abstractGlobalGeophysics, electromagnetic -airborne
DS1994-0672
1994
Guindon, B.Guindon, B.The generation of large area mosaics from ERS- 1 SAR imageryCanadian Journal of Remote Sensing, Vol. 20, No. 3, Sept. pp. 317-318CanadaRemote sensing, SAR images -brief note
DS2001-0427
2001
Guindon, D.Guindon, D.Using operation treasure hunt dat a to search for kimberlite pipes #1Ontario Geological Survey, Northeastern Mineral Symposium, p.8, abstract.OntarioGeophysics - residual magnetic intensity
DS1982-0073
1982
Guiness, E.A.Arvidson, R.E., Guiness, E.A., Strebeck, J.W., Davies, G.F.Image Processing Applied to Gravity and Topography Dat a Covering the Continental United States (us)Eos, Vol. 63, No. 18, MAY 4TH. PP. 261-265.GlobalMid Continent
DS1983-0111
1983
Guiness, E.A.Arvidson, R.E., Guiness, E.A., Leff, C.E.New Perspectives on the Crustal Structure of MissouriGeological Society of America (GSA), Vol. 15, No. 6, P. 517. (abstract.).GlobalMid Continent
DS1981-0069
1981
Guinness, E.A.Arvidson, R.E., Guinness, E.A.Integration of Remote Sensing, Geophysical and Geological Dat a Sets to Better Understand the Structural Geology of the St. Francois MountainsInstitute ELECTR. ELECTRON. ENG., Symposium Vol., PP. 895-896.GlobalMid-continent
DS1982-0074
1982
Guinness, E.A.Arvidson, R.E., Guinness, E.A., Strebeck, J.W.Structure of the Mid-continent Basement: Topography, Gravity,seismic and Remote Sensing Data.Cospar Plenary Meet. Program Abstracts, Vol. 24, P. 87. (abstract.).GlobalMid-continent
DS1982-0229
1982
Guinness, E.A.Guinness, E.A., Arvidson, R.E., et al.Identification of a Precambrian Rift through Missouri by Digital Image Processing of Geophysical and Geological Data.Journal of GEOPHYSICAL RESEARCH, Vol. 87, No. B10, Oct. 10, PP. 8529-8546.GlobalMid-continent
DS1983-0112
1983
Guinness, E.A.Arvidson, R.E., Guinness, E.A., Bindschadler, D.L.Structure of the St. Francois Mountains and Surrounding Lead Belt Southeast Missouri: Inferences from Thermal Infrared and Other Dat a Sets.Nasa National Technical Information Service Final Report., No. E84-10027, 78P.United States, MissouriMid Continent
DS200612-0510
2006
Guirand, M.Guirand, M., Powell, R.P V T relationships and mineral equilibration temperatures in inclusions in minerals.Earth and Planetary Science Letters, Vol. 244, 3-4, Apr.30, pp. 683-694.TechnologyDiamond, coesite, mineral inclusions
DS2001-0311
2001
Guiraud, M.Fabries, J., Lorand, J.P., Guiraud, M.Petrogenesis of the amphibole rich veins from the Lherz orogenic lherzolite massif: case study lithospheric...Contributions to Mineralogy and Petrology, Vol. 140, No. 4, pp. 383-403.France, mantlePyroxenites, Petrology
DS1997-0455
1997
Guiraud, R.Guiraud, R., Bosworth, W.Senonian basin inversion and rejuvenation of rifting in Africa and Arabia:synthesis and implications -Tectonophysics, Vol. 282, No. 1-4, Dec. 15, pp. 1-38.AfricaTectonics - plate scale, Rifting
DS2000-0367
2000
Guiraud, R.Guiraud, R., Bosworth, W.Phanerozoic geodynamic evolution of northeastern Africa and the northwestern Arabian PlatformTectonophysics, Vol. 315, No. 1-4, Dec. 31, pp. 73-108.Africa, ArabiaGeodynamics, Craton
DS2000-0368
2000
Guiraud, R.Guiraud, R., Doumnang Mbaigne, J-C.Evidence for a 6000 km length northwest -southeast striking lineament in northern Africa: the Tibesti lineament.Journal of Geological Society of London, Vol. 157, No. 5, Sept.pp. 897-900.Africa, north, Egypt, SudanStructure, Lineaments
DS2001-0726
2001
GuiseManhica, A.S.T.D., Grantham, Armstrong, Guise, KrugerPolyphase deformation and metamorphism at the Kalahari Craton - Mozambique Belt boundary.Geological Society of London, Special Publication, Special Paper 184, pp. 303-22.South Africa, MozambiqueMetamorphism, Craton
DS1998-0933
1998
Guise, P.D.Manhica, A., Grantham, G.H., Guise, P.D.An 40Ar 39Ar study of Zimbabwe Craton Mozambique Belt boundary inManica-Chimoio area, western Mozambique.Journal of African Earth Sciences, Vol. 27, 1A, p. 135. AbstractGlobalGeochronology
DS1995-0825
1995
Guitang, P.Hsu, K.J., Guitang, P., Winterer, E.L.Tectonic evolution of the Tibetan Plateau: a working hypothesis based In the Archipelago model of orogenesisInternational Geology Review, Vol. 37, No. 6, June 1, pp. 473-525.ChinaTectonics, Tibetan Plateau
DS1995-0826
1995
Guitang, P.Hsu, K.J., Guitang, P., Winterer, E.L.Tectonic evolution of the Tibetan Plateau: a working hypothesis based on the Archipelago model orogenesisInternational Geology Review, Vol. 37, No. 6, June, pp. 473-525ChinaTectonics, Tibetan Plateau
DS201212-0267
2012
Guitarrari Azzone, R.Guarino, V., Guitarrari Azzone, R., Brotzu, P., Celso de Barros Gomes, Melluso, L., Morbidelli, L.,Ruberti, E.,Tassinari, C., Brilli, M.Magmatism and fenitization in the Cretaceous potassium-alkaline-carbonatitic complex of Ipanema Sao Paulo State, Brazil.Mineralogy and Petrology, Vol. 104, 1-2, pp. 43-61.South America, BrazilCarbonatite
DS201012-0012
2010
Guitreau, M.Arndt, N.T., Guitreau, M., Boullier, A-M., Le Roex, A., Tommasi, A.M., Cordier, P., Sobolev, A.Olivine, and the origin of kimberlite.Journal of Petrology, Vol. 51, 3, pp. 573-602.TechnologyKimberlite genesis
DS201905-1018
2019
Guitreau, M.Bohm, C.O., Hartlaub, R.P., Heaman, L.M., Cates, N., Guitreau, M., Bourdon, B., Roth, A.S.G., Mojzsis, S.J., Blichert-Toft, J.The Assean Lake Complex: ancient crust at the northwestern margin of the Superior Craton, Manitoba, Canada.Earths Oldest Rocks, researchgate.com Chapter 28, 20p. Pdf availableCanada, Manitobacraton

Abstract: This chapter describes the Assean Lake Complex (ALC) at ancient crust at the Northwestern margin of the Superior Craton, Manitoba, and Canada. An initial tectonic model for the Assean Lake area indicated that a regionally extensive high-strain zone running through the lake marks the suture between Archean high-grade crustal terranes of the Superior Craton to the southeast and Paleoproterozoic rocks of the Trans-Hudson Orogen to the northwest. Detailed geologic remapping combined with isotopic and geochemical studies led to a re-interpretation of the crust immediately north of the Assean Lake high-strain zone as Mesoarchean. The study area straddles the boundary between the Archean Superior Craton and the ca.1.90-1.84 Ga arc and marginal basin rocks of the Trans-Hudson Orogen, which represent the remains of ca. 1.83-1.76 Ga ocean closure and orogeny. It is indicated that the gneisses of the Split Lake Block consist primarily of meta-igneous protoliths of gabbroic to granitic composition. Tonalite and granodiorite are the most volumetrically dominant, but an anorthosite dome is also present in the northeast. Mapping, isotopic, and age data combined with high-resolution aero-magnetic data indicate that the Mesoarchean ALC is a crustal slice up to 10 km wide, and has a strike length of at least 50 km.
DS202002-0167
2019
Guitreau, M.Bohm, C.O., Hartlaub, R.P., Heaman, L.M., Cates, N., Guitreau, M., Bourdon, B., Roth, A.S.G., Mojzsis, S.J., Blichert-Toft, J.The Assean Lake Complex: ancient crust at the northwestern margin of the Superior craton, Manitoba, Canada. ( not specific to diamonds)Earth's Oldest Rocks, Chapter 28, 20p. Pdf.Canada, Manitobacraton
DS202008-1399
2020
Gukurume, S.Gukurume, S., Nhodo, L.Forced displacements in mining communities: politics in Chiadzwa diamond area, Zimbabwe.Journal of Contemporary African Studies, Vol. 38, 1, pp. 39-54.Africa, Zimbabwedeposit - Chiadzwa

Abstract: The Chiadzwa diamonds attracted widespread attention due to human rights violations and illegal smuggling. When diamonds were discovered in 2006, thousands of artisanal miners descended on the diamond fields. In response, the government unleashed the army and police in brutal crackdowns to drive artisanal miners off the diamond fields. This militarisation of diamond fields and extraction was followed by forced displacement of the Chiadzwa people. This article examines the lived, everyday experiences of the displaced Chiadzwa people. Findings reveal that displacements dislocated the livelihoods and socialities of the people. Displacements also exacerbated people's vulnerability to livelihood shocks, insecurity, and poverty. In relocating people the government adopted a ‘top-down’ approach which triggered contestations and conflicts with the people who felt alienated from their ancestral land and excluded from diamond wealth. Consequently, sabotage, resistance and subversion were commonplace in the relocation process. These socio-political ‘tactics’ should be viewed as ‘weapons of the weak’.
DS201412-0341
2014
Gule, N.Harris, C., Hlongwane, W., Gule, N., Scheepers, R.Origin of tanzanite and associated gemstone mineralization at Merlani, Tanzania.Journal of South African Geology, Vol. 117, 1, June pp. 15-30.Africa, TanzaniaTanzanite
DS1997-1261
1997
Gulec, N.Wilson, M., Tankut, A., Gulec, N.Tertiary volcanism of the Galatia province, northwest central AnatoliaTurkeyLithos, Vol. 42, No. 1-2, Dec. 1, pp. 105-122Globalvolcanism.
DS1988-0291
1988
Gulen, L.Hart, S.R., Gulen, L.Crust/Mantle recycling at convergent zonesD. Reidel Publishing Co., Nato Series, Asi C, Math. Phys. Sci., Vol. 258, 280p. approx. $ 80.00 United StatesGlobalMantle, Book -Table of contents
DS201312-0345
2013
Gulick, S.P.S.Gulick, S.P.S., Christeson, G.L., Barton, P.J., Grieve, R.A.F., Morgan, J.V., Urrutia-Fucugauchi, J.Geophysical characterization of the Chicxulub impact crater.Reviews of Geophysics, Vol. 51, 1, pp. 31-52.United States, MexicoMeteorite
DS201312-0430
2013
Gulick, V.C.Ishikawa, S.T., Gulick, V.C.An automated mineral classifer using Raman spectra. ( igneous rocks)Computers & Geosciences, Vol. 54, pp. 259-268.TechnologySpectral data
DS200612-1150
2006
GulievReilinger, R., McClusky, S., Vernant, P., Lawrence, S., Ergintav, Cakmak, Ozener, Kadirov, Guliev, StepanyanGPS constraints on continental deformation in the Africa Arabia Eurasia continental collision zone and implications for the dynamics of plate interactions.Journal of Geophysical Research, Vol. 111,B5 B05411.AfricaGeodynamics
DS1990-0552
1990
Guliov, P.Gent, M.R., Harper, C.T., Guliov, P., Macdonald, R.Saskatchewan diamonds: a new realityThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 83, No. 939, July p. 115. Abstract (PDA)SaskatchewanBrief overview, Diamond activities
DS1991-0624
1991
Guliov, P.Guliov, P.Overview of industrial minerals in Saskatchewan. Brief 1/2 page mention ofdiamondsBritish Columbia Geological Survey, Open File, No. 1991-23, p. 31SaskatchewanBrief mention, Diamonds
DS1995-0697
1995
Guliy, V.N.Guliy, V.N.Main features of composition and origin of apatite deposits in metamorphic rocks of the Aldan Shield.Transactions of the Institute of Mining and Metallurgy (IMM)., Vol. 104, pp. B171-B178.Russia, Aldan shieldAlkaline rocks
DS1989-0760
1989
Gulko, N.I.Kepezhinskas, P.K., Gulko, N.I., Yefremova, L.B.Geochemistry of rare earth elements in the Paleogenesho shonite of the southern Koryak HighlandsInternational Geology Review, Vol. 31, No. 4, April pp. 343-352RussiaShoshonite, Geochemistry
DS1994-0483
1994
Gulliver, C.B.Edgar, A.D., Mitchell, R.H., Gulliver, C.B.New mineral species found in experiments at continental mantle pressures(2-8 GPa) in kimberlite and lamproiteInternational Symposium Upper Mantle, Aug. 14-19, 1994, Extended abstracts pp. 19-20.MontanaMineralogy, Deposit -Smoky Butte
DS1995-0698
1995
Gulliver, C.E.Gulliver, C.E., Edgar, A.D.New potential mantle reservoirs for incompatible and volatiles and role genesis of ultrapotassioc magmas.Geological Society Africa 10th. Conference Oct. Nairobi, p. 116. Abstract.GlobalUltrapotassic magmas, Lamproites, lamprophyres, kamafugites, kimberlites
DS1994-0673
1994
Gulliver, C.G.Gulliver, C.G., Edgar, A.D.Alternate reservoirs for Potassium, Barium, Titanium, Flourine and Phosphorus in the enriched continental mantle.Geological Association of Canada (GAC) Abstract Volume, Vol. 19, p.MantleAlkaline rocks
DS2001-1129
2001
GulserenSteinle-Neumann, G., Stixrude, Cohen, R.E., GulserenElasticity of iron at the temperature of the Earth's inner coreNature, Vol. 413, Sept. 6, pp. 57-60.MantleGeophysics - seismics
DS1992-0629
1992
Gulson, B.Gulson, B.The status of vapour geochemistryExplore, No. 74, January pp. 6, 8, 9, 10AustraliaGeochemistry, Overview of vapour geochemistry
DS1991-0625
1991
Gulson, B.L.Gulson, B.L., Solomon, M., Vaasjoki, M., Both, R.Tasmania adrift?Australian Journal of Earth Sciences, Vol. 38, pp. 249-250TasmaniaTectonics, Structure
DS1990-0611
1990
Gummer, P.K.Gummer, P.K., McGowan, S.E., Halabura, S.P.Diamond exploration at Prince Albert, Saskatchewan, CanadaAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Meeting, Salt Lake City, February 26, Non speaker/no preprintSaskatchewanExploration, Overview
DS1993-1138
1993
Gummer, P.K.Nixon, P.H., Gummer, P.K., Halabura, S., Leahy, K., Finlay, S.Kimberlites of volcanic facies in the Sturgeon Lake areaRussian Geology and Geophysics, Vol. 34, No. 12, pp. 66-76.SaskatchewanVolcanic facies
DS201811-2605
2018
Gumsley, A.Salminen, J., Hanson, R., Evans, D.A.D., Gong, Z., Larson, T., Walker, O., Gumsley, A., Soderlund, U., Ernst, T.Direct Mesoproterozoic connection of the Congo and Kalahari cratons in proto-Africa: strange attractors across supercontinental cycles.Geology, doi.org/10.1130/G45294.1 4p.Africacraton

Abstract: Mobilistic plate-tectonic interpretation of Precambrian orogens requires that two conjoined crustal blocks may derive from distant portions of the globe. Nonetheless, many proposed Precambrian cratonic juxtapositions are broadly similar to those of younger times (so-called “strange attractors”), raising the specter of bias in their construction. We evaluated the possibility that the Congo and Kalahari cratons (Africa) were joined together prior to their amalgamation along the Damara-Lufilian-Zambezi orogen in Cambrian time by studying diabase dikes of the Huila-Epembe swarm and sills in the southern part of the Congo craton in Angola and in Namibia. We present geologic, U-Pb geochronologic, and paleomagnetic evidence showing that these two cratons were directly juxtaposed at ca. 1.1 Ga, but in a slightly modified relative orientation compared to today. Recurring persistence in cratonic connections, with slight variations from one supercontinent to the next, may signify a style of supercontinental transition similar to the northward motion of Gondwana fragments across the Tethys-Indian oceanic tract, reuniting in Eurasia.
DS201902-0316
2019
Gumsley, A.Salminen, J., Hanson, R., Evans, D.A.D., Gong, Z., Larson, T., Walker, O., Gumsley, A., Soderlund, U., Ernst, R.Direct Mesoproterozoic connection of the Congo and Kalahari cratons in proto-Africa: strange attractors across supercontinental cycles.Geology, Vol. 46, pp. 1101-1104.Africa, Angola, Namibiacraton

Abstract: Mobilistic plate-tectonic interpretation of Precambrian orogens requires that two conjoined crustal blocks may derive from distant portions of the globe. Nonetheless, many proposed Precambrian cratonic juxtapositions are broadly similar to those of younger times (so-called “strange attractors”), raising the specter of bias in their construction. We evaluated the possibility that the Congo and Kalahari cratons (Africa) were joined together prior to their amalgamation along the Damara-Lufilian-Zambezi orogen in Cambrian time by studying diabase dikes of the Huila-Epembe swarm and sills in the southern part of the Congo craton in Angola and in Namibia. We present geologic, U-Pb geochronologic, and paleomagnetic evidence showing that these two cratons were directly juxtaposed at ca. 1.1 Ga, but in a slightly modified relative orientation compared to today. Recurring persistence in cratonic connections, with slight variations from one supercontinent to the next, may signify a style of supercontinental transition similar to the northward motion of Gondwana fragments across the Tethys-Indian oceanic tract, reuniting in Eurasia.
DS1960-0554
1965
Gunaratane, H.S.Gunaratane, H.S.The Discovery of a Diamond from CeylonSpolia Zeylanica., Vol. 30, PT. 2, P.Sri LankaDiamond Occurrences
DS1995-1295
1995
Gunderson, R.P.Moore, J.N., Gunderson, R.P.Fluid inclusion and isotopic systematics of an evolving magmatic-hydrothermal systemGeochimica et Cosmochimica Acta, Vol. 59, No. 19, Oct. 1, pp. 3887-3908MantleMagmatism, system
DS1994-1651
1994
Gundobin, A.G.Sobachenko, V.N., Gundobin, A.G., Sandimirova, G.P., et al.Strontium isotopes in the rocks of formational type of near fault alkaline carbonate silicate metasomatites.Russian Geology and Geophysics, Vol. 35, No. 3, pp. 51-58.Russia, Urals, YeniseiGeochronology, Carbonatite
DS201412-0223
2014
Gundogan, I.Ersoy, Y.E., Palmer, M.R., Uysal, I., Gundogan, I.Geochemistry and petrology of the Early Miocene lamproites and related volcanic rocks in the Thrace basin, NW Anatolia.Journal of Volcanology and Geothermal Research, Vol. 283, pp. 143-158.Europe, TurkeyLamproite
DS202103-0384
2021
Gunduz, M.Gunduz, M., Asan, K.PetroGram: an excel-based petrology program for modeling of magmatic processes.Geoscience Frontiers, Vol. 12, pp. 81-92. pdfGlobalpetrology

Abstract: PetroGram is an Excel© based magmatic petrology program that generates numerical and graphical models. PetroGram can model the magmatic processes such as melting, crystallization, assimilation and magma mixing based on the trace element and isotopic data. The program can produce both inverse and forward geochemical models for melting processes (e.g. forward model for batch, fractional and dynamic melting, and inverse model for batch and dynamic melting). However, the program uses a forward modeling approach for magma differentiation processes such as crystallization (EC: Equilibruim Crystallization, FC: Fractional Crystallization, IFC: Imperfect Fractional Crystallization and In-situ Crystallization), assimilation (AFC: Assimilation Fractional Crystallization, Decoupled FC-A: Decoupled Fractional Crystallization and Assimillation, A-IFC: Assimilation and Imperfect Fractional Crystallization) and magma mixing. One of the most important advantages of the program is that the melt composition obtained from any partial melting model can be used as a starting composition of the crystallization, assimilation and magma mixing. In addition, PetroGram is able to carry out the classification, tectonic setting, multi-element (spider) and isotope correlation diagrams, and basic calculations including Mg#, Eu/Eu?, ?Sr and ?Nd widely used in magmatic petrology.
DS201212-0270
2012
Guneralp, I.Guneralp, I., Abad, J.D., Zolezzi, G., Hooke, J.Advances and challenges in meandering channels research.Geomorphology, Vol. 163-164, pp. 1-9.TechnologyMeandering channels - issue (not specific to diamonds)
DS2002-1357
2002
Gung, Y.Romanowicz, B., Gung, Y.Superplumes from the core mantle boundary to the lithosphere: implications for heat flux.Science, No. 5567, April 19,pp.513-5., No. 5567, April 19,pp.513-5.MantlePlumes - hot spots, Geothermometry
DS2002-1358
2002
Gung, Y.Romanowicz, B., Gung, Y.Superplumes from the core mantle boundary to the lithosphere: implications for heat flux.Science, No. 5567, April 19,pp.513-5., No. 5567, April 19,pp.513-5.MantlePlumes - hot spots, Geothermometry
DS2003-0519
2003
Gung, Y.Gung, Y., Panning, M., Robanowicz, B.Global anisotropy and the thickness of continentsNature, No. 6933, April 17, p. 707-710.MantleGeophysics
DS2003-0520
2003
Gung, Y.Gung, Y., Panning, M., Romanowicz, B.Global anisotropy and the thickness of continentsNature, Vol. 422, April 17. pp. 707-711.MantleGeophysics - seismics
DS200412-0743
2003
Gung, Y.Gung, Y., Panning, M., Romanowicz, B.Global anisotropy and the thickness of continents.Nature, Vol. 422, April 17. pp. 707-711.MantleGeophysics - seismics
DS200412-0744
2004
Gung, Y.Gung, Y., Romanowicz, B.Q tomography of the upper mantle using three component long period waveforms.Geophysical Journal International, Vol. 157, 2, pp. 813-830.MantleGeophysics - seismics
DS201212-0122
2012
GunnChambers, J.E., Wilkinson, P.B., Wardrop, D., Hameed, A., Hill, L., Jeffrey, C., Loke, Mledrum, Kuras, Cave, GunnBedrock detection beneath river terrace deposits using three dimensional electrical resistivity tomography.Geomorphology, Vol. 177-178, pp. 7-25.TechnologyTomography - not specific to diamonds
DS201512-1904
2015
Gunn, A.Chen, W., Leblanc, S.G., White, H.P., Milkovic, B., O'Keefe, H., Croft, B., Gunn, A., Boulanger, J.Caribou relevant environmental changes around the Ekati diamond mine measured in 2015.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 24.Canada, Northwest TerritoriesDeposit - Ekati

Abstract: How would a large open pit mine on caribou range (e.g., the Ekati Diamond Mine in the Bathurst caribou’s summer range) have influenced caribou? A traditional knowledge study on the cumulative impacts on the Bathurst caribou herd qualitatively described how mining activities might have influenced the herd (Mackenzie et al. 2013): caribou migration routes deflected away from the mines probably due to seeing mining activities or hearing the noises; and skinny caribou or abnormal smells and materials in caribou meat, liver, or the hide linings probably related to changes in caribou forage and quality of water and air. In other words, the potential influences of mining operations on caribou were most likely through altering what caribou can see, hear, smell (e.g., dusts and fine particle matter < 2.5 ?m (PM2.5) in the air, and from acidity in the soil), and taste (e.g., dust on foliage, vegetation composition change). Boulanger et al. (2012) estimated the size of a zone of influence (ZOI) of the Ekati-Diavik mining complex in the Bathurst caribou summer range, using caribou presence dataset. They also explored the mechanisms of ZOI using the spatial distribution of the total suspended particles, which was simulated with an atmospheric transport and dispersion model (Rescan, 2006). While these studies have added to our understanding of the possible impacts of mining operations on caribou, knowledge gaps remain. One outstanding gap is the lack of direct measurements about the caribou relevant environmental changes caused by mining operations. For example, exactly from how far away can caribou clearly see the vehicles driving on a mining road, or the buildings and the elevated waste piles in a camp? From how far away might caribou hear the noise caused by mining operations? To what spatial extent had the dusts and PM2.5 from mining operations influenced the tundra ecosystems? And how the dusts and PM2.5 from mining operations might have influenced caribou forage quality? Potentially these questions can be answered by in-situ measurements and satellite remote sensing. For example, studies have showed that it is possible to remotely sense PM2.5 distribution using twice-daily MODIS data at a spatial resolution of 1 km (Lyapustin et al., 2011; Chudnovsky et al., 2013; Hu et al., 2014). The objective of this study is thus to quantitatively measure these changes around the Ekati Diamond Mine, by means of in-situ surveys and satellite remote sensing. We conducted field surveys at more than 100 sites around the Ekati Diamond Mine during August 14-23, 2015, a collaborative effort of the NWT CIMP project entitled “Satellite Monitoring for Assessing Resource Development’s Impact on Bathurst Caribou (SMART)”, and the Dominion Diamond Ekati Corporation. In this presentation, we will report preliminary results and lessons learned from our first year’s study.
DS1995-1723
1995
Gunn, A.G.Shaw, M.H., Gunn, A.G.platinum group elements (PGE) exploration in the alkaline intrusions of northwest ScotlandProspectors and Developers Association of Canada (PDAC) Reprint, 6pScotlandAlkaline rocks, PlatinuM.
DS201809-2032
2018
Gunn, A.G.Gunn, A.G., Dorbor, J.K., Mankelow, J.M., Lusty, P.A.J., Deady, E.A., Shaw, R.A.A review of the mineral potential of Liberia.Ore Geology Reviews, Vol. 101, pp. 413-431.Africa, Liberiadiamonds

Abstract: The Republic of Liberia in West Africa is underlain mostly by Precambrian rocks of Archaean (Liberian) age in the west and of Proterozoic (Eburnean) age in the east. By analogy with similar terranes elsewhere in the world, and in West Africa in particular, the geology of Liberia is favourable for the occurrence of deposits of a wide range of metals and industrial minerals, including gold, iron ore, diamonds, base metals, bauxite, manganese, fluorspar, kyanite and phosphate. Known gold deposits, mostly orogenic in style, occur widely and are commonly associated with north-east-trending regional shear zones. Gold mining commenced at the New Liberty deposit in western Liberia in 2015, while significant gold resources have also been identified at several other sites in both Archaean and Proterozoic terranes. Liberia has large resources of itabirite-type iron ores, most of which are located in the Liberian terrane, and was the largest producer in Africa prior to the onset of civil war in 1989. Production of iron ore is currently restricted to a single mine, Yekepa, in the Nimba Range. Other important deposits, some of them previously mined, include Bong, the Western Cluster, Putu and Goe Fantro. There is a long history of alluvial diamond production in western and central Liberia, together with more than 160 known occurrences of kimberlite. Most of the known kimberlites occur in three clusters of small pipes and abundant dykes, located at Kumgbor, Mano Godua and Weasua, close to the border with Sierra Leone. Many of these are considered to be part of a single province that includes Jurassic age diamondiferous kimberlites in Sierra Leone and Guinea. Deposits and occurrences of a wide range of other metals and industrial minerals are also known. Several of these have been worked on a small scale in the past, mainly by artisanal miners, but most are poorly known in detail with sub-surface information available at only a few localities. By comparison with most other countries in West Africa, the geology of Liberia is poorly known and there has been very little systematic exploration carried out for most commodities other than gold, iron ore and diamonds since the 1960s and 1970s. Further detailed field and laboratory investigations using modern techniques are required to properly evaluate the potential for the occurrence of economic deposits of many minerals and metals in a variety of geological settings. Digital geological, geochemical, geophysical and mineral occurrence datasets, including new national airborne geophysical survey data, provide a sound basis for the identification of new exploration targets, but in almost every part of the country there is a need for new and more detailed geological surveys to underpin mineral exploration.
DS1960-0833
1967
Gunn, C.B.Gunn, C.B.Provenance of Diamonds in the Glacial Drift of the Great Lakes Region, North America.London: Msc. Thesis, University Western Ontario, 132P.United States, Great Lakes, Canada, OntarioGeomorphology, Diamond Occurrences
DS1960-0834
1967
Gunn, C.B.Gunn, C.B.The Origin of Diamonds in Drift of the North Central Unitedstates: a Discussion.Journal of GEOLOGY, Vol. 75, No. 2, PP. 232-233.United States, Great Lakes, Canada, Ontario, Wisconsin, MichiganOrigin
DS1960-0956
1968
Gunn, C.B.Gunn, C.B.A Descriptive Catalog of the Drift Diamonds of the Great Lakes Region, North America.Gems And Gemology, SUMMER PP. 297-302.; FALL PP. 333-345.United States, Great Lakes, Canada, OntarioDiamonds Notable, Occurrences
DS1960-0957
1968
Gunn, C.B.Gunn, C.B.Diamond Prospecting in LiberiaLapidary Journal, Vol. 22, No. 1, PP. 130-132.; No. 2, PP. 134-136.West Africa, LiberiaProspecting
DS201312-0144
2013
Gunn, D.A.Chambers, J.E., Wilkinson, P.B., Wrdrop, D., Hameed, A., Hill, I., Jeffrey, C., Loke, M.H., Meldrum, P.I., Kuras, O., Cave, M., Gunn, D.A.Bedrock detection beneath river terrace deposits using three dimensional electrical resistivity tomography.Geomorphology, Vol. 177-178, pp. 17-25.GlobalGeochronology
DS200612-0511
2006
Gunn, D.C.Gunn, D.C., Luth, R.W.Carbonate reduction by Fe-S-O melts at high pressure and high temperature.American Mineralogist, Vol. 91, July pp. 1110-1116.TechnologyPetrology, UHP, crystal synthesis, diamond
DS201604-0595
2016
Gunn, G.Broom-Fendley, S., Styles, M.T., Appleton, J.D., Gunn, G., Wall, F.Evidence for dissolution reprecipitation of apatite and preferential LREE mobility in carbonatite derived late stage hydrothermal processes.American Mineralogist, Vol. 101, pp. 596-611.Africa, MalawiCarbonatite

Abstract: The Tundulu and Kangankunde carbonatite complexes in the Chilwa Alkaline Province, Malawi, contain late-stage, apatite-rich lithologies termed quartz-apatite rocks. Apatite in these rocks can reach up to 90 modal% and displays a distinctive texture of turbid cores and euhedral rims. Previous studies of the paragenesis and rare earth element (REE) content of the apatite suggest that heavy REE (HREE)-enrichment occurred during the late-stages of crystallization. This is a highly unusual occurrence in intrusions that are otherwise light REE (LREE) enriched. In this contribution, the paragenesis and formation of the quartz-apatite rocks from each intrusion is investigated and re-evaluated, supported by new electron microprobe (EPMA) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) data to better understand the mechanism of HREE enrichment. In contrast to the previous work at Tundulu, we recognize three separate stages of apatite formation, comprising an “original” euhedral apatite, “turbid” apatite, and “overgrowths” of euhedral late apatite. The crystallization of synchysite-(Ce) is interpreted to have occurred subsequent to all phases of apatite crystallization. The REE concentrations and distributions in the different minerals vary, but generally higher REE contents are found in later-stage apatite generations. These generations are also more LREE-enriched, relative to apatite that formed earlier. A similar pattern of increasing LREE-enrichment and increased REE concentrations toward later stages of the paragenetic sequence is observed at Kangankunde, where two generations of apatite are observed, the second showing higher REE concentrations, and relatively higher LREE contents. The changing REE distribution in the apatite, from early to late in the paragenetic sequence, is interpreted to be caused by a combination of dissolution-reprecipitation of the original apatite and the preferential transport of the LREE complexes by F- and Cl-bearing hydrothermal fluids. Successive pulses of these fluids transport the LREE out of the original apatite, preferentially re-precipitating it on the rim. Some LREE remained in solution, precipitating later in the paragenetic sequence, as synchysite-(Ce). The presence of F is supported by the F content of the apatites, and presence of REE-fluorcarbonates. Cl is not detected in the apatite structure, but the role of Cl is suggested from comparison with apatite dissolution experiments, where CaCl2 or NaCl cause the reprecipitation of apatite without associated monazite. This study implies that, despite the typically LREE enriched nature of carbonatites, significant degrees of hydrothermal alteration can lead to certain phases becoming residually enriched in the HREE. Although at Tundulu the LREE-bearing products are re-precipitated relatively close to the REE source, it is possible that extensive hydrothermal activity in other carbonatite complexes could lead to significant, late-stage fractionation of the REE and the formation of HREE minerals.
DS201609-1707
2016
Gunn, G.Broom-Fendley, S., Heaton, T., Wall, F., Gunn, G.Tracing the fluid source of heavy REE mineralization in carbonatites using a novel method of oxygen isotope analysis in apatite: the example of Songwe Hill, Malawi.Chemical Geology, Vol. 440, pp. 275-287.Africa, MalawiCarbonatite

Abstract: Stable (C and O) isotope data from carbonates are one of the most important methods used to infer genetic processes in carbonatites. However despite their ubiquitous use in geological studies, it is suspected that carbonates are susceptible to dissolution-reprecipitation and isotopic resetting, especially in shallow intrusions, and may not be the best records of either igneous or hydrothermal processes. Apatite, however, should be much less susceptible to these resetting problems but has not been used for O isotope analysis. In this contribution, a novel bulk-carbonatite method for the analysis of O isotopes in the apatite PO4 site demonstrates a more robust record of stable isotope values. Analyses of apatite from five carbonatites with magmatic textures establishes a preliminary Primary Igneous Apatite (PIA) field of ?18O = + 2.5 to + 6.0‰ (VSMOW), comparable to Primary Igneous Carbonatite (PIC) compositions from carbonates. Carbonate and apatite stable isotope data are compared in 10 carbonatite samples from Songwe Hill, Malawi. Apatite is heavy rare earth element (HREE) enriched at Songwe and, therefore, oxygen isotope analyses of this mineral are ideal for understanding HREE-related mineralisation in carbonatites. Carbonate C and O isotope ratios show a general trend, from early to late in the evolution, towards higher ?18O values (+ 7.8 to + 26.7‰, VSMOW), with a slight increase in ?13C (? 4.6 to ? 0.1‰, VPDB). Oxygen isotope ratios from apatite show a contrary trend, decreasing from a PIA field towards more negative values (+ 2.5 to ? 0.7‰, VSMOW). The contrasting results are interpreted as the product of the different minerals recording fluid interaction at different temperatures and compositions. Modelling indicates the possibility of both a CO2 rich fluid and mixing between meteoric and deuteric waters. A model is proposed where brecciation leads to depressurisation and rapid apatite precipitation. Subsequently, a convection cell develops from a carbonatite, interacting with surrounding meteoric water. REE are likely to be transported in this convection cell and precipitate owing to decreasing salinity and/or temperature.
DS201701-0004
2016
Gunn, G.Broom-Fendley, S., Brady, A.E., Wall, F., Gunn, G., Dawes, W.REE minerals at the Songwe Hill carbonatite, Malawi: HREE enrichment in late stage apatite.Ore Geology Reviews, Vol. 81, pp. 23-41.Africa, MalawiCarbonatite

Abstract: Compared to all published data from carbonatites and granitoids, the fluorapatite compositions in the Songwe Hill carbonatite, determined by EPMA and LA ICP-MS, have the highest heavy (H)REE concentration of any carbonatite apatite described so far. A combination of this fluorapatite and the REE fluorocarbonates, synchysite-(Ce) and parisite-(Ce), which are the other principal REE bearing minerals at Songwe, gives a REE deposit with a high proportion of Nd and a higher proportion of HREE (Eu-Lu including Y) than most other carbonatites. Since Nd and HREE are currently the most sought REE for commercial applications, the conditions that give rise to this REE profile are particularly important to understand. Multiple apatite crystallisation stages have been differentiated texturally and geochemically at Songwe and fluorapatite is divided into five different types (Ap-0-4). While Ap-0 and Ap-1 are typical of apatite found in fenite and calcite-carbonatite, Ap-2, -3 and -4 are texturally atypical of apatite from carbonatite and are progressively HREE-enriched in later paragenetic stages. Ap-3 and Ap-4 exhibit anhedral, stringer-like textures and their REE distributions display an Y anomaly. These features attest to formation in a hydrothermal environment and fluid inclusion homogenisation temperatures indicate crystallisation occurred between 200-350 °C. Ap-3 crystallisation is succeeded by a light (L)REE mineral assemblage of synchysite-(Ce), strontianite and baryte. Finally, late-stage Ap-4 is associated with minor xenotime-(Y) mineralisation and HREE-enriched fluorite. Fluid inclusions in the fluorite constrain the minimum HREE mineralisation temperature to approximately 160 °C. A model is suggested where sub-solidus, carbonatite-derived, (carbo)-hydrothermal fluids remobilise and fractionate the REE. Chloride or fluoride complexes retain LREE in solution while rapid precipitation of apatite, owing to its low solubility, leads to destabilisation of HREE complexes and substitution into the apatite structure. The LREE are retained in solution, subsequently forming synchysite-(Ce). This model will be applicable to help guide exploration in other carbonatite complexes.
DS201707-1310
2017
Gunn, G.Broom-Fendley, S., Brady, A.E., Horstwood, M.S.A., Woolley, A.R., Mtegha, J., Wall, F., Dawes, W., Gunn, G.Geology, geochemistry and geochronology of the Songwe Hill carbonatite, Malawi.Journal of African Earth Sciences, Vol. 134, pp. 10-23.Africa, Malawicarbonatite - Songwe Hill

Abstract: Songwe Hill, Malawi, is one of the least studied carbonatites but has now become particularly important as it hosts a relatively large rare earth deposit. The results of new mapping, petrography, geochemistry and geochronology indicate that the 0.8 km diameter Songwe Hill is distinct from the other Chilwa Alkaline Province carbonatites in that it intruded the side of the much larger (4 x 6 km) and slightly older (134.6 ± 4.4 Ma) Mauze nepheline syenite and then evolved through three different carbonatite compositions (C1–C3). Early C1 carbonatite is scarce and is composed of medium–coarse-grained calcite carbonatite containing zircons with a U–Pb age of 132.9 ± 6.7 Ma. It is similar to magmatic carbonatite in other carbonatite complexes at Chilwa Island and Tundulu in the Chilwa Alkaline Province and others worldwide. The fine-grained calcite carbonatite (C2) is the most abundant stage at Songwe Hill, followed by a more REE- and Sr-rich ferroan calcite carbonatite (C3). Both stages C2 and C3 display evidence of extensive (carbo)-hydrothermal overprinting that has produced apatite enriched in HREE (<2000 ppm Y) and, in C3, synchysite-(Ce). The final stages comprise HREE-rich apatite fluorite veins and Mn-Fe-rich veins. Widespread brecciation and incorporation of fenite into carbonatite, brittle fracturing, rounded clasts and a fenite carapace at the top of the hill indicate a shallow level of emplacement into the crust. This shallow intrusion level acted as a reservoir for multiple stages of carbonatite-derived fluid and HREE-enriched apatite mineralisation as well as LREE-enriched synchysite-(Ce). The close proximity and similar age of the large Mauze nepheline syenite suggests it may have acted as a heat source driving a hydrothermal system that has differentiated Songwe Hill from other Chilwa carbonatites.
DS1995-0699
1995
Gunn, J.M.Gunn, J.M.Restoration and recovery of an industrial region... progress in SudburyareaSpringer, 350p. Cost ?OntarioBook -table of contents, Environment, emissions, Sudbury area
DS1986-0316
1986
Gunn, M.J.Gunn, M.J., Edwards, A.C., Paterson, D.A., Ringenbergs, W.H.Origin of the Casurain a alluvial diamonds, western AustraliaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 463-465AustraliaDiamond exploration
DS1995-1724
1995
Gunn, P.Shaw, R.D., Wellman, P., Gunn, P., Whitaker, A.J., et al.Australian crustal elements map: a geophysical model for the tectonic framework of the continentAgso Research Newsletter, No. 23, Nov. pp. 1-3. Scale 1:5 M.AustraliaMap -crustal elements, Boundaries
DS1975-0092
1975
Gunn, P.J.Gunn, P.J.Linear Transformation of Gravity and Magnetic FieldsGeophysical Prospecting, Vol. 23, P. 300. (abstract.).KansasGeophysics, Mid-continent
DS1997-0456
1997
Gunn, P.J.Gunn, P.J.Quantitative methods for interpreting aeromagnetic data: a subjectivereviewAgso Journal, Australian Geology And Geophysics, Vol. 17, No. 2, pp. 105-114AustraliaGeophysics - airborne magnetics, Data management - review
DS1997-0457
1997
Gunn, P.J.Gunn, P.J.Regional magnetic and gravity responses of extensional sedimentary basinsAgso Journal, Australian Geology And Geophysics, Vol. 17, No. 2, pp. 115-132AustraliaGeophysics - airborne magnetics, gravity, Basins
DS1997-0458
1997
Gunn, P.J.Gunn, P.J.Application of aeromagnetic surveys to sedimentary basin studiesAgso Journal, Australian Geology And Geophysics, Vol. 17, No. 2, pp. 133-144AustraliaGeophysics - airborne magnetics, gravity, Basins
DS1997-0459
1997
Gunn, P.J.Gunn, P.J., Dentith, M.C.Magnetic responses associated with mineral depositsAgso Journal, Australian Geology And Geophysics, Vol. 17, No. 2, pp. 145-158AustraliaGeophysics - airborne magnetics, Mineral deposits
DS1997-0460
1997
Gunn, P.J.Gunn, P.J., Midment, D., Milligan, P.R.Interpreting aeromagnetic dat a in areas of limited outcropAgso Journal, Australian Geology And Geophysics, Vol. 17, No. 2, pp. 175-186AustraliaGeophysics - airborne, Geological mapping - outcrops
DS1997-0784
1997
Gunn, P.J.Milligan, P.R., Gunn, P.J.Enhancement and presentation of airborne geophysical dataAgso Journal, Australian Geology And Geophysics, Vol. 17, No. 2, pp. 63-76AustraliaGeophysics - airborne, Data management
DS1997-1140
1997
Gunn, P.J.Tarlowksi, C., Gunn, P.J., Mackey, T.Enhancements of the magnetic map of AustraliaAgso Journal, Australian Geology And Geophysics, Vol. 17, No. 2, pp. 77-82AustraliaGeophysics - airborne, Geophysics - magnetics
DS1998-0549
1998
Gunn, P.J.Gunn, P.J., Meixner, A.J.The nature of the basement to the Kimberley block, north-westernAustralia.Australian Society of Exploration Geophysicists (ASEG) International, p. 117. abstractAustraliaGeophysics - aeromagnetics, Kimberley Block
DS200612-0843
2006
Gunn, S.C.Luth, R.W., Gunn, S.C., Ewanchuk, S.M., Stewart, R.J.Formation of natural diamond: an experimental perspective.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 37, abstract only.TechnologyDiamond morphology
DS2001-0428
2001
Gunnell, Y.Gunnell, Y.The interaction between geological structure and global tectonics in multistoreyed Lands cape developments.Geological Society of India Memoir, No. 47, pp.599-644., No. 47, pp.599-644.IndiaSouth Indian Shield - denudation model
DS2001-0429
2001
Gunnell, Y.Gunnell, Y.The interaction between geological structure and global tectonics in multistoreyed Lands cape developments.Geological Society of India Memoir, No. 47, pp.599-644., No. 47, pp.599-644.IndiaSouth Indian Shield - denudation model
DS200812-0157
2008
Gunnell, Y.Burke, K., Gunnell, Y.The African erosion surface: a continental scale synthesis of geomorphology, tectonics and environmental change over the past 180 million years.Geological Society of America Memoir, Memoir 201, gsajournals.orgAfricaBook - geomorphology
DS200812-0158
2008
Gunnell, Y.Burke, K., Gunnell, Y.The African erosion surface: a continental scale synthesis of geomorphology, tectonics and environmental change over the past 180 million years.Geological Society of America, Memoir 201, 72p. $ 45.00AfricaBook - geomorphology
DS1990-0499
1990
Gunnells, G.BFuller, H.K., Gunnells, G.B, Buffa, E.A., Orndorff, R.C.Geologic map index of Virginia, revised and updatedUnited States Geological Survey (USGS), 16p. text 6 sheets -freeGlobalMap, Index of published maps
DS1991-0521
1991
Gunnells, G.B.Fuller, H.K., Gunnells, G.B.GEOINDEX database on geologic maps accessible using GSSEARCH search and retrieval softwareUnited States Geological Survey (USGS) Open file, No. 91-0575 A, B, $ 3.25 and $ 84.00GlobalComputer, Program - GEOINDEX
DS200412-0745
2004
Gunning, M.H.Gunning, M.H.Diamonds challenge uranium for bulk of exploration spending.PDAC Exploration and Developments Highlights, pp. 18-19.Canada, SaskatchewanBrief overview - diamond mentioned
DS1910-0350
1913
Gunsaulus, E.N.Gunsaulus, E.N.South African Mining ProgressU.s. Daily Cons. Trade Repts., No. 243, Oct. 17TH. PP. 310-311.South AfricaMining, Current Activities
DS202009-1673
2020
Gunter, C.Volante, S., Pouteau, A., Collins, W.J., Blereau, E., Li, Z-X., Smit, M., Evans, N.J., Nordsvan, A.R., Spencer, C.J., McDonald, B.J., Li, J., Gunter, C.Multiple P-T-d-t paths reveal the evolution of the final Nuna assembly in northeast Australia. Georgetown InlierJournal of Metamorphic Geology, Vol. 38, pp. 593-627.Australiageochronology

Abstract: The final assembly of the Mesoproterozoic supercontinent Nuna was marked by the collision of Laurentia and Australia at 1.60 Ga, which is recorded in the Georgetown Inlier of NE Australia. Here, we decipher the metamorphic evolution of this final Nuna collisional event using petrostructural analysis, major and trace element compositions of key minerals, thermodynamic modelling, and multi?method geochronology. The Georgetown Inlier is characterised by deformed and metamorphosed 1.70-1.62 Ga sedimentary and mafic rocks, which were intruded by c. 1.56 Ga old S?type granites. Garnet Lu-Hf and monazite U-Pb isotopic analyses distinguish two major metamorphic events (M1 at c. 1.60 Ga and M2 at c. 1.55 Ga), which allows at least two composite fabrics to be identified at the regional scale—c. 1.60 Ga S1 (consisting in fabrics S1a and S1b) and c. 1.55 Ga S2 (including fabrics S2a and S2b). Also, three tectono?metamorphic domains are distinguished: (a) the western domain, with S1 defined by low?P (LP) greenschist facies assemblages; (b) the central domain, where S1 fabric is preserved as medium?P (MP) amphibolite facies relicts, and locally as inclusion trails in garnet wrapped by the regionally dominant low?P amphibolite facies S2 fabric; and (c) the eastern domain dominated by upper amphibolite to granulite facies S2 foliation. In the central domain, 1.60 Ga MP-medium?T (MT) metamorphism (M1) developed within the staurolite-garnet stability field, with conditions ranging from 530-550°C at 6-7 kbar (garnet cores) to 620-650°C at 8-9 kbar (garnet rims), and it is associated with S1 fabric. The onset of 1.55 Ga LP-high?T (HT) metamorphism (M2) is marked by replacement of staurolite by andalusite (M2a/D2a), which was subsequently pseudomorphed by sillimanite (M2b/D2b) where granite and migmatite are abundant. P-T conditions ranged from 600 to 680°C and 4-6 kbar for the M2b sillimanite stage. 1.60 Ga garnet relicts within the S2 foliation highlight the progressive obliteration of the S1 fabric by regional S2 in the central zone during peak M2 metamorphism. In the eastern migmatitic complex, partial melting of paragneiss and amphibolite occurred syn? to post? S2, at 730-770°C and 6-8 kbar, and at 750-790°C and 6 kbar, respectively. The pressure-temperature-deformation-time paths reconstructed for the Georgetown Inlier suggest a c. 1.60 Ga M1/D1 event recorded under greenschist facies conditions in the western domain and under medium?P and medium?T conditions in the central domain. This event was followed by the regional 1.56-1.54 Ga low?P and high?T phase (M2/D2), extensively recorded in the central and eastern domains. Decompression between these two metamorphic events is ascribed to an episode of exhumation. The two?stage evolution supports the previous hypothesis that the Georgetown Inlier preserves continental collisional and subsequent thermal perturbation associated with granite emplacement.
DS201712-2711
2016
Gunter, M.Nestola, F., Burnham, A.D., Peruzzo, L., Tauro, L., Alvaro, M., Walter, M.J., Gunter, M., Anzolini, C., Kohn, S.C.Tetragonal almandine-pyrope phase, TAPP: finally a name for it, the new name jeffbenite.Mineralogical Magazine, Vol. 80, pp. 1219-1232.Technologypyrope

Abstract: Jeffbenite, ideally Mg3Al2Si3O8, previously known as tetragonal-almandine-pyrope-phase (‘TAPP’), has been characterized as a new mineral from an inclusion in an alluvial diamond from São Luiz river, Juina district of Mato Grosso, Brazil. Its density is 3.576 g/cm3 and its microhardness is ?7. Jeffbenite is uniaxial (-) with refractive indexes ??=?1.733(5) and ??=?1.721(5). The crystals are in general transparent emerald green. Its approximate chemical formula is (Mg2.62Fe2+0.27)(Al1.86Cr0.16)(Si2.82Al0.18)O12 with very minor amounts of Mn, Na and Ca. Laser ablation ICP-MS showed that jeffbenite has a very low concentration of trace elements. Jeffbenite is tetragonal with space group I4¯2d, cell edges being a?=?6.5231(1) and c?=?18.1756(3) Å. The main diffraction lines of the powder diagram are [d (in Å), intensity, hkl]: 2.647, 100, 2 0 4; 1.625, 44, 3 2 5; 2.881, 24, 2 1 1; 2.220, 19, 2 0 6; 1.390, 13, 4 2 4; 3.069, 11, 2 0 2; 2.056, 11, 2 2 4; 1.372, 11, 2 0 12. The structural formula of jeffbenite can be written as (M1)(M2)2(M3)2(T1)(T2)2O12 with M1 dominated by Mg, M2 dominated by Al, M3 dominated again by Mg and both T1 and T2 almost fully occupied by Si. The two tetrahedra do not share any oxygen with each other (i.e. jeffbenite is classified as an orthosilicate). Jeffbenite was approved as a new mineral by the IMA Commission on New Minerals and Mineral Names with the code IMA 2014-097. Its name is after Jeffrey W. Harris and Ben Harte, two world-leading scientists in diamond research. The petrological importance of jeffbenite is related to its very deep origin, which may allow its use as a pressure marker for detecting super-deep diamonds. Previous experimental work carried out on a Ti-rich jeffbenite establishes that it can be formed at 13 GPa and 1700 K as maximum P-T conditions.
DS1991-0626
1991
Gunter, M.E.Gunter, M.E., Downs, R.T.Drill: a computer program to aid in building ball and spoke crystalmodelsAmerican Mineralogist, Vol. 76, No. 1-2, Jan-February pp. 293-295GlobalComputer program, Drill: crystal modeling
DS1975-0591
1977
Gunter, W.D.Ogden, P.R.JR., Gunter, W.D., Fandry, C.B.A New Occurrence of Madupite: Leucite Hills, WyomingGeological Society of America (GSA), Vol. 9, No. 6, P. 754, (abstract.).GlobalLeucite Hills, Leucite, Rocky Mountains
DS1975-0829
1978
Gunter, W.D.Ogden, P.R.JR., Sperr, J.T., Gunter, W.D.Morphology of a Recent Ultrapotassic Volcanic Field, Leucite Hills, Southwestern Wyoming.Geological Society of America (GSA), Vol. 10, No. 3, P. 140, (abstract.).GlobalRocky Mountains, Leucite Hills, Leucite
DS1983-0267
1983
Gunter, W.D.Gunter, W.D., Pajari, G.E., Hoinkes, G., Trembath, L.T.Mineral Flow Layering in the Leucite Hills VolcanicsGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC)/CGU, Vol. 8, ABSTRACT VOLUME, P. A32. ( abstract.)United States, Wyoming, Rocky MountainsLeucite, Wyomingite, Orendite
DS1990-0612
1990
Gunter, W.D.Gunter, W.D., Hoinkes, G., Ogden, P., Pajari, G.E.Origin of leucite rich and sanidine roch flow layers in the Leucite Hills volcanic field, WyomingJournal of Geophysical Research, Vol. 95, No. B 10, September 10, pp. 15, 911-15, 928WyomingLeucite, Lamproite -orendite
DS2003-0561
2003
Gunthe, A.Haschke, M., Gunthe, A.Balancing crustal thickening in arcs by tectonic vs magmatic meansGeology, Vol. 31, 11, pp. 933-36.MantleTectonics
DS200412-0803
2003
Gunthe, A.Haschke, M., Gunthe, A.Balancing crustal thickening in arcs by tectonic vs magmatic means.Geology, Vol. 31, 11, pp. 933-36.MantleTectonics
DS1999-0253
1999
Gunther, D.Glasser, S.M., Foley, S.F., Gunther, D.Trace element compositions of minerals in garnet and spinel peridotite xenoliths from the Vitim volcanicsLithos, Vol. 48, No. 1-4, Sept. pp. 263-86.Russia, Siberia, BaikalXenoliths, Volcanic field
DS2000-0518
2000
Gunther, D.Konzett, J., Armstrong, R.A., Gunther, D.Modal metasomatism in the Kaapvaal Craton lithosphere: constraints on timing and genesis of uranium-lead (U-Pb) zircon....Contributions to Mineralogy and Petrology, Vol. 139, No. 6, pp. 704-19.South AfricaXenoliths, metasomatized peridotites, MARID.
DS2000-0779
2000
Gunther, D.Prince, C.I., Kosler, J., Vance, D., Gunther, D.Comparison of laser ablation ICP MS and isotope dilution rare earth elements (REE) analyses - Smneodymium garnet geochronology.Chemical Geology, Vol. 168, No. 3-4, Aug. 1, pp. 255-74.GlobalGarnet chronology - crystal, Age determination, dating, light rare earth element (LREE) enriched minerals
DS2001-0475
2001
Gunther, D.Hermann, J., Muntener, O., Gunther, D.Differentiation of mafic magma in a continental crust to mantle transitionzone.Journal of Petrology, Vol. 42, No. 1, Jan. pp. 189-206.MantleMagmatism
DS2001-1124
2001
Gunther, D.Stalder, R., Ulmer, P., Gunther, D.high pressure fluids in the system MgO SiO2H2 under upper mantle conditionsContributions to Mineralogy and Petrology, Vol. 140, No. 5, pp. 607-18.MantlePressure
DS201112-1009
2011
Gunther, D.Stracke, A., Snow, J.E., Hellebrand, E., Von der Handt, A., Bourdon, B., Birbaum, K., Gunther, D.Abyssal peridotite Hf isotopes identify extreme mantle depletion.Earth and Planetary Science Letters, Vol. 308, 3-4, pp. 359-368.Mantle, Europe, GreenlandGeochronology
DS201212-0447
2012
Gunther, D.Martin, L.H.J., Schmidt, M.W., Mattsson, H.B., Ulmer, P., Hametner, K., Gunther, D.Element partitioning between immiscible carbonatite-kamafugite melts with application to the Italian ultrapotassic suite.Chemical Geology, Vol. 320-321 pp. 96-112.Europe, ItalyCarbonatite
DS1993-0592
1993
Gunther, M.Gunther, M.Heterogeneities of the water content in the earth's mantleAmerican Geophysical Union, EOS, supplement Abstract Volume, October, Vol. 74, No. 43, October 26, abstract p. 682.MantleExperimental petrology, Water
DS1994-0674
1994
Gunther, M.Gunther, M., Jagoutz, E.Isotopic disequilibration temperatures (Samarium/neodymium, Rubidium-Strontium) between mineral phases of coarse grained, low temperature garnet peridotites from Kimberley Floors.Proceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 354-365.South AfricaPeridotites, Deposit -Kimberley Floors
DS1995-0700
1995
Gunther, M.Gunther, M., Jagoutz, E.Age informations in kimberlite derived low temperature garnet lherzolite xenoliths -what do they mean?Terra Nova, Abstract Vol., p. 334.South AfricaXenoliths, Kimberlite
DS1995-0701
1995
Gunther, M.Gunther, M., Jagoutz, E.Ages and processes as reported by isotopes of kimberlite derived low temperature lherzolites.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 205-7.South Africa, Russia, SiberiaGeochronology, Deposit -Kimberley Floors, Jagersfontein, Udachnaya, Mir
DS2000-0717
2000
Gunther, M.Ntaflos, Th., Gunther, M., Labudia, H.C., Bjerg, E.A.Isotopic and geochemical evolution of the Cenozoic basalts from Rio Negro Patagonia Argentina.Igc 30th. Brasil, Aug. abstract only 4p.ArgentinaGeochronology, Basanites
DS1975-1041
1979
Gunthorpe, R.J.Gunthorpe, R.J., Buerger, A.D.The Otjisazu Igneous Complex a Recently Identified Carbonatite Locality in Central Southwest Africa.Geo. Soc. Sth. Afr. 18th. Congr., Vol. 78, PT. 1, PP. 161-163.Southwest Africa, NamibiaCarbonatite, Related Rocks
DS1986-0317
1986
GuoGuo, Jiugao, Cai Xiucheng, Deng Huaxing, Chen Feng, Tan Yi MeiNatural type 1B diamonds in diamond placer in Hunan province. *CHIKexue Tongbao, *CHI, Vol. 31, No. 4, pp. 257-261ChinaDiamond morphology
DS1986-0318
1986
GuoGuo, Jiugao, Chen Feng, et al.Color of placer diamonds in Hunan province.*CHIKuangwu Xuebao, *CHI, Vol. 6, No.2, pp. 132-138ChinaPlacer, Diamond
DS1990-0921
1990
GuoLeung, I.S. , Guo, WX, Friedman, I., Gleason, J.Natural occurrence of silicon-carbide in a Diamondiferous kimberlite fromFuxianNature, Vol. 346, No. 6282, July 26, pp. 352-354ChinaDiamond genesis -Silicon carbide, Mineralogy -kimberlite
DS200712-0826
2007
GuoPeng, P., Zhai, M-G., Guo, J-H, Kusky, T.,Ping, T.Nature of mantle source contributions and crystal differentiation in the petrogenesis of the 1.78 Ga mafic dykes in the central North Chin a Craton.Gondwana Research, Vol. 12, 1-2, August pp. 29-46.ChinaDyke chemistry
DS200712-0827
2007
GuoPeng, P., Zhai, M-G., Guo, J-H, Kusky, T.,Ping, T.Nature of mantle source contributions and crystal differentiation in the petrogenesis of the 1.78 Ga mafic dykes in the central North Chin a Craton.Gondwana Research, Vol. 12, 1-2, August pp. 29-46.ChinaDyke chemistry
DS201809-2016
2018
GuoDuan, Yunfei, Sun, Ningyu, Wang, Siheng, Li, Xinyang, Guo, Xuan, Ni.Phase stability and thermal equation of state of delta -AIOOH: implication for water transportation in the deep lower mantle.Earth and Planetary Science Letters, Vol. 494, 1, pp. 92-98.Mantlewater

Abstract: In this study, we present new experimental constraints on the phase stability and thermal equation of state of an important hydrous phase, ?-AlOOH, using synchrotron X-ray diffraction up to 142 GPa and 2500 K. Our experimental results have shown that ?-AlOOH remains stable at the whole mantle pressure-temperature conditions above the D? layer yet will decompose at the core-mantle boundary because of a dramatic increase in temperature from the silicate mantle to the metallic outer core. At the bottom transition zone and top lower mantle, the formation of ?-AlOOH by the decomposition of phase Egg is associated with a ?2.1-2.5% increase in density (?) and a ?19.7-20.4% increase in bulk sound velocity (V?). The increase in ? across the phase Egg to ?-AlOOH phase transition can facilitate the subduction of ?-AlOOH to the lower mantle. Compared to major lower-mantle phases, ?-AlOOH has the lowest ? but greatest V?, leading to an anomalous low ? /V? ratio which can help to identify the potential presence of ?-AlOOH in the region. More importantly, water released from the breakdown of ?-AlOOH at the core-mantle boundary could lower the solidus of the pyrolitic mantle to cause partial melting and/or react with Fe in the region to form the low-velocity FeO2Hx phase. The presence of partial melting and/or the accumulation of FeO2Hx phase at the CMB could be the cause for the ultra-low velocity zone. ?-AlOOH is thus an important phase to transport water to the lowermost mantle and helps to understand the origin of the ultra-low velocity zone.
DS2001-0254
2001
Guo, A.Dickin, A.P., Guo, A.The location of the Allochthon boundary thrust and the Archean Proterozoic suture in the Mattawa area.Precambrian Research, Vol. 107, No. 1-2, Mar. 30, pp. 31-44.OntarioGeochronology - neodymium isotope evidence, Grenville Province
DS202110-1624
2021
Guo, B-J.Long, Z-Y., Yu, X-Y., Jiang, X., Guo, B-J., Ma, C-Y., You, Y., Zheng, Y-Y.Fluid boiling and fluid-rock interaction as primary triggers for emerald deposition: insights from the Dayakou emerald deposit ( China).Ore Geology Reviews, Vol. 139, 104454, 15p. PdfChinaemerald

Abstract: The formation of tectonic magmatic-related emerald deposits necessarily invokes a mixing model of Be-rich granitic rocks and Cr and/or V-rich surrounding rocks. However, there has been continuing debate on the deposit genesis, with the essential controversy being the relative significance of magma versus metamorphism in mineralizing as well as the key triggers for emerald deposition. The Dayakou emerald deposit genetically related to the Cretaceous granitic magmatism and hosted within the Neoproterozoic metasedimentary rocks is an ideal study case to probe into the above outstanding issue. In this paper, three hydrothermal mineralization and related alteration stages have been recognized in Dayakou, comprised of the greisenization and early emerald mineralization in high-temperature hydrothermal condition (stage-I; peak at 380 °C to 480 °C), the silicification and main emerald mineralization in medium-high temperature fluid (stage-II; peak at 300 °C to 360 °C) and the late carbonate alteration and scheelite mineralization (stage-III). Analysis results of fluid inclusion and C-H-O isotopes of emeralds and associated minerals suggest that ore-forming fluids belong to the H2O-NaCl ± CO2 system with minor H2S, CH4, and N2, exsolved from the Cretaceous granites and gradually interacted with the surrounding metamorphic rocks. We combine the new data with those reported in earlier studies to further propose a genesis scenario for the Dayakou deposit, in which Be-bearing fluids originally exsolved from peraluminous melts and fluoride complexes may be an effective transport proxy for Be in hydrothermal fluids. Fluid boiling during fluid ascent leads to the significant fractionation and enrichment of elements and the escape of volatiles (e.g., HF, H2O, CO2) in ore system. Meanwhile, sustained fluid-rock interaction (e.g., greisenization) increasingly extracts Cr, V and Ca into fluids to facilitate mineral precipitation, wherein the crystallization of fluoride minerals would cause the destabilization of Be-F complexes. Our study indicates that fluid boiling and fluid-rock interactions are the primary triggers for emerald deposition.
DS1995-0043
1995
Guo, D.Anderson, O.L., Masuda, K., Guo, D.Pure silicate perovskite and the PREM lower mantle model: a thermodynamicanalysis.Physics of the Earth and Plan. Interiors, Vol. 89, pp. 35-49.MantlePerovskite
DS201904-0742
2019
Guo, D.Guo, D., Liu, Y.Occurrence and geochemistry of bastnasite in carbonatite related REE deposits, Mianning Dechang REE belt, Sichuan Province SW China.Ore Geology Reviews, Vol. 107, pp. 266-282.Chinacarbonatite

Abstract: Bastnäsite is the main ore mineral in many carbonatite-related rare earth element (REE) deposits, which account for ?51% of rare-earth oxide reserves worldwide. However, the occurrence, geochemistry, and genetic significance of bastnäsite has not been methodically investigated. The Cenozoic Mianning-Dechang (MD) REE belt in Sichuan Province, SW China, contains the Maoniuping, Dalucao, Lizhuang, and Muluozhai deposits as well as numerous smaller REE occurrences. Individual deposits within the belt contain different types of bastnäsite-bearing ore, which provides a unique opportunity to explore in detail the common mechanisms controlling the formation of bastnäsite-rich REE deposits. Here, we present detailed results from field observations and petrographic, geochemical, and fluid inclusion studies of bastnäsite from the main MD deposits. Calcite, fluorite, and barite form stable mineral assemblages that are commonly overprinted by bastnäsite. Homogenization temperatures of fluid inclusions in bastnäsite of ?150-270?°C (Dalucao and Lizhuang deposits) and 155-210?°C (Maoniuping deposit) are systematically lower than those of fluid inclusions in gangue minerals. Therefore, the petrographic studies and homogenization temperatures both show that large-scale crystallization of bastnäsite took place during the later stage of the hydrothermal system. The bastnäsite, relatively geochemically homogeneous within all of the MD deposits, is enriched in Ba (293-8425?ppm), Th (16.4-2527?ppm), and U (4.19-92.7?ppm), and relatively depleted in high field strength elements such as Nb (0.15-17.4?ppm), Ta (0.06-6.48?ppm), Zr (0.71-31.1?ppm), Hf (0.62-5.65?ppm), and Ti (<60?ppm), the same to carbonatite, and ore veins. In comparison, the samples from the study area show an increase in average REE contents from syenites to carbonatites to ore veins (i.e., bastnäsite-bearing ores) and finally to bastnäsite. Lanthanum and Ce were commonly substituted by Th, U, Sc, Ba, and Sr supplied by more evolved hydrothermal fluids. Combining the present results with existing data, we present a three-stage model for the formation of carbonatite-related REE deposits. First, partial melting of metasomatized sub-continental lithospheric mantle, fluxed by REE- and CO2-rich fluids, forms the parental carbonatite-syenite magma. Second, Sr, Ba, and REEs are strongly partitioned into carbonatite melts during liquid immiscibility in the carbonatite-syenite magmatic system. Third, hydrothermal fluids exsolved from the crystalizing syenite and carbonatite magmas form ore veins with early gangue minerals and later bastnäsite overgrowths. Consequently, barite, calcite, and fluorite assemblages are a valuable guide in REE exploration.
DS2001-0430
2001
Guo, F.Guo, F., Fan, W.M., Wang, Y.J., Lin, G.Late Mesozoic mafic intrusive complexes in North Chin a Block; constraints on the nature of subcontinental..Physics and Chemistry of the Earth Pt. A. Solid Earth, Vol. 26, No. 9-10, pp. 759-71.ChinaLithospheric mantle, Magmatism
DS2003-0521
2003
Guo, F.Guo, F., Fan, W., Wang, F., Lin, G.Geochemistry of late Mesozoic mafic magmatism in west Shandong Province, easternGeochemical Journal, Vol. 37, pp. 63-77.ChinaBlank
DS200412-0534
2004
Guo, F.Fan, W-M., Guo, F., Wang, Y-J, Zhang, M.Late Mesozoic volcanism in the northern Huaiyang tectono-magmatic belt: partial melts from lithospheric mantle with subducted coChemical Geology, Vol. 209, 1-2, pp. 27-48.ChinaUHP, Dabie Orogen, subduction
DS200412-0746
2003
Guo, F.Guo, F., Fan, W., Wang, F., Lin, G.Geochemistry of late Mesozoic mafic magmatism in west Shandong Province, eastern China: characterizing the lost lithospheric manGeochemical Journal, Vol. 37, pp. 63-77.ChinaUHP, xenoliths
DS200412-0747
2004
Guo, F.Guo, F., Fan, W., Wang, Y., Li, C.When did the Emeishan mantle plume activity start? Geochronological and geochemical evidence from ultramafic mafic dykes in soutInternational Geology Review, Vol. 46, 3, pp. 226-234.ChinaPlume, geochronology
DS200412-0748
2004
Guo, F.Guo, F., Fan, W., Wang, Y., Zhang, M.Origin of early Cretaceous calc-alkaline lamprophyres from the Sulu Orogen in eastern China: implications for enrichment processLithos, Vol. 78, 3, Nov. pp. 291-305.ChinaGeochemistry, geochronology, mantle metasomatism, subdu
DS200612-0512
2006
Guo, F.Guo, F., Fan, W., Li, C.Geochemistry of late Mesozoic adakites from the Sulu belt, China: magma genesis and implications for crustal recycling beneath continental collisional orogens.Geological Magazine, Vol. 143, 1, pp. 1-13.ChinaCrust, Geochemistry REE, eclogite
DS200612-0818
2005
Guo, F.Lin, G., Zhang, Y., Guo, F., Wang, Y., Fan, W.Numerical modeling of lithosphere evolution in the North Chin a craton; thermal versus tectonic thinning.Journal of Geodynamics, Vol. 40, 1, pp. 92-103.ChinaTectonics
DS201112-0590
2011
Guo, F.Li, C., Guo, F., Fan, W.Lower crustal melting via magma underplating: elemental Sr Nd Pb isotopic constraints from late Mesozoic intermediate felsic volcanic rocks in NE Chin a block.Island Arc, in press available,ChinaGeochemistry, alkaline - shoshonites
DS201906-1266
2019
Guo, F.Alemayehu, M., Guo, F., Aulbach, S.Transformation of continental lithospheric mantle beneath the East African Rift: constraints from platinum group elements and Re-Os isotopes in mantle xenoliths from Ethiopia.Contributions to Mineralogy and Petrology, Vol. 174, 5, 27p.Africa, Ethiopiaxenoliths

Abstract: The behavior of sub-continental lithospheric mantle (SCLM) in extensional settings, up to successful rifting, plays an important role in geodynamics and in the global carbon cycle, yet the underlying processes and rates of lithosphere destruction remain poorly constrained. We determined platinum-group element (PGE: Os, Ir, Ru, Pt, and Pd) abundances and Re-Os-isotope systematics for well-characterized mantle xenoliths hosted in Cenozoic basalts from the northwestern plateau (Gundeweyn area) and southern rift zone (Dillo and Megado areas) of Ethiopia to provide new insights on the nature and timing of processes leading to the formation and transformation of the off-cratonic lithospheric mantle beneath the East Africa rift system (EARS). The whole-rock PGE concentrations are highly variable, with total PGE abundances ranging from 6.6 to 12.6 ppb for Gundeweyn, 11.5 to 23.3 ppb for Dillo, and 9.9 to 19.4 ppb for Megado mantle xenoliths. The 187Os/188Os ratios of the whole-rock mantle xenoliths vary from 0.1180 to 0.1287 for Gundeweyn, 0.1238 to 0.1410 for Dillo and 0.1165 to 0.1277 for Megado, compared to 0.130 for the Afar plume and???0.14 for the Kenya plume, with Re depletion ages up to 1.45 Ga for Gundeweyn, 0.64 Ga for Dillo, and 1.65 Ga for Megado mantle xenoliths. The regional differences between refertilizing agents recorded in mantle xenoliths from the plateau area and the rift systems reflect distinct tectonomagmatic settings: (1) low PGE abundances, with some retention of low 187Os/188Os in Gundeweyn peridotites, are ascribed to scavenging by early small-volume oxidizing melts, generated in the convecting mantle ahead of the arrival of the Afar plume. (2) Percolation of late-stage silicate/basaltic melts, associated with the arrival of hot mantle plume and lithosphere thinning in the rift setting, locally led to refertilization and sulfide precipitation and partial replenishment of the PGE (Dillo), with convecting mantle-like 187Os/188Os. Local enclaves of older, cryptically metasomatised mantle with unradiogenic Os (Megado) attest to the heterogeneous nature of melt-peridotite interaction at this stage (pervasive vs. focused melt flow). Highly depleted abundances of the compatible PGE are characteristic of SCLM affected by incipient rifting and percolation of oxidizing melts, here associated with the Afar and Kenya plume beneath the East Africa rift, and may be precursors to advanced degrees of lithosphere destruction/transformation.
DS201907-1586
2019
Guo, G.Xu, X., Cartigny, P., Yang, J., Dilek, Y., Xiong, F., Guo, G.FTIR spectroscopy data and carbon isotope characteristics of the ophiolite hosted diamonds.Acta Geologica Sinica, Vol. 93, 1, p.38.Asia, Russiamicrodiamonds

Abstract: We report new ?13C ?values data and N?content and N?aggregation state values for microdiamonds recovered from peridotites and chromitites of the Luobusa ophiolite (Tibet) and chromitites of the Ray?Iz ophiolite in the Polar Urals (Russia). All analyzed microdiamonds contain significant nitrogen contents (from 108 up to 589 ± 20% atomic ppm) with a consistently low aggregation state, show identical IR spectra dominated by strong absorption between 1130 cm?1 and 1344 cm?1, and hence characterize Type Ib diamond. Microdiamonds from the Luobusa peridotites have ?13C ?PDB?values ranging from ?28.7‰ to ?16.9‰, and N?contents from 151 to 589 atomic ppm. The ?13C and N?content values for diamonds from the Luobusa chromitites are ?29‰ to ?15.5‰ and 152 to 428 atomic ppm, respectively. Microdiamonds from the Ray?Iz chromitites show values varying from ?27.6 ‰ to ?21.6 ‰ in ?13C and from 108 to 499 atomic ppm in N. The carbon isotopes values bear similar features with previously analyzed metamorphic diamonds from other worldwide localities, but the samples are characterized by lower N?contents. In every respect, they are different from diamonds occurring in kimberlites and impact craters. Our samples also differ from the few synthetic diamonds; we also analyzed showing enhanced ?13C ?variability and less advanced aggregation state than synthetic diamonds. Our newly obtained N?aggregation state and N?content data are consistent with diamond formation over a narrow and rather cold temperature range (i.e. <950°C), and in a short residence time (i.e. within several million years) at high temperatures in the deep mantle.
DS202103-0385
2020
Guo, H.Guo, H., Yu, X., Zheng, Y., Sun, Z., Ng, M.F-Y.Inclusion and trace element characteristics of emeralds from Swat Valley, Pakistan.Gems & Gemology, Vol. 56, 3, pp. 336-355. pdfAsia, Pakistandeposit - Swat Valley. Emerald

Abstract: Swat Valley has become an important source of emeralds, including recently discovered trapiche-type crystals. In this study, emerald samples from Swat were examined by standard gemological testing, UV-Vis-NIR, FTIR, Raman analysis, EDXRF, and LA-ICP-MS. The study found three-phase hexagonal inclusions consisting of water, gaseous carbon dioxide and nitrogen, and a magnesite crystal. The gaseous mixture in two-phase inclusions is characteristic in both trapiche-type (CO2 + N2) and non-trapiche samples (CO2 + N2 + CH4). Mineral inclusions of hematite, magnetite, rutile, graphite, and siderite are reported for the first time. Regular non-trapiche-type Swat emeralds contain high chromium (avg. 7471 ppmw), alkali metal (avg. 21040 ppmw), magnesium (avg. 34263 ppmw), and iron (avg. 9265 ppmw), as well as scandium (avg. 633 ppmw). Infrared spectra show that the absorption of type II H2O is stronger than that of type I H2O. Logarithm plots of trace elements appear to be diagnostic. Based on Raman spectroscopy, the trapiche-type emeralds’ colorless core, light green hexagonal growth zone area, and green rim are emerald, while the six black arms are a mixture of hematite and graphite.
DS1994-0676
1994
Guo, J.Guo, J., O'Reilly, S.Y., Griffin, W.L.Mid-crustal carbonatites: evidence from inclusions in corundum megacrystsGeological Association of Canada (GAC) Abstract Volume, Vol. 19, p.MantleCarbonatite
DS1996-0574
1996
Guo, J.Guo, J., O'Reilly, S.Y., Griffin, W.L.Zircon inclusions in corundum megacrysts: 1. trace element geochemistry and clues to the origin ...Geochimica et Cosmochimica Acta, Vol. 60, No. 13, pp. 2347-63.Australia, ChinaGeochemistry - corundum megacrysts, Alkali basalts
DS1999-0276
1999
Guo, J.Guo, J., Griffin, W.L., O'Reilly, S.Y.Geochemistry and origin of sulphide minerals in mantle xenoliths, Qilin, southeastern China.Journal of Petrology, Vol. 40, No. 7, July pp. 1125-50.China, southeastXenoliths, Geochemistry
DS2002-1720
2002
Guo, J.Windley, B.F., Kroner, A., Guo, J., Qu, G., Li, Y., Zhang, C.Neoproterozoic to Paleozoic geology of the Altai Orogen NW China: new zircon age dat a and tectonic evolution.Journal of Geology, Vol. 110, 6, pp. 719-738.ChinaGeochronology
DS2003-0245
2003
Guo, J.Chen, F., Siebel, W., Guo, J., Cong, B., Satir, M.Late Proterozoic magmatism and metamorphism in gneisses from the Dabie highPrecambrian Research, Vol. 120, 1-2, pp.131-148.ChinaMagmatism, UHP
DS2003-1542
2003
Guo, J.Zhai, M., Guo, J., Li, Y., Peng, P., Shi, X.Two linear granite belts in the central western North Chin a Craton and their implicationPrecambrian Research, Vol. 127, 1-2, Nov. pp.267-283.ChinaTectonics
DS200412-0316
2003
Guo, J.Chen, F., Siebel, W., Guo, J., Cong, B.,Satir, M.Late Proterozoic magmatism and metamorphism in gneisses from the Dabie high pressure metamorphic zone, eastern China: evidence fPrecambrian Research, Vol. 120, 1-2, pp.131-148.ChinaMagmatism UHP
DS200412-2200
2003
Guo, J.Zhai, M., Guo, J., Li, Y., Peng, P., Shi, X.Two linear granite belts in the central western North Chin a Craton and their implication for Late Neoarchean Paleoproterozoic coPrecambrian Research, Vol. 127, 1-2, Nov. pp.267-283.ChinaTectonics
DS200512-0836
2005
Guo, J.Peng, P., Zhai, M., Zhang, H., Guo, J.Geochronological constraints on the Paleoproterozoic evolution of the North Chin a Craton: SHRIMP zircon ages of different types of mafic dikes.International Geology Review, Vol. 47, 5, May, pp. 492-508.ChinaGeochronology
DS200512-1236
2005
Guo, J.Zhai, M., Guo, J., Liu, W.Neoarchean to Paleoproterozoic continental evolution and tectonic history of the North Chin a Craton: a review.Journal of Asian Earth Sciences, Vol. 24, 5, pp. 547-561.ChinaTectonics
DS200812-0879
2008
Guo, J.Peng, P., Zhai, M., Ernst, R.E., Guo, J., Liu, F., Hu, B.A 1.78 Ga large igneous province in the North Chin a Craton: the Xionger volcanic province and the North Chin a dyke swarm.Lithos, Vol. 101, 3-4, pp. 260-280.ChinaGeochemistry
DS200812-1237
2008
Guo, J.Wang, Q., Shi, Y., Lin Wei, Guo, J.Exhumation of the Dabie UHP terrane, China.International Geology Review, Vol. 50, 1, pp. 15-31.ChinaUHP
DS201312-0441
2013
Guo, J.Jiang, N., Guo, J., Chang, G.Nature and evolution of the lower crust in the eastern North Chin a craton: a review.Earth Science Reviews, in press availableChinaCraton
DS1990-0615
1990
Guo, J.F.Guo, J.F., Green, T.H.Experimental study of barium partitioning between phlogopite and silicate liquid at upper-mantle pressure and temperatureLithos, Vol. 24, No. 2, March pp. 83-95GlobalExperimental petrology, Mantle
DS1990-0616
1990
Guo, J.F.Guo, J.F., Green, T.H., O'Reilly, S.Y.Barium partitioning and anorthoclase megacryst genesisGeological Society of Australia Abstracts, No. 25, No. A12.11 pp. 239. AbstractAustraliaMagma, barium, Ba content
DS1988-0101
1988
Guo, J.G.Cai Xiucheng, Guo, J.G., Chen, F., Tang, R.B.EPR study of atom pairs of impurity nitrogen in natural diamond. *CHIKexue Tong, *CHI, Vol. 33, No. 22, November pp. 1886-1889GlobalNatural diamond, Diamond inclusions-nitrog
DS1993-0241
1993
Guo, J.G.Chen, F., Guo, J.G., Wang, S.X., Wang, M.Z., et al.Discovery of salt inclusions in diamond.*CHIChinese Science Bulletin, *CHI, Vol. 38, No. 2, January pp. 147-150ChinaDiamond inclusions, Salt
DS2001-1298
2001
Guo, J.H.Zhai, M.G., Guo, J.H., Liu, W.J.An exposed cross section of early Precambrian continental lower crust in North Chin a Craton.Physics and Chemistry of the Earth, Vol. 26, pt. A. No. 9-10, pp. 781-92.ChinaMantle, Geology
DS2001-1299
2001
Guo, J.H.Zhai, M.G., Guo, J.H., Liu, W.J.An exposed cross section of early Precambrian continental lower crust in North Chin a craton.Physics and Chemistry of the Earth Pt. A. Solid Earth, Vol. 26, No. 9-10, pp. 781-92.ChinaTectonics
DS200612-0838
2006
Guo, J.H.Lu, X.P., Wu, F.Y., Guo, J.H., Wilde, S.A., Yang, J.H., Liu, X.M., Zhang, XoZircon U Pb geochronological constraints on the Paleoproterozoic crustal evolution of the Eastern Block in the North Chin a Craton.Precambrian Research, Vol. 146, 3-4, pp. 138-164.ChinaGeochronology
DS201212-0824
2013
Guo, J-H.Zhao, X-M., Zhang, H-F., Su, F., Lo, C-H., Yang, S-H., Guo, J-H.Phlogopite 40 Ar/39 Ar geochronology of mantle xenoliths from the North Chin a craton: constraints on the eruption ages of of Cenozoic basalts.Gondwana Research, Vol. 23, 1, pp. 208-219.ChinaGeochronology
DS201911-2572
2019
Guo, J-h.Wang, D., Romer, R.L., Guo, J-h., Glodny, J.Li and B isotopic fingerprint of Archean subduction.Geochimica et Cosmochimica Acta, in press available. 45p.Mantlesubduction

Abstract: Archean peridotite xenoliths in the ?2.52 Ga Zhulagou diorite (Yinshan Block, North China Craton) show chemical and Li isotopic evidence for metasomatism above an ancient subduction zone. The peridotite xenoliths are composed of olivine + orthopyroxene + amphibole + phlogopite + serpentine. The peridotite xenoliths have low whole-rock Mg# (80-81) and low Mg# (81-84) in olivine, indicating that they are cumulates that formed near the crust-mantle boundary. Petrological observations, mineral trace element data and isotopic ages show that the sequence of hydrous minerals is amphibole-serpentine-phlogopite. SIMS U-Pb dating of zircon from peridotites yielded an upper intercept age at ?2.53 Ga, and a U-Pb lower intercept age at ?1.8 Ga. The age of ?2.53 Ga is interpreted to date the crystallization of zircon from the metasomatized mantle melt that formed the Zhulagou cumulate peridotite. Rb-Sr mineral isochrons date phlogopite formation at ?1760 Ma, consistent with the lower intercept age of zircon. Pargasitic amphibole from the Zhulagou peridotites has fractionated REE, pronounced depletions of Nb, Ta, Zr and Ti, and heavy ?7Li (?+14‰) and light ?11B (?-11‰). Combined with slightly depleted mantle whole rock ?Nd (?+1.3) and high zircon ?18O (+5.6 to +7.0‰), the amphibole composition reflects that the peridotite xenoliths formed from melts that carried the geochemical and isotopic fingerprint typical for a metasomatized mantle wedge above a subduction zone. The Zhulagou peridotite xenoliths have the highest ?7Li values (?+12‰) recorded in Archean peridotites. Isotopically heavy Li and light B in olivine, orthopyroxene, and amphibole from the peridotite xenoliths show that Li and B may decouple during partial melting or fluid release from the subducted slab. The decoupling of Li and B may have a variety of reasons, including different host minerals for Li and B in the source and different protoliths in the subducted slab. The Li and B isotopic record on the recycling of ancient material demonstrates that modern-style subduction operated already in the late Archean.
DS202001-0046
2019
Guo, J-h.Wang, D., Romer, R.L., Guo, J-h., Glodny, J.Li and B isotopic fingerprint of Archean subduction.Geochimica et Cosmochimica Acta, in press available pdf 45p.Chinacraton

Abstract: Archean peridotite xenoliths in the ?2.52?Ga Zhulagou diorite (Yinshan Block, North China Craton) show chemical and Li isotopic evidence for metasomatism above an ancient subduction zone. The peridotite xenoliths are composed of olivine?+?orthopyroxene?+?amphibole?+?phlogopite?+?serpentine. The peridotite xenoliths have low whole-rock Mg# (80-81) and low Mg# (81-84) in olivine, indicating that they are cumulates that formed near the crust-mantle boundary. Petrological observations, mineral trace element data and isotopic ages show that the sequence of hydrous minerals is amphibole-serpentine-phlogopite. SIMS U-Pb dating of zircon from peridotites yielded an upper intercept age at ?2.53?Ga, and a U-Pb lower intercept age at ?1.8?Ga. The age of ?2.53?Ga is interpreted to date the crystallization of zircon from the metasomatized mantle melt that formed the Zhulagou cumulate peridotite. Rb-Sr mineral isochrons date phlogopite formation at ?1760?Ma, consistent with the lower intercept age of zircon. Pargasitic amphibole from the Zhulagou peridotites has fractionated REE, pronounced depletions of Nb, Ta, Zr and Ti, and heavy ?7Li (?+14‰) and light ?11B (?-11‰). Combined with slightly depleted mantle whole rock ?Nd (?+1.3) and high zircon ?18O (+5.6 to +7.0‰), the amphibole composition reflects that the peridotite xenoliths formed from melts that carried the geochemical and isotopic fingerprint typical for a metasomatized mantle wedge above a subduction zone. The Zhulagou peridotite xenoliths have the highest ?7Li values (?+12‰) recorded in Archean peridotites. Isotopically heavy Li and light B in olivine, orthopyroxene, and amphibole from the peridotite xenoliths show that Li and B may decouple during partial melting or fluid release from the subducted slab. The decoupling of Li and B may have a variety of reasons, including different host minerals for Li and B in the source and different protoliths in the subducted slab. The Li and B isotopic record on the recycling of ancient material demonstrates that modern-style subduction operated already in the late Archean.
DS201906-1340
2019
Guo, K.Qiao, X., Zhou, Z., Schwarz, D.T., Qi, L., Gao, J., Nong, P., Lai, M., Guo, K., Li, Y.Study of the differences in infrared spectra of emerald from different mining areas and the controlling factors.The Canadian Mineralogist, Vol. 57, pp. 65-79.Globalemerald genesis

Abstract: Natural emeralds from 11 mining areas were studied using an infrared spectrometer. The results showed different spectroscopic characteristics for emerald from different mine regions. Infrared absorption is mainly attributed to the vibration of Si-O lattice, channel water, alkaline cations, and molecules such as CO2, [Fe2(OH)4]2+, etc. Both near-infrared and mid-infrared spectra showed that the differences in band positions, intensities, and shapes are related to the mixed ratio of the two types of channel water. Accordingly, emerald and its mining regions can be divided into 3 types: H2O I, H2O II, and transition I-II. Furthermore, the study indicates that the relative amounts of the two different orientations of channel water molecules are mainly affected by the presence of (Mg + Fe)2+ in the host rock or in the mineralizing fluid. Therefore, the mineralization environment type (alkali-poor, alkali-rich, and transitional types) of emerald can be preliminarily identified from IR spectroscopy. This can be useful for determining the origin of emeralds.
DS200612-1590
2006
Guo, K-Y.Zhang, C-L., Li, Z.X., Li, X-H., Ye, H., Wang, A., Guo, K-Y.Neoproterozoic bimodal intrusive complex in the southwestern Tarim Block, northwest China: age, geochemistry, and implications for rifting of Rodinia.International Geology Review, Vol. 48, 2, Feb. pp. 112-128.ChinaGeochronology
DS201802-0225
2018
Guo, L.Chen, N., Ma, H., Chen, L., Yan, B., Fang, C., Liu, X., Li, Y., Guo, L., Chen, L., Jia, X.Effects of S on the synthesis of type 1b diamond under high pressure and high temperature.International Journal of Refractory Metals & Hard Materials, Vol. 71, pp. 141-146.Technologysynthetic diamonds
DS1994-1879
1994
Guo, Lh.Wang, A., Dhamelin, P., Meyer, H.O.A., Guo, Lh.A carbon rich multiphase inclusion in a Chinese diamond and its geochemicalimplication.Contributions to Mineralogy and Petrology, Vol. 117, No. 1, June pp. 15-24.ChinaDiamond inclusion, Carbon
DS201312-0011
2013
Guo, M.Ahlqvist, O., Harvey, F., Ban, H., Chen, W., Fonanella, S., Guo, M.,Singh, N.Making journal articles 'live': turning academic writing into scientific dialog.Geojournal, Vol. 78, 1, pp. 61-68.TechnologyKnowledge dissemination
DS201312-0346
2014
Guo, P.Guo, P., Niu, Y., Yu, X.A synthesis and new perspective on the petrogenesis of kamafugites from West Qinling, China, in a global context.Journal of Asian Earth Sciences, Vol. 79, 5, pp. 86-96.ChinaKamafugite
DS201412-0326
2013
Guo, P.Guo, P., Niu, Y., Yu, X.A synthethis and new perspective on the petrogenesis of kamafugites from West Qinling, China, in a global context.Journal of Asian Earth Sciences, Vol. 79, pp. 86-96.ChinaKamafugite
DS202001-0020
2020
Guo, P.Ionov, D.A., Guo, P., Nelson, W.R., Shirey, S.B., Willbold, M.Paleoproterozoic melt depleted lithospheric mantle in the Khanka block, far eastern Russia: inferences for mobile belts bordering the North China and Siberian cratons.Geochimica et Cosmochimica Acta, Vol. 270, pp. 95-111.China, Russiametasomatism, melting

Abstract: The eastern part of Asia between the North China and Siberian cratons contains orogenic belts formed by the Paleo-Asian and Pacific subduction and older continental blocks. A fundamental question regarding these and all mobile belts is the fate of the continental lithospheric mantle (CLM) during their formation, i.e. whether, or to what extent the CLM may be formed, replaced or affected during orogeny. Insights into these processes can be obtained from mantle xenoliths hosted by Cenozoic basalts in the Proterozoic Khanka block in the far eastern Russia between NE China and the Pacific coast of Asia. We report petrographic, chemical, and Os-Sr-Nd isotope data for spinel peridotite xenoliths at two Khanka sites: Sviyagin and Podgelban. The modal abundances and chemical compositions suggest that the peridotites are residues of low to moderate degrees of melt extraction from fertile mantle. They show an 187Os/188Os vs. 187Re/188Os correlation with an apparent 1.9?Ga age; the 187Os/188Os ratios are positively correlated with Al2O3 and other melt extraction indices. These results provide the first robust CLM age constraints for the eastern Central Asian Orogenic Belt (CAOB). The ages suggest that the ancient CLM of the Khanka block may be roughly coeval with reworked CLM at Hannuoba (North China craton), and that it persisted through the Phanerozoic orogenies. Moreover, despite the proximity to Phanerozoic subduction zones, the Khanka CLM shows little post-melting enrichment, e.g. the clinopyroxenes are typically LREE-depleted and have Sr-Nd isotope ratios typical of the MORB mantle. We posit that the metasomatism of the CLM, earlier proposed for North China xenolith suites and ascribed to the effects of Pacific or older subduction and related mantle upwelling, may not be widespread in the CAOB. In general, Proterozoic blocks composed of residual peridotites may be more common in the CLM of the SE Siberia and northern China, and possibly other orogenic belts, than previously thought.
DS202002-0194
2020
Guo, P.Ionov, D.A., Guo, P., Nelson, W.R., Shirey, S.B., Willbold, M.Paleoproterozoic melt depleted lithospheric mantle in the Khanka block, far eastern Russia: inferences for mobile belts bordering the North China and Siberian cratons.Geochimica et Cosmochimica Acta, Vol. 270, pp. 95-111.Russiaperidotites

Abstract: The eastern part of Asia between the North China and Siberian cratons contains orogenic belts formed by the Paleo-Asian and Pacific subduction and older continental blocks. A fundamental question regarding these and all mobile belts is the fate of the continental lithospheric mantle (CLM) during their formation, i.e. whether, or to what extent the CLM may be formed, replaced or affected during orogeny. Insights into these processes can be obtained from mantle xenoliths hosted by Cenozoic basalts in the Proterozoic Khanka block in the far eastern Russia between NE China and the Pacific coast of Asia. We report petrographic, chemical, and Os-Sr-Nd isotope data for spinel peridotite xenoliths at two Khanka sites: Sviyagin and Podgelban. The modal abundances and chemical compositions suggest that the peridotites are residues of low to moderate degrees of melt extraction from fertile mantle. They show an 187Os/188Os vs. 187Re/188Os correlation with an apparent 1.9?Ga age; the 187Os/188Os ratios are positively correlated with Al2O3 and other melt extraction indices. These results provide the first robust CLM age constraints for the eastern Central Asian Orogenic Belt (CAOB). The ages suggest that the ancient CLM of the Khanka block may be roughly coeval with reworked CLM at Hannuoba (North China craton), and that it persisted through the Phanerozoic orogenies. Moreover, despite the proximity to Phanerozoic subduction zones, the Khanka CLM shows little post-melting enrichment, e.g. the clinopyroxenes are typically LREE-depleted and have Sr-Nd isotope ratios typical of the MORB mantle. We posit that the metasomatism of the CLM, earlier proposed for North China xenolith suites and ascribed to the effects of Pacific or older subduction and related mantle upwelling, may not be widespread in the CAOB. In general, Proterozoic blocks composed of residual peridotites may be more common in the CLM of the SE Siberia and northern China, and possibly other orogenic belts, than previously thought.
DS201412-0964
2014
Guo, R.Wang, W., Liu, S., Santsh, M., Zhang, L., Bai, X., Zhao, Y., Zhang, S., Guo, R.1.23 Ga mafic dykes in the North Chin a craton and their implications for the reconstruction of the Columbia supercontinent.Gondwana Research, in press availableChinaSupercontinents
DS202006-0956
2020
Guo, R.Wang, K., Guo, R., Zhang, Y., Tian, Y.Photoluminescence and annealing of nitrogen-interstitials defects in electron irradiated diamond.Spectroscopy Letters, Vol. 53, 4, pp. 270-276.Globalluminescence

Abstract: There are a few studies reported in the literature describing the conversion of intrinsic defects but the involvement of nitrogen-interstitials in diamond has not been reported so far. In this paper, a detailed study on the conversion of nitrogen-interstitials in diamond during the irradiation and further annealing were presented by the micro-photoluminescence spectra. The results indicated that the interstitials were immobile until 300?°C and then escaped from the nitrogen capture, followed by migration and recombination with vacancies in the structure of nitrogen-vacancy and vacancy centers.
DS201112-0177
2011
Guo, S.Chen, Y., Ye, K., Guo, S., Liu, J.B.Metasomatic pyroxenites and peridotites in the mantle wedge: tracing he high Nb/Ta reservoir.Goldschmidt Conference 2011, abstract p.658.ChinaDabie Shan, deep recycled eclogites, UHP
DS201312-0347
2012
Guo, S.Guo, S., Ye, K., Wu, Y., Chen, Y., Yang, Y., Zhang, L., Liu, J., Mao, Q., Ma, Y.A potential method to confirm the previous existence of lawsonite in eclogite: the mass imbalance of Sr and LREEs in multi stage epidote ( Ganghe, Dabie UHP terrane).Journal of Metamorphic Gology, Vol. 31, 4, pp. 415-435.ChinaUHP
DS201609-1747
2016
Guo, S.Su, B., Chen, Y., Guo, S., Chu, Z-Y., Liu, J-B., Gao, Y-J.Carbonatitic metasomatism in orogenic dunites from Lijiatun in the Sulu UHP terrane, eastern China.Lithos, Vol. 262, pp. 266-284.ChinaCarbonatite

Abstract: Among orogenic peridotites, dunites suffer the weakest crustal metasomatism at the slab-mantle interface and are the best lithology to trace the origins of orogenic peridotites and their initial geodynamic processes. Petrological and geochemical investigations of the Lijiatun dunites from the Sulu ultrahigh-pressure (UHP) terrane indicate a complex petrogenetic history involving melt extraction and multistage metasomatism (carbonatitic melt and slab-derived fluid). The Lijiatun dunites consist mainly of olivine (Fo = 92.0-92.6, Ca = 42-115 ppm), porphyroblastic orthopyroxene (En = 91.8-92.8), Cr-spinel (Cr# = 50.4-73.0, TiO2 < 0.2 wt.%) and serpentine. They are characterized by refractory bulk-rock compositions with high MgO (45.31-47.07 wt.%) and Mg# (91.5-91.9), and low Al2O3 (0.48-0.70 wt.%), CaO (0.25-0.44 wt.%) and TiO2 (< 0.03 wt.%) contents. Whole-rock platinum group elements (PGE) are similar to those of cratonic mantle peridotites and Re-Os isotopic data suggest that dunites formed in the early Proterozoic (~ 2.2 Ga). These data indicate that the Lijiatun dunites were the residues of ~ 30% partial melting and were derived from the subcontinental lithospheric mantle (SCLM) beneath the North China craton (NCC). Subsequent carbonatitic metasomatism is characterized by the formation of olivine-rich (Fo = 91.6-92.6, Ca = 233-311 ppm), clinopyroxene-bearing (Mg# = 95.9-96.7, Ti/Eu = 104-838) veins cutting orthopyroxene porphyroblasts. Based on the occurrence of dolomite, mass-balance calculation and thermodynamic modeling, carbonatitic metasomatism had occurred within the shallow SCLM (low-P and high-T conditions) before dunites were incorporated into the continental subduction channel. These dunites then suffered weak metasomatism by slab-derived fluids, forming pargasitic amphibole after pyroxene. This work indicates that modification of the SCLM beneath the eastern margin of the NCC had already taken place before the Triassic continental subduction. Orogenic peridotites derived from such a lithospheric mantle wedge may be heterogeneously modified prior to their incorporation into the subduction channel, which would set up a barrier for investigation of the mass transfer from the subducted crust to the mantle wedge through orogenic peridotites.
DS201610-1912
2016
Guo, S.Su, B., Chen, Y., Guo, S., Chu, Z-Y., Liu, J-B., Gao, Y-J.Carbonatitic metasomatism in orogenic dunites from Lijiatun in the Sulu UHP terrane, eastern China.Lithos, Vol. 262, pp. 266-284.ChinaUHP, carbonatite

Abstract: Among orogenic peridotites, dunites suffer the weakest crustal metasomatism at the slab-mantle interface and are the best lithology to trace the origins of orogenic peridotites and their initial geodynamic processes. Petrological and geochemical investigations of the Lijiatun dunites from the Sulu ultrahigh-pressure (UHP) terrane indicate a complex petrogenetic history involving melt extraction and multistage metasomatism (carbonatitic melt and slab-derived fluid). The Lijiatun dunites consist mainly of olivine (Fo = 92.0-92.6, Ca = 42-115 ppm), porphyroblastic orthopyroxene (En = 91.8-92.8), Cr-spinel (Cr# = 50.4-73.0, TiO2 < 0.2 wt.%) and serpentine. They are characterized by refractory bulk-rock compositions with high MgO (45.31-47.07 wt.%) and Mg# (91.5-91.9), and low Al2O3 (0.48-0.70 wt.%), CaO (0.25-0.44 wt.%) and TiO2 (< 0.03 wt.%) contents. Whole-rock platinum group elements (PGE) are similar to those of cratonic mantle peridotites and Re-Os isotopic data suggest that dunites formed in the early Proterozoic (~ 2.2 Ga). These data indicate that the Lijiatun dunites were the residues of ~ 30% partial melting and were derived from the subcontinental lithospheric mantle (SCLM) beneath the North China craton (NCC). Subsequent carbonatitic metasomatism is characterized by the formation of olivine-rich (Fo = 91.6-92.6, Ca = 233-311 ppm), clinopyroxene-bearing (Mg# = 95.9-96.7, Ti/Eu = 104-838) veins cutting orthopyroxene porphyroblasts. Based on the occurrence of dolomite, mass-balance calculation and thermodynamic modeling, carbonatitic metasomatism had occurred within the shallow SCLM (low-P and high-T conditions) before dunites were incorporated into the continental subduction channel. These dunites then suffered weak metasomatism by slab-derived fluids, forming pargasitic amphibole after pyroxene. This work indicates that modification of the SCLM beneath the eastern margin of the NCC had already taken place before the Triassic continental subduction. Orogenic peridotites derived from such a lithospheric mantle wedge may be heterogeneously modified prior to their incorporation into the subduction channel, which would set up a barrier for investigation of the mas
DS201909-2093
2019
Guo, S.Su, B., Chen, Y., Mao, Q., Zhang, D., Jia, L-H., Guo, S.Minor elements in olivine inspect the petrogenesis of orogenic peridotites. Dabie -SuluLithos, Vol. 344-345, pp. 207-216.ChinaUHP
DS201910-2303
2019
Guo, S.Su, B., Chen, Y., Guo, S., Chen S., Li, Y.Garnetite and pyroxenite in the mantle wedge formed by slab mantle interactions at different melt/rock ratios.Journal of Geophysical Research: Solid Earth, Vol. 124, 7, pp. 6504-6522.Mantlesubduction

Abstract: Mantle wedge hybridization by crust?derived melt is a crucial mechanism responsible for arc lavas. However, how the melt?rock reactions proceed in the mantle wedge and affect melt compositions is poorly understood. Garnet peridotites from Jiangzhuang in the Sulu orogen (eastern China) host garnetite and pyroxenite veins formed by slab?mantle interactions at different melt/rock ratios. The Jiangzhuang peridotites consist mainly of garnet lherzolites and minor harzburgites and represent a fragment of the mantle wedge influenced by ultrahigh?pressure metamorphism (5.2-6.1 GPa) in the subduction channel. Petrography, major and trace element geochemistry, and in situ clinopyroxene Sr isotope values of the garnetite and pyroxenite veins reveal their derivation from interactions between mantle wedge peridotites and deeply subducted crust?derived melts. The two veins share a common metamorphic and metasomatic history and have similar mineral assemblages and compositions, enriched isotope signatures, and formation P?T conditions, indicating the same source for their reacting melts. The different mineral proportions and microtextures between the garnetite and pyroxenite veins are ascribed to different melt/rock ratios. The garnetite vein formed at relatively high melt/rock ratios (>1:1), which would likely produce hybrid slab melts with Mg?rich, high?silica adakitic signatures. In contrast, the pyroxenite vein formed at low melt/rock ratios (<1:1), and the expected hybrid slab melts would evolve into high?Mg andesites. Moreover, recycled heterogeneous garnetite and pyroxenite could contribute to the mantle sources of intraplate magmas. Therefore, slab?mantle interactions at different melt/rock ratios could be an important crustal input to lithological and geochemical heterogeneities in the mantle.
DS200512-1249
2005
Guo, T.Y.Zhang, S.Q., Mahoney, J.J., Mo, X.X., Ghazi, A.M., Milani, L., Crawford, A.J., Guo, T.Y., Zhao, Z.D.Evidence for a Wide spread Tethyan upper mantle with Indian - Ocean type isotopic characteristics.Journal of Petrology, Vol. 46, 4, pp. 829-858.Indian OceanGeochronology
DS201412-0220
2014
Guo, W.Eiler, J.M., Berquist, B., Bourg, I., Cartigny, P., Farquhar, J., Gagnon, A., Guo, W., Halevy, I., Hofman, A., larson, T.E., Levin, N., Schauble, E.A., Stolper, D.Frontiers of stable isotope geoscience.Chemical Geology, Vol. 372, pp. 119-143.TechnologyReview of isotopes
DS200512-1239
2005
Guo, W.L.Zhang, B., Guo, W.L., Dai, Y.T.Touch graphite and turn it into diamond? Physical mechanics of carbon matters under ultrahigh pressure.Physics Review Letters, Vol. 34, 7, pp. 498-502.TechnologyCarbon
DS1990-0617
1990
Guo, W.X.Guo, W.X., Friedman, I., Gleason, J.Natural occurrence of silicon carbide in a Diamondiferous kimberlite fromFuxianNature, Vol. 346, No. 6282, July 26, pp. 352-354ChinaSilicon carbide, Mineralogy
DS201212-0271
2012
Guo, X.Guo, X., Encarnacion, J., Deino, A., Xu, X., Li, Z., Tian, X.Collision and rotation of the South Chin a block and their role in the formation and exhumation of ultrahigh pressure rocks in the Dabie Shan orogen.Terra Nova, in press availableChinaUHP
DS201212-0272
2012
Guo, X.Guo, X., Encarnacion, J., Xu, X., Deino, A., Li, Z.,Tian, X.Collision and rotation of the South Chin a block and their role in the formation and exhumation of ultrahigh pressure rocks in the Dabie Shan orogen.Terra Nova, Vol. 24, 5, pp. 339-350.ChinaUHP
DS201605-0921
2016
Guo, X.Xie, Y., Hou, Z., Goldfarb, R.J., Guo, X., Wang, L.Rare earth element deposits in China.SEG Reviews in Economic Geology, editors Verplanck, P.L., Hitzman, M.W., No. 18, pp. 115-136.ChinaBayan Obo, Maoniuping
DS201702-0253
2016
Guo, X.Xie, Y., Hou, Z., Goldfarb, R.J., Guo, X., Wang, L.Rare earth element deposits in China.Reviews in Economic Geology, Vol. 18, pp. 115-136.ChinaREE deposits

Abstract: China is the world’s leading rare earth element (REE) producer and hosts a variety of deposit types. Carbonatite-related REE deposits, the most significant deposit type, include two giant deposits presently being mined in China, Bayan Obo and Maoniuping, the first and third largest deposits of this type in the world, respectively. The carbonatite-related deposits host the majority of China’s REE resource and are the primary supplier of the world’s light REE. The REE-bearing clay deposits, or ion adsorption-type deposits, are second in importance and are the main source in China for heavy REE resources. Other REE resources include those within monazite or xenotime placers, beach placers, alkaline granites, pegmatites, and hydrothermal veins, as well as some additional deposit types in which REE are recovered as by-products. Carbonatite-related REE deposits in China occur along craton margins, both in rifts (e.g., Bayan Obo) and in reactivated transpressional margins (e.g., Maoniuping). They comprise those along the northern, eastern, and southern margins of the North China block, and along the western margin of the Yangtze block. Major structural features along the craton margins provide first-order controls for REE-related Proterozoic to Cenozoic carbonatite alkaline complexes; these are emplaced in continental margin rifts or strike-slip faults. The ion adsorption-type REE deposits, mainly situated in the South China block, are genetically linked to the weathering of granite and, less commonly, volcanic rocks and lamprophyres. Indosinian (early Mesozoic) and Yanshanian (late Mesozoic) granites are the most important parent rocks for these REE deposits, although Caledonian (early Paleozoic) granites are also of local importance. The primary REE enrichment is hosted in various mineral phases in the igneous rocks and, during the weathering process, the REE are released and adsorbed by clay minerals in the weathering profile. Currently, these REE-rich clays are primarily mined from open-pit operations in southern China. The complex geologic evolution of China’s Precambrian blocks, particularly the long-term subduction of ocean crust below the North and South China blocks, enabled recycling of REE-rich pelagic sediments into mantle lithosphere. This resulted in the REE-enriched nature of the mantle below the Precambrian cratons, which were reactivated and thus essentially decratonized during various tectonic episodes throughout the Proterozoic and Phanerozoic. Deep fault zones within and along the edges of the blocks, including continental rifts and strike-slip faults, provided pathways for upwelling of mantle material.
DS202006-0957
2016
Guo, X.Xie, Y., Hou, Z., Goldfarb, R.J., Guo, X., Wang, L.Rare Earth element deposits in China.SEG Reviews In Economic Geology Chapter 6, Vol. 18, pp. 115-136.ChinaREE

Abstract: China is the world’s leading rare earth element (REE) producer and hosts a variety of deposit types. Carbonatite- related REE deposits, the most significant deposit type, include two giant deposits presently being mined in China, Bayan Obo and Maoniuping, the first and third largest deposits of this type in the world, respectively. The carbonatite-related deposits host the majority of China’s REE resource and are the primary supplier of the world’s light REE. The REE-bearing clay deposits, or ion adsorption-type deposits, are second in importance and are the main source in China for heavy REE resources. Other REE resources include those within monazite or xenotime placers, beach placers, alkaline granites, pegmatites, and hydrothermal veins, as well as some additional deposit types in which REE are recovered as by-products. Carbonatite-related REE deposits in China occur along craton margins, both in rifts (e.g., Bayan Obo) and in reactivated transpressional margins (e.g., Maoniuping). They comprise those along the northern, eastern, and southern margins of the North China block, and along the western margin of the Yangtze block. Major structural features along the craton margins provide first-order controls for REE-related Proterozoic to Cenozoic carbonatite alkaline complexes; these are emplaced in continental margin rifts or strike-slip faults. The ion adsorption-type REE deposits, mainly situated in the South China block, are genetically linked to the weathering of granite and, less commonly, volcanic rocks and lamprophyres. Indosinian (early Mesozoic) and Yanshanian (late Mesozoic) granites are the most important parent rocks for these REE deposits, although Caledonian (early Paleozoic) granites are also of local importance. The primary REE enrichment is hosted in various mineral phases in the igneous rocks and, during the weathering process, the REE are released and adsorbed by clay minerals in the weathering profile. Currently, these REE-rich clays are primarily mined from open-pit operations in southern China. The complex geologic evolution of China’s Precambrian blocks, particularly the long-term subduction of ocean crust below the North and South China blocks, enabled recycling of REE-rich pelagic sediments into mantle lithosphere. This resulted in the REE-enriched nature of the mantle below the Precambrian cratons, which were reactivated and thus essentially decratonized during various tectonic episodes throughout the Proterozoic and Phanerozoic. Deep fault zones within and along the edges of the blocks, including continental rifts and strike-slip faults, provided pathways for upwelling of mantle material.
DS1995-0580
1995
Guo, X-M.Gao, S., Zhang, B.R., Guo, X-M.Silurian Devonian provenance changes of South Qinling Basins: implicationfor accretion of Yangtze craton.Tectonophysics, Vol. 250, No. 1/3, Nov. 15, pp. 183-ChinaCraton, North China
DS202109-1485
2021
Guo, Y.Qiu, Y., Guo, Y.Explaining colour change in pyrope-spessartine garnets.MDPI Minerals, Vol. 11, 11080865 15p. PdfglobalFTIR

Abstract: A colour-changing garnet exhibits the "alexandrite effect", whereby its colour changes from green in the presence of daylight to purplish red under incandescent light. This study examines this species of garnets as well as the causes of the colour change by using infrared and ultraviolet visible (UV-Vis) spectroscopy. The infrared spectra show that the colour-changing garnets in this paper belong to the solid solution of pyrope-spessartine type. CIE1931 XYZ colour matching functions are used to calculate the colour parameters influencing garnet colour-changing under different light sources. The UV-Vis spectra show two zones of transmittance, in the red region at 650-700 nm and the blue-green region at 460-510 nm. As they exhibit the same capacity to transmit light, the colour of the gem is determined by the external light source. The absorption bands of Cr3+ and V3+ at 574 nm in the UV-Vis spectra are the main cause of the change in colour. With the increase in the area of peak absorption, the differences in the chroma and colour of the garnet gradually increase in daylight and incandescent light, and it exhibits a more prominent colour-changing effect.
DS202110-1622
2020
Guo, Y.Liu, F., Guo, Y., Lv, S., Chen, G.Application of the entropy method and color difference formula to the evaluation of round brilliant cut diamond scintillation.Mathematics, Vol. 8, 9, doi.org/10.3390/ math8091489globaldiamond cutting

Abstract: A modeling approach combining the entropy method and color difference formula is proposed in order to quantitatively evaluate diamond scintillation. The images of 66 diamonds were captured from 0° to 105° rotation at 15° intervals. The color difference of corresponding pixels in adjacent rotation angle images was calculated using a MatLab r2014a program, which indicated the diamond’s color change due to its scintillation. A threshold (10) was determined to divide the color difference into seven color difference intervals, the percentage of which indicated the color-change area. The color difference and the percentage were comprehensively analyzed using the entropy method to evaluate diamond scintillation objectively and quantitatively. Lightness was the main factor affecting the diamond scintillation while chroma and hue also significantly affected it.
DS200512-0381
2004
Guo, Z.Guo, Z., Hertogen, J., Liu, J., Pasteels, P., Vocen, A.Potassic magmatism in western Sichuan and Yunnan Provinces, SE Tibet, China: petrological and geochemical constraints on petrogenesis.Journal of Petrology, Vol. 46, 1-2, pp. 33-78.China, TibetMagmatism
DS200612-0513
2006
Guo, Z.Guo, Z., Wilson, M., Liu, J., Mao, Q.Post collisional, potassic and ultrapotassic magmatism of the northern Tibetan Plateau: constraints on characteristics of the mantle source, geodynamic upliftJournal of Petrology, Vol. 47, 6, pp. 1177-1220.Asia, TibetMagmatism - not specific to diamonds
DS201609-1756
2016
Guo, Z.Zhang, M., Guo, Z.Origin of Late Cenozoic Abaga - Dalinuoer basalts, eastern China: implications for a mixed pyroxenite- peridotite source related with deep subduction of the Pacific slab.Gondwana Research, Vol. 37, pp. 130-151.ChinaPeridotite

Abstract: Continental intraplate basalts (15.42-0.16 Ma) from Abaga-Dalinuoer volcanic field (ADVF) in central Inner Mongolia of eastern China, as a part of Cenozoic volcanic province along eastern margin of the Eurasian continent, provide a good opportunity to explore potential links between deep subduction of the Pacific slab and continental intraplate volcanism. In this study, we report an integrated dataset of whole-rock K-Ar ages, major and trace elements and Sr-Nd-Pb isotopes, and olivine major and minor elements for the Abaga-Dalinuoer basalts (ADBs), and propose that mantle source lithology of the ADB magmas may consist of both pyroxenite and peridotite. The ADBs display low SiO2 (42.3-50.2 wt.%), high MgO (7.3-11.4 wt.%) and moderate K2O + Na2O (3.8-6.4 wt.%), and can be subdivided into basanites, alkali basalts and tholeiitic basalts that are all characterized by ocean island basalt (OIB)-like rare earth elements (REE) and enrichment in both large ion lithosphile elements (LILE) and high field strength elements (HFSE). Olivine phenocrysts have higher Ni and Fe/Mn and lower Mn, Ca and Ca/Fe relative to those from peridotite melts, but exhibit clearly lower Ni contents (< 2500 ppm) compared with expected Ni range (> 3000 ppm) for olivines crystallized from olivine-free pyroxenite melts. Estimated compositions of the ADB primary magmas, together with olivine compositions, suggest an iron-rich mantle source related with silica-deficient pyroxenite that is most likely derived from deeply subducted Pacific oceanic crust. Additionally, peridotite and recent subducted sediments are also required to account for high Ni and MgO in primary magmas together with their trace elements and Sr-Nd-Pb isotope systematics. We suggest that a mixed pyroxenite-peridotite source lithology can better match observed whole-rock and olivine signatures in the ADB, compared with either peridotite only or olivine-free pyroxenite only source lithology. In our model, pyroxenite melts would either react with or mechanically mix with peridotite, and the proportion of pyroxenite melts may range from 30% to 45% for mechanical mixing scenario. A continuous spectrum from tholeiitic to alkali melts revealed by melt-peridotite reaction experiment can explain formation of primary magmas of basanites, alkali basalts and tholeiitic basalts by increasing melting degree of a similar mantle source. Relatively higher 206Pb/204Pb of the ADB may suggest more significant role of recent (< 0.5 Ga) subducted Pacific oceanic materials, in contrast to other Cenozoic basalts in eastern China (e.g., Changbai basalts) that exhibit varying contributions from ancient (> 1.5 Ga) subducted continental sediments. We emphasize that coupled geochemical and geodynamic links (i.e., subduction polarity) between deeply subducted Pacific slab and continental intraplate volcanism in eastern China may exist, which directly support the involvement of deeply subducted Pacific materials in petrogenesis of the ADB. From the perspective of plate motion kinetics, decompression partial melting of upwelling fragmented Pacific slab (silica-deficient pyroxenite + recent subducted sediments) may be triggered by rollback of deeply subducted Pacific slab during Late Cenozoic times. Continental intraplate volcanism in the ADVF generally started with termination of opening of the Japan Sea, suggesting that deep subduction of the Pacific slab may have been an important geodynamic mechanism responsible for tectono-magmatic evolution of northeastern Asia. We suggest that the ADBs have the potential to shed light on genetic links between continental intraplate volcanism and deep subduction of the Pacific slab in geochemical and geodynamic processes.
DS201702-0254
2017
Guo, Z.Xu, B., Griffin, W.L., Xiong, Q., Hou, Z-Q, O'Reilly, S.Y., Guo, Z., Pearson, N.J., Greau, Y., Yang, Z-M., Zheng, Y-C.Ultrapotassic rocks and xenoliths from South Tibet: contrasting styles of interaction between lithospheric mantle and asthenosphere during continental collision.Geology, Vol. 45, 1, pp. 51-54.China, TibetUPR - metasomatism

Abstract: Widespread Miocene (24-8 Ma) ultrapotassic rocks and their entrained xenoliths provide information on the composition, structure, and thermal state of the sub-continental lithospheric mantle in southern Tibet during the India-Asia continental collision. The ultrapotassic rocks along the Lhasa block delineate two distinct lithospheric domains with different histories of depletion and enrichment. The eastern ultrapotassic rocks (89°E-92°E) reveal a depleted, young, and fertile lithospheric mantle (87Sr/86Srt = 0.704-0.707 [t is eruption time]; Hf depleted-mantle model age [TDM] = 377-653 Ma). The western ultrapotassic rocks (79°E-89°E) and their peridotite xenoliths (81°E) reflect a refractory harzburgitic mantle refertilized by ancient metasomatism (lavas: 87Sr/86Srt = 0.714-0.734; peridotites: 87Sr/86Srt = 0.709-0.716). These data integrated with seismic tomography suggest that upwelling asthenosphere was diverted away from the deep continental root beneath the western Lhasa block, but rose to shallower depths beneath a thinner lithosphere in the eastern part. Heating of the lithospheric mantle by the rising asthenosphere ultimately generated the ultrapotassic rocks with regionally distinct geochemical signatures reflecting the different nature of the lithospheric mantle.
DS1992-0242
1992
Guo J.G., Chen J.C.Chen, F., Guo J.G., Chen J.C., Liu, C.R.1st discovery of high pressureotassium and high chlorine inclusions indiamonds.*CHIChinese Science Bulletin, *CHI, Vol. 37, No. 18, September pp. 1557-1560. # JU464ChinaDiamond inclusions, Potassium, Chlorine
DS1986-0119
1986
Guo JiugaoCai Xiucheng, Guo Jiugao, Chen Feng, Fu Yude, Tang Rongbing, TanDistribution of paramagnetic nitrogen in placer diamonds with specialAcad. Sin. Institute Geochem., Guiyang, *CHI, Vol. 6, No. 3, September pp. 195-202ChinaAlluvials, Geochemistry, diamond inclusions
DS1986-0120
1986
Guo JiugaoCai Xiucheng, Guo Jiugao, Chen, Feng, Fu, Yude, Tang Rongbing, TanDistribution of paramagnetic nitrogen in placer diamonds with Special reference to its significance in diamond classification. *CHIKuangwu Xuebao, *CHI, Vol. 6, No. 3, pp. 195-202ChinaAlluvials, Diamond inclusions-nitrog
DS1990-0613
1990
Guo JiugaoGuo Jiugao, Chen Feng, Cai Xiucheng, Deng HuaxingSpectroscopic study of natural diamonds in ChinaChinese Journal of Geochemistry, (in English), Vol. 9, No. 2, pp. 161-168ChinaDiamond morphology spectroscopy, Natural diamonds
DS1990-0614
1990
Guo LiheGuo Lihe, Wang Wuyi, Wang Alian, Zhang AndiInfrared spectroscopic study of pyropeInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 427-429ChinaSpectroscopy, Pyrope
DS1990-1534
1990
Guo LiheWang Alian, Dhamelincourt, P., Guo Lihe, Wang Wuyi, Zhang AndiThe micro-structural variance in some minerals of the earth's mantle-revealed through micro-raman spectroscopyInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 495-496ChinaMicroscopy, Kimberlites, pyrope
DS1990-1536
1990
Guo LiheWang Wuyi, Guo Lihe, Wang Alian, Zhang AndiA study of hydrous component in pyropeInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 497-498ChinaMicroscopy, Pyrope
DS1990-1624
1990
Guo LiheZhang Andi, Meyer, H.O.A., Guo Lihe, Zhou Jianxiong, Xie Xilin, Wang Alian, XuComparative study of inclusions in diamonds with macrocrysts From kimberlites in north Chin a cratonInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 504-505ChinaDiamond inclusions, Macrocrysts
DS1991-1925
1991
Guo LiheZhang Andi, Xu Dehuan, Xie Xiing, Guo Lihe, Zhou Jianzong, Wang WuyiThe status and future of diamond exploration in ChinaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 10-12China, Russia, Australia, South AfricaSinokorean, Yangtze, Tarim, Fuxiam, Tieling, Huanren, Mengyi, Lamproites
DS1991-1931
1991
Guo LiheZhou Jianxiong, Zhang Andi, Wang Wuyi, Xie Xilin, Guo LiheSpinel - as indicator for diamondProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 208-211ChinaSpinel -compositional range table, Geochemistry
DS1994-0675
1994
Guo LiheGuo Lihe, Wang Alian, Wang Wuyi, Zhang AndiInfrared spectroscopic characteristics of garnets and spinels - a potential discriminative tool for diamond exploration.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 357-365.ChinaGeothermometry, Diamond exploration
DS1990-1607
1990
Guo WenxiangYang Jianjun, Guo WenxiangStudy of a unique eclogitic inclusion in the kimberlite in Shandong, EastChinaInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 502-504ChinaEclogite, Inclusions
DS1989-0557
1989
Guo XiancaiGuo XiancaiThe geological features and the genesis of the Dashigou ultrabasic rock; carbonatite impurity rock bodies in Huxian Shaanxi.*CHIGeology of Shaanxi, *CHI, Vol. 7, No. 1, June pp. 42-51ChinaPetrology, Carbonatite
DS1990-0409
1990
Guo YapingDobbs, P.N., Guo Yaping, Hu Siyi, Lin Jianrong, Luo Lianquan, ZangA sedimentological study of Diamondiferous Quaternary sediments in southern Shandong ChinaGeol. Journal, Vol. 25, pp. 47-59ChinaSedimentology, Diamond sediments
DS1990-1626
1990
Guo YueminZhao Donggao, Huang Yunhui, Guo YueminSerpentine -group minerals in Shandong kimberlitesInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 829-831ChinaSerpentinites, Shandong -kimberlites
DS1987-0261
1987
Guo ZongshanGuo ZongshanOrigin and prospecting methods of diamond.*CHIInstitute Miner. Deposits Chin. Acad. Geol. Sci. Beijing, *CHI, Vol. 19, pp. 65-73ChinaDiamond prospecting, Overview
DS1995-1423
1995
GuocehngPan, GuocehngRelated information measures for the associations of earth sciencevariablesMathematical Geology, Vol. 27, No. 5, pp. 609-632GlobalGeostatistics
DS2003-1556
2003
Guochao, Z.Zhaochong, Z., Jingwen, M., Robinson, P.T., Zhou, M.F., Guochao, Z., JianminThe Aoyougou mafic ultramafic complex in the North Qilian Mountains northwestInternational Geology Review, Vol. 45, 9, pp. 841-856.China, northwestMagmatism
DS200412-2221
2003
Guochao, Z.Zhaochong, Z., Jingwen, M., Robinson, P.T., Zhou, M.F., Guochao, Z., Jianmin, Y., Zhiliang, W., Zuoheng, Z.The Aoyougou mafic ultramafic complex in the North Qilian Mountains northwest China: a possible middle Proterozoic ophiolite aloInternational Geology Review, Vol. 45, 9, pp. 841-856.ChinaMagmatism
DS1993-1184
1993
GuochengPan, GuochengCanonical favourability model for dat a integration and mineral potentialmappingComputers and Geosciences, Vol. 19, No. 8, pp. 1077-1100GlobalProgram -CFM, Mineral potential mapping
DS1990-0618
1990
Guocheng PanGuocheng Pan, Harris, D.P.Three nonparametric techniques for the optimum discretization of quantitative geological variablesMath. Geol, Vol. 22, No. 6, pp. 699-722GlobalGeostatistics, Nonparametric techniques
DS1991-0627
1991
Guocheng PanGuocheng Pan, Harris, D.P.A new multidimensional scaling technique based upon associations of triple objects -Pijk and its application to the analysis of geochemical dataMath. Geol, Vol. 23, No. 6, August pp. 861-886GlobalGeostatistics, Geochemistry
DS1991-0628
1991
Guocheng PanGuocheng Pan, Harris, D.P.Geology -exploration endowment models for simultaneous estimation of discoverable mineral resources and endowmentMathematical Geology, Vol. 23, No. 4 May pp. 507-540GlobalMineral resources, Models
DS1992-0630
1992
Guocheng PanGuocheng Pan, Harris, D.P.Decomposed and weighted characteristic analysis for the quantitative estimation of mineral resourcesMathematical Geology, Vol. 24, No. 7, pp. 807-824ChinaGeostatistics, Pegmatites
DS1992-0631
1992
Guocheng PanGuocheng Pan, Harris, D.P.Delineation in intrinsic unitsMathematical Geology, Vol. 25, No. 1, January pp. 9-40GlobalGeostatistics, Computer Program
DS1992-0632
1992
Guocheng PanGuocheng Pan, Harris, D.P.Estimating a favourability equation for the integration of geodat a and selection of mineral exploration targetsMathematical Geology, Vol. 24, No. 2, February pp. 177-202GlobalGeostatistics, Mineral exploration targets
DS1992-0633
1992
Guocheng PanGuocheng Pan, Moss, K., Heiner, T., Carr, J.R.A fortran program for three-dimensional cokriging with case demonstrationComputers and Geosciences, Vol. 18, No. 5, pp. 557-578GlobalGeostatistics, Program -cokriging
DS1993-0593
1993
Guocheng PanGuocheng Pan, Arik, A.Restricted kriging for mixture of grade modelsMathematical Geology, Vol. 25, No. 6, August pp. 713-736GlobalGeostatistics, Ore reserves, grades
DS1994-0677
1994
Guocheng PanGuocheng PanRestricted kriging: a link between sample value and sample configurationMathematical Geology, Vol. 26, No. 1, pp. 135-155GlobalGeostatistics, Kriging
DS1989-0257
1989
GuodaChen, GuodaTectonics of Chin a #1International Academic Publishers, 266p. $ 56.00 United States approx. Due Jan. 1989ChinaBook -ad, Tectonics
DS202010-1838
2020
Guodong, Z.Deng, L., Geng, X., Liu, Y., Zong, K., Zhu, L., Zhengwei, L., Hu, Z., Guodong, Z., Guangfu, C.Lithospheric modification by carbonatitic to alkaline melts and deep carbon cycle: insights from peridotite xenoliths of eastern China.Lithos, in press available 38p. PdfChinacarbonatite

Abstract: Carbonates in subducting oceanic slabs can survive beyond slab dehydration and be transferred into the deep mantle. Such deep carbon cycling plays a critical role in generating carbonatitic to alkaline melts. However, whether and how this process has influenced the lithospheric mantle still remains enigmatic. To address these issues, here we provide a detailed petrographic, in-situ chemical and Sr isotopic study on two mantle xenoliths (a wehrlite and a melt pocket-bearing peridotite) entrained by the Changle Miocene basalts from the eastern China. The Changle wehrlite contains carbonate melt inclusions and apatites and is merely enriched in clinopyroxene relative to the lherzolites. The clinopyroxenes are characterized by high (La/Yb)N (4.7-41) and low Ti/Eu (873-2292) ratios and equilibrated with carbonated silicate melt-like compositions. These petrographic and chemical features indicate that the wehrlite was formed by reaction between peridotite and carbonated silicate melts. On the other hand, the Changle melt pocket-bearing peridotite is suggested to have been produced by in-situ melting/breakdown of amphiboles of an amphibole-rich dunite. Low olivine Fo (~89), presence of amphiboles with high (La/Yb)N (~50) and low Ti/Eu (~1070) ratios suggest that such amphibole-rich dunite would have been formed by reaction of peridotite with hydrous alkaline basaltic melts from a carbonated mantle. Our data, combined with previously reported data of the Changle lherzolite xenoliths, unravel a series of mantle metasomatisms by carbonatitic to alkaline melts from carbonated mantle sources. The consistently high 87Sr/86Sr ratios (up to 0.7036) of the clinopyroxenes in both the wehrlites and lherzolites indicate the carbonate components in the mantle sources were derived from the stagnant Pacific slab within the Mantle Transition Zone. This study provides a fresh perspective on the role of deep carbon cycling from subducted oceanic slabs in chemical modification of intracontinental lithospheric mantle through reaction with different types of melts.
DS2000-0064
2000
Guodu, L.Basharin, A.K., Belyaev, S.Y., Guodu, L.Riphean Phanerozoic tectonics and evolution of the Yenisei Baikit region of Siberian Craton and Tarim...Russian Geology and Geophysics, Vol. 41, No. 4, pp. 468-77.Russia, SiberiaTectonics, Petroleum emphasis - not specific to diamonds
DS1992-0077
1992
Guohan, Y.Baolei, M., Guohan, Y.Geological features of Triassic alkaline and subalkaline igneous complexes in the Yan-Liao areaActa Geologica Sinica, Vol. 5, No. 4, December pp. 339-355ChinaAlkaline rocks, Geochemistry
DS201810-2326
2018
Guotana, J.M.Guotana, J.M., Morishita, T., Yamaguchi, R., Nishio, I., Tamura, A., Tani, K., Harigane, Y., Szilas, K., Pearson, D.G.Contrasting textural and chemical signatures of chromitites in the Mesoarchean Ulamertoq peridotite body, southern West Greenland.MDPI Geosciences, Researchgate 19p.Europe, Greenlandperidotite

Abstract: Peridotites occur as lensoid bodies within the Mesoarchaean orthogneiss in the Akia terrane of Southern West Greenland. The Ulamertoq peridotite body is the largest of these peridotites hosted within the regional orthogneiss. It consists mainly of olivine, orthopyroxene, and amphibole-rich ultramafic rocks exhibiting metamorphic textural and chemical features. Chromitite layers from different localities in Ulamertoq show contrasting characteristics. In one locality, zoned chromites are hosted in orthopyroxene-amphibole peridotites. Compositional zonation in chromites is evident with decreasing Cr and Fe content from core to rim, while Al and Mg increase. Homogeneous chromites from another locality are fairly uniform and Fe-rich. The mineral chemistry of the major and accessory phases shows metamorphic signatures. Inferred temperature conditions suggest that the zoned chromites, homogeneous chromites, and their hosts are equilibrated at different metamorphic conditions. In this paper, various mechanisms during the cumulus to subsolidus stages are explored in order to understand the origin of the two contrasting types of chromites.
DS201811-2575
2018
Guotana, J.M.Guotana, J.M., Morishita, T., Yamaguchi, R., Nishio, I., Tamura, A., Harigane, Y., Szilas, K., Pearson, G.Contrasting textural and chemical signatures of chromitites in the Mesoarchean Ulamertoq peridotite body, southern West Greenland.Geosciences, Vol. 8, no. 9, p. 328-Europe, Greenlandperidotite

Abstract: Peridotites occur as lensoid bodies within the Mesoarchaean orthogneiss in the Akia terrane of Southern West Greenland. The Ulamertoq peridotite body is the largest of these peridotites hosted within the regional orthogneiss. It consists mainly of olivine, orthopyroxene, and amphibole-rich ultramafic rocks exhibiting metamorphic textural and chemical features. Chromitite layers from different localities in Ulamertoq show contrasting characteristics. In one locality, zoned chromites are hosted in orthopyroxene-amphibole peridotites. Compositional zonation in chromites is evident with decreasing Cr and Fe content from core to rim, while Al and Mg increase. Homogeneous chromites from another locality are fairly uniform and Fe-rich. The mineral chemistry of the major and accessory phases shows metamorphic signatures. Inferred temperature conditions suggest that the zoned chromites, homogeneous chromites, and their hosts are equilibrated at different metamorphic conditions. In this paper, various mechanisms during the cumulus to subsolidus stages are explored in order to understand the origin of the two contrasting types of chromites.
DS201905-1037
2019
Guotana, J.M.Guotana, J.M., Morishita, T., Yamaguschi, R., Nishio, I., Tamura, A., Tani, K., Harigane, Y., Szilas, K., Pearson, D.G.Contrasting textural and chemical signatures of chromitites in the Mesoarchean Ulamertoq peridotite body, southern west Greenland.Geosciences ( MDPI), Vol. 8, 328- 19p.Europe, Greenlandchromitite

Abstract: Peridotites occur as lensoid bodies within the Mesoarchaean orthogneiss in the Akia terrane of Southern West Greenland. The Ulamertoq peridotite body is the largest of these peridotites hosted within the regional orthogneiss. It consists mainly of olivine, orthopyroxene, and amphibole-rich ultramafic rocks exhibiting metamorphic textural and chemical features. Chromitite layers from different localities in Ulamertoq show contrasting characteristics. In one locality, zoned chromites are hosted in orthopyroxene-amphibole peridotites. Compositional zonation in chromites is evident with decreasing Cr and Fe content from core to rim, while Al and Mg increase. Homogeneous chromites from another locality are fairly uniform and Fe-rich. The mineral chemistry of the major and accessory phases shows metamorphic signatures. Inferred temperature conditions suggest that the zoned chromites, homogeneous chromites, and their hosts are equilibrated at different metamorphic conditions. In this paper, various mechanisms during the cumulus to subsolidus stages are explored in order to understand the origin of the two contrasting types of chromites.
DS201905-1064
2019
Guotana, J.M.Nishio, I., Morishita, T., Szilas, K., Pearson, G., Tani, K-I., Tamura, A., Harigane, Y., Guotana, J.M.Titanium clinohumite bearing peridotite from the Ulamertoq ultramafic body in the 3.0 Ga Akia terrane of southern west Greenland.Geosciences ( MDPI), 20p. Europe, Greenlandperidotite

Abstract: A titanian clinohumite-bearing dunite was recently found in the Ulamertoq ultramafic body within the 3.0 Ga Akia Terrane of southern West Greenland. Titanian clinohumite occurs as disseminated and discrete grains. Titanian clinohumite contains relatively high amounts of fluorine, reaching up to 2.4 wt.%. The high-Fo content of olivine (Fo93) coupled with low Cr/(Cr + Al) ratio of orthopyroxene implies that the dunite host is not of residual origin after melt extraction by partial melting of the primitive mantle. Olivine grains are classified into two types based on abundances of opaque mineral inclusions: (1) dusty inclusion-rich and (2) clear inclusion-free olivines. Opaque inclusions in coarse-grained olivines are mainly magnetite. Small amounts of ilmenite are also present around titanian clinohumite grains. The observed mineral association indicates partial replacement of titanian clinohumite to ilmenite (+magnetite) and olivine following the reaction: titanian clinohumite = ilmenite + olivine + hydrous fluid. The coexistence of F-bearing titanian clinohumite, olivine, and chromian chlorite indicates equilibration at around 800-900 °C under garnet-free conditions (<2 GPa). Petrological and mineralogical characteristics of the studied titanian clinohumite-bearing dunite are comparable to deserpentinized peridotites derived from former serpentinites. This study demonstrates the importance of considering the effects of hydration/dehydration processes for the origin of ultramafic bodies found in polymetamorphic Archaean terranes.
DS201707-1332
2016
Guowu, L.Guowu, L., Guangming, Y., Fude, L., Ming, X., Xiangkun, G., Baoming, P., Fourestier, J.Fluorcalciopyrochlore, a new mineral species from Bayan Obo, inner Mongolia, P.R. China.The Canadian Mineralogist, Vol. 54, pp. 1285-1291.China, Mongoliacarbonatite - Bayan Obo

Abstract: Fluorcalciopyrochlore, ideally (Ca,Na)2Nb2O6F, cubic, is a new mineral species (IMA2013-055) occurring in the Bayan Obo Fe-Nb-REE deposit, Inner Mongolia, People's Republic of China. The mineral is found in a dolomite-type niobium rare-earth ore deposit. Associated minerals are dolomite, aegirine, riebeckite, diopside, fluorite, baryte, phlogopite, britholite-(Ce), bastnäsite-(Ce), zircon, magnetite, pyrite, fersmite, columbite-(Fe), monazite-(Ce), rutile, and others. Crystals mostly form as octahedra {111}, dodecahedra {110}, and cubes {100}, or combinations thereof, and generally range in size from 0.01 to 0.3 mm. It is brownish-yellow to reddish-orange in color with a light yellow streak. Crystals of fluorcalciopyrochlore are translucent to transparent with an adamantine to greasy luster on fractured surfaces. It has a conchoidal fracture. No parting or cleavage was observed. The Mohs hardness is 5, and the calculated density is 4.34(1) g/cm3. The empirical formula is (Ca1.14Na0.74Ce0.06Sr0.03Th0.01Fe0.01Y0.01La0.01Nd0.01)?2.02(Nb1.68Ti0.29Zr0.02Sn0.01)?2.00O6.00(F0.92O0.08)?1.00 on the basis of 7(O,F) anions pfu. The simplified formula is (Ca,Na)2Nb2O6F. The strongest four reflections in the X-ray powder-diffraction pattern [d in Å (I) hkl] are: 6.040 (9) 1 1 1, 3.017 (100) 2 2 2, 2.613 (17) 0 0 4, 1.843 (29) 0 4 4, and 1.571 (15) 2 2 6. The unit-cell parameters are a 10.4164(9) Å, V 1130.2(2) Å3, Z = 8. The structure was solved and refined in space group FdEmbedded Image m with R = 0.05. The type material is deposited in the Geological Museum of China, Beijing, People's Republic of China, catalogue number M12182.
DS2001-0499
2001
GuozeIchiki, M., Uyeshima, M., Utada, Guoze, Zi, MingzhiUpper mantle conductivity structure of the back arc region beneath northeastern ChinaGeophysical Research Letters, Vol. 28, No. 19, Oct. 1, pp. 3773-76.China, northeastTectonics
DS1992-0634
1992
Guozhi CuiGuozhi Cui, Shaode YaoTentative study on the principle of radio resonant separation of Kimberlite and its wall rock.International Journal of Mineral Processing, Vol. 34, pp. 177-183.ChinaMineral processing, Deposit -East China Diamond Mine No. 1 vein
DS1970-0300
1971
Guppy, D.J.Guppy, D.J., Brett, R., Milton, D.J.Liverpool and Strangways Craters, Northern Territory. Two Structures of Probable Impact Origin.Journal of Geophysical Research, Vol. 78, No. 23, PP. 5387-5393.Australia, Northern TerritoryCryptoexplosion, Kimberlite
DS1998-1531
1998
GuptaVeena, K., Paney. Krishnamurthy, Guptalead, Strontium, and neodymium isotopic systematics of the carbonatites of Sung Valley, Meghalaya, implications for plume...Journal of Petrology, Vol. 39, No. 11-12, Nov-Dec. pp. 1875-84.India, northeastCarbonatite - geochronology, Mantle - plume sources, characteristics
DS1992-0635
1992
Gupta, A.Gupta, A.Integrated study of Land sat imagery and aeromagnetic anomaly dat a for regional geological appraisal of parts of the Indian PeninsulaIndian Minerals, Vol. 46, No. 1, January-March pp. 53-76IndiaRemote sensing, Geophysics -aeromagnetic
DS2002-1402
2002
Gupta, A.Sashdharan, K., Mohanty, A.K., Gupta, A.A note on the diamond incidence in Wairagargh area, Garchiroli district MaharashtraJournal of Geological Society of India, Vol. 59,No.3,pp. 265-8.IndiaMineralogy
DS2002-1404
2002
Gupta, A.Sashidharan, K., Mohanty, A.K., Gupta, A.A note on the diamond incidence in Wairagargh area, Garchiroli district Maharashtra.Journal of the Geological Society of India, Vol. 59, March, pp. 265-268.IndiaDiamond morphology
DS2002-1405
2002
Gupta, A.Sashidharan, K., Mohanty, A.K., Gupta, A.A note on the diamond incidence in Wairagarh area, Garhchiroli district, MaharashtraJournal Geological Society of India, Vol. 59, pp. 265-8.IndiaDiamond occurrence
DS2002-1406
2002
Gupta, A.Sashidharan, K., Mohanty, A.K., Gupta, A.A note on diamond incidence in Wairagarh area, Garchiroli district, MaharashtraJournal of the Geological Society of India, Vol. 59, March pp. 265-268.India, MaharashtraConglomerates
DS200412-1733
2002
Gupta, A.Sashidharan, K., Mohanty, A.K., Gupta, A.A note on diamond incidence in Wairagarh area, Garchiroli district, Maharashtra.Journal of the Geological Society of India, Vol. 59, March pp. 265-268.India, MaharashtraConglomerates
DS1980-0150
1980
Gupta, A.K.Gupta, A.K., Yagi, K.Leucite Bearing Rocks of Manchuria, ChinaSpringer-verlag Publishing, 252P. PP. 86-89. CHINA.ChinaBlank
DS1980-0151
1980
Gupta, A.K.Gupta, A.K., Yagi, K.Petrology and Genesis of Leucite Bearing Rocks #2New York: Springer Verlag, Vol. 14, 252P.GlobalKimberley, Janlib
DS1980-0152
1980
Gupta, A.K.Gupta, A.K., Yagi, K., Thermier, H.Petrology and Genesis of Leucite Bearing Rocks #1Chemical Geology, Vol. 31, No. 1-2, PP. 161-163.GlobalLeucite, Genesis, History
DS1985-0253
1985
Gupta, A.K.Gupta, V.K., Gupta, A.K.Study of the system leucite akermanite SIO2 under oneatmosphericpressureIndian Journal of Earth Sciences, Vol. 12, No. 2, pp. 125-134IndiaLeucite
DS1986-0319
1986
Gupta, A.K.Gupta, A.K., Yagi, K., Lovering, J., Jaques, A.L.Geochemical and microprobe studies of diamond bearing ultramafic rocks from central and south IndiaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 27-29IndiaGeochemistry, Mineral chemistry
DS1990-1603
1990
Gupta, A.K.Yagi, K., Gupta, A.K., Chatterjee, V.P.The alkalic rocks from Amba Dunga, Deccan Plateau, IndiaInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 828-829IndiaCarbonatite, Ijolite
DS1991-0629
1991
Gupta, A.K.Gupta, A.K., Gaur, V.K., Zharikov, V.A., Chudenovshikh, L.T.Proceedings of the second Ind-Soviet Workshop on Experimental mineralogy and petrology. Short book reviewGovernment of India, Department of Science and Technology, 164p. do not have -perhaps can obtainIndiaExperimental petrology, Conference held October 1989
DS2000-0750
2000
Gupta, A.K.Pati, J.K., Arima, M., Gupta, A.K.Experimental study of the system diopside - albite - nepheline at 2 and 10Kbar and at P (total) 28 Kbar.Canadian Mineralogist, Vol. 38, pt. 5, Oct. pp. 1177-91.MantlePetrology - experimental, Nepheline
DS2002-0622
2002
Gupta, A.K.Gupta, A.K., Chattopadhyay, B., Fyfe, W.S., Powell, M.Experimental studies on three potassium rich ultramafic rocks from Damodar Valley, East India.Mineralogy and Petrology, Vol. 74, 2-4, pp. 343-60.India, eastAlkaline rocks
DS2003-0431
2003
Gupta, A.K.Fyfe, W.S., Gupta, A.K.Leucite rocks, igneous geochemistry, petrologyAne Books, New Delhi, India, 370p. GSC QE 462.A4 G86 2003GlobalBook - leucite rocks
DS2003-0657
2003
Gupta, A.K.Jia, Y., Kerrich, R., Gupta, A.K., Fyfe, W.S.15 N enriched Gondwana lamproites, eastern India: crustal N in the mantle sourceEarth and Planetary Science Letters, Vol. 215, 1-2, pp. 43-56.IndiaLamproites
DS200412-0594
2003
Gupta, A.K.Fyfe, W.S., Gupta, A.K.Leucite rocks, igneous geochemistry, petrology.ANE Books, New Delhi, India, 370p. GSC QE 462.A4 G86 2003TechnologyBook - leucite rocks
DS200412-0916
2003
Gupta, A.K.Jia, Y., Kerrich, R., Gupta, A.K., Fyfe, W.S.15 N enriched Gondwana lamproites, eastern India: crustal N in the mantle source.Earth and Planetary Science Letters, Vol. 215, 1-2, pp. 43-56.IndiaLamproite
DS200612-0953
2005
Gupta, A.K.Mukherje, A., Gupta, A.K., Babu, E.V.S.S.K.Majhgawan Diamondiferous pipe, Madhya Pradesh, India: is it a Group 1 kimberlite or Orangeite ( Group II kimberlite) or a lamproite?Geological Society of India, Bangalore November Meeting Group Discussion on Kimberlites and Related Rocks India, Abstract p. 113.India, Madhya Pradesh, Aravalli Bundelkhand CratonClassification
DS1990-0401
1990
Gupta, D.Dessai, A.G., Rock, N.M.S., Griffin, B.J., Gupta, D.Mineralogy and petrology of some xenolith bearing alkaline dykes associated with Deccan magmatism, south of Bombay IndiaEuropean Journal of Mineralogy, Vol. 2, No. 5, pp. 667-686IndiaAlkaline dykes, alkaline rocks, Xenoliths
DS200412-0684
2004
Gupta, G.Gokarn, S.G., Gupta, G., Rao, C.K.Geoelectric structure of the Dharwar Craton from magnetotelluric studies: Archean suture identified along the Chitradurga GadagGeophysical Journal International, Vol. 158, 2, pp. 712-728.IndiaGeophysics - magnetotellurics
DS200412-1621
2004
Gupta, G.Rao, C.K., Ogawa, Y., Gokarn, S.G., Gupta, G.Electromagnetic imaging of magma across the Narmada Son lineament, central India.Earth Planets and Space, Vol. 56, 2, pp. 229-238.. IngentaIndiaGeophysics - magnotellurics
DS201412-0302
2013
Gupta, G.Gokarn, S.G., Rao, C.K., Selvaraj, C., Gupta, G., Singh, B.P.Crustal evolution and tectonics of the Archean Bundelk hand craton, central India.Journal of the Geological Society of India, Vol. 82, No. 5, pp. 455-460.IndiaTectonics
DS1998-1208
1998
Gupta, H.K.Rao, V.V., Gupta, H.K., Tewari, H.C.A geotransect in the Central Indian Shield, across the Narmada Sonlineament and the Central Indian Suture.International Geology Review, Vol. 40, No. 11, Nov. pp. 1021-IndiaTectonics
DS1989-0558
1989
Gupta, J.C.Gupta, J.C., Jones, Kerr, Krentz, et al.Elecromagnetic sounding and crustal electrical conductivity in the region of the Wopmay Orogen.Canadian Journal of Earth Sciences, Vol. 26, pp. 2385-95.Northwest TerritoriesGeophysics - magnetics, Tectonics
DS201602-0191
2015
Gupta, K.Azeez, A., Veraswarmy, K.K., Gupta, K., Babu, A.K.The electrical resistivity structure of lithosphere across the Dharwar craton nucleus and Coorg block of South Indian Shield: evidence of collision and modified and preserved lithosphere.Journal of Geophysical Research, Vol. 120, 10, pp. 6698-6721.IndiaGeophysics - craton

Abstract: Magnetotelluric-derived two-dimensional lithospheric resistivity structure of the western Dharwar craton (WDC) and adjoining Coorg block indicates isolated low-resistivity zones in the crust and three striking upper mantle conductive features within the highly resistive Archean lithosphere. The crustal conductors in the WDC show good spatial correlation with the exposed supracrustal rocks conformable with the relic schist belt channels having conductive mineral grains. Conductive zones within the Coorg crust might be related to the relatively young (933?Ma) metamorphic processes in the area and/or possible fluids derived from the Cretaceous passage of Reunion plume in the proximity of Coorg area. A near-vertical conductive structure extending from the lower crust into the upper mantle coincides with the transition zone between Coorg and WDC. This is interpreted as the suture zone between the two tectonic blocks and provides evidence for the individuality of the two Archean terrains. An anomalous upper mantle conductive zone found beneath the craton nucleus may indicate a modified cratonic lithosphere. This could have been derived due to the collision between Coorg and WDC and possibly survived by the subsequent multiple episodes of melt and fluid infiltration processes experienced in the region. Thick (~190?km) and preserved lithosphere is mapped at the eastern segment of WDC. Resistive lithosphere of ~125?km thickness is imaged for the Coorg block.
DS1984-0630
1984
Gupta, L.N.Saxena, M.P., Gupta, L.N., Chaudhri, N.Carbonatite Dikes in Dhanota Dhancholi Hills, Narnaul, Haryana.Current Science., Vol. 53, No. 12, PP. 651-652.IndiaCarbonatite
DS1993-0594
1993
Gupta, M.L.Gupta, M.L.Is the Indian shield hotter than any other Gondwana shields?Earth and Planetary Science Letters, Vol. 115, No. 1-4, March pp. 275-286IndiaCraton, Heat flow
DS200412-0749
1991
Gupta, M.L.Gupta, M.L., Sundar, A., Sharma, S.R.Heat flow and heat generation in the Archean Dharwar Craton and implication for the southern Indian shield geotherm and lithosphTectonophysics, Vol. 194, pp. 107-122.IndiaGeothermometry
DS201412-0719
2013
Gupta, R.Rai, S.Borah, Kajaljyoti, Das, Gupta, R., Srivastava, S., Shalivahan, P., Sivaram, K., Kumar, K., Meena, S.The South India Precambrian crust and shallow lithospheric mantle: initial results from the India Deep Imaging Experiment ( INDEX).Journal of Earth System Science, Vol. 122, 6, pp. 1435-1453.IndiaDrilling
DS2003-0522
2003
Gupta, S.Gupta, S., Rai, S.S., Prakasam, K.S., Srinagesh, D., Basal, B.K., Chadha, R.K.The nature of the crust in southern India: implications for Precambrian crustal evolutionGeophysical Research Letters, Vol. 30, 8, 10.1029/2002GLO16770IndiaTectonics
DS2003-0523
2003
Gupta, S.Gupta, S., Rai, S.S., Prakasam, K.S., Sringesh, D., Chadha, R.K., Priestly, K.First evidence for anomalous thick crust beneath mid Archean western Dharwar cratonCurrent Science, Vol. 84, 9, pp. 1219-26.IndiaCraton
DS200412-0750
2003
Gupta, S.Gupta, S., Rai, S.S., Prakasam, K.S., Srinagesh, D., Basal, B.K., Chadha, R.K., Priestly, K., Gaur, V.K.The nature of the crust in southern India: implications for Precambrian crustal evolution.Geophysical Research Letters, Vol. 30, 8, 10.1029/2002 GLO16770IndiaTectonics
DS200412-0751
2003
Gupta, S.Gupta, S., Rai, S.S., Prakasam, K.S., Sringesh, D., Chadha, R.K., Priestly, K., Gaur, V.K.First evidence for anomalous thick crust beneath mid Archean western Dharwar craton.Current Science, Vol. 84, 9, pp. 1219-26.IndiaCraton
DS200512-0382
2005
Gupta, S.Gupta, S., Nanda, J., Mukerjee, S.K., Santra, M.Alkaline magmatism versus collision tectonics in the eastern Ghats Belt, India: constraints from structural studies in the Koraput Complex.Gondwana Research, Vol. 8, 3, pp. 403-420.India, AsiaAlkaline rocks, magmatism
DS200812-0573
2008
Gupta, S.Kiselev, S., Vinnik, L., Oreshin, S., Gupta, S., Rai, S.S., Singh, A., Kumar, Mohan.Lithosphere of the Dharwar craton by joint inversion of P and S receiver functions.Geophysical Journal International, In press ( available)IndiaGeophysics - seismics
DS202005-0730
2020
Gupta, S.Fareeduddin., Pant, N.C., Gupta, S., Chakraborty, P., Sensarma, S., Jain, A.K., Prasad, G.V.R., Srivastava, P., Rjan, S., Tiwari, V.M.The geodynamic evolution of the Indian subcontinent - an introduction.Episodes ( IUGS), Vol. 43, 1, pp. 1-18.Indiacarbonatite
DS202008-1412
2020
Gupta, S.Kumar, S., Gupta, S., Kanna, N., Sivaram, k.Crustal structures across the Deccan volcanic province and eastern Dharwar craton in south Indian shield using receiver function modelling.Physics of the Earth and Planetary Interiors, Vol. 306, 106543, 9p. PdfIndiageophysics -seismic

Abstract: The south Indian shield, primarily consisting of Archean cratons and Cretaceous-Tertiary Deccan Volcanic Province (DVP), has undergone several major tectonic episodes during its evolution. The Deccan volcanism at Cretaceous-Tertiary (~65 Ma) is the last major tectono-thermal event, which influenced a substantial part of the south Indian shield. To understand the influence of the Deccan volcanism on the evolution of the south Indian shield, we study the crustal seismic structure of the ~65 Ma Deccan Volcanic Province and the adjacent ~2.6 Ga Eastern Dharwar Craton (EDC), which forms the basement of the volcanic terrain. We calculate teleseismic receiver functions for 18 broadband seismic stations along a ~1000 km long seismological profile that cut across both the EDC and DVP. The analysis and modelling, using H-Vp/Vs stacking and generalized neighbourhood algorithm inversion of the receiver functions show distinct crustal structure (crustal thickness, average composition, shear wave velocity variation, nature of crust-mantle boundary, etc.) across the EDC and DVP. The results clearly indicate that the crustal structure is heterogeneous beneath the DVP compared to a relatively uniform structure below the EDC. Using results from this study along with earlier results, we infer that the present Eastern Dharwar Craton terrain is not affected by any tectono-thermal event for a long geological time, including the Deccan volcanism. Whereas, the present Deccan Volcanic Province is highly affected by the Reunion mantle plume-crust interaction.
DS202009-1627
2020
Gupta, S.Fareeduddin, Pant, N.C., Gupta, S., Chakraborty, P., Sensarma, S., Jain, A.K., Prasad, G.V.R., Srivastava, P., Rajan, S., Tiwari, V.M.The geodynamic evolution of the Indian subcontinent - an introduction.Episodes, Vol. 43, 1, pp. 8p.Indiacarbonatites
DS200412-1841
2004
Gupta, S.B.Singh, A.P., Mishra, D.C., Gupta, S.B., Rao, M.R.K.Crustal structure and domain tectonics of the Dharwar Craton ( India): insights from new gravity data.Journal of Asian Earth Sciences, Vol. 23, 1, March pp. 141-152.IndiaTectonics, geophysics - gravity, continental collision
DS1989-0559
1989
Gupta, S.K.Gupta, S.K., Rajakuma.., V., Grieveso..P.The influence of weathering on the reduction of ilmenite with carbonMetall. T-B., Vol. 20, No. 5, October pp. 735-745. AX896GlobalIlmenite -general, Weathering
DS1990-1368
1990
Gupta, S.K.Singh, B.P., Gupta, S.K., Dhawan, U., Lal, K.Characterization of synthetic diamonds by EPR and X-raydiffractiontechniquesJournal of Material Science, Vol. 25, No. 28, February pp. 1487-1490GlobalDiamond synthesis, EPR and X-ray diffraction
DS201212-0432
2012
Gupta, T.Mainkar, D., Gupta, T., Patel, S.C., Lehmann, B., Diwan, P., Kaminsky, F.V.Physical and infrared characteristics of diamonds from Bahradih kimberlite, Bastar Craton, India.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractIndiaDeposit - Behradih
DS201212-0580
2012
Gupta, T.Ravi, S., Sufija, M.V., Patel, S.C., Gupta, T., Sridhar, M., Kaminsky, F.V., Khachatryan, G.K., Netravali, S.V.Diamonds from the eastern Dharwar craton, India: their physical and infrared characteristics.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractIndiaDiamond morphology
DS201212-0616
2012
Gupta, T.Sahu, N., Gupta, T., Patel, S.C.,Khuntia, D.B.K., Thakur, S.S., Deas, S.K.Petrology of lamproites from the Nuapada lamproite field, Bastar Craton, India.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractIndiaDeposit - Nuapada
DS201312-0567
2013
Gupta, T.Mainkar, D., Gupta, T., Patel, S.C.Diamonds from the Behradih kimberlite pipe, Bastar craton, India: a reconnaissance study.Proceedings of the 10th. International Kimberlite Conference, Vol. 1, Special Issue of the Journal of the Geological Society of India,, Vol. 1, pp. 309-316.IndiaDeposit - Behradih
DS201312-0771
2013
Gupta, T.Sahu, N., Gupta, T., Patel, S.C.Petrology of lamproites from the Nuapada lamproite field, Bastar craton, India.Proceedings of the 10th. International Kimberlite Conference, Vol. 1, Special Issue of the Journal of the Geological Society of India,, Vol. 1, pp. 137-165.IndiaDeposit - Nuapada
DS201805-0949
2018
Gupta, T.Gupta, T.Carbon: the Black, the Gray and the Transparent.Springer Publication, Cost 129.00Technologycarbon

Abstract: All living things contain carbon in some form, as it is the primary component of macromolecules including proteins, lipids, nucleic acids (RNA and DNA), and carbohydrates. As a matter of fact, it is the backbone of all organic (chemistry) compounds forming different kinds of bonds. Carbon: The Black, the Gray and the Transparent is not a complete scientific history of the material, but a book that describes key discoveries about this old faithful element while encouraging broader perspectives and approaches to its research due to its vast applications. All allotropes of carbon are described in this book, along with their properties, uses, and methods of procurement or manufacturing. Black carbon is represented by coal, gray carbon is represented by graphite, and transparent carbon is represented by diamond.
DS1985-0253
1985
Gupta, V.K.Gupta, V.K., Gupta, A.K.Study of the system leucite akermanite SIO2 under oneatmosphericpressureIndian Journal of Earth Sciences, Vol. 12, No. 2, pp. 125-134IndiaLeucite
DS1990-0619
1990
Gupta, V.K.Gupta, V.K., Sutcliffe, R.H.Mafic ultramafic intrusives and their gravity field: Lac des Illes area, Ontario.Geological Society of America (GSA) Bulletin., Vol. 102, pp. 1471-83.Ontario, WawaAlkaline rocks, Geophysics - gravity
DS1991-0630
1991
Gupta, V.K.Gupta, V.K.Shaded image of total magnetic field of Ontario, northern sheetOntario Geological Survey Map, No. 2584OntarioGeophysics -magnetics
DS201802-0271
2017
Gupta, Y.M.Turneaure, S.J., Sharma, S.M., Volz, T.J., Winey, J.M., Gupta, Y.M.Transformation of shock compressed graphite to hexagonal diamond in nanoseconds.Science Advances, Vol. 3, 10, 6p.Technologythermodynamics

Abstract: The graphite-to-diamond transformation under shock compression has been of broad scientific interest since 1961. The formation of hexagonal diamond (HD) is of particular interest because it is expected to be harder than cubic diamond and due to its use in terrestrial sciences as a marker at meteorite impact sites. However, the formation of diamond having a fully hexagonal structure continues to be questioned and remains unresolved. Using real-time (nanosecond), in situ x-ray diffraction measurements, we show unequivocally that highly oriented pyrolytic graphite, shock-compressed along the c axis to 50 GPa, transforms to highly oriented elastically strained HD with the (100)HD plane parallel to the graphite basal plane. These findings contradict recent molecular dynamics simulation results for the shock-induced graphite-to-diamond transformation and provide a benchmark for future theoretical simulations. Additionally, our results show that an earlier report of HD forming only above 170 GPa for shocked pyrolytic graphite may lead to incorrect interpretations of meteorite impact events.
DS1986-0320
1986
Guptasarma, D.Guptasarma, D.The search for kimberlites; a recent discovery by NEGRISeminar on crustal dynamics, Indian Geophysical Union, Hyderabad India, P. 18. (abstract.)IndiaWajakaruru, Lattavaram, Andhra Pradesh
DS1986-0321
1986
Guptasarma, D.Guptasarma, D., Chetty, T.R.K., Murthy, D.S.N*n., Rao, A.V.R.Discovery of a new kimberlite pipe in Andhra Pradesh by streamsedimentsamplingJournal of Geological Society India, Vol. 27, No. 3, March pp. 313-316IndiaGeochemistry
DS1987-0262
1987
Guptasarma, D.Guptasarma, D., Chetty, T.R.K., Murthy, D.S.N., Ramana Rao, A.V.Case history of a kimberlite discovery, Wajrakarur area, Andhra IndiaExploration 87, technical abstract volume, held Toronto Sept. 2 27-Oct, p. 25. abstract onlyIndiaGeomorphology, Indicator minerals
DS1988-0277
1988
Guptasarma, D.Guptasarma, D., Chetty, T.R.K., Murthy, D.S.N., Ramana Rao, A.V.Case history of a kimberlite discovery, Wajrakaur area, A.P.,SouthIndiaExploration 87, Proceedings Volume, Ontario Geological Survey, Special Publishing No. 3, pp. 888-897IndiaGeophysics
DS1988-0278
1988
Guptill, S.C.Guptill, S.C., Cotter, D., Gibson, R., Liston, R., Tom, H., Trainor, T.A process for evaluating geographic information systemsUnited States Geological Survey (USGS) Open File, No. 88-0105, 55p. $ 21.25GlobalGIS, Technology Group
DS200812-0073
2008
Gupton, M.Bailey, B.L., Smith, L., Neuner, M., Gupton, M., Blowes, D.W., Smith, L., Sego, D.C., Gould, D.Diavik waste rock project: early stage geochemistry and microbiology of effluent from low sulfide content waste rock piles.Northwest Territories Geoscience Office, p. 11-12. abstractCanada, Northwest TerritoriesDeposit - Diavik
DS200812-1085
2008
Gupton, M.Smith, L., Neuner, M., Gupton, M., Bailey, B.L., Blowes, D., Smith, L., Sego, D.Diavik test piles project: design and construction of large scale research waste rock piles in the Canadian Arctic.Northwest Territories Geoscience Office, p. 57-58. abstractCanada, Northwest TerritoriesDeposit - Diavik
DS201312-0644
2013
Gupton, M.Neuner, M., Smith, L., Blowes, D.W., Sego, D.C., Smith, L.J.D., Fretz, N., Gupton, M.The Diavik waste rock project: water flow through mine waste rock in a permafrost terrain.Applied Geochemistry, Vol. 36, pp. 222-233.Canada, Northwest TerritoriesMining - Diavik
DS201312-0852
2013
Gupton, M.Smith, L.J.D., Moncur, M.C., Neuner, M., Gupton, M., Blowes, D.W., Smith, L., Sego, D.C.The Diavik waste rock project: particle size distribution and sulfur characteristics of low- sulfide waste rock.Applied Geochemistry, Vol. 36, pp. 187-199.Canada, Northwest TerritoriesMining - Diavik
DS201811-2576
2018
Gura, C.Gura, C., Kempton, P.D., Datta, S.Geochemistry in the critical zone; limestone shale and kimberlite weathering in the Flint Hills, Kansas. USA.Geological Society of America Annual Meeting, Vol. 50, 4, 1p. AbstractUnited States, Kansaskimberlite

Abstract: The Critical Zone is the realm where rocks meet life. This study examines the physicochemical interactions that occur when interbedded limestone-shale systems and kimberlitc eruptive materials weather to form soils. Fast weathering with extensive soil loss has been a major environmental concern in the Flint Hills. Knowledge of soil formation processes, rates of formation and loss and understanding how these processes differ in different systems are critical for managing soil as a resource. The kimberlites of Riley County, KS, are CO2-rich igneous rocks that are high in Mg and Fe; they are compositionally distinct from the Paleozoic limestones and shales found throughout the rest of the region. Bulk composition and mineralogy of the soils overlying these different bedrock types have been analyzed using X-Ray Fluorescence (XRF), X-Ray diffraction of <2mm soil fraction and <2µm soil clay fraction, bulk elemental extraction, and particle size analyses. Results show that the kimberlitic soils have higher concentrations of Fe, Mg, Ca, K and some trace elements (e.g. Ti, Ni, Cu). The weathering products differ mineralogically as well, e.g. lizardite is abundant in kimberlitic soils and absent from the limestone terrane. As a result, kimberlite-sourced soils have significantly different physical properties than the thin limestone-sourced soils surrounding them. Particle size analysis shows that the limestone-shale soils have a higher proportion of silt-sized particles whereas the kimberlitic soils have more clay (10.55% vs. 8.06%) and significantly more sand (36.12% vs. 14.83%). Mineralogy was determined for all <2mm fractions and for some <2µm soil clay fraction to understand the association and mobility of these major and trace elements in the respective soils. Interestingly some of the similarities between the kimberlite and limestone-shale soils suggests that loess/wind-blown sediment is making a significant contribution to the soil profile. Kimberlite-sourced and limestone-shale-sourced soils produce different weathering products and could potentially have agricultural significance in terms of ionic and nutrient mobility.
DS201610-1879
2016
Guralnik, B.King, G.E., Guralnik, B., Valla, P.G., Herman, F.Trapped charge thermochronometry and thermometry: a status review.Chemical Geology, in press available 15p.TechnologyThermometry

Abstract: Trapped-charge dating methods including luminescence and electron spin resonance dating have high potential as low temperature (< 100 °C) thermochronometers. Despite an early proof of concept almost 60 years ago, it is only in the past two decades that thermoluminescence (TL), electron-spin-resonance (ESR), and optically stimulated luminescence (OSL), have begun to gain momentum in geological thermochronometry and thermometry applications. Here we review the physics of trapped-charge dating, the studies that led to its development and its first applications for deriving palaeo-temperatures and/or continuous cooling histories. Analytical protocols, which enable the derivation of sample specific kinetic parameters over laboratory timescales, are also described. The key limitation of trapped-charge thermochronometry is signal saturation, which sets an upper limit of its application to < 1 Ma, thus restricting it to rapidly exhuming terrains (> 200 °C Ma? 1), or elevated-temperature underground settings (> 30 °C). Despite this limitation, trapped-charge thermochronometry comprises a diverse suite of versatile methods, and we explore potential future applications and research directions.
DS2001-1266
2001
Gurari, I.Wysession, M.E., Fischer, K.M., Gurari, I.Using MOMA broadband array ScS dat a to image smaller scale structures at the base of the mantle.Geophysical Research Letters, Vol. 28, No. 5, Mar. 1, pp. 867-70.MantleGeophysics - gravity, Structures
DS1990-0620
1990
Gurenko, A.A.Gurenko, A.A., Sobolev, A.V., Kononkova, N.N.New petrologic dat a on ugandites from the East African Rift, as revealed by study of magmatic inclusions in mineralsDoklady Academy of Science USSR, Earth Science Section, Vol. 305, No. 2, Sept. pp. 130-134UgandaPetrology, Ugandites
DS1990-0621
1990
Gurenko, A.A.Gurenko, A.A., Sobolev, A.V., Kononkova, N.N., Shcherbovskiy, Ye.Ya.Olivine from the ultrabasic and basic rocks of the East African rift system differentiated seriesGeochemistry International, Vol. 27, No. 10, pp. 117-123East AfricaPetrology, Ultrabasics -olivine -analyses
DS1990-0622
1990
Gurenko, A.A.Gurenko, A.A., Sobolev, A.V., Kononkova, N.N., Shcherbovsky, E.Y.Olivine of ultramafic and mafic rocks of the main differentiated seriesof the East African rift system (Russian)No. 3, March pp. 429-436, East AfricaGlobalPetrology
DS1993-0595
1993
Gurenko, A.A.Gurenko, A.A., Kononkova, N.N.Zoning of minerals as an indicator of the redox conditions of their crystallization ( as illustrated by high-potassium magma of the East AfricanRift)Doklady Academy of Sciences USSR, Earth Science Section, Vol. 318, No. 1-6, March 1992 Publishing date pp. 162-169Africa, East AfricaTectonics, Alkaline rocks
DS1994-0678
1994
Gurenko, A.A.Gurenko, A.A., Sobolev, A.V., Kononkova, N.N.The East African rift as indicated by magma inclusions in the mineralsDoklady Academy of Sciences Acad. Science USSR, Vol. 323, No. 2, June pp. 94-100.KenyaTectonics, Petrology
DS200612-0514
2006
Gurenko, A.A.Gurenko, A.A., Sobolev, A.V.Petrology and geochemistry of East African kamafugites: constraints from inclusions in minerals.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 220. abstract only.Africa, UgandaGeochemistry
DS200612-0623
2006
Gurenko, A.A.Ionov, D.A., Hofmann, A.W., Merlet, C., Gurenko, A.A., Hellebrand, E., Montagnac, G., Gillet, P., PrikhodkoDiscovery of whitlockite in mantle xenoliths: inferences for water and halogen poor fluid and trace element residence in the terrestrial upper mantle.Earth and Planetary Science Letters, Vol. 244, 1-2, Apr. 15, pp. 201-207.MantleXenolith - mineralogy
DS200712-0503
2007
Gurenko, A.A.Kamenetsky, V.S., Gurenko, A.A.Cryptic crustal contamination of MORB primitive melts recorded in olive hosted glass and mineral inclusions.Contributions to Mineralogy and Petrology, Vol. 153, 4, pp. 465-481..TechnologyMelting
DS200912-0273
2009
Gurenko, A.A.Gurenko, A.A., Sobolev, A.V., Hoernle, K.A., Hauff, F., Schincka, H-U.Enriched, HIMU type peridotite and depleted recycled pyroxenite in the Canary plume: a mixed up mantle.Earth and Planetary Science Letters, Vol. 277, 3-4, Jan. 30, pp. 514-524.Europe, Canary IslandsGeothermometry - subduction
DS201605-0903
2016
Gurenko, A.A.Sobolev, A.V., Asafov, E.V., Gurenko, A.A., Arndt, N.T., Batanova, V.G., Portnyagin, M.V., Garbe-Schonberg, D., Krasheninnikov, S.P.Komatites reveal a hydrous Archaen deep mantle reservoir.Nature, Vol. 531, Mar. 31, pp. 628-632.MantleMelting

Abstract: Archaean komatiites (ultramafic lavas) result from melting under extreme conditions of the Earth’s mantle. Their chemical compositions evoke very high eruption temperatures, up to 1,600 degrees Celsius, which suggests even higher temperatures in their mantle source1, 2. This message is clouded, however, by uncertainty about the water content in komatiite magmas. One school of thought holds that komatiites were essentially dry and originated in mantle plumes3, 4, 5, 6 while another argues that these magmas contained several per cent water, which drastically reduced their eruption temperature and links them to subduction processes7, 8, 9. Here we report measurements of the content of water and other volatile components, and of major and trace elements in melt inclusions in exceptionally magnesian olivine (up to 94.5?mole per cent forsterite). This information provides direct estimates of the composition and crystallization temperature of the parental melts of Archaean komatiites. We show that the parental melt for 2.7-billion-year-old komatiites from the Abitibi greenstone belt in Canada contained 30 per cent magnesium oxide and 0.6 per cent water by weight, and was depleted in highly incompatible elements. This melt began to crystallize at around 1,530 degrees Celsius at shallow depth and under reducing conditions, and it evolved via fractional crystallization of olivine, accompanied by minor crustal assimilation. As its major- and trace-element composition and low oxygen fugacities are inconsistent with a subduction setting, we propose that its high H2O/Ce ratio (over 6,000) resulted from entrainment into the komatiite source of hydrous material from the mantle transition zone10. These results confirm a plume origin for komatiites and high Archaean mantle temperatures, and evoke a hydrous reservoir in the deep mantle early in Earth’s history.
DS201709-1962
2017
Gurenko, A.A.Borisova, A.Y., Zagrtdenov, N.R., Toplis, M.J., Bohrson, W.A., Nedelec, A., Safonov, O.G., Pokrovski, G.S., Ceileneer, G., Melnik, O.E., Bychkov, A.Y., Gurenko, A.A., Shscheka, S., Terehin, A., Polukeev, V.M., Varlamov, D.A., Gouy, S., De Parseval, P.Making Earth's continental crust from serpentinite and basalt. Goldschmidt Conference, abstract 1p.Mantleperidotites

Abstract: How the Earth's continental crust was formed in the Hadean eon is a subject of considerable debates [1-4]. For example, shallow hydrous peridotites [2,5], in particular the Hadean Earth's serpentinites [6], are potentially important ingredients in the creation of the continental ptoto-crust, but the mechanisms of this formation remain elusive. In this work, experiments to explore serpentinite-basalt interaction under conditions of the Hadean Earth were conducted. Kinetic runs lasting 0.5 to 48 hours at 0.2 to 1.0 GPa and 1250 to 1300°C reveal dehydration of serpentinite and release of a Si-Al-Na-K-rich aqueous fluid. For the first time, generation of heterogeneous hydrous silicic melts (56 to 67 wt% SiO2) in response to the fluid-assisted fertilisation and the subsequent partial melting of the dehydrated serpentinite has been discovered. The melts produced at 0.2 GPa have compositions similar to those of the bulk continental crust [2,3]. These new findings imply that the Earth's sialic proto-crust may be generated via fluid-assisted melting of serpentinized peridotite at shallow depths (?7 km) that do not require plate subduction during the Hadean eon. Shallow serpentinite dehydration and melting may be the principal physico-chemical processes affecting the earliest lithosphere. Making Earth's continental crust from serpentinite and basalt.
DS201811-2577
2018
Gurenko, A.A.Gurenko, A.A., Sobolev, A.V.Can orthopyroxene be present in the source of Toro-Ankole, East African Rift, kamafugites?Journal of Petrology, Vol. 59, 8, pp. 1517-1550.Africa, Ugandakamafugites

Abstract: We have studied mineral-hosted melt, crystal and fluid inclusions from two ugandite, one mafurite and two katungite samples from the Toro-Ankole volcanic province in the East African Rift, which is the archetypal location for kamafugitic rocks. A main finding of our study is the presence of orthopyroxene as inclusions in an early generation of olivine from all three types of kamafugites, suggesting interaction of a carbonate-rich metasomatic agent with lithospheric peridotite mantle that may have caused almost complete dissolution of orthopyroxene. This process was preceded, accompanied or followed by the formation of phlogopite-clinopyroxene veins resulting from interaction of F-rich and low H2O/CO2 metasomatic fluids with the mantle rocks, which then became the source of the Toro-Ankole kamafugites. Pressure-temperature (P-T) estimates suggest that the parental kamafugitic melts last equilibrated with their source rocks at ?16?±?8?kbar and ?1160?±?130°C. This implies that they could have originated significantly below the solidus of dry, carbonated peridotite, but above the solidus of phlogopite-bearing clinopyroxenite. We conclude that the Toro-Ankole kamafugites originated by very low degrees of partial melting at moderately oxidized conditions (?FMQ = +2•2?±?0•4?atm log units, where FMQ is fayalite-magnetite-quartz buffer) under a high geothermal gradient of 60-80?mW?m?2, in response to lithospheric extension and probable association with an adjacent mantle plume. We estimate that differentiation of parental ugandite, mafurite and katungite magmas could have occurred at depths <12?km in the T range 1150-850°C. Laboratory-heated, homogenized melt inclusions trapped by a second generation of olivine and clinopyroxene are characterized by remarkable silica-undersaturation, compared with mid-ocean ridge basalt and ocean island basalt magmas, with high concentrations of alkalis, Ti, Ba, Sr and Zr, but varying to very low concentrations of Al and Ca. Such alkali-rich, strongly evolved melts might have resulted from extreme (>95%) fractional crystallization of the parental magmas, assuming their chemical compositions to be similar to those of the respective lavas. However, this estimate is about three times higher than the modal amount of phenocrysts in the lavas that could be reinforced by the presence of excess cognate crystals and/or xenocrysts in the lavas. Strong oxidation from FMQ?+?2 to FMQ?+?4 to +?5•2?atm log units of the evolved mafuritic magmas at ?900-1000°C has occurred during the final stage of magma evolution at very shallow crustal depths or possibly directly in the lava flow.
DS201910-2306
2019
Gurer, D.Van Hinsbergen, D.J.J., Torsvik, T.H., Schmid, S.M., Matenco, L.C., Maffione, M., Vissers, R.L.M., Gurer, D., Spakman, W.Orogenic architecture of the Mediterranean region and kinematic reconstruction of its tectonic evolution since the Triassic. AtriaGondwana Research, in press available 427p.Europecraton

Abstract: The basins and orogens of the Mediterranean region ultimately result from the opening of oceans during the early break-up of Pangea since the Triassic, and their subsequent destruction by subduction accommodating convergence between the African and Eurasian Plates since the Jurassic. The region has been the cradle for the development of geodynamic concepts that link crustal evolution to continental break-up, oceanic and continental subduction, and mantle dynamics in general. The development of such concepts requires a first-order understanding of the kinematic evolution of the region for which a multitude of reconstructions have previously been proposed. In this paper, we use advances made in kinematic restoration software in the last decade with a systematic reconstruction protocol for developing a more quantitative restoration of the Mediterranean region for the last 240 million years. This restoration is constructed for the first time with the GPlates plate reconstruction software and uses a systematic reconstruction protocol that limits input data to marine magnetic anomaly reconstructions of ocean basins, structural geological constraints quantifying timing, direction, and magnitude of tectonic motion, and tests and iterations against paleomagnetic data. This approach leads to a reconstruction that is reproducible, and updatable with future constraints. We first review constraints on the opening history of the Atlantic (and Red Sea) oceans and the Bay of Biscay. We then provide a comprehensive overview of the architecture of the Mediterranean orogens, from the Pyrenees and Betic-Rif orogen in the west to the Caucasus in the east and identify structural geological constraints on tectonic motions. We subsequently analyze a newly constructed database of some 2300 published paleomagnetic sites from the Mediterranean region and test the reconstruction against these constraints. We provide the reconstruction in the form of 12 maps being snapshots from 240 to 0 Ma, outline the main features in each time-slice, and identify differences from previous reconstructions, which are discussed in the final section.
DS1991-0917
1991
Gurevich, A.V.Kononova, V.A., Sveshnikova, Ye.V., Drynkin, V.I., Gurevich, A.V.Potassic and potassic sodic series of volcanics in the Cenozoic ofYugoslaviaInternational Geology Review, Vol. 33, No. 8, August pp. 793-806YugoslaviaNephelinite, Shoshonite
DS1991-0918
1991
Gurevich, A.V.Kononova, V.A., Sveshnikova, Ye.V., Drynkin, V.I., Gurevich, A.V.Potassic and potassic-sodic series of volcanics in the Cenozoic ofYugoslaviaInternational Geology Review, Vol. 33, No. 8, August pp. 793-806YugoslaviaPotassic rocks, Cenozoic
DS1998-0289
1998
Gurevitch, A.B.Czamanske, G.K., Gurevitch, A.B., Simonov, O.Demise of the Siberian plume: paleogeographic and paleotectonic reconstruction from the Prevolcanic...International Geology Review, Vol. 40, No. 2, Feb. pp. 95-115Russia, SiberiaVolcanics, Tectonics - plumes
DS1860-0988
1897
Gurich, G.Gurich, G.Zur Theorie der Afrikanischen DiamantlagerstattenZeitschr. F. Prakt. Geol., Vol. 5, PP. 145-148. ALSO: PHIL. SOC. STH. AFR. Transactions, Vol.Africa, South Africa, Cape ProvinceGeology, Genesis
DS2003-0713
2003
Guriev, G.A.Khudoley, A.K., Guriev, G.A.Influence of syn-sedimentary faults on orogenesis structure: examples from theTectonophysics, Vol. 365, 1-4, pp.23-43.RussiaOrogenesis
DS200412-0999
2003
Guriev, G.A.Khudoley, A.K., Guriev, G.A.Influence of syn-sedimentary faults on orogenesis structure: examples from the Neoproterozoic Mesozoic east Siberian passive marTectonophysics, Vol. 365, 1-4, pp.23-43.RussiaOrogenesis
DS1986-0889
1986
GurkinaZaitseva, GurkinaCause of color of grey and brown, probably due to crystal defects.(Russian)Mineral. Zhurn., (Russian), Vol. 8, No. 3, pp. 48-52Russiaref. Fleischer United States Geological Survey (USGS) OF 88-689.Mineralogical refs. 198, Diamond morphology
DS1975-0516
1977
Gurkina, G.A.Godlevskii, M.N., Gurkina, G.A.Octahedron Cube Morphogenetic Series of Diamond CrystalsZapiski Veses. Mineral. Obshch., No. 6, PP. 641-650.RussiaCrystallography
DS1975-1042
1979
Gurkina, G.A.Gurkina, G.A., Ivanovskaya, I.N., Kaminskiy, F.V., Galimov, E.M.The Distribution of Carbon Isotopes in Diamond Crystals.(russian)Geochemistry International (Geokhimiya)(Russian), Vol. 1979, No. 12, pp. 1897-1905RussiaBlank
DS1980-0153
1980
Gurkina, G.A.Gurkina, G.A.Research on the Internal Morphology of Spherical Diamonds By the Methods of X-ray Topography and Birefringence.Tsnigri, No. 153, PP. 43-51.RussiaBlank
DS1985-0067
1985
Gurkina, G.A.Blinova, G.K., Gurkina, G.A., Frolova, L.N.A Study of Polycrystalline Aggregates of Diamond With lonsdaleite Using the Methods of X-ray Radiography And infrared Spectroscopy.(russian)Mineral. Sbornik., (Russian), Vol. 39, No. 2, pp. 18-21RussiaBlank
DS1986-0890
1986
Gurkina, G.A.Zaitseva, T.M., Gurkina, G.A.Nature of grayish smoky and brownish coloration of diamondcrystals.(Russian)Mineral. Zhurn., (Russian), Vol. 8, No. 3, pp. 48-52RussiaDiamond morphology
DS1986-0893
1986
Gurkina, G.A.Zaytseva, T.M., Gurkina, G.A.The nature of grey smoky and brown colour of diamond crystals.(Russian)Mineral. Zhurn., (Russian), Vol. 8, No. 3, pp. 48-52RussiaDiamond, Morphology
DS1988-0064
1988
Gurkina, G.A.Blinova, G.K., Gurkina, G.A., Simakov, S.K.Some chemical properties of the medium from which natural diamondscrystallizeDoklady Academy of Science USSR, Earth Science Section, Vol. 301, No. 4, July-Aug, pp. 207-209RussiaDiamond morphology, Crystallography
DS200512-1264
2004
Gurkina, G.A.Zinchuk, N.N., Koptil, V.I., Gurkina, G.A., Kharrasov, M.K.Study of optically active centres in diamonds from Uralian placers: an attempt to locate their primary deposits.Russian Geology and Geophysics, Vol. 45, 2, pp. 226-234.Russia, UralsDiamond morphology, alluvials
DS1998-1153
1998
Gurmendi, A.Perry, A., Gurmendi, A.Reasonable environmental regulations and controls in Latin America for sustainable economic developmentSociety for Mining, Metallurgy and Exploration (SME) Preprint, No. 98-15Latin AmericaLegal, Environmental regulations
DS1999-0277
1999
Gurmendi, A.C.Gurmendi, A.C., Barboza, F.L., Thorman, C.H.The mineral economy of BrasilUnited States Geological Survey (USGS) CD RoM., DDS-0053, 1 cd $ 32.00BrazilEconomics, legal, Geology, deposits
DS201212-0273
2012
Gurnell, A.M.Gurnell, A.M., Sertolki, W., Cornenblit, D.Changing river channels: the role of hydrological processes, plants and pioneer fluvial landforms in humid temperate, mixed load, gravel bed rivers.Earth Science Reviews, Vol. 111, 1-2, pp. 129-141.TechnologyGeomorpholgy - not specific to diamonds
DS1995-1966
1995
GurneyVan Heerden, L.A., Taylor, W.R., Kirkley, Gurney, BulanovaComparison of physical spectroscopic and stable isotope characteristics of Roberts Victor diamonds.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 231-232.South AfricaCathodluminescence, Deposit -Roberts Victor
DS1997-0445
1997
GurneyGriffin, W.L., Moore, R.O., Ryan, Gurney, WinGeochemistry of magnesian ilmenite megacrysts from Southern african kimberlites #2Russian Geology and Geophysics, Vol. 38, No. 2, pp. 421-443.South Africa, Botswana, Namibia, LesothoGeochemistry, Megacrysts
DS1997-0617
1997
GurneyKopylova, M.G., Rickard, P.S., Kleyenstueber, Taylor, Gurney, DanielsFirst occurrence of strontian K-chromium-loparite and chromium- chevkinite indiamonds.Russian Geology and Geophysics, Vol. 38, No. 2, pp. 405-420.ZimbabweDiamond inclusions, Deposit - River Ranch
DS1998-0250
1998
GurneyChinn, I.L., McCallum, M.E., Harris, Milledge, GurneyCO2 bearing diamonds in eclogite xenoliths from the Sloan 2 kimberlite, Colorado.7th International Kimberlite Conference Abstract, p. 155.Colorado, WyomingEclogite xenoliths, Deposit - Sloan 2
DS2001-1301
2001
GurneyZhang, H.F., Menzies, M.A., Mattey, Hinton, GurneyPetrology, mineralogy and geochemistry of oxide minerals in polymict xenoliths from Bultfontein...Contributions to Mineralogy and Petrology, Vol. 141, No. 3, June, pp. 367-79.South AfricaGeochronology - low bulk rock oxygen ratios, Deposit - Bultfontein
DS1995-0684
1995
Gurney, J.Griffin, W.L., Moore, R.O., Ryan, C.G., Gurney, J., Win, T.Geochemistry of magnesian ilmenite megacrysts from southern African kimberlites #1Proceedings of the Sixth International Kimberlite Conference Extended, p. 196-7.South AfricaGeochemistry -ilmenite, Deposit -Kimberley, Uintjiesberg
DS1995-0833
1995
Gurney, J.Hutchinson, M.T., Harte, B., Moore, R.O., Gurney, J.A rare earth elements (REE) study of megacrysts from the Monastery diatremeTerra Nova, Abstract Vol., p. 334.South AfricaGeochronology, Deposit -Monastery
DS1995-2073
1995
Gurney, J.Woodborne, M.W., De Decker, R.H., Hollick, P.C., Gurney, J.New information on wave cut terraces and the importance in relation To diamond deposits on west coast South AfricaExploration and Mining Geology, Vol. 4, No. 1, p. 91.South AfricaMarine mining, Terraces
DS1996-0643
1996
Gurney, J.Hollick, P., Gurney, J.Namaqualand and Namibian off shore diamond distributionProspectors and Developers Association of Canada (PDAC) Short Course, pp. 219-238NamibiaGeostatistics, statistics, diamond, Short course -Exploration technology
DS1996-0644
1996
Gurney, J.Hollick, P., Gurney, J.Namaqualand and Namibian off shore diamond distribution, a wave refractioncontrol.Prospectors and Developers Association of Canada (PDAC) Short Course, 96, pp. 219-238.Namibia, South AfricaAlluvials, Marine, Mining techniques
DS2003-0512
2003
Gurney, J.Grutter, H., Gurney, J., Nowicki, T., Moore, R.Early stage assessment of kimberlites using indicator minerals, petrography andQuebec Exploration Conference, Nov. 25-27, 1p. abstractGlobalMicrodiamonds
DS200412-0733
2003
Gurney, J.Grutter, H., Gurney, J., Nowicki, T., Moore, R.Early stage assessment of kimberlites using indicator minerals, petrography and microdiamonds.Quebec Exploration Conference, Nov. 25-27, 1p. abstractTechnologyMicrodiamonds
DS200612-0627
2006
Gurney, J.Ivanic, T., Harte, B., Gurney, J.Multiple events affecting highly chromian, garnet rich peridotite xenoliths from South Africam kimberlites. Newlands, Bobbejaan.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p. 137.Africa, South AfricaGeothermometry
DS200712-0396
2007
Gurney, J.Gurney, J., Nowicki, T., Moore, R., Baumgartner, M.Recent advances in understanding diamond formation events, their relevance to exploration and some remaining questions.Diamonds in Kimberley Symposium & Trade Show, Bristow and De Wit held August 23-24, Kimberley, South Africa, GSSA Diamond Workshop CD slides 19Africa, southern AfricaGeochemistry, geochronology, evolution , geothermometry
DS200712-0669
2007
Gurney, J.Maier, W.D., McDonald, I., Peltonen, P., Barnes, S-J., Gurney, J., Hatton, C.Platinum group elements in mantle xenoliths from the Kaapvaal Craton.Plates, Plumes, and Paradigms, 1p. abstract p. A614.Africa, South Africa, Botswana, LesothoKimberley, Jagersfontein, Lethlakane, Finsch, Venetia
DS200812-0225
2008
Gurney, J.Coe, N., Le Roex, A., Gurney, J., Pearson, D.G., Nowell, G.Petrogenesis of the Swartruggens and Star Group II kimberlite dyke swarms, South Africa: constraints from whole rock geochemistry.Contributions to Mineralogy and Petrology, Vol. 156, pp. 627-652.Africa, South AfricaKaapvaal Craton, petrogenesis
DS200812-0226
2008
Gurney, J.Coe, N., Roex, A., Gurney, J., Pearson, D.G., Nowell, G.Petrogenesis of the Swartuggens and Star Group II kimberlite dyke swarms, South Africa: constraints from whole rock geochemistry.Contributions to Mineralogy and Petrology, Vol. 156, 5, pp. 627-652.Africa, South AfricaDeposit - Swartruggens and Star
DS200812-0639
2008
Gurney, J.Le Roex, A., Coe, N., Gurney, J., Pearson, D.G., Nowell, G.Petrogenesis of Group II kimberlites: a case study from southern Africa.9IKC.com, 3p. extended abstractAfrica, South Africa, BotswanaDeposit - Swartruggens, Star
DS200812-0805
2008
Gurney, J.Nowicki, T., Helman, C., Gurney, J., Van Coller, B., Galloway, M., Smith, C., Mukodzani, B.Optimizing kimberlite evaluation programs by integrating geological, mineralogical and geophysical data.GSSA-SEG Meeting Held July, Johannesburg, 19 Power point slidesTechnologyEvaluation
DS200812-0806
2008
Gurney, J.Nowicki, T., Hetman, C.J., Gurney, J., Van Collar, B., Galloway, M., Mukodzani, B.Optimizing kimberlite evaluation programs by integrating geological, mineralogical and geophysical data.Northwest Territories Geoscience Office, p. 46-47. abstractTechnologyBrief overview - evaluation
DS200912-0240
2009
Gurney, J.Galloway, M., Nowicki, T., Van Coller, B., Mukodzani, B., Siemens, K., Hetman, C., Webb, K., Gurney, J.Constraining kimberlite geology through integration of geophysical, geological and geochemical methods: a case study of the Mothae kimberlite, northern Lesotho.Lithos, In press - available 47p.Africa, LesothoDeposit - Mothae
DS201607-1381
2016
Gurney, J.Tappe, S., Griffin, W., Janney, P., Arndt, N., Gurney, J.The dynamic Earth and its kimberlite, cratonic mantle and diamond record through time.IGC 35th., Session A Dynamic Earth 1p. AbstractMantleKimberlite
DS201804-0714
2018
Gurney, J.Korolev, N.M., Kopylova, M., Bussweiller, Y., Pearson, D.G., Gurney, J., Davidson, J.The uniquely high temperature character of Culli nan diamonds: a signature of the Bushveld mantle plume?Lithos, Vol. 304, pp. 362-373.Africa, South Africadeposit - Cullinan

Abstract: The mantle beneath the Cullinan kimberlite (formerly known as "Premier") is a unique occurrence of diamondiferous cratonic mantle where diamonds were generated contemporaneously and shortly following a mantle upwelling that led to the formation of a Large Igneous Province that produced the world's largest igneous intrusion - the 2056?Ma Bushveld Igneous Complex (BIC). We studied 332 diamond inclusions from 202 Cullinan diamonds to investigate mantle thermal effects imposed by the formation of the BIC. The overwhelming majority of diamonds come from three parageneses: (1) lithospheric eclogitic (69%), (2) lithospheric peridotitic (21%), and (3) sublithospheric mafic (9%). The lithospheric eclogitic paragenesis is represented by clinopyroxene, garnet, coesite and kyanite. Main minerals of the lithospheric peridotitic paragenesis are forsterite, enstatite, Cr-pyrope, Cr-augite and spinel; the sublithospheric mafic association includes majorite, CaSiO3 phases and omphacite. Diamond formation conditions were calculated using an Al-in-olivine thermometer, a garnet-clinopyroxene thermometer, as well as majorite and Raman barometers. The Cullinan diamonds may be unique on the global stage in recording a cold geotherm of 40?mW/m2 in cratonic lithosphere that was in contact with underlying convecting mantle at temperatures of 1450-1550?°C. The studied Cullinan diamonds contain a high proportion of inclusions equilibrated at temperatures exceeding the ambient 1327?°C adiabat, i.e. 54% of eclogitic diamonds and 41% of peridotitic diamonds. By contrast, ? 1% of peridotitic diamond inclusions globally yield equally high temperatures. We propose that the Cullinan diamond inclusions recorded transient, slow-dissipating thermal perturbations associated with the plume-related formation of the ~2?Ga Bushveld igneous province. The presence of inclusions in diamond from the mantle transition zone at 300-650?km supports this view. Cullinan xenoliths indicative of the thermal state of the cratonic lithosphere at ~1.2?Ga are equilibrated at the relatively low temperatures, not exceeding adiabatic. The ability of diamonds to record super-adiabatic temperatures may relate to their entrainment from the deeper, hotter parts of the upper mantle un-sampled by the kimberlite in the form of xenoliths or their equilibration in a younger lithosphere after a decay of the thermal disturbance.
DS1991-1185
1991
Gurney, J.JMoore, R.O., Gurney, J.J, Griffin, W.L., Shimizu, N.Ultra high pressure garnet inclusions in Monastery diamonds -trace element abundance patterns and conditions of originEur. Journal of Mineralogy, Vol. 3, No. 2, pp. 213-230South AfricaGeochemistry, Monastery -inclusions -garnet
DS1960-0675
1966
Gurney, J.J.Gurney, J.J., Berg, G.W., Ahrens, L.H.Observations on Caesium Enrichment and the Potassium Rubidium Caesium Relationship in Eclogites from the Roberts Victormine.Nature., Vol. 210, PP. 1025-1027.South AfricaGeochronology, Mineralogy
DS1960-0676
1966
Gurney, J.J.Gurney, J.J., Erlank, A.J.D.c. Arc Spectrographic Technique for the Determination of Trace Amounts Lithium, Rubidium and Cesium in Silicate Rocks.Anal. Chem., Vol. 38, PP. 1836-1839.South AfricaSampling, Spectrometry
DS1960-0958
1968
Gurney, J.J.Gurney, J.J.The Geochemical Distribution of Some Elements in Ultrabasicrocks.Ph. D. Thesis, University Cape Town., South AfricaUltramafic Rocks
DS1960-1119
1969
Gurney, J.J.Gurney, J.J., Berg, G.W.Potassium, Rubidium and Caesium in South African Kimberlites and Their Xenoliths in Upper Mantle Project.Geological Society of South Africa SPECIAL Publishing, No. 2, PP. 417-427.South AfricaPetrography
DS1960-1120
1969
Gurney, J.J.Gurney, J.J., Siebert, J.C., Whitfield, G.G.A Diamondiferous Eclogite from the Roberts Victor Mine in Upper Mantle Project.Geological Society of South Africa SPECIAL Publishing, No. 2, PP. 351-357.South AfricaPetrography
DS1960-1200
1969
Gurney, J.J.Rickwood, P.C., Gurney, J.J., White-Cooper, D.R.R.The Nature and Occurrences of Eclogite Xenoliths in the Kimberlites of Southern Africa.Geological Survey of South Africa SPECIAL Publishing, No. 2, PP. 371-393.South AfricaGeology, Petrography
DS1970-0301
1971
Gurney, J.J.Gurney, J.J., Mathias, M., Siebert, C., Moseley, G.Kyanite Eclogites from the Rietfontein Kimberlite Pipe, Mier Coloured Reserve, Gordonia, Cape Province, South Africa.Contributions to Mineralogy and Petrology, Vol. 30, No. 1, PP. 46-52.South AfricaMineralogy
DS1970-0520
1972
Gurney, J.J.Gurney, J.J.Plumbing the Secrets If the Earth's MantleInternational DIAMOND ANNUAL, Vol. 2, PP. 42-48.GlobalKimberlite, Genesis
DS1970-0525
1972
Gurney, J.J.Hawthorne, J.B., Harris, J.W., Gurney, J.J., Rickard, R.Inclusions in Diamonds from Southern AfricaPreprint, 21p.South AfricaDiamond Inclusions, Deposit - Premier, Finsch, Koffiefontein
DS1970-0653
1973
Gurney, J.J.Cox, K.G., Gurney, J.J., Harte, B.Xenoliths from the Matsoku PipeMaseru: Lesotho Nat. Dev. Corp. Lesotho Kimberlites Editor N, PP. 76-100.LesothoGeology, Petrography, Texture, Buckmann, Mineral Chemistry
DS1970-0683
1973
Gurney, J.J.Fesq, H.W., Kable, E.J.D., Gurney, J.J.Some Aspects of the Geochemistry of Kimberlites from the Premier Mine, Transvaal, South Africa.1st International Kimberlite Conference, EXTENDED ABSTRACT VOLUME, PP. 115-118.South AfricaGeochemistry
DS1970-0699
1973
Gurney, J.J.Gurney, J.J., Ahrens, L.H.The Zinc Content of Some Ultramafic and Basic RocksGeological Society of South Africa Transactions, Vol. 76, No. 3, PP. 301-307.South AfricaMineralogy
DS1970-0700
1973
Gurney, J.J.Gurney, J.J., Ebrahim, S.Chemical Composition of Lesotho KimberlitesMaseru: Lesotho Nat. Dev. Corp. Lesotho Kimberlites Editor N, PP. 280-284.Lesotho, South Africa, RussiaGeochemistry
DS1970-0701
1973
Gurney, J.J.Gurney, J.J., Fesq, H.W., Kable, E.J.D.Clinopyroxene Ilmenite Intergrowths from Kimberlite a Re-appraisal.Maseru: Lesotho Nat. Dev. Corp. Lesotho Kimberlites, Editor, PP. 238-253.Lesotho, United States, Kentucky, Appalachia, KansasBlank
DS1970-0702
1973
Gurney, J.J.Gurney, J.J., Harte, B., Cox, K.G.The Composition of the Mantle Xenoliths in the Matsoku Pipe1st International Kimberlite Conference, EXTENDED ABSTRACT VOLUME PP. 139-142.LesothoMineralogy
DS1970-0703
1973
Gurney, J.J.Gurney, J.J., Hobbs, J.B.M.Potassium, Thorium and Uranium in Some Kimberlites from South Africa.1st International Kimberlite Conference, EXTENDED ABSTRACT VOLUME, PP. 143-146.South AfricaMineralogy
DS1970-0704
1973
Gurney, J.J.Gurney, J.J., Switzer, G.S.The Discovery of Garnets Closely Related to Diamonds in The finsch Pipe, South Africa.Contributions to Mineralogy and Petrology, Vol. 39, No. 2, PP. 103-116.South AfricaMineralogy
DS1970-0709
1973
Gurney, J.J.Harte, B., Cox, K.G., Gurney, J.J.Petrography and Geological History of Upper Mantle Xenoliths from the Matsoku Kimberlite Pipe #11st International Kimberlite Conference, EXTENDED ABSTRACT VOLUME, PP. 155-158.LesothoPetrography
DS1970-0710
1973
Gurney, J.J.Harte, B., Gurney, J.J.Evolution of Clinopyroxene and Garnet in an Eclogite Nodule from the Roberts Victor Kimberlite Pipe.1st International Kimberlite Conference, EXTENDED ABSTRACT VOLUME, PP. 159-162.South AfricaMineralogy, Xenoliths
DS1970-0731
1973
Gurney, J.J.Kable, E.J.D., Fesq, H.W., Gurney, J.J.The Significance of Minor Element Relationships of Some Minor and Trace Elements in South African Kimberlites.1st International Kimberlite Conference, EXTENDED ABSTRACT VOLUME, PP. 185-188.South AfricaMineralogy
DS1970-0919
1974
Gurney, J.J.Gurney, J.J.The Origin of Kimberlite - Modern ConceptsGeological Society of South Africa Transactions, Vol. 77, No. 3, PP. 353-361.Lesotho, South AfricaGenesis
DS1975-0053
1975
Gurney, J.J.Clement, C.R., Gurney, J.J., Skinner, E.M.W.Monticellite and Abundant Groundmass Component of Some Kimberlites.Kimberlite Symposium I, Held Cambridge., EXTENDED ABSTRACT VOLUME.South AfricaGenesis, Petrography
DS1975-0059
1975
Gurney, J.J.Dawson, J.B., Gurney, J.J., Lawless, P.J.Paleothermal Gradients Derived from Xenoliths in KimberliteNature., Vol. 257, No. 5524, PP. 299-300.South AfricaGeothermometry
DS1975-0079
1975
Gurney, J.J.Fesq, H.W., Kable, E.J.D., Gurney, J.J.Aspects of the Geochemistry of Kimberlites from the Premier mine and Other Selected South African Occurrences with Particular Reference to the Rare Earth Elements.Physics and Chemistry of the Earth., Vol. 9, PP. 687-707.South AfricaMineral Chemistry, Rare Earth Elements (ree)
DS1975-0093
1975
Gurney, J.J.Gurney, J.J., Harte, B., Cox, K.G.The Composition of Mantle Xenoliths in the Matsoku PipePhysics and Chemistry of the Earth., Vol. 9, PP. 507-524.LesothoPetrography, Mineral Chemistry
DS1975-0097
1975
Gurney, J.J.Harte, B., Cox, K.G., Gurney, J.J.Petrography and Geological History of Upper Mantle Xenoliths from the Matsoku Kimberlite Pipe #2Physics and Chemistry of the Earth., Vol. 9, PP. 477-506.LesothoPetrography, Geology
DS1975-0098
1975
Gurney, J.J.Harte, B., Gurney, J.J.Ore Mineral and Phlogopite Mineralization Within Ultramafic nodules from the Matsoku Kimberlite Pipe.Carnegie Institute Yearbook, FOR 1974, PP. 528-536.LesothoPetrography
DS1975-0099
1975
Gurney, J.J.Harte, B., Gurney, J.J.Evolution of Clinopyroxene and Garnet in Eclogite Nodule From the Roberts Victor Kimberlite Pipe.Physics and Chemistry of the Earth., Vol. 9, PP. 367-387.South AfricaMineral Chemistry, Petrography
DS1975-0115
1975
Gurney, J.J.Kable, E.J.D., Fesq, H.W., Gurney, J.J.The Significance of the Inter-element Relationships of Some minor and Trace Elements in South African Kimberlites.Physics and Chemistry of the Earth., Vol. 9, PP. 709-734.South AfricaRare Earth Elements (ree), Petrography
DS1975-0148
1975
Gurney, J.J.Newton, A.R., Gurney, J.J.Discussion of a Plate Tectonic Origin for Diamond Bearing Kimberlites.Earth and Planetary Science Letters, Vol. 27, PP. 356-358.South AfricaTectonics, Kimberlite Genesis
DS1975-0278
1976
Gurney, J.J.Fesq, H.W., Kable, E.J.D., Gurney, J.J.The Geochemistry of Some Selected South African Kimberlites and Associated Heavy Minerals.Johannesburg: Nat. Institute Met. Report, No. 1703, 33P.South AfricaMineral Chemistry, Kimberley
DS1975-0518
1977
Gurney, J.J.Gurney, J.J.Formation of the DiamondIndiaqua., No. 16, PP. 19-23.GlobalDiamond, Morphology, Origin
DS1975-0519
1977
Gurney, J.J.Gurney, J.J.What Is Kimberlite?Indiaqua., No. 15, PP. 7-12.GlobalGenesis, Origin
DS1975-0523
1977
Gurney, J.J.Hatton, C.J., Gurney, J.J.Kyanite Eclogites from the Roberts Victor MineProceedings of Second International Kimberlite Conference, EXTENDED ABSTRACT VOLUME.South AfricaPetrography, Mineralogy
DS1975-0524
1977
Gurney, J.J.Hatton, C.J., Gurney, J.J.Igneous Fractionation Trends in Roberts Victor EclogitesProceedings of Second International Kimberlite Conference, EXTENDED ABSTRACT VOLUME.South AfricaPetrology
DS1975-0825
1978
Gurney, J.J.Nixon, P.H., Chapman, N.A., Gurney, J.J.Pyrope Spinel (alkremite) Xenoliths Form KimberlitesContirb. Min. Petrol., Vol. 65, No. 3, PP. 341-346.GlobalMineral Chemistry
DS1975-1043
1979
Gurney, J.J.Gurney, J.J.Diamond Recovery Operations Along the Namaqualand CoastIndiaqua., No. 20, 1979/1, PP. 9-14.South AfricaDiamond Mining Recovery, Littoral Placers
DS1975-1044
1979
Gurney, J.J.Gurney, J.J., Harris, J.W., Rickard, R.S.Silicate and Oxide Inclusions in Diamond from the Finsch Kimberlite Pipe.Proceedings of Second International Kimberlite Conference, Proceedings Vol. 1, PP. 1-15.South AfricaMineralogy
DS1975-1045
1979
Gurney, J.J.Gurney, J.J., Jakob, W.K.O., Dawson, J.B.Metacrysts from the Monastery Kimberlite PipeProceedings of Second International Kimberlite Conference, Proceedings Vol. 2, PP. 227-243.South AfricaPetrography
DS1975-1061
1979
Gurney, J.J.Hatton, C.J., Gurney, J.J.A Diamond Graphite Eclogite from the Roberts Victor MineProceedings of Second International Kimberlite Conference, Proceedings Vol. PP. 29-36.South AfricaPetrography
DS1975-1112
1979
Gurney, J.J.Lawless, P.J., Gurney, J.J., Dawson, J.B.Polymict Peridotites from the Bultfontein and de Beers Mines,kimberley South Africa.Proceedings of Second International Kimberlite Conference, Proceedings Vol. 2, PP. 145-155.South AfricaPetrography
DS1975-1153
1979
Gurney, J.J.Meyer, H.O.A., Tsai, H.M., Gurney, J.J.A Unique Enstatite Megacryst with Co-existing Chromium Poor and Chromium Rich Garnet Weltevreden Floors, South Africa.Proceedings of Second International Kimberlite Conference, Proceedings Vol. 2, PP. 279-281.South AfricaPetrography
DS1975-1217
1979
Gurney, J.J.Shee, S.R., Gurney, J.J.The Mineralogy of Xenoliths from Orapa, BotswanaProceedings of Second International Kimberlite Conference, Vol. 2, PP. 37-49.BotswanaBlank
DS1980-0154
1980
Gurney, J.J.Gurney, J.J.Diamond Riches in the RollersIndiaqua., 1980/3. No. 26, PP. 17-22.South AfricaMarine Placers, Diamond Mining Recovery
DS1980-0155
1980
Gurney, J.J.Gurney, J.J., Harte, B.Chemical Variation in Upper Mantle Nodules from Southern African Kimberlites.Royal Society of London PHIL. Transactions, Vol. 297, No. 1431, PP. 273-294.South AfricaMineral Chemistry
DS1980-0162
1980
Gurney, J.J.Harte, B., Gurney, J.J., Harris, J.W.The Formation of Peridotitic Suite Inclusions in DiamondsContributions to Mineralogy and Petrology, Vol. 72, pp. 181-90.South Africa, TanzaniaPeridotite, Diamond Inclusions
DS1980-0172
1980
Gurney, J.J.Hervig, R.L., Smith, J.V., Steele, I.M., Gurney, J.J., Meyer, H.Diamonds: Minor Elements in Silicate Inclusions: Pressure Temperature Implications.Journal of Geophysical Research, Vol. 85, No. B 12, DECEMBER 10TH. PP. 6919=6929.GlobalMineralogy
DS1981-0197
1981
Gurney, J.J.Gurney, J.J.The Monastery MineIndiaqua., 1981/2, No. 29, PP. 21-24.South AfricaGeology, History
DS1981-0204
1981
Gurney, J.J.Harte, B., Gurney, J.J.The Mode of Formation of Chromium Poor Megacryst Suites From Kimberlites.Journal of GEOLOGY, Vol. 89, No. 6, PP. 749-753.South AfricaKimberlite, Genesis, Model
DS1982-0112
1982
Gurney, J.J.Boyd, F.R., Gurney, J.J.Low Calcium Garnets: Keys to Craton Structure and Diamond Chromiumystallization.Carnegie Institute Yearbook, FOR 1981, PP. 261-267.South Africa, Lesotho, Southwest Africa, NamibiaOrigin, Kimberlites
DS1982-0230
1982
Gurney, J.J.Gurney, J.J., Boyd, F.R.Mineral Intergrowths with Polycrystalline Diamonds from The Orapa Mine, Botswana.Carnegie Institute Yearbook, FOR 1981, PP. 267-273.BotswanaMineralogy
DS1982-0231
1982
Gurney, J.J.Gurney, J.J., Harris, J.W.Some Observations Relevant to the Formation of Natural Diamonds.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 199, (abstract.).GlobalMorphology, Chemistry, Peridotite, Xenolith
DS1982-0232
1982
Gurney, J.J.Gurney, J.J., Harris, J.W.Some Observations on the Formation of Natural DiamondUnknown, 35P.South AfricaFinsch, Koffiefontein, Orapa, Roberts Victor, Premier, Inclusion
DS1982-0233
1982
Gurney, J.J.Gurney, J.J., Harris, J.W., Richard, R.S.Silicate and Oxide Inclusions in Diamonds from Orapa Mine, Botswana.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 201, (abstract.).BotswanaKimberlite, Garnet, Eclogite, Websterite
DS1982-0234
1982
Gurney, J.J.Gurney, J.J., Harris, J.W., Rickard, R.S.The Abundance and Chemistry of Minerals Associated with Diamonds at Roberts Victor Mine.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 200, (abstract.).South AfricaKimberlite, Chemistry, Olivine, Harzburgite, Garnet, Eclogite
DS1982-0235
1982
Gurney, J.J.Gurney, J.J., Walker, C.S.H., et al.Diamond Recoveries Near the Surf Zone of the Namaqualand Coast Near the olifants River.Sedimentology 82, Abstract Volume, Third Symposium of The, PP. 84-88.South AfricaMining, Alluvial, Methods, Recovery
DS1982-0252
1982
Gurney, J.J.Harris, J.W., Gurney, J.J.The Abundance, Mineralogy and Chemistry of Sulphide Inclusions in Diamonds.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 201, (abstract.).South AfricaKimberlite, Premier, Finsch, Jagersfontein, Orapa, Roberts Victor
DS1982-0254
1982
Gurney, J.J.Harte, B., Gurney, J.J.Compositional and Textural Features of Peridotite Nodules from the jagersfontein Kimberlite Pipe, South Africa.Proceedings of Third International Kimberlite Conference, TERRA, Vol. 2, No. 3, PP. 256-257, (abstract.).South AfricaKimberlite
DS1982-0270
1982
Gurney, J.J.Helmstaedt, H., Gurney, J.J.Kimberlites of Southern Africa- are they Related to Subduction Processes? #1Proceedings of Third International Kimberlite Conference, TERRA, Vol. 2, No. 3, PP. 272-273, (abstract.).South AfricaKimberlite, Genesis
DS1982-0522
1982
Gurney, J.J.Robinson, D.N., Shee, S.R., Gurney, J.J.Diamond and Graphite Eclogite from OrapaProceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 202, (abstract.).BotswanaKimberlite, Mineralogy, Xenoliths
DS1982-0562
1982
Gurney, J.J.Shee, S.R., Gurney, J.J., Robinson, D.N.Two Diamond Bearing Peridotite Xenoliths from the Finsch Kimberlite, South Africa.Contributions to Mineralogy and Petrology, Vol. 81, No. 2, PP. 79-87.South AfricaBlank
DS1983-0196
1983
Gurney, J.J.Deines, P., Gurney, J.J., Harris, J.W.Associated Chemical and Carbon Isotopic Composition Variations in Diamonds from the Finsch and Premier Kimberlite, South Africa. #1Reprint., 46P. 9FIG.South AfricaGenesis, Diamonds, Kimberlite, Inclusions, Mineral Chemistry
DS1983-0268
1983
Gurney, J.J.Gurney, J.J.Sea Diamond DevelopmentsIndiaqua., No. 36, 1983/3, PP. 13; 15; 16-17; 19.South AfricaHistory, Mining, Marine Placer Deposits
DS1984-0227
1984
Gurney, J.J.Deines, P., Gurney, J.J., Harris, J.W.Associated Chemical and Carbon Isotopic Composition Variations in Diamonds from the Finsch and Premier Kimberlite, South Africa. #2Geochimica Et Cosmochimica Acta, Vol. 48, No. 2, FEBRUARY, PP. 325-342.South AfricaMineral Chemistry, Isotope, Chronology
DS1984-0325
1984
Gurney, J.J.Gurney, J.J.Some Aspects of Kimberlite GenesisKimberlite Occurrence And Origin A Basis For Conceptual Mode, PP. 15-16. (abstract.).GlobalGenesis, Mineralogy, Isotope, Marid, Premier, Geochronology
DS1984-0326
1984
Gurney, J.J.Gurney, J.J.The Association Between G10 Garnets and DiamondsKimberlite Occurrence And Origin A Basis For Conceptual Mode, PP 17-18. (abstract.).GlobalXenocrysts, Potential, Diamond, Content
DS1984-0327
1984
Gurney, J.J.Gurney, J.J.A Correlation Between Garnets and Diamonds in KimberlitesUniversity of Western Australia - Special Publication, No. 8, PP. 143-166.South Africa, United States, Colorado PlateauMineral Inclusions
DS1984-0328
1984
Gurney, J.J.Gurney, J.J., Harris, J.W., Rickard, R.S.Silicate and Oxide Inclusions in Diamonds from the Orapa Mine, Botswana.Proceedings of Third International Kimberlite Conference., Vol. 2, PP. 3-9.BotswanaAnalyses, Geothermometry, Geobarometry, Mineral Chemistry
DS1984-0329
1984
Gurney, J.J.Gurney, J.J., Harris, J.W., Rickard, R.S.Minerals Associated With Diamonds from the Roberts Victor MineProceedings of Third International Kimberlite Conference, Vol. 2, PP. 25-32.South AfricaAnalyses, Isotope, Mineral Chemistry
DS1984-0352
1984
Gurney, J.J.Helstaedt, H., Gurney, J.J.Kimberlites of Southern Africa- are they Related to Subduction Processes? #2Proceedings of Third International Kimberlite Conference., Vol. 1, PP. 425-434.South Africa, Botswana, LesothoDistribution, Kimberlite, Genesis, Xenolith
DS1984-0607
1984
Gurney, J.J.Richardson, S.H., Gurney, J.J., Erlank, A.J., Harris, J.W.Origin of Diamonds in Old Enriched MantleNature., Vol. 310, No. 5974, JULY 19TH. PP. 198-202.South AfricaBultfontein, Finsch, Kimberley, Geochronology, Genesis
DS1984-0610
1984
Gurney, J.J.Robinson, D.N., Gurney, J.J., Shee, S.R.Diamond Eclogite and Graphite Eclogite Xenoliths from Orapa, Botswana.Proceedings of Third International Kimberlite Conference., Vol. 2, PP. 10-24.BotswanaChemical Analyses, Inclusions
DS1985-0082
1985
Gurney, J.J.Boyd, F.R., Gurney, J.J., Richardson, S.H.Evidence for a 150-200 Km Thick Archaean Lithosphere from Diamond Inclusion Thermobarometry.Nature., Vol. 315, No. 6018, MAY 30TH. PP. 387-388.South AfricaInclusions, Garnet, Mineral Chemistry, Geobarometry, Analyses
DS1985-0254
1985
Gurney, J.J.Gurney, J.J., Harris, J.W., Rickard, . R.S., Moore, R.O.Inclusions in Premier Mine DiamondsTransactions Geological Society of South Africa, Vol. 88, pt. 2, May-August pp. 301-310South AfricaMineralogy, Geothermometry
DS1985-0462
1985
Gurney, J.J.Moore, R.O., Gurney, J.J.Pyroxene Solid Solutions in Garnets Included in DiamondNature, Vol. 318, No. 6046, Dec. 12, pp. 553-555South AfricaMineral Chemistry, Diamond Morphology
DS1985-0463
1985
Gurney, J.J.Moore, R.O., Gurney, J.J.Pyroxene solid solution in garnets included in diamonds from the Monastery mine kimberliteTransactions Geological Society of South Africa, Vol. 88, pt. 2, May-August p. 477. abstractSouth AfricaMonastery, Geochemistry
DS1985-0623
1985
Gurney, J.J.Smith, C.B., Gurney, J.J., Skinner, E.M.W., Clement, C.R., Ebrahim, N.Geochemical character of Southern African kimberlites: a new approach based on isotopic constraintsTransactions Geological Society of South Africa, Vol. 88, pt. 2, May-August pp. 267-280South AfricaGeochemistry, Geochronology
DS1986-0098
1986
Gurney, J.J.Boyd, F.R., Gurney, J.J.Diamonds and the African lithosphereScience, Vol. 232, April 25th. pp. 472-477South AfricaKaapvaal craton, inclusions, genesis, xenoliths, Diamond morphology
DS1986-0164
1986
Gurney, J.J.Daniels, L.R.M., Gurney, J.J.The chemistry of concentrate minerals and diamond inclusions of the Dokolwayo kimberlite, SwazilandProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 380-382GlobalDiamond morphology
DS1986-0178
1986
Gurney, J.J.Deines, P., Harris, J.W., Gurney, J.J.On the existence of C-13 depleted carbon in the mantle, evidence From diamond studiesProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 383-385South AfricaRoberts Victor, Diamond morphology
DS1986-0322
1986
Gurney, J.J.Gurney, J.J.Diamonds #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 363-367GlobalReview paper
DS1986-0323
1986
Gurney, J.J.Gurney, J.J., Harris, J.W., Rickard, R.S., Cardoso, P.Mineral inclusions in diamonds from Koffiefontein mineProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 389-391South AfricaKoffiefontein, Diamond morphology
DS1986-0324
1986
Gurney, J.J.Gurney, J.J., Hatton, C.J.Diamondiferous minerals from the Star mine, South Africa #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 392-394South AfricaStar mine
DS1986-0370
1986
Gurney, J.J.Hops, J.J., Gurney, J.J., Harte, B.Megacrysts and deformed nodules from the Jagersfontein kimberlite pipeProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 256-258South AfricaBlank
DS1986-0445
1986
Gurney, J.J.Kirkley, M.D., Smith, H.S., Gurney, J.J.Kimberlite carbonates: a carbon oxygen stable isotope studyProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 57-59South AfricaWesselton, Isotope
DS1986-0470
1986
Gurney, J.J.Kurz, M.D., Gurney, J.J.Helium isotopic heterogeneity within single diamonds from the Orapa kimberlite pipeProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 401-402BotswanaDiamond morphology
DS1986-0543
1986
Gurney, J.J.McCandless, T.E., Gurney, J.J.Sodium in garnet and potassium in clinopyroxene: criteria forclassifying mantle eclogites #1Proceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 282-284South AfricaEclogite
DS1986-0580
1986
Gurney, J.J.Moore, R.O., Gurney, J.J.Mineral inclusions in diamonds from the Monastery kimberlite,SouthAfricaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 406-408South AfricaDiamond morphology
DS1986-0581
1986
Gurney, J.J.Moore, R.O., Otter, M.L., Rickard, R.S., Harris, J.W., Gurney, J.J.The occurrence of moissanite and ferro-periclase as inclusionsindiamondProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 409-411South Africa, ColoradoMonastery, Sloan, Diamond morphology
DS1986-0627
1986
Gurney, J.J.Otter, M.L., Gurney, J.J.Mineral inclusions in diamonds from the Sloan diatremes,Colorado-Wyoming State line kimberlite district, North AmericaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 415-417ColoradoDiamond inclusions
DS1986-0751
1986
Gurney, J.J.Smith, C.B., Allsopp, H.L., Kramers, J.D., Gurney, J.J., JagoutzIsotopic and geochemical studies of kimberlitic and included xenolithsProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 329-331South Africa, BotswanaBlank
DS1986-0753
1986
Gurney, J.J.Smith, C.B., Gurney, J.J., Harris, J.W., Robinson, D.N., Shee, S.R.Strontium and neodymium isotopic systematics of diamond bearing eclogite xenoliths and eclogitic inclusions in diamond from southernAfricaProceedings of the Fourth International Kimberlite Conference, Held, No. 16, pp. 332-334South AfricaEclogite
DS1987-0146
1987
Gurney, J.J.Deines, P., Harris, J.W., Gurney, J.J.Carbon isotope composition, nitrogen content and inclusion composition Of diamonds from the Roberts Victor kimberlite, South Africa- evidence for C 13depletion in tGeochem. Cosmochem.Acta, Vol. 51, No. 5, May pp. 1227-1243South AfricaRoberts Victor, Isotope
DS1987-0263
1987
Gurney, J.J.Gurney, J.J., Moore, R.O.Diamonds and inclusions: remnants of old lithosphere?Terra Cognita, Conference abstracts Oceanic and Continental Lithosphere:, Vol. 7, No. 4, Autumn, abstract only p. 614South AfricaBlank
DS1987-0278
1987
Gurney, J.J.Harte, B., Winterburn, P.A., Gurney, J.J.Metasomatic and enrichment phenomena in garnet peridotite facies mantle xenoliths from the Matsoku kimberlite pipe, LesothoIn: Mantle Metasomatism, edited M.A. Menzies, C.J. Hawkesworth, Academic, pp. 145-220LesothoBlank
DS1987-0280
1987
Gurney, J.J.Hatton, C.J., Gurney, J.J.Roberts Victor eclogites and their relation to the mantlein: Nixon, P.H. ed. Mantle xenoliths, J. Wiley, pp. 453-464South AfricaBlank
DS1987-0390
1987
Gurney, J.J.Kurtz, M.D., Gurney, J.J., Jenkins, M.J., Lott, D.E.Helium isotopic variability within single diamonds from the Orapa kimberlite pipeEarth Planet. Sci. Letters, Vol. 86, No. 1, November pp. 57-68BotswanaBlank
DS1988-0633
1988
Gurney, J.J.Shimizu, N., Gurney, J.J., Moore, R.O.Trace element abundance patterns of garnet inclusions in diamondsV.m. Goldschmidt Conference, Program And Abstract Volume, Held May, p. 74. AbstractSouth AfricaBlank
DS1989-0327
1989
Gurney, J.J.Daniels, L.R.M., Gurney, J.J.The chemistry of the garnets, chromites and diamond inclusions of the Dokolwayo kimberlite, Kingdom ofSwazilandGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 1012-1021GlobalMineral chemistry, Diamond inclusions, Garnet
DS1989-0349
1989
Gurney, J.J.Deines, P., Harris, J.W., Spear, P.M., Gurney, J.J.Nitrogen and C-13 content of Finsch and Premier diamonds and theirimplicationsGeochimica et Cosmochimica Acta, Vol. 53, No. 6, June pp. 1367-1378South AfricaDiamond morphology, Diamond inclusions
DS1989-0550
1989
Gurney, J.J.Griffin, W.L., Gurney, J.J., Ryan, C.G., Cousens, D.R., Sie, S.H.Trapping temperatures and trace elements in P type garnets indiamonds:a proton microprobe studyDiamond Workshop, International Geological Congress, July 15-16th. editors, pp. 23-25. AbstractSouth AfricaGeochemistry Analyses, Diamond morphology
DS1989-0560
1989
Gurney, J.J.Gurney, J.J.Kasai capersIndiaqua, No. 52, 1989/I, pp. 33, 35-36Democratic Republic of CongoHistory, overview (M'buji Mayi, )Tshikapa, Alluvial placers
DS1989-0561
1989
Gurney, J.J.Gurney, J.J.Diamond Morphology #1Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 2, pp. 935-965GlobalReview paper, Diamond Morphology, Ages, Distribution, placer
DS1989-0562
1989
Gurney, J.J.Gurney, J.J., Hatton, C.J.Diamondiferous minerals from the Star mine, South Africa #2Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 2, pp. 1022-1028South AfricaDeposit -Star, Diamond inclusions, Garnet
DS1989-0563
1989
Gurney, J.J.Gurney, J.J., McCandless, T.E., Kirkley, M.B., Robinson, D.N.Some initial observations on polycrystalline diamonds mainly from Orapa:abstractDiamond Workshop, International Geological Congress, July 15-16th. editors, BotswanaAnalyses, Diamond morphology
DS1989-0660
1989
Gurney, J.J.Hops, J.J., Gurney, J.J., Harte, B., Winterburn, P.Megacrysts and high temperature nodules from the Jagersfontein kimberliteGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 759-770South AfricaPetrography, Geothermobarometry
DS1989-0784
1989
Gurney, J.J.Kirkley, M.B., Gurney, J.J.Carbon isotope modelling of biogenic origins for carbon in eclogiticdiamondsDiamond Workshop, International Geological Congress, July 15-16th. editors, pp. 40-43. AbstractSouth AfricaInclusions, Eclogite Roberts Victor, A.
DS1989-0785
1989
Gurney, J.J.Kirkley, M.B., Smith, H.S., Gurney, J.J.Kimberlite carbonates - a carbon and oxygen stable isotope studyGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 1, pp. 264-281South Africa, BotswanaGeochronology, Stable isotopes
DS1989-0972
1989
Gurney, J.J.McCandless, T.E., Gurney, J.J.Sodium in garnet and potassium in clinopyroxene:criteria for classifying mantle eclogites #2Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 2, pp. 827-832South AfricaDiamond morphology, Diamond eclogite
DS1989-0973
1989
Gurney, J.J.McCandless, T.E., Kirkley, M.B., Robinson, D.N., Gurney, J.J.Some initial observations on polycrystalline diamonds mainly from Orapa:Diamond Workshop, International Geological Congress, July 15-16th. editors, pp. 47-51BotswanaDiamond morphology, Diamond aggregates
DS1989-1050
1989
Gurney, J.J.Moore, R.O., Gurney, J.J.Mineral inclusions in diamond from the Monasterykimberlite, SouthAfricaGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 1029-1041South AfricaDeposit -Monastery, Diamond inclusions, Garnet
DS1989-1051
1989
Gurney, J.J.Moore, R.O., Gurney, J.J., Griffin, W.L.Trace element abundance patterns in diamond inclusions from the MonasteryMine, South AfricaDiamond Workshop, International Geological Congress, July 15-16th. editors, pp. 65-68. AbstractSouth AfricaDiamond Inclusions -Monastery, Diamond morphology
DS1989-1156
1989
Gurney, J.J.Otter, M.L., Gurney, J.J.Mineral inclusions in diamonds from the Sloan diatreme, Colorado-Wyoming State Line kimberlite district, North AmericaGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 1042-1053Colorado, WyomingDiamond inclusions, Deposit -Sloan diatremes
DS1989-1157
1989
Gurney, J.J.Otter, M.L., Gurney, J.J., McCandless, T.E.The carbon isotope composition of Sloan diamonds #1Diamond Workshop, International Geological Congress, July 15-16th., pp. 76-79. AbstractColoradoGeochronology -Carbon Isotope, Deposit -Sloan diatremes
DS1989-1270
1989
Gurney, J.J.Rickard, R.S., Harris, J.W., Gurney, J.J., Cardos, P.Mineral inclusions in diamonds from the Koffiefontein mineGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 1054-1062South AfricaDiamond inclusions, Deposit -Koffiefontein
DS1989-1384
1989
Gurney, J.J.Shimizu, N., Gurney, J.J., Moore, R.Trace element geochemistry of garnet inclusions in diamonds from The finsch and Koffiefontein kimberlite pipes #2Diamond Workshop, International Geological Congress, July 15-16th., pp. 100-101. AbstractSouth AfricaDiamond Inclusions, Diamond morphology
DS1989-1385
1989
Gurney, J.J.Shimizu, N., Gurney, J.J., Moore, R.Trace element geochemistry of garnet inclusions in diamonds from The finsch and Koffiefontein kimberlite pipes #1Geological Society of America (GSA) Annual Meeting Abstracts, Vol. 21, No. 6, p. A361. AbstractSouth AfricaGeochemistry, Diamond Inclusions
DS1989-1407
1989
Gurney, J.J.Smith, C.B., Gurney, J.J., Harris, J.W., Otter, M.L., Kirkley, M.B.neodymium and Strontium isotope systematics of large eclogite and lherzolite paragenesis single diamonds,Finsch and Kimberley PoolDiamond Workshop, International Geological Congress, July 15-16th., pp. 102-104. AbstractSouth AfricaDiamond morphology, Eclogite, Geochronology
DS1989-1408
1989
Gurney, J.J.Smith, C.B., Gurney, J.J., Harris, J.W., Robinson, D.N., Shee, S.R.Sm and neodymium isotopic systematics of diamond bearing eclogite xenoliths and eclogitic inclusions in diamond from southern AfricaGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 853-863South AfricaDiamond inclusions, Diamond eclogite
DS1990-0623
1990
Gurney, J.J.Gurney, J.J.The Diamondiferous roots of our wandering continent. Alex L. du To it Memorial Lectures no. 21South African Journal of Geology, Vol. 93, No. 3, pp. 423-437South AfricaMantle, Diamond genesis
DS1990-0624
1990
Gurney, J.J.Gurney, J.J., Kirkley, M.B.Roberts Victor eclogites : crustal origins reconsideredEos, Vol. 71, No. 17, April 24, p. 523 Abstract onlySouth AfricaEclogites, Xenoliths
DS1990-0840
1990
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Otter, M.L., Hill, S.J.Modeling subducted crustal carbon sources for eclogitic diamondsEos, Vol. 71, No. 17, April 24, p. 644 Abstract onlySouth Africa, Colorado, WyomingEclogitic diamond genesis, Geochronology -carbon
DS1990-1143
1990
Gurney, J.J.Otter, M.L., Gurney, J.J., McCandless, T.E.The carbon isotope composition of Sloan diamonds #2Eos, Vol. 71, No. 17, April 24, p. 644 Abstract onlyColorado, WyomingDiamond genesis, Geochronology -carbon iso
DS1990-1571
1990
Gurney, J.J.Winterburn, P.A., Harte, B., Gurney, J.J.Peridotite xenoliths from the Jagersfontein kimberlite pipe: 1. Primary and primary-metasomatic mineralogyGeochimica et Cosmochimica Acta, Vol. 54, pp. 329-341South AfricaXenolith mineralogy, Deposit - Jagersfontein
DS1991-0335
1991
Gurney, J.J.Daniels, L.R.M., Gurney, J.J.Oxygen fugacity constraints on the southern African lithosphereContributions to Mineralogy and Petrology, Vol. 108, No. 1-2, pp. 154-161GlobalMantle, Geothermometry- oxygen fugacity
DS1991-0363
1991
Gurney, J.J.Deines, P., Harris, J.W., Gurney, J.J.The carbon isotopic composition and nitrogen content of lithospheric and asthenospheric diamonds from the Jagersfontein kimberlite, South AfricaGeochimica et Cosmochimica Acta, Vol. 55, pp. 2615-2625South AfricaGeochronology, CI, Nitrogen, Jagersfontein
DS1991-0364
1991
Gurney, J.J.Deines, P., Harris, J.W., Robinson, D.N., Gurney, J.J., Shee, S.R.Carbon and isotope oxygen variations in diamond and graphite eclogites fromOrapa, Botswana and the nitrogen content of their diamondsGeochimica et Cosmochimica Acta, Vol. 55, No. 2, February pp. 515-524BotswanaEclogites, Geochronology, isotopes
DS1991-0607
1991
Gurney, J.J.Griffin, W.L., Gurney, J.J., Sobolev, N.V., Ryan, C.G.Comparative geochemical evolution of cratonic lithosphere: South Africa andSiberiaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 119-121South Africa, RussiaGeochemistry, Craton, mineralogy
DS1991-0610
1991
Gurney, J.J.Griffin, W.L., Ryan, C.G., Gurney, J.J., Sobolev, N.V., Win, T.T.Chromite macrocrysts in kimberlites and lamproites: geochemistry and origin #1Proceedings of Fifth International Kimberlite Conference held Araxa June, pp. 142-144South Africa, RussiaGeochemistry -chrome-spinels, Mantle, exploration
DS1991-0631
1991
Gurney, J.J.Gurney, J.J.Diamonds deliver the dirtNature, Vol. 353, Oct. 17, pp. 601-602GlobalMantle -Diamond morphology, Diamond inclusions
DS1991-0632
1991
Gurney, J.J.Gurney, J.J.Different crystallographic forms of diamond: origin and postcrystallization historyXiii International Gemmological Conference Held South Africa, Stellenbosch, 2p. abstractGlobalNatural diamond, Diamond morphology
DS1991-0633
1991
Gurney, J.J.Gurney, J.J.Comparison of Siberian and South African Diamondiferous kimberlitesConference registration The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Xerox Tower Suite 1210, 3400 de Maissoneuve, Sept. 5-13, 1991 Fax 514 939-2714Russia, South AfricaKimberlites, Economics
DS1991-0634
1991
Gurney, J.J.Gurney, J.J., Moore, R.O.Geochemical correlations between kimberlitic indicator minerals And diamonds as applied to explorationProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 125-126GlobalDiamond potential, Peridotite, eclogite
DS1991-0635
1991
Gurney, J.J.Gurney, J.J., Moore, R.O.Diamond resources on the continental shelf of southern AfricaThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin) ., Session on Diamonds at The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Annual Meeting April, Vol. 84, No. 947, March p. 99. AbstractSouthwest Africa, NamibiaAlluvials -sea, Recovery
DS1991-0636
1991
Gurney, J.J.Gurney, J.J., Moore, R.O., Griffin, W.L., Sobolev, N.V.The use of macrocryst minerals to predict diamond potential in kimberlites based on Southern Africa and a comparison with SiberiaGeological Society The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) First Annual Field Conference symposium held, 2pg. abstractSouth Africa, RussiaDiamond potential, Garnet, nickel thermometry
DS1991-0637
1991
Gurney, J.J.Gurney, J.J., Moore, R.O., Otter, M.L., Kirkley, M.B., Hops, J.J.Southern African kimberlites and their xenolithsMagmatism in Extensional structural settings, Springer pp. 495-536.South Africa, Botswana, Zimbabwe, Lesotho, SwazilandKimberlites, Review
DS1991-0678
1991
Gurney, J.J.Harte, B., Matthews, M.B., Winterburn, P.A., Gurney, J.J.Aspects of melt composition, crystallization, metasomatism anddistribution, shown by mantle xenoliths from the Matsoku kimberlite pipeProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 167-169South AfricaMantle, Metasomatism
DS1991-0730
1991
Gurney, J.J.Hops, J.J., Moore, R.O., Gurney, J.J.The individuality of on and off craton megacryst suites in SouthernAfricaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 177-179South Africa, SwazilandMonastery, Granny Smith, Dokolwayo, Barkly West, Mineral chemistry
DS1991-0875
1991
Gurney, J.J.Kirkley, M.B., Gurney, J.J.Diamonds from algae: organic sources for carbon in diamondsXiii International Gemmological Conference Held South Africa, Stellenbosch, 1p. abstractGlobalGeochemistry, Diamond
DS1991-0876
1991
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Harte, J.J., Helmstaedt, H.Geochemical correlations in Roberts Victor eclogitesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, p. 224South AfricaGeochemistry, Eclogite xenoliths
DS1991-0877
1991
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Levinson, A.A.Age, origin, and emplacement of diamonds: scientific advances in the lastdecadeGems and Gemology, Vol. XXVII, Spring pp. 2-25GlobalDiamond genesis, Overview -review/update
DS1991-0878
1991
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Levinson, A.A.Age, origin and emplacement of diamonds: a review of the scientific advances in the decade 1981-1990The Canadian Mining and Metallurgical Bulletin (CIM Bulletin) ., Session on Diamonds at The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Annual Meeting April, Vol. 84, No. 947, March p. 90. AbstractGlobalOrigin -source of carbon, Emplacement mechanisM.
DS1991-0879
1991
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Otter, M.L., Hill, S.J., Daniels, L.R.The application of Carbon isotope measurements to the identification of the sources of C in diamonds: a reviewApplied Geochemistry, Vol. 6, No. 5, pp. 477-494GlobalGeochronology, Carbon, diamonds
DS1991-0880
1991
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Rickard, R.S.Jwaneng framesites -inclusions and carbon isotopesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 225-227BotswanaJwaneng, framesites, Geochronology
DS1991-1091
1991
Gurney, J.J.McCandless, T.E., Waldman, M.A., Gurney, J.J.Macro and micro diamonds from Arkansaw lamproites: morphology, inclusion sand isotope geochemistryProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 264-266ArkansasDiamond morphology, Diamond inclusions, comparison to Ellendale
DS1991-1186
1991
Gurney, J.J.Moore, R.O., Gurney, J.J.Garnet megacrysts from Group II kimberlites in southern AfricaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 298-300GlobalDokolwayo, garnets, compositional trends, Geochemistry, trace elements
DS1991-1187
1991
Gurney, J.J.Moore, R.O., Gurney, J.J., Fipke, C.E.Geochemical correlations between kimberlitic indicator minerals And diamonds #1The Canadian Mining and Metallurgical Bulletin (CIM Bulletin) ., Session, Vol. 84, No. 947, March p. 90. AbstractSouth AfricaGeochemistry, Macrocrysts -garnet and chromite
DS1991-1274
1991
Gurney, J.J.Otter, M.L., Gemeke, D.A., Harte, B., Gurney, J.J., Harris, J.W.Diamond growth histories revealed by cathodluminescence and carbon isotopestudiesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 318-319Southern AfricaPremier, Bultfontein, Finsch, Koffiefontein, Geochronology
DS1991-1275
1991
Gurney, J.J.Otter, M.L., Gurney, J.J.Primary diamond subpopulations at individual localitiesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, p. 322GlobalDiamond inclusions, Geothermometry
DS1991-1276
1991
Gurney, J.J.Otter, M.L., Gurney, J.J., McCallum, M.E.A physical characterization of the Sloan diamondsProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 320-321Colorado, WyomingState Line, diamond inclusions, Diamond morphology
DS1991-1422
1991
Gurney, J.J.Rickard, R.S., Gurney, J.J., Harris, J.W.Mineral inclusions in diamonds from Jagersfontein mineProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 336-338South AfricaDiamond inclusions, Peridotite, mineral chemistry, analyses
DS1991-1607
1991
Gurney, J.J.Smith, C.B., Gurney, J.J., Harris, J.W., Otter, M.L., Kirkley, M.B.Neodynium and strontium isotope systematics of eclogite and websterite paragenesis inclusions from single diamonds, Finsch and Kimberley Pool, RSA.Geochimica et Cosmochimica Acta, Vol. 55, pp. 2579-2590South AfricaGeochronology, Eclogite, websterite, diamond morphology
DS1991-1615
1991
Gurney, J.J.Smith, H.S., Gurney, J.J.Marine diamonds - a sleeping giantIndustrial Minerals, Advertisement for Institute of Mining and Metallurgy (IMM) Alluvial Mining Conference, Paper to be presentedSouthern AfricaNews item, Conference paper
DS1992-0615
1992
Gurney, J.J.Griffin, W.L., Gurney, J.J., Ryan, C.G.Variations in trapping temperatures and trace elements in peridotite-suite inclusions African diamonds- evidence 2 inclusion suites implications lithosphere stratigrContributions to Mineralogy and Petrology, Vol. 110, No. 1, March pp. 1-15South AfricaDiamond inclusions, Lithosphere stratigraphy
DS1992-0618
1992
Gurney, J.J.Griffin, W.L., Ryan, C.G., Gurney, J.J., Sobolev, N.V.Comparative geochemical evolution of the Australian, southern Africa and Siberian cratonic lithosphere11th. Australian Geol. Convention Held Ballarat University College, Jan., AbstractAustralia, South Africa, RussiaCraton, Geochemistry
DS1992-0619
1992
Gurney, J.J.Griffin, W.L., Ryan, C.G., Gurney, J.J., Sobolev, N.V.Comparative geochemical evolution of the southern African, Siberian and Australian cratonic lithosphereProceedings of the 29th International Geological Congress. Held Japan August 1992, Vol. 1, abstract p. 175South Africa, Russia, AustraliaGeochronology, Craton
DS1992-0620
1992
Gurney, J.J.Griffin, W.L., Ryan, C.G., Moore, R.O., Gurney, J.J.Geochemistry of magnesian ilmenites from kimberlites and basaltsV.m. Goldschmidt Conference Program And Abstracts, Held May 8-10th. Reston, p. A 44. abstractSouth AfricaGeochemistry, Magnesian ilmenites
DS1992-0636
1992
Gurney, J.J.Gurney, J.J., Harris, J.W.The Kalahari craton: Clifford's rule reflects diamond's ancient originsRussian Geology and Geophysics, Vol. 33, No. 10, pp. 32-34South AfricaCraton, Diamond inclusions
DS1992-0637
1992
Gurney, J.J.Gurney, J.J., Levinson, A.A., Smith, H.S.Marine mining of diamonds off the west coast of southern AfricaGems and Gemology, Vol. 27, No. 4, pp. 206-219Southwest Africa, Namibia, South AfricaMarine mining, Orange River, Alluvial diamonds
DS1992-0638
1992
Gurney, J.J.Gurney, J.J., Moore, R.O.Geochemical correlation between kimberlite indicator minerals and diamond son the Kalahari cratonInternational Roundtable Conference on Diamond Exploration and Mining, held, pp. 58-81South AfricaMineral chemistry, Geochemistry
DS1992-0727
1992
Gurney, J.J.Hops, J.J., Gurney, J.J., Harte, B.The Jagersfontein chromium-poor megacryst suite -towards a model for megacrystpetrogenesisJournal of Volcanology and Geothermal Research, Vol. 50, pp. 143-160South AfricaPetrogenesis, Deposit -Jagersfontein
DS1992-0866
1992
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Harte, B.rare earth elements (REE) characteristics of garnets and clinopyroxenes in eclogite xenoliths from the Roberts Victor kimberliteV.m. Goldschmidt Conference Program And Abstracts, Held May 8-10th. Reston, p. A 60. abstractSouth AfricaGeochronology, Roberts Victor
DS1992-0867
1992
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Levinson, A.A.Age, origin and emplacement of diamonds: a review of scientific advances In the last decade.reprinted from Gems and Gemology with some revisionThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 85, No. 956, January pp. 48-57GlobalDiamond exploration - techniques, Diamond genesis
DS1992-0940
1992
Gurney, J.J.Levinson, A.A., Gurney, J.J., Kirkley, M.B.Diamond sources and production: past, present and futureGems and Gemology, Vol. 28, No. 4, Winter pp. 234-254GlobalReview, Production, current activities
DS1992-1082
1992
Gurney, J.J.Moore, R.O., Griffin, W.L., Gurney, J.J., Ryan, C.G., Cousens, D.R.Trace element geochemistry of ilmenite megacrysts from the Monasterykimberlite, South Africa.Lithos, Vol. 29, No. 1-2, December pp. 1-18.South AfricaGeochemistry, Ilmenites
DS1992-1420
1992
Gurney, J.J.Skinner, E.M.W., Clement, C.R., Gurney, J.J., Apter, D.B., Hatton, C.J.The distribution and tectonic setting of South African kimberlitesRussian Geology and Geophysics, Vol. 33, No. 10, pp. 26-31.South AfricaTectonics, Kimberlite distribution
DS1993-0337
1993
Gurney, J.J.Deines, P., Harris, J.W., Gurney, J.J.Depth related carbon isotope and nitrogen concentration variability in The mantle below the Orapa kimberlite, Botswana, AfricaGeochemica et Cosmochimica Acta, Vol. 57, No. 12, June pp. 2781-2796BotswanaMantle, Deposit -Orapa
DS1993-0596
1993
Gurney, J.J.Gurney, J.J.Diamond exploration and prospectivity in NamibiaConference on Mining Investment in Namibia, March 17-19th., 1993, Abstracts, pp. 15-17NamibiaBrief overview, Diamond exploration
DS1993-0597
1993
Gurney, J.J.Gurney, J.J.The track record for diamond indicator minerals: a summary of casehistoriesThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin) , Annual Meeting Abstracts approximately 10 lines, Vol. 86, No. 968, March ABSTRACT p. 70South AfricaGeochemistry, Mineral chemistry
DS1993-0598
1993
Gurney, J.J.Gurney, J.J., Helmstaedt, H., Moore, R.O.A review of the use and application of mantle mineral geochemistry in diamond exploration.Pure and Applied Chemistry, Vol. 65, No. 12, December pp. 2423-2442.GlobalGeochemistry, Diamond exploration
DS1993-0599
1993
Gurney, J.J.Gurney, J.J., Helmstaedt, J., Moore, R.O.A review of the use and application of mantle geochemistry in diamondexploration.Pure and Applied Geochemistry, Vol. 65, No. 12, pp. 2423-2442.MantleRoots, Geochemistry
DS1993-0600
1993
Gurney, J.J.Gurney, J.J., Moore, R.L.Geochemical correlations between kimberlitic indicator minerals And diamonds #2Prospectors and Developers Diamond Workshop, held March 27th, Toronto, 23pSouth AfricaGeochemistry, Indicator minerals, diamonds
DS1993-0653
1993
Gurney, J.J.Helmstaedt, H.H., Gurney, J.J.Geotectonic controls on the formation of diamonds and their kimberlitic and lamproitic host rocks: applications to diamond exploration.Proceedings of the Fifth Kimberlite Conference held in Araxam Brasil, Vol. 2, pp. 236-250. 15p.Africa, North AmericaTectonics, diamond genesis, Craton
DS1993-1306
1993
Gurney, J.J.Richardson, S.H., Harris, J.M., Gurney, J.J.3 generations of diamonds from old continental mantleNature, Vol. 366, No. 6452, November 18, pp. 256-258.MantleDiamond, Genesis
DS1994-0666
1994
Gurney, J.J.Griffin, W.L., Ryan, C.G., Gurney, J.J., Sobolev, N.V., Win, T.T.Chromite macrocrysts in kimberlites and lamproites: geochemistry andorigin. #2Proceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 366-377.AustraliaChromite, Geochemistry
DS1994-0679
1994
Gurney, J.J.Gurney, J.J.Diamonds, (C.I.M.) 1994The Canadian Institute of Mining, Metallurgy and Petroleum (CIM), p. 63. abstractGlobalDiamonds
DS1994-0680
1994
Gurney, J.J.Gurney, J.J.Diamonds #2The Canadian Institute of Mining, Metallurgy and Petroleum (CIM), p.63 abstract onlySouth AfricaLithosphere -diamond genesis, Craton -Kaap-Vaal
DS1994-0681
1994
Gurney, J.J.Gurney, J.J.The current status of marine diamond mining off the west coast of Southern africa #2Prospectors and Developers Association of Canada (PDAC) Annual Meeting, Final program abstract volume, p. 50.Southern AfricaAlluvials, Marine mining
DS1994-0682
1994
Gurney, J.J.Gurney, J.J., Moore, R.O.Geochemical correlations between kimberlitic indicator minerals And diamonds on the Kalahari craton.Russian Geology and Geophysics, Vol. 35, No. 2, pp. 9-18.South Africa, BotswanaGeochemistry, Kimberlitic indicator minerals
DS1994-0915
1994
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Rickard, R.S.Jwaneng framesite: carbon isotopes and inclusion compositionsProceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 127-135.BotswanaMineral chemistry, Deposit -Jwaneng
DS1994-1135
1994
Gurney, J.J.McCandless, T.E., Waldman, M.A., Gurney, J.J.Macrodiamonds, microdiamonds from Murfreesboro lamproites: morphology, inclusions, carbon isotope geochemistry.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 78-97.ArkansasDiamond morphology, Deposit -Crater of Diamonds
DS1994-1319
1994
Gurney, J.J.Otter, M.L., McCallum, M.E., Gurney, J.J.A physical characterization of the Sloan (Colorado) diamonds using arevised diamond description scheme.Proceedings of Fifth International Kimberlite Conference, Vol. 2, pp. 15-31.Colorado, United StatesPetrology, Deposit -Sloan
DS1994-1634
1994
Gurney, J.J.Smith, H.S., Gurney, J.J.Recent developments in exploration for marine diamondsThe Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Section, List of speakersNamibia, South AfricaUpdate
DS1995-0120
1995
Gurney, J.J.Baumgartner, M.C., Gurney, J.J.The petrology and geochemistry of a polymict xenolith from the Kimberleyarea, South Africa.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 40.South AfricaXenoliths, Deposit -Kimberley area
DS1995-0133
1995
Gurney, J.J.Bell, D.R., Gurney, J.J., Le Roex, A.P., Moore, R.O, et al.Compositional evolution of the Monastery megacrysts and parent magmaProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 50-51.South AfricaPetrology, Deposit -Monastery
DS1995-0311
1995
Gurney, J.J.Chinn, I.L., Gurney, J.J., Milledge, H.J., Taylor, W.R.Cathodluminescence of CO2 bearing and CO2 free diamonds from the George Creek K1 kimberlite.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 116-17.Colorado, WyomingCathodluminescence, Deposit -George Creek
DS1995-0312
1995
Gurney, J.J.Chinn, I.L., Gurney, J.J., Milledge, H.J., Taylor, W.R.Cathodluminescence properties of CO2 bearing and CO2 free diamonds from the George Creek K1 kimberlite dike.International Geology Review, Vol. 37, pp. 254=258.Colorado, WyomingDiamond morphology, CL properties
DS1995-0543
1995
Gurney, J.J.Fipke, C.E., Gurney, J.J., Moore, R.O.Diamond exploration techniques emphasing indicator mineral geochemistry and Canadian examples.Geological Survey of Canada, Bulletin. 423, 86p. approx. $ 32.00Canada, North AmericaPetrology, kimberlites, lamproites, Exploration techniques
DS1995-0688
1995
Gurney, J.J.Griffin, W.L., Ryan, C.G., O'Reilly, S.Y., Gurney, J.J.Lithosphere evolution beneath the Kaapvaal Craton: 200-80 MaProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 203-4.South AfricaGeothermometry, Craton -Kaapvaal
DS1995-0702
1995
Gurney, J.J.Gurney, J.J.Diamond discovery in the Northwest Territories of CanadaExploration and Mining Geology, Vol. 4, No. 1, p. 86.Northwest TerritoriesBrief overview of exploration
DS1995-0703
1995
Gurney, J.J.Gurney, J.J., Harris, J.W., Otter, M.L., Rickard, R.S.Jwaneng diamond inclusionsProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 208-10.BotswanaDiamond inclusions, Deposit -Jwaneng
DS1995-0704
1995
Gurney, J.J.Gurney, J.J., Smith, H.S.The current status of marine diamond mining off the west coast of southern Africa #1Exploration and Mining Geology, Vol. 4, No. 1, p. 86-87.South Africa, NamibiaMarine mining
DS1995-0705
1995
Gurney, J.J.Gurney, J.J., Zweistra, P.The interpretation of the major element compositions of mantle minerals in diamond exploration.Journal of Geochemical Exploration, Vol. 52, pp. 293-310.South Africa, GlobalDiamond exploration, Evaluation
DS1995-0706
1995
Gurney, J.J.Gurney, J.L., Gurney, J.J.Garnet and ilmenite from some Premier kimberlite intrusivesProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 211-13.South AfricaPetrology, Deposit -Premier
DS1995-0785
1995
Gurney, J.J.Helmstaedt, H., Gurney, J.J.Geotectonic controls of primary diamond deposits: implications for areaselection.Journal of Geochemical Exploration, Vol. 52, pp. 125-144.Northwest TerritoriesDiamond exploration, Area selection
DS1995-0786
1995
Gurney, J.J.Helmstaedt, H.H., Gurney, J.J.Kimberlites -why when and where? a heirarchy of geotectonic controlsProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 233-235.South Africa, Northwest TerritoriesGeotectonics, Craton
DS1995-0794
1995
Gurney, J.J.Hildebrand, P.R., Gurney, J.J.Lithosphere evolution in rifted, craton and mobile belt environments from Zimbabwe and diamond prospectivity.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 236-238.ZimbabweTectonics, Craton, Limpopo Belt
DS1995-0965
1995
Gurney, J.J.Kirkley, M.B., Gurney, J.J., Hill, S.J.Diamond mining on kimberlite dikes of South AfricaProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 277-278.South AfricaGroup II kimberlites -dikes, Deposit - Bellsbank, Bobbejaan, Ardo, Roberts Victor
DS1995-0967
1995
Gurney, J.J.Kivets, G.B., Gurney, J.J., Richardson, S.H. Harris et al.A detailed geochemical study of a suite of Diamondiferous eclogite xenoliths from the Kaavallei.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 279-281.South AfricaEclogites, Deposit -Kaavallei
DS1995-0998
1995
Gurney, J.J.Kopylova, M.G., Gurney, J.J., Daniels, L.R.M.Mineral inclusions in diamonds from the River Ranch kimberliteProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 289-291.ZimbabweDiamond inclusions, Deposit -River Ranch
DS1995-1191
1995
Gurney, J.J.McCammon, C.A., Chinn, I.L., Gurney, J.J., McCallum, M.E.Determination of the ferric iron content of diamond inclusions from George Creek - Mossbauer spectroscopyProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 359-361.WyomingDiamond inclusions, Deposit -George Creek
DS1995-1196
1995
Gurney, J.J.McCandless, T.E., Gurney, J.J.Microdiamonds from kimberlites and lamproites: observations and ideas concerning their origin.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 368-370.Wyoming, South Africa, AustraliaMicrodiamonds, Lamproites
DS1995-1886
1995
Gurney, J.J.Taylor, W.R., Gurney, J.J., Milledge, H.J.Nitrogen aggregation and cathodluminescence characteristics of Diamonds from Point Lake.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 614-616.Northwest TerritoriesCathodluminescence, Deposit -Point Lake
DS1995-1887
1995
Gurney, J.J.Taylor, W.R., Kiviets, G., Gurney, J.J., Milledge, WoodsGrowth history of an eclogitic diamond from the Kaal Vallei kimberlite, an infrared cathodluminescence CIProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 617-619.South AfricaCathodluminescence, Carbon isotope, Deposit - Kaal Vallei
DS1995-1965
1995
Gurney, J.J.Van Heerden, L.A., Gurney, J.J., Deines, P.The carbon isotopic composition of harzburgite, lherzolite, websterite, eclogite paragenetic diamondsSouth. African Journal of Geology, Vol. 98, No. 2, June pp. 119-125.South Africa, BotswanaGeochronology -diamonds, Models -genetic
DS1995-2072
1995
Gurney, J.J.Woodborne, M.W., De Decker, R.H., Gurney, J.J., Smith, H.S.The marine geology of two mid water diamond concession areas off the Namaqualand coast... environments.Exploration and Mining Geology, Vol. 4, No. 1, p. 90-91.South AfricaMarine mining
DS1996-0232
1996
Gurney, J.J.Carlson, R.W., Grove, T.L., De Wit, M.J., Gurney, J.J.Program to study crust and mantle of the Archean craton in southernAfrica.Eos, Vol. 77, No. 29, July 16, pp. 273, 277.South AfricaKaapvaal Craton, Chemistry, geochemistry, geochronology, geodynamics
DS1996-0327
1996
Gurney, J.J.Daniels, L.R.M., Gurney, J.J., Harte, B.A crustal mineral in a mantle diamondNature, Vol. 379, No. 6561, Jan. 11, p. 153-GlobalDiamond Morphology, Deposit -
DS1996-0575
1996
Gurney, J.J.Gurney, J.J., Kirkley, M.B.Kimberlite dyke mining in South AfricaAfrica Geoscience Review, Vol. 3, No. 2, pp. 191-201.South AfricaDike complexes -Group II, Deposit -Bellsbank, Bobbejean, Ardo, Star, Rovic, HelaM.
DS1997-0264
1997
Gurney, J.J.Deines, P., Harris, J.W., Gurney, J.J.Carbon isotope ratios, nitrogen content and aggregation state, and inclusion chemistry of diamonds from JwanengGeochimica et Cosmochimica Acta, Vol. 61, No. 18, Sept. pp. 3993-4006.BotswanaMineralogy - diamond inclusions, Deposit - Jwaneng
DS1997-0500
1997
Gurney, J.J.Helmstaedt, H.H., Gurney, J.J.Geodynamic controls of kimberlites - what are the roles of hotspot and plate tectonics?Russian Geology and Geophysics, Vol. 38, No. 2, pp. 492-508.MantleHotspots, Plate tectonics
DS1997-0616
1997
Gurney, J.J.Kopylova, M.G., Gurney, J.J., Daniels, L.R.M.Mineral inclusions in diamonds from the River Ranch kimberlite, ZimbabweContributions to Mineralogy and Petrology, Vol. 129, No. 4, pp. 366-384.ZimbabweDiamond inclusions, Deposit - River Ranch
DS1997-0750
1997
Gurney, J.J.McCandless, T.E., Gurney, J.J.Diamond eclogites: comparison with carbonaceous chondrites, shales and microbial carbon enriched Mid Ocean Ridge Basalt (MORB).Russian Geology and Geophysics, Vol. 38, No. 2, pp. 394-404.MantleEclogites, Organic, carbon
DS1998-0249
1998
Gurney, J.J.Chinn, I.L., Gurney, J.J., Harte, B., FitzimmonsNitrogen contents of diamond plates: a comparison of FTIR and SIMSanalysis.7th International Kimberlite Conference Abstract, pp. 152-4.ColoradoDiamond morphology - nitrogen, Deposit - George Creek
DS1998-0251
1998
Gurney, J.J.Chinn, I.L., Milledge, H.J., Gurney, J.J.Diamonds and inclusions from the Jagersfontein kimberlite7th International Kimberlite Conference Abstract, pp. 156-7.South AfricaDiamond inclusions, Deposit - Jagersfontein
DS1998-0550
1998
Gurney, J.J.Gurney, J.J., Moore, R.O., Bell, D.R.Mineral associations and compositional evolution of Monastery kimberlitemegacrysts.7th International Kimberlite Conference Abstract, pp. 290-2.South AfricaPetrogenetic - Metasomatism, Deposit - Monastery
DS1998-0633
1998
Gurney, J.J.Hollick, P.C., Gurney, J.J.Contrasting styles of marine diamond mineralization requiring different mining methodologies - case study29th. Annual Underwater Mining Institute, 1p. abstractSouth AfricaMarine mining
DS1998-0771
1998
Gurney, J.J.Klump, J., Gurney, J.J.A pilot study of the Swartsruggens kimberlite dyke swarm7th International Kimberlite Conference Abstract, pp. 441-2.South AfricaPetrology, Deposit - Helam, Main Dyke, Changehouse, Muil
DS1998-0994
1998
Gurney, J.J.Menzies, A.H., Gurney, J.J., Harte, B., Hauri, E.rare earth elements (REE) patterns in diamond bearing eclogites and diamond bearing peridotites from Newlands kimberlite.7th International Kimberlite Conference Abstract, pp. 573-5.South AfricaEclogites, peridotites, Deposit - Newlands
DS1998-0995
1998
Gurney, J.J.Menzies, A.H., Milledge, H.J.M., Gurney, J.J.Fourier transform infra red (FTIR) spectroscopy of Newlands diamonds7th International Kimberlite Conference Abstract, pp. 576-8.South AfricaSpectroscopy, Deposit - Newlands
DS1998-0996
1998
Gurney, J.J.Menzies, A.H., Shirey, S.B., Carlson, R.W., Gurney, J.J.Re Os isotope systematics of diamond bearing eclogites and peridotites from New lands kimberlite.7th International Kimberlite Conference Abstract, pp. 579-1.South AfricaGeochronology, Deposit - Newlands
DS1998-1343
1998
Gurney, J.J.Shirey, S.B., Carlson, R.W., Gurney, J.J., Van HeerdenRe Os isotope systematics of eclogites from Roberts Victor: Implications for diamond growth ...7th International Kimberlite Conference Abstract, pp. 808-810.South AfricaArchean tectonic processes, geochronology, Deposit - Roberts Victor
DS1998-1596
1998
Gurney, J.J.Wyatt, B.A., Morfi, L., Gurney, J.J., Pearson, N.J.Garnets in a polymict xenolith from the Bultfontein Mine: new preliminary geochemical and textural data.7th International Kimberlite Conference Abstract, pp. 968-70.South AfricaPeridotite, mineral chemistry, Deposit - Bultfontein
DS1998-1623
1998
Gurney, J.J.Zartman, R.E., Richardson, S., Gurney, J.J., Moore, R.Uranium-thorium-lead ages of megacrystic zircon from the Monastery kimberlite, FreeState, South Africa.7th International Kimberlite Conference Abstract, pp. 989-91.South AfricaGeochronology, tectonics, Deposit - Monastery
DS1999-0471
1999
Gurney, J.J.Menzies, A.H., Carlson, R.W., Shirey, S.B., Gurney, J.J.Re Os systematics of Newlands peridotite xenoliths: implications for diamond lithosphere formation.7th International Kimberlite Conference Nixon, Vol. 2, pp. 566-73.South AfricaGeochronology, geothermometry, Deposit - Newlands
DS2000-0369
2000
Gurney, J.J.Gurney, J.J.Diamond indicator mineral interpretations: a discussion of some recent developments.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) 2000 Conference, 1p. abstractGlobalEclogites, Diamond inclusions
DS2000-0370
2000
Gurney, J.J.Gurney, J.J.The impact of geochemical research on kimberlite exploration for diamonds in the 20th. century and on...Geological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-4.GlobalGeochemistry - history
DS2001-0467
2001
Gurney, J.J.Helmstaedt, H., Gurney, J.J.Formation of the Archean Kaapvaal Province revisited: implications for birth and growth Diamondiferous rootSlave-Kaapvaal Workshop, Sept. Ottawa, 4p. abstractSouth AfricaCraton - Kaapvaal, Genesis
DS2001-1232
2001
Gurney, J.J.Westerlund, K., Gurney, J.J., Shirey, S.B., Hauri, E.Nitrogen aggregation and stable nitrogen and carbon isotope characteristics of diamonds from Panda.Slave-Kaapvaal Workshop, Sept. Ottawa, 4p. abstractNorthwest TerritoriesGeochronology, Deposit - Panda
DS2001-1300
2001
Gurney, J.J.Zhang, H., Menzies, M.A., Gurney, J.J., Zhou, X.Cratonic peridotites and silica rich melts, diopside enstatite relationships in polymict xenoliths, KaapvaalGeochimica et Cosmochimica Acta, Vol. 65, No. 19, pp. 3365-77.South AfricaGeochemistry - peridotites, Craton - Kaapvaal
DS2002-0033
2002
Gurney, J.J.Anckar, E.C., Gurney, J.J., Thiarz, C.A statistical approach to finger printing run of mine diamonds incorporating FTIR spectra, size distributions and physical characteristics.Eos, American Geophysical Union, Spring Abstract Volume, Vol.83,19, 1p.South AfricaDiamond - morphology, populations
DS2002-0703
2002
Gurney, J.J.Helmstaedt, H., Gurney, J.J.Hidden diamond deposits - role of tectonic and structural Craton analysis in integrated expl.approach.Society of Economic Geologists, Abstracts, pp. 27-28.Northwest TerritoriesTectonics - Slave Craton, Geodynamics
DS2003-0016
2003
Gurney, J.J.Anckar, E.C., Gurney, J.J., Thiart, C.A statistical approach to finger printing of run of mine diamonds using FTIR Spectra8 Ikc Www.venuewest.com/8ikc/program.htm, Session 3, AbstractGlobalDiamonds, database FTIR 495, Geostatistics - production
DS2003-0263
2003
Gurney, J.J.Coe, N.I.J., Le Roex, A.P., Gurney, J.J.The geochemistry of the Swartruggens and Star kimberlite dyke swarms, South Africa8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, POSTER abstractSouth AfricaDeposit - Swartruggens, Star
DS2003-0350
2003
Gurney, J.J.Doyle, P.M., Gurney, J.J., Le Roex, A.Xenoliths from the Arnie, Misery and Pigeon kimberlites8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractNorthwest TerritoriesMantle geochemistry, Deposit - Arnie, Misery, Pigeon
DS2003-0440
2003
Gurney, J.J.Garden , B.P., Carlson, R.W., Shirey, S.B., Gurney, J.J.RE OS systematics of lithospheric peridotites and eclogites from the Bobbejan and8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractSouth AfricaMantle geochemistry, Deposit - Bobbejan, Bellsbank, Jagersfontein
DS2003-0524
2003
Gurney, J.J.Gurney, J.J., Hildebrand, P., Carlson, J., Dyke, D., Fedortchouk, Y.Diamonds from the Ekati core and buffer zone properties8 Ikc Www.venuewest.com/8ikc/program.htm, Session 3, AbstractNorthwest TerritoriesDiamonds - inclusions, Deposit - Ekati
DS2003-0525
2003
Gurney, J.J.Gurney, J.J., Westerlund, K.J., Shirey, S.B., Carlson, R.W.Mineral compositions and Re Os isotope systematics of harzburgitic nodules from the8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractNorthwest TerritoriesMantle geochemistry, Deposit - Panda
DS2003-0526
2003
Gurney, J.J.Gurney, J.L., Baumgartner, M., Anckar, E., Gurney, J.J., Nowicki, T.E., GrutterKimberlite almanac8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractSouth AfricaDeposit - Finsch
DS2003-0625
2003
Gurney, J.J.Ivanic, T.J., Hartem B., Burgess, S.R., Gurney, J.J.Factors in the formation of sinuous and humped Ree patterns in garnets from mantle8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractMantleMantle geochemistry
DS2003-0916
2003
Gurney, J.J.McKenna, N., Gurney, J.J., Davidson, J.M.A study of diamonds, diamond inclusion minerals and other mantle minerals from the8 Ikc Www.venuewest.com/8ikc/program.htm, Session 3, AbstractSouth AfricaDiamonds - inclusions, database 115, Deposit - Swartruggens
DS2003-0938
2003
Gurney, J.J.Menzies, A.H., Carlson, R.W., Shirey, S.B., Gurney, J.J.Re Os systematics of diamond bearing eclogites from the Newlands kimberliteLithos, Vol. 71, 2-4, pp. 323-336.South AfricaGeochronology - deposit
DS2003-0939
2003
Gurney, J.J.Menzies, A.H., Frazenburg, M., Baumgartner, M.C., Gurney, J.J., Moore, R.O.Evaluation of chromites derived from kimberlites and implications for diamond8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractAustraliaBlank
DS2003-0940
2003
Gurney, J.J.Menzies, A.H., Westerlund, K., Gurney, J.J., Carlson, J., Fung, A., Nowicki, T.Peridotite mantle xenoliths from kimberlites on the Ekati property, Northwest8 Ikc Www.venuewest.com/8ikc/program.htm, Session 4, AbstractNorthwest TerritoriesMantle geochemistry, Deposit - Ekati
DS2003-1469
2003
Gurney, J.J.Westerlund, K.J., Hauri, E.H., Gurney, J.J.FTIR absorption and stable nitrogen and carbon isotope microanalysis of mid Archean8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractNorthwest TerritoriesDiamonds - inclusions, Deposit - Panda
DS2003-1470
2003
Gurney, J.J.Westerlund, K.J., Shirey, S.B., Richardson, S.H., Gurney, J.J., Harris, J.W.RE Os isotope systematics of peridotitic diamond inclusion sulfides from the Panda8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractNorthwest TerritoriesDiamonds - inclusions, Deposit - Panda
DS2003-1478
2003
Gurney, J.J.Williams, C., Van Coller, B., Nowicki, T., Gurney, J.J.Mega Kalahari geology: challenges of kimberlite exploration in this medium8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractSouth Africa, Democratic Republic of CongoKaapvaal Craton
DS200412-0032
2003
Gurney, J.J.Anckar, E.C., Gurney, J.J., Thiart, C.A statistical approach to finger printing of run of mine diamonds using FTIR Spectra, size distribution and physical characteris8 IKC Program, Session 3, AbstractTechnologyDiamonds, database FTIR 495 Geostatistics - production
DS200412-0340
2003
Gurney, J.J.Coe, N.I.J., Le Roex, A.P., Gurney, J.J.The geochemistry of the Swartruggens and Star kimberlite dyke swarms, South Africa.8 IKC Program, Session 7, POSTER abstractAfrica, South AfricaKimberlite petrogenesis
DS200412-0734
2004
Gurney, J.J.Grutter, H.S., Gurney, J.J., Menzies, A.H., Winter, F.An updated classification scheme for mantle derived garnet, for use by diamond explorers.Lithos, Vol. 77, 1-4, Sept. pp. 841-857.TechnologyExploration, pyrope, Ca intercept, peridotite, megacrys
DS200412-0752
2003
Gurney, J.J.Gurney, J.J., Hildebrand, P., Carlson, J., Dyke, D., Fedortchouk, Y.Diamonds from the Ekati core and buffer zone properties.8 IKC Program, Session 3, AbstractCanada, Northwest TerritoriesDiamonds - inclusions Deposit - Ekati
DS200412-0753
2004
Gurney, J.J.Gurney, J.J., Hildebrand, P.R., Carlson, J.A., Fedortchouk, Y., Dyck, D.R.The morphological characteristics of diamonds from the Ekati property, Northwest Territories, Canada.Lithos, Vol. 77, 1-4, Sept. pp. 21-38.Canada, Northwest TerritoriesDiamond morphology, colour
DS200412-0754
2003
Gurney, J.J.Gurney, J.L., Baumgartner, M., Anckar, E., Gurney, J.J., Nowicki, T.E., Grutter, H.S., Coetzee, M., Mason-JoneKimberlite almanac.8 IKC Program, Session 8, POSTER abstractAfrica, South AfricaDiamond exploration Deposit - Finsch
DS200412-1273
2003
Gurney, J.J.McKenna, N., Gurney, J.J., Davidson, J.M.A study of diamonds, diamond inclusion minerals and other mantle minerals from the Swartruggens kimberlite dyke swarm, South Afr8 IKC Program, Session 3, AbstractAfrica, South AfricaDiamonds - inclusions, database 115 Deposit - Swartruggens
DS200412-1274
2004
Gurney, J.J.McKenna, N., Gurney, J.J., Klump, J., Davidson, J.M.Aspects of diamond mineralization and distribution at the Helam mine, South Africa.Lithos, Vol. 77, 1-4, Sept. pp. 193-208.Africa, South AfricaSwartruggens dyke swarm, majorite, Type IaAB,Ib;eclogit
DS200412-1298
2004
Gurney, J.J.Menzies, A., Westerlund, K., Grutter, H., Gurney, J.J., Carlson, J., Fung, A., Nowicki, T.Peridotitic mantle xenoliths from kimberlites on the Ekati diamond mine property, NWT: major element compositions and implicatioLithos, Vol. 77, 1-4, Sept. pp. 395-412.Canada, Northwest TerritoriesSlave Craton, harzburgite, geothermometry, diamond grap
DS200412-1299
2003
Gurney, J.J.Menzies, A.H., Carlson, R.W., Shirey, S.B., Gurney, J.J.Re Os systematics of diamond bearing eclogites from the Newlands kimberlite.Lithos, Vol. 71, 2-4, pp. 323-336.Africa, South AfricaGeochronology - deposit
DS200412-1300
2003
Gurney, J.J.Menzies, A.H., Frazenburg, M., Baumgartner, M.C., Gurney, J.J., Moore, R.O.Evaluation of chromites derived from kimberlites and implications for diamond exploration programs.8 IKC Program, Session 8, POSTER abstractAustraliaDiamond exploration
DS200412-1301
2003
Gurney, J.J.Menzies, A.H., Westerlund, K., Gurney, J.J., Carlson, J., Fung, A., Nowicki, T.Peridotite mantle xenoliths from kimberlites on the Ekati property, Northwest Territories, Canada.8 IKC Program, Session 4, AbstractCanada, Northwest TerritoriesMantle geochemistry Deposit - Ekati
DS200412-2034
2003
Gurney, J.J.Van Coller, B., Hildenbrand, P., Verran, D., Barnes, F., Nowicki, T.E., Baumgartner, M., Ott, L., Gurney, J.J.Southern African case studies of variations in indicator mineral characteristics with distance from kimberlite source.8 IKC Program, Session 8, POSTER abstractAfrica, South AfricaDiamond exploration
DS200412-2103
2004
Gurney, J.J.Westerlund, K.J., Gurney, J.J.Silicate and oxide inclusion characteristics and infra red absorption analysis of diamonds from the Klipspringer kimberlites, SoSouth African Journal of Geology, Vol. 107, 1/2, pp. 131-146.Africa, South AfricaDeposit - Klipspringer, diamond inclusions
DS200412-2104
2004
Gurney, J.J.Westerlund, K.J., Gurney, J.J., Carlson, R.W., Shirey, S.B., Hauri, E.H., Richardson, S.H.A metasomatic origin for late Archean eclogitic diamonds: implications from internal morphology of diamonds and Re Os and S isotSouth African Journal of Geology, Vol. 107, 1/2, pp. 119-130.Africa, South AfricaDeposit - Klipspringer, Jurassic, sulfide inclusions
DS200412-2115
2003
Gurney, J.J.Williams, C., Van Coller, B., Nowicki, T., Gurney, J.J.Mega Kalahari geology: challenges of kimberlite exploration in this medium.8 IKC Program, Session 8, POSTER abstractAfrica, South Africa, Democratic Republic of CongoDiamond exploration Kaapvaal Craton
DS200512-0383
2005
Gurney, J.J.Gurney, J.J.A view on the contribution of Herb Helmstaedt to craton evolution over four decades.GAC Annual Meeting Halifax May 15-19, Abstract 1p.MantleAccretion, emplacement, kimberlites, diamond genesis
DS200612-1522
2006
Gurney, J.J.Westerlund, K.J., Shirey, S.B., Richardson, S.H., Carlson, R.W., Gurney, J.J., Harris, J.W.A subduction wedge origin for Paleoarchean peridotitic diamonds and harzburgites from the PAnd a kimberlite, Slave Craton: evidence from Re Os isotope systematics.Contributions to Mineralogy and Petrology, Vol. 152, 3, pp. 275-294.Canada, Northwest TerritoriesSubduction, deposit - Panda
DS200712-0783
2007
Gurney, J.J.Nowicki, T.E., Moore, R.O., Gurney, J.J., Baumgartner, M.C.Diamonds and associated heavy minerals in kimberlite: a review of key concepts and applications.Developments in Sedimentology, Vol. 58, pp. 1235-1267.TechnologyGeochemistry - indicator minerals
DS200912-0296
2009
Gurney, J.J.Helmsteadt, H.H., Gurney, J.J., Richardson, S.H.Diamond ages and lithosphere evolution: applications to diamond exploration.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyTechnologyDiamond genesis and craton evolution
DS201012-0254
2010
Gurney, J.J.Gurney, J.J., Helmstaedt, H.H., Richardson, S.H., Shirey, S.B.Diamonds through time.Economic Geology, Vol. 105, 3, pp. 689-712.GlobalHistory of diamond genesis
DS201012-0725
2010
Gurney, J.J.Smit, K.V., Shirey, S.B., Richardson, S.H., Le Roex, A.P., Gurney, J.J.Re-Os isotopic composition of peridotitic sulphide inclusions in diamonds from Ellendale, Australia: age constraints on Kimberley cratonic lithosphere.Geochimica et Cosmochimica Acta, Vol. 74, 11, pp. 3292-3306.AustraliaDeposit - Ellendale
DS201112-0429
2010
Gurney, J.J.Helmstaedt, H.H., Gurney, J.J., Richardson, S.H.Ages of cratonic diamond and lithosphere evolution: constraints on Precambrian tectonics and diamond exploration.The Canadian Mineralogist, Vol. 48, 6, pp. 1385-1408.Canada, GlobalGeochronology, craton roots, UHP
DS201212-0274
2012
Gurney, J.J.Gurney, J.J., Helmstaedt, H.H.Type Iia diamonds and their enhanced ecnomic significance.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractGlobalDiamond - Iia
DS201212-0334
2012
Gurney, J.J.Ivanic, T.J., Harte, B., Gurney, J.J.Metamorphic re-equilibrium and metasomatism of highly chromian, garnet-rich peridotitic xenoliths from South Africa kimberlites.Contributions to Mineralogy and Petrology, in press available 16p.Africa, South AfricaDeposit - Newlands, Bobbejaan
DS201412-0327
2014
Gurney, J.J.Gurney, J.J., Kahle, R., Kahle, B., Richardson, S.H., du Plessis, A.X-ray Cat scanning of Diamondiferous mantle xenoliths.GSSA Kimberley Diamond Symposium and Trade Show provisional programme, Sept. 12, title onlyTechnologyX-Ray scanning
DS201412-0343
2014
Gurney, J.J.Harte, B., Dawson, J.B., Gurney, J.J.Field counts of mantle xenoliths from the Kaapvaal Craton: with memories of Barry Dawson.Volcanic and Magmatic Studies Group meeting, Abstract only Held Jan. 6-8. See minsoc websiteAfrica, South AfricaXenoliths
DS201512-1944
1994
Gurney, J.J.McCandless, T.E., Waldman, M.A., Gurney, J.J.Macro- and microdiamonds from Arkansas lamproites: morphology, inclusions and isotope geochemistry.Proceedings of the 5th. International Kimberlite Conference, Vol. 2, pp. 78-97.United States, ArkansasMicrodiamonds

Abstract: The first report of diamond in igneous rock in the United States originated at Prairie Creek, Arkansas. We have examined the morphological, carbon isotope, and inclusion characteristics of diamonds from Prairie Creek, and from the Twin Knobs # 1, #2, Black Lick, and American lamproites. White is the most common macrodiamond color at Prairie Creek (62% of total), with 20% brown and 16% yellow. This contrasts with Australian lamproites where brown predominates, and with other North American localities such as the Sloan, Colorado kimberlites where yellow is rare. Lamination lines indicate ductile deformation at mantle conditions. The macrodiamonds are very resorbed; 82% are equiform or distorted tetrahexahedroida and none are octahedra. Low relief surfaces indicate prolonged and/or intense resorption. Microdiamonds differ dramatically, with octahedra and fragn~ents common and tetrahexahedroida abscnL Serrate laminae, knob-like asperities, pointed plates, ribbing, and non-uniform resorption are the most common surface features. Diamonds from the Twin Knobs # 1 lamproite are similar to microdiamonds with respect to size and surface features. Magnetite and olivine (F093) are the only primary inclusions foqnd in the diamonds, although inclusions of peridotitic and eclogitic parageneses have been reported in previous studies. Carbon isotope B13c values for Prairie Creek macrodiamonds peak at-3.0 to -6.2 %o (ave. -4.7 %o for 19 stones) and -10.3 to -10.6 %o (ave. -10.5 %o for 2 stones). The diamonds with magnetite and olivine inclusions have B13c values of -5.1 %o and -4.0 %o respectively. Microdiamonds from Prairie Creek, Twin Knobs #2, American, and Black Lick are similar to Prairie Creek macrodiamonds ( -0.5 to -7 .8; ave. -4.1 %o for 8 stones). A Prairie Creek and a Black Lick microdiamond have B13c values of -26.1 and -25.2%orespectively, and the latter exhibits non-uniform resorption. Lamination lines on macrodiamonds and xenocrystic surface features on microdiamonds imply that both are xenocrysts in lamproite. Carbon isotopes are characteristic of a peridotitic or primordial carbon reservoir. Two 13cdepleted microdiamonds may be from a subducted carbon source. In comparison to macrodiamond populations from most kimberlites, Prairie Creek macrodiamonds are intensely resorbed, and lamproite may be more corrosive than kimberlite \\ ith respect to diamond resorption. Microdiamonds were probably encapsulated in xenolith material ani.! esca•,)ed resorption. The differences in size and color of Prairie Creek macrodiamonds relative to Sloan kimberlitic diamonds are genetic, and may be related to their formation in lithosphere of differing age and tectonic history.
DS201603-0387
2016
Gurney, J.J.Ivanic, T.J., Harte, B., Gurney, J.J.A discussion of "Mineralogical controls on garnet composition in the cratonic mantle" by Hill et al. 2015Contributions to Mineralogy and Petrology, Vol. 171, 4p.MantleMineralogy
DS201603-0417
2016
Gurney, J.J.Riches, A.J.V., Ickert, R.B., Pearson, D.G., Stern, R.A., Jackson, S.E., Ishikawa, A., Kjarsgaard, B.A., Gurney, J.J.In situ oxygen-isotope, major, and trace element constraints on the metasomatic modification and crust origin of a Diamondiferous eclogite from Roberts Victor, Kaapvaal craton.Geochimica et Cosmochimica Acta, Vol. 174, pp. 345-359.Africa, South AfricaDeposit - Roberts Victor
DS201708-1661
2017
Gurney, J.J.Gurney, J.J.Multiple phases of mantle metasomatism revealed by x-ray CT scanning of southern african Diamondiferous eclogites.11th. International Kimberlite Conference, OralAfrica, Southen Africametasomatism

Abstract: In this study, a private collection of diamondiferous eclogite xenoliths has been made available for non-destructive investigation. All samples have at least one diamond visible. The samples are predominantly sourced from the Excelsior and Newlands mines (South Africa), with additional samples from Roberts Victor mine (South Africa) and Orapa (Botswana). 3D volume models of the samples were created using X-ray tomography. The 3D images reveal abundant secondary veining that is clearly younger than the eclogite. Diamonds are located in fluid pathways and occur in both altered garnet and altered clinopyroxene. Most of the veining is unrelated to the spatial positioning of diamond in the samples. In some instances, early veining has annealed or partially annealed, suggesting a range in timing of at least some of the several metasomatic events that have affected the rock. Importantly, in the most graphic examples, a clear distinction can be seen between diamond-bearing and non-diamond-bearing veins, even where sulphide is present in abundance in the non-diamond-bearing veins. The amount of diamond detected in the xenoliths varies from a single crystal to well over 50 diamonds forming more than 9% of the rock. This extreme value contrasts with the diamond recovery from currently viable diamond mines of less than 2ppm or 0.0002%. The morphology of the diamonds includes step-faced flat-faced octahedra, single crystals and aggregates. This is particularly a feature of diamonds in the Excelsior specimens. In the samples from Newlands and Orapa, in contrast, diamond surfaces reflect resorption processes such as rounding and corrosion of the diamonds. The following conclusions can be drawn from this study: Diamonds in this collection, sourced from within the Kalahari craton, appear to have formed by a metasomatic process during which fluids infiltrated pre-existing mantle-derived eclogite; Several metasomatic events have occurred during the residence of the eclogite in the mantle; Some of these metasomatic events have been diamond-friendly, whilst others have been diamond-neutral or diamond-destructive; Diamond can be present at very high concentrations along particular metasomatic fluid pathways in eclogitic mantle rocks; The absolute timing of diamond formation is still to be determined.
DS201804-0723
2018
Gurney, J.J.Nestola, F., Korolev, N., Kopylova, M., Rotiroti, N., Pearson, D.G., Pamato, M.G., Alvaro, M., Peruzzo, L., Gurney, J.J., Moore, A.E., Davidson, J.CaSiO3 perovskite in diamond indicates the recycling of oceanic crust into the lower mantle.Nature, Vol. 555, March 8, pp. 237-241.Mantledeposit - Cullinan

Abstract: Laboratory experiments and seismology data have created a clear theoretical picture of the most abundant minerals that comprise the deeper parts of the Earth’s mantle. Discoveries of some of these minerals in ‘super-deep’ diamonds—formed between two hundred and about one thousand kilometres into the lower mantle—have confirmed part of this picture1,2,3,4,5. A notable exception is the high-pressure perovskite-structured polymorph of calcium silicate (CaSiO3). This mineral—expected to be the fourth most abundant in the Earth—has not previously been found in nature. Being the dominant host for calcium and, owing to its accommodating crystal structure, the major sink for heat-producing elements (potassium, uranium and thorium) in the transition zone and lower mantle, it is critical to establish its presence. Here we report the discovery of the perovskite-structured polymorph of CaSiO3 in a diamond from South African Cullinan kimberlite. The mineral is intergrown with about six per cent calcium titanate (CaTiO3). The titanium-rich composition of this inclusion indicates a bulk composition consistent with derivation from basaltic oceanic crust subducted to pressures equivalent to those present at the depths of the uppermost lower mantle. The relatively ‘heavy’ carbon isotopic composition of the surrounding diamond, together with the pristine high-pressure CaSiO3 structure, provides evidence for the recycling of oceanic crust and surficial carbon to lower-mantle depths.https://www.nature.com/articles/nature25972
DS201808-1760
2018
Gurney, J.J.Korolev, N., Kopylova, M., Gurney, J.J., Moore, A.E., Davidson, J.The origin of Type II diamonds as inferred from Culli nan mineral inclusions.Mineralogy and Petrology, doi.org/10.1007/s710-018-0601-z 15p. Africa, South Africadeposit - Cullinan

Abstract: We studied a suite of Cullinan diamonds (<0.3 ct) with mineral inclusions, which comprised 266 Type I and 75 blank Type II (<20 ppm N) diamonds, as classified by infrared spectroscopy. More than 90% (n?=?68) of Type II diamonds do not luminesce. In contrast, 51.9% (n?=?177) of Type I diamonds luminesce, with blue colors of different intensity. Carbon isotopic compositions of Type I and II diamonds are similar, with ?13CVPDB ranging from ?2.1 to ?7.7‰for Type I diamonds (n?=?25), and from ?1.3 to ?7.8- for Type II diamonds (n?=?20). The Type II diamonds are sourced from three parageneses, lithospheric lherzolitic (45%), lithospheric eclogitic (33%), and sublithospheric mafic (22%). The lherzolitic suite contains Cr-pyrope, forsterite, enstatite, clinopyroxene and Cr-spinel formed at 1090-1530 °C and P?=?4.6-7.0 GPa. Lithospheric eclogitic diamonds containing garnet, omphacite, kyanite and coesite comprise 33% of Type II diamonds. The sublithospheric mafic paragenesis is mainly represented by Cr-free majorite, various CaSiO3 phases and omphacite equilibrated at 11.6-26 GPa, in the transition zone and the lower mantle. The lherzolitic paragenesis predominates in Type II diamonds, whereas 79% Type I diamonds are sourced from eclogites. The higher incidence of sublithospheric inclusions was found in Type II diamonds, 22% against 6% in Type I diamonds. The similarity of the mineral parageneses and C isotopic compositions in the small Cullinan Type II and Type I diamonds indicate the absence of distinct mantle processes and carbon sources for formation of studied Type II diamonds. The parent rocks and the carbon sources generally vary for Type II diamonds within a kimberlite and between kimberlites.
DS1995-0706
1995
Gurney, J.L.Gurney, J.L., Gurney, J.J.Garnet and ilmenite from some Premier kimberlite intrusivesProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 211-13.South AfricaPetrology, Deposit -Premier
DS2003-0526
2003
Gurney, J.L.Gurney, J.L., Baumgartner, M., Anckar, E., Gurney, J.J., Nowicki, T.E., GrutterKimberlite almanac8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractSouth AfricaDeposit - Finsch
DS200412-0754
2003
Gurney, J.L.Gurney, J.L., Baumgartner, M., Anckar, E., Gurney, J.J., Nowicki, T.E., Grutter, H.S., Coetzee, M., Mason-JoneKimberlite almanac.8 IKC Program, Session 8, POSTER abstractAfrica, South AfricaDiamond exploration Deposit - Finsch
DS1990-0625
1990
Gurnis, M.Gurnis, M.Plate mantle coupling and continental floodingGeophysical Research Letters, Vol. 17, No. 5, April pp. 623-626GlobalMantle, Plate tectonics -flooding
DS1990-0626
1990
Gurnis, M.Gurnis, M.Bounds on global dynamic topography from Phanerozoic flooding of continental platformsNature, Vol. 344, No. 6268, April 19, pp. 754-756GlobalPhanerozoic, Continental flooding, Mantle
DS1990-0627
1990
Gurnis, M.Gurnis, M.Plate mantle coupling and continental floodingGeophysical Research Letters, Vol. 17, No. 5, Apr. pp. 623-6.MantleTectonics - coupling, subduction
DS1992-0639
1992
Gurnis, M.Gurnis, M.Long term controls on eustatic and epeirogenic motions by mantleconvectionGsa Today, Vol. 2, No. 7, July pp. 142, 144, 145, 156, 157GlobalMantle, Geodynamics
DS1993-0601
1993
Gurnis, M.Gurnis, M.Phanerozoic marine in undation of continents driven by dynamic topography above subducting slabsNature, Vol. 364, No. 6438, August 12, pp. 589-592MantleTectonics, Subduction -Phanerozoic
DS1993-0602
1993
Gurnis, M.Gurnis, M., Russell, M., Coakley, B.J.Phanerozoic marine in undation and tilting of continents driven by dynamic subsidence above slabsGeological Society of America Annual Abstract Volume, Vol. 25, No. 6, p. A197 abstract onlyMantleSubduction, Slabs
DS1994-0683
1994
Gurnis, M.Gurnis, M., Torsvik, T.H.Rapid drift of large continents during the late Precambrian and Paleozoic:paleomagnetic constraints.Geology, Vol. 22, No. 11, November pp. 1023-1026.Laurentia, Baltic StatesGeodynamics, Polar wandering
DS1994-1502
1994
Gurnis, M.Russell, M., Gurnis, M.The planform of epeirogeny: vertical motions of Australia during theCretaceousBasin Research, Vol. 6, No. 2-3, June/Sept. pp. 63-76AustraliaTectonics, Epeirogeny, eustasy
DS1995-0235
1995
Gurnis, M.Burgess, P.M., Gurnis, M., Moresi, L.N.Geodynamical contributions to the formation of North American cratonic stratigraphic sequences.Eos, Vol. 76, No. 46, Nov. 7. p.F535. Abstract.United States, Canada, North AmericaCraton, Geodynamics
DS1995-0331
1995
Gurnis, M.Coakley, B., Gurnis, M.Far field tilting of Laurentia -Ordovician and constraints on evolution slab under ancient continent.Journal of Geophysical Research, Vol. 100, No. B4, April 10, pp. 6313-27.Wisconsin, Michigan, AppalachiaSlab, Mantle convection
DS1995-2137
1995
Gurnis, M.Zhang, S., Gurnis, M.Mantle convection with plates and mobile faulted plate marginsScience, Vol. 267, No. 5199, Feb. 10, pp. 838-842.MantleTectonics -plate margins
DS1996-0992
1996
Gurnis, M.Moresi, L., Gurnis, M.Constraints on the lateral strength of slabs from three dimensional dynamic flow models.Earth and Planetary Science Letters, Vol. 138, No. 1/4, Feb. 1, pp. 15-28.MantleSubduction, Slab -flow models
DS1997-0145
1997
Gurnis, M.Burgess, P.M., Gurnis, M., Moresi, L.N.Formation of sequences in the cratonic interior of North America by interaction between mantle, eustatic..Geological Society of America (GSA) Bulletin., Vol. 109, No. 12, Dec. pp. 1515-1535.North America, United States, Canada, Alberta, MontanaCraton, Stratigraphy, geochronology
DS1997-0684
1997
Gurnis, M.Lithgow-Bertelloni, C., Gurnis, M.Cenozoic subsidence and uplift of continents from time varying dynamictopographyGeology, Vol. 25, No. 8, August pp. 735-738MantleKula plate, Subduction
DS1997-0685
1997
Gurnis, M.Lithgow-Bertelloni, C., Gurnis, M.Cenozoic subsidence and uplift of continents from time-varying dynamictopography.Geology, Vol. 25, No. 8, August pp. 735-738.United States, Canada, India, Australia, IndonesiaTomography, Subduction
DS1998-1345
1998
Gurnis, M.Sidorin, I., Gurnis, M., Helmberger, D.V., Ding, X.Interpreting D seismic structure using synthetic waveforms computed from dynamic models.Earth and Planetary Science Letters, Vol. 163, No. 1-4, Nov. pp. 31-41.MantleGeophysics - seismic, Slab
DS1998-1638
1998
Gurnis, M.Zhong, S., Gurnis, M., Moresi, L.Role of faults, nonlinear rheology, and viscosity structure in generating plates from instant... mantle.Journal of Geophysical Research, Vol. 103, No. 7, Jul. 10, pp. 15255-68.MantleMantle flow models, Tectonics
DS1999-0507
1999
Gurnis, M.NI, S., Ding, X., Gurnis, M.Low viscosity structure beneath Africa from forward modelingEarth and Planetary Science Letters, Vol. 170, No. 4, July 30, pp. 497-AfricaGeophysics - seismics, Tectonics - structure
DS1999-0666
1999
Gurnis, M.Sidorin, I., Gurnis, M., Hlemberger, D.V.Dynamics of a phase change at the base of the mantle consistent with seimological observations.Journal of Geophysical Research, Vol. 104, No. 7, July 10, pp. 15005-22.MantleGeophysics - seismics
DS2000-0371
2000
Gurnis, M.Gurnis, M., Mitrovica, J.X.Mantle convection, seismic tomography and the geological record: constraining the density structure of the African Superplume.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Calgary May 2000, 1p.AfricaMantle model - superplume
DS2000-0372
2000
Gurnis, M.Gurnis, M., Ritsema, J., Zhong, S.Tonga slab deformation: the influence of a lower mantle upwelling on a slab in a young subduction zone.Geophysical Research Letters, Vol. 27, No. 16, Aug. 15, pp.2373-6.MantleSubduction
DS2003-0532
2003
Gurnis, M.Hall, C.E., Gurnis, M., Sdrolias, M., Lavier, L., Muller, R.D.Catastrophic initiation of subduction following forced convergence across fractureEarth and Planetary Science Letters, Vol. 212, 1-2, pp. 15-30.MantleBlank
DS200412-0755
2004
Gurnis, M.Gurnis, M., Muller, R.D.Origin of the Australian Antarctic discordance from an ancient slab and mantle wedge.Hillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological Society America Memoir, No. 372, pp. 417-430.AustraliaSubduction
DS200412-0762
2003
Gurnis, M.Hall, C.E., Gurnis, M., Sdrolias, M., Lavier, L., Muller, R.D.Catastrophic initiation of subduction following forced convergence across fracture zones.Earth and Planetary Science Letters, Vol. 212, 1-2, pp. 15-30.MantleTectonics
DS200612-0563
2005
Gurnis, M.Helmberger, D., Lay, T., Ni, S., Gurnis, M.Deep mantle structure and the postperovskite phase transition.Proceedings of National Academy of Science USA, Vol. 102, no. 48, pp. 17257-283,MantleTectonics
DS200612-1407
2005
Gurnis, M.Tan, E., Gurnis, M.Metastable superplumes and mantle compressibility.Geophysical Research Letters, Vol. 32, 20, Oct. 28, L20307MantlePlume, hotspots
DS200712-0678
2007
Gurnis, M.Manea, V., Gurnis, M.Subduction zone evolution and low viscosity wedges and channels.Earth and Planetary Science Letters, Vol. 264, 1-2, pp. 22-45.MantleSubduction
DS200712-1051
2007
Gurnis, M.Sun, D., Tan, E., Helmberger, D., Gurnis, M.Seismological support for the metastable superplume model, sharp features, and phase changes within the lower mantle.Proceedings of National Academy of Sciences USA, Vol. 104, 22, pp. 9151-9155. IngentaMantleGeophysics - seismics
DS200712-1066
2007
Gurnis, M.Tan, E., Gurnis, M.Compressible thermochemical convection and application to lower mantle structures.Journal of Geophysical Research, Vol. 112, B6, B06304.MantleGeothermometry
DS200812-0675
2008
Gurnis, M.Liu, L., Gurnis, M.Simultaneous inversion of mantle properties and initial conditions using an adjoint of mantle convection.Journal of Geophysical Research, Vol. 113, B8405MantleConvection
DS200812-0676
2008
Gurnis, M.Liu, L., Gurnis, M.Simultanaeous inversion of mantle properties and initial conditions using an adjoint of mantle convection.Journal of Geophysical Research, Vol. 113, B8, B80405.MantleConvection
DS200812-0677
2008
Gurnis, M.Liu, L., Spasojevi, S., Gurnis, M.Reconstructing Farallon plate subduction beneath North America back to the late Cretaceous.Science, Vol. 322, 5903, Nov. 7, pp. 934-937.United States, CanadaSubduction
DS200912-0186
2009
Gurnis, M.Downey, N.J., Gurnis, M.Instantaneous dynamics of the cratonic Congo basin.Journal of Geophysical Research, Vol. 114, B06401AfricaGeodynamics
DS200912-0291
2009
Gurnis, M.Hebert, L.B., Antoshechkina, P., Asimow, P., Gurnis, M.Emergence of low viscosity channel in subduction zones through the coupling of mantle flow and thermodynamics.Earth and Planetary Interiors, Vol. 278, 3-4, pp. 243-256.MantleSubduction
DS200912-0293
2009
Gurnis, M.Helmberger, D., Sun, D., Lui, L., Tan, E., Gurnis, M.Review of large low shear veolocity provinces in the lower mantle.Goldschmidt Conference 2009, p. A520 Abstract.MantleCMB
DS201012-0793
2010
Gurnis, M.Torsvik, T.H., Steinberger, B., Gurnis, M., Gaina, C.Plate tectonics and net lithosphere rotation over the past 150 My.Earth and Planetary Science Letters, Vol. 291, 1-4, pp. 106-112.MantleTectonics
DS201212-0012
2012
Gurnis, M.Alistic, L., Gurnis, M., Stadler, G., Burstedde, C., Ghattas, O.Multi scale dynamics and rheology of mantle flow with plates.Journal of Geophysical Research, Vol. 117, B10 B10402MantleTectonics
DS201312-0113
2013
Gurnis, M.Burstedde, C., Stadler,G., Alisic, L., Wilcox, L.C., Tan, E.,Gurnis, M., Ghattas, O.Large scale adaptive mantle convection simulation.Geophysical Journal International, Vol. 192, no. 3, pp. 889-906.MantleConvection
DS201312-0376
2013
Gurnis, M.Helmberger, D., Chu, R., Leng, W., Gurnis, M.Hidden hotspot track beneath eastern United States.Goldschmidt 2013, AbstractUnited States, KentuckyKimberlite
DS201412-0084
2014
Gurnis, M.Burkett, E., Gurnis, M.Stalled slab dynamics.Lithosphere, Vol. 6, no. 1, pp. 92-97.MantlePlume
DS201508-0357
2015
Gurnis, M.Hassan, R., Flament, N., Gurnis, M., Bower, D.J., Muller, D.Provenance of plumes in global convection models.Geochemistry, Geophysics, Geosystems: G3, Vol. 16, 5m pp. 1465-1489.AfricaConvection
DS201612-2301
2016
Gurnis, M.Hassan, R., Muller, R.D., Gurnis, M., Williams, S.E., Flament, N.A rapid burst in hotspot motion through the interaction of tectonics and deep mantle flow.Nature, Vol. 533, pp. 239-242.MantleHotspots

Abstract: Volcanic hotspot tracks featuring linear progressions in the age of volcanism are typical surface expressions of plate tectonic movement on top of narrow plumes of hot material within Earth’s mantle1. Seismic imaging reveals that these plumes can be of deep origin2=probably rooted on thermochemical structures in the lower mantle3, 4, 5, 6. Although palaeomagnetic and radiometric age data suggest that mantle flow can advect plume conduits laterally7, 8, the flow dynamics underlying the formation of the sharp bend occurring only in the Hawaiian-Emperor hotspot track in the Pacific Ocean remains enigmatic. Here we present palaeogeographically constrained numerical models of thermochemical convection and demonstrate that flow in the deep lower mantle under the north Pacific was anomalously vigorous between 100 million years ago and 50 million years ago as a consequence of long-lasting subduction systems, unlike those in the south Pacific. These models show a sharp bend in the Hawaiian-Emperor hotspot track arising from the interplay of plume tilt and the lateral advection of plume sources. The different trajectories of the Hawaiian and Louisville hotspot tracks arise from asymmetric deformation of thermochemical structures under the Pacific between 100 million years ago and 50 million years ago. This asymmetric deformation waned just before the Hawaiian-Emperor bend developed, owing to flow in the deepest lower mantle associated with slab descent in the north and south Pacific.
DS201707-1333
2016
Gurnis, M.Hassan, R., Muller, R.D., Gurnis, M., Williams, S.E., Flament, N.A rapid burst in hotspot motion through the interaction of tectonics and deep mantle flow.Nature Geoscience, Vol. 533, 7603, pp. 239-242.Mantleplumes

Abstract: Volcanic hotspot tracks featuring linear progressions in the age of volcanism are typical surface expressions of plate tectonic movement on top of narrow plumes of hot material within Earth’s mantle1. Seismic imaging reveals that these plumes can be of deep origin2—probably rooted on thermochemical structures in the lower mantle3, 4, 5, 6. Although palaeomagnetic and radiometric age data suggest that mantle flow can advect plume conduits laterally7, 8, the flow dynamics underlying the formation of the sharp bend occurring only in the Hawaiian–Emperor hotspot track in the Pacific Ocean remains enigmatic. Here we present palaeogeographically constrained numerical models of thermochemical convection and demonstrate that flow in the deep lower mantle under the north Pacific was anomalously vigorous between 100 million years ago and 50 million years ago as a consequence of long-lasting subduction systems, unlike those in the south Pacific. These models show a sharp bend in the Hawaiian–Emperor hotspot track arising from the interplay of plume tilt and the lateral advection of plume sources. The different trajectories of the Hawaiian and Louisville hotspot tracks arise from asymmetric deformation of thermochemical structures under the Pacific between 100 million years ago and 50 million years ago. This asymmetric deformation waned just before the Hawaiian–Emperor bend developed, owing to flow in the deepest lower mantle associated with slab descent in the north and south Pacific.
DS201906-1327
2019
Gurnis, M.Muller, R.D., Zahirovic, S., Williams, S.E., Cannon, J., Seton, M., Bower, D.J., Tetley, M., Heine, C., Le Breton, E., Liu, S., Russell, S.H.J., Yang, T., Leonard, J., Gurnis, M.A global plate model including lithospheric deformation along major rifts and orogens since the Triassic.Tectonics, May 5, 36p. Mantleplate tectonics

Abstract: Global deep?time plate motion models have traditionally followed a classical rigid plate approach, even though plate deformation is known to be significant. Here we present a global Mesozoic?Cenozoic deforming plate motion model that captures the progressive extension of all continental margins since the initiation of rifting within Pangea at ~240 Ma. The model also includes major failed continental rifts and compressional deformation along collision zones. The outlines and timing of regional deformation episodes are reconstructed from a wealth of published regional tectonic models and associated geological and geophysical data. We reconstruct absolute plate motions in a mantle reference frame with a joint global inversion using hotspot tracks for the last 80 million years and minimizing global trench migration velocities and net lithospheric rotation. In our optimized model net rotation is consistently below 0.2°/Myr, and trench migration scatter is substantially reduced. Distributed plate deformation reaches a Mesozoic peak of 30 million km2 in the Late Jurassic (~160?155 Ma), driven by a vast network of rift systems. After a mid?Cretaceous drop in deformation it reaches a high of 48 million km2 in the Late Eocene (~35 Ma), driven by the progressive growth of plate collisions and the formation of new rift systems. About a third of the continental crustal area has been deformed since 240 Ma, partitioned roughly into 65% extension and 35% compression. This community plate model provides a framework for building detailed regional deforming plate networks and form a constraint for models of basin evolution and the plate?mantle system.
DS201907-1562
2019
Gurnis, M.Muller, D., Zahirovic, S., Williams, S.E., Cannon, J., Seton, M., Bower, D.J., Tetley, M., Heine, C., Le Breton, E., Liu, S., Russell, S.H.J., Yang, T., Leonard, J., Gurnis, M.A global plate model including lithospheric deformation along major rifts and orogens since the Triassic.Tectonics, in press available, 37p.Africa, globalplate tectonics, rotation

Abstract: Global deep?time plate motion models have traditionally followed a classical rigid plate approach, even though plate deformation is known to be significant. Here we present a global Mesozoic-Cenozoic deforming plate motion model that captures the progressive extension of all continental margins since the initiation of rifting within Pangea at ~240 Ma. The model also includes major failed continental rifts and compressional deformation along collision zones. The outlines and timing of regional deformation episodes are reconstructed from a wealth of published regional tectonic models and associated geological and geophysical data. We reconstruct absolute plate motions in a mantle reference frame with a joint global inversion using hot spot tracks for the last 80 million years and minimizing global trench migration velocities and net lithospheric rotation. In our optimized model, net rotation is consistently below 0.2°/Myr, and trench migration scatter is substantially reduced. Distributed plate deformation reaches a Mesozoic peak of 30 × 106 km2 in the Late Jurassic (~160-155 Ma), driven by a vast network of rift systems. After a mid?Cretaceous drop in deformation, it reaches a high of 48 x 106 km2 in the Late Eocene (~35 Ma), driven by the progressive growth of plate collisions and the formation of new rift systems. About a third of the continental crustal area has been deformed since 240 Ma, partitioned roughly into 65% extension and 35% compression. This community plate model provides a framework for building detailed regional deforming plate networks and form a constraint for models of basin evolution and the plate?mantle system.
DS202005-0764
2019
Gurnis, M.Tetley, M.G., Williams, S.E., Gurnis, M., Flament, N., Muller, R.D.Constraining absolute plate motions since the Triassic.Journal of Geophysical Research Solid Earth, 10.1029/2019JB0 17442 28p. PdfGlobalgeodynamics

Abstract: The absolute motion of tectonic plates since Pangea can be derived from observations of hotspot trails, paleomagnetism, or seismic tomography. However, fitting observations is typically carried out in isolation without consideration for the fit to unused data or whether the resulting plate motions are geodynamically plausible. Through the joint evaluation of global hotspot track observations (for times <80 Ma), first?order estimates of net lithospheric rotation (NLR), and parameter estimation for paleo-trench migration (TM), we present a suite of geodynamically consistent, data?optimized global absolute reference frames from 220 Ma to the present. Each absolute plate motion (APM) model was evaluated against six published APM models, together incorporating the full range of primary data constraints. Model performance for published and new models was quantified through a standard statistical analyses using three key diagnostic global metrics: root?mean square plate velocities, NLR characteristics, and TM behavior. Additionally, models were assessed for consistency with published global paleomagnetic data and for ages <80 Ma for predicted relative hotspot motion, track geometry, and time dependence. Optimized APM models demonstrated significantly improved global fit with geological and geophysical observations while performing consistently with geodynamic constraints. Critically, APM models derived by limiting average rates of NLR to ~0.05°/Myr and absolute TM velocities to ~27?mm/year fit geological observations including hotspot tracks. This suggests that this range of NLR and TM estimates may be appropriate for Earth over the last 220 Myr, providing a key step toward the practical integration of numerical geodynamics into plate tectonic reconstructions.
DS1990-0255
1990
Gurr, T.M.Bunch, J.P., Gurr, T.M.Environmental auditing as an effective management tool for the miningindustryAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Preprint, No. 90-13, 11pGlobalMining, Environmental audit
DS2000-0722
2000
GurrolaNyblade, A.A., Owens, T.J., Gurrola, Ritsema, LangstonSeismic evidence for a deep upper mantle thermal anomaly beneath east AfricGeology, Vol. 28, No. 7, July, pp. 599-602.Tanzania, Uganda, Kenya, East AfricaGeophysics - seismics, mantle, plume rift, Craton - Tanzanian
DS1989-1017
1989
Gurrola, H.Micrus, K.L., Keller, G.R., Jurick, D., Gurrola, H.Crustal structure of the southern margin of North america determined from gravity modelingGeological Society of America (GSA) Annual Meeting Abstracts, Vol. 21, No. 6, p. A99. AbstractMidcontinentGeophysics -gravity, Tectonics
DS1990-1038
1990
Gurrola, H.Mickus, K., Keller, G.R., Hamilton, L., Jurick, D., Gurrola, H.Geophysical transects across the southern midcontinent region of the UnitedStatesGeological Society of America (GSA) Annual Meeting, Abstracts, Vol. 22, No. 7, p. A191GlobalGeochronology, Geophysics
DS200512-0384
2005
Gursky, D.S.Gursky, D.S., Metalidi, V.S., Pryhodko, V.L., Geiko, Y.V.Prospects of diamond bearing ability in Ukraine and trends of geological prospecting works.Gems & Gemology, abstracts Mineralogical Journal (Ukraine) Vol. 26, 1, pp. 7-17. *** in English, Vol. 41, 2, Summer p. 194. abstract onlyEurope, UkraineStructure, occurrences
DS1982-0236
1982
Gurvich, M.Y.Gurvich, M.Y., Kozlov, A.A., Malkov, Y.V., Pavlov, Y.G., Semonov.Structures of disintegration in rutile of kimberlite in Letseng la Teraipipe, Lesotho.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 10, pp. 1520-1523LesothoBlank
DS1989-0131
1989
Gurvich, M.Yu.Bocharov, V.L., Kantersov, V.A., Gurvich, M.Yu., Chesko, V.M.Radio element distributions in the Precambrian Alkaline rocks of a dikecomplexGeochemistry International, Vol. 26, No. 9, pp. 79-84RussiaAlkaline rocks, UraniuM.
DS1995-1937
1995
Gusak, S.N.Turkin, A.I., Brey, G.P., Gusak, S.N.Stability field of ferric ferrous garnet skiagiteProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 643-645.GlobalMineralogy, Garnet -pyrope
DS1998-0064
1998
Gusak, S.N.Babich, Yu.V., Turkin, A.I., Gusak, S.N.Pecularities of high pressure coesite quartz transformation in presence of water and carbon dioxideRussian Geology and Geophysics, Vol. 39, No. 5, pp. 694-8.GlobalCoesite, Mineralogy
DS1995-0707
1995
Gusek, J.J.Gusek, J.J.Passive treatment of acid rock drainage: what is the potential bottomline?Mining Engineering, Vol. 47, No. 3, March pp. 250-253United StatesAcid rock drainage, Environmental
DS1987-0264
1987
Gusev, A.A.Gusev, A.A.Polarizability of valence bonds in crystals with the diamond structure(technical note)Soviet Physics Jetp, Vol. 21, No. 7, July pp. 810-812GlobalBlank
DS201212-0396
2012
Gusev, G.S.Lapin, A.V., Gusev, G.S.Kimberlitic and non-kimberlitic diamond potential of igneous and metamorphic rocks.Geokart GEOS, Moscow, 448p. In RUSSIANMantleDiamond genesis
DS202006-0921
2020
Gusev, N.I.Gusev, N.I., Sergeeva, L. Yu., Larionov, A.N., Skublov, S.G.Relics of the Eoarchean continental crust of the Anabar shield, Siberian Craton.Petrology, Vol. 28, 2, pp. 118-140.Russiadeposit - Daldyn

Abstract: In the northern part of the Anabar Shield, orthopyroxene plagiogneisses of the granulite Daldyn Group host lenses of mafic rocks surrounded by melanocratic rims. According to their chemical composition, the mafic rocks correspond to subalkaline gabbro, the plagiogneisses correspond to granodiorites contaminated with mafic material, and the rims are diorites. The orthopyroxene plagiogneisses of granodiorite composition have 147Sm/144Nd = 0.1097, ?Nd(?) = 1.6, TNd(DM) = 3.47 Ga and are metamorphosed anatectic granitoids with an age of 3.34 Ga. The mafic rocks have high Zr, Th, and Pb contents, are enriched in REE (?REE = 636 ppm), with a high degree of fractionation [(La/Yb)N = 17.73] and a well-defined Eu minimum (Eu/Eu* = 0.51), and have 147Sm/144Nd = 0.099, ?Nd(?) = 1.4 and TNd(DM) = 3.65 Ga. It is assumed that these rocks crystallized from melt derived from an enriched mantle (plume) source. Based on U-Pb (SHRIMP-II) dating of 50 zircon grains from the mafic rocks, a group of grains with concordant ages from 3567 to 1939 Ma was distinguished, along with a large number of discordant values. Multiple measurements in zircon grains with discordant age values make it possible to identify seven grains of Eoarchean age, with upper intercepts of the discordia corresponding to 3987 ± 71 to 3599 ± 33 Ma. The Lu-Hf systematics of 14 zircon grains is characterized by ?Hf(T) = +3.7 and by close values of THf(DM) = 3.95 and TCHf = 3.93 Ga (3.99 Ga for the oldest zircon). The Paleoarchean (3.57 Ga) zircons are characterized by negative values of ?Hf(T) = -5.3 and -6.8, THf(DM) = 3.92-3.98 Ga, and TCHf = 4.14-4.24 Ga, which indicate recycling of the preexisting Eoarchean and Hadean continental crust. The younger zircon (3287-2410 Ma) was also formed when the preexisting crust was recycled.
DS1998-1108
1998
Gusev, V.A.Palyanov, Y.N., Gusev, V.A., Kupriyanov, Borzdov, SokolThe effect of growth rate on formation of nitrogenous defects in diamond7th. Kimberlite Conference abstract, pp. 649-51.RussiaDiamond inclusions, Mineralogy
DS200812-0617
2008
Gusev, V.A.Kupriyanov, I.N., Paynamov, Yu.N., Kalinin, A.A., Sokol, A.G., Khokhryakov, A.F., Gusev, V.A.The effect of HPHT treatment on the spectroscopic features of type IIb synthetic diamonds.Diamond and Related Materials, Vol. 17, 7-10, pp. 1203-1206.TechnologyType IIb synthetics
DS1994-0955
1994
Guseva, E.M.Krot, A.N., Posukhova, Ye.V., Guseva, E.M., et al.Origin of garnets containing hydrocarbon inclusions in the Mir kimberlitepipe.Geochemistry International, Vol. 31, No. 1, pp. 122-130.Russia, YakutiaDiamond morphology, Deposit -Mir
DS1988-0236
1988
Guseva, E.V.Garanin, V.K., Guseva, E.V., Dergach, D.V.Diamond crystals in garnets from granite gneisses.(Russian)Doklady Academy of Sciences Nauk USSR, (Russian), Vol. 298, No. 1, pp. 190-194GlobalBlank
DS1993-0859
1993
Guseva, E.V.Krot, A.N., Poskukojovsky, T.V., Guseva, E.V., Galimov, E.M., Botkunov, A.I. et.Genesis of the garnets containing hydrocarbon inclusions (Mir kimberlitepipe). (Russian)Geochemistry International (Geokhimiya), (Russian), No. 6, June pp. 891-899RussiaGeochemistry -garnets, Deposit -Mir
DS1985-0340
1985
Guseva, M.B.Khvostov, V.V., Guseva, M.B., Babaev, V.G., Rylova, O. YU.Transformation of Diamond and Graphite Surfaces by Ion Irradiation.Solid State Communications, Vol. 55, No. 5, PP. 443-445.GlobalExperimental Petrology
DS200812-0681
2008
Guseva, N.S.Lobach Zhuchenko, S.B., Rollinson, H., Chekulaev, V.P., Savatenkov, V.M., Kovalenko, A.V., Martin, H., Guseva, N.S., Arestova, N.A.Petrology of Late Archean, highly potassic, sanuktoid pluton from the Baltic Shield: insights into Late Archean mantle metasomatism.Journal of Petrology, Vol. 49, 3, pp. 393-420.Europe, Baltic shieldMetasomatism
DS200812-1078
2008
Guseva, N.S.Skublov, S.G., Lobach Zhuchenko, S.B., Guseva, N.S., Gembitckaya, I.M., Tolmacheva, E.V.REE distribution in zircons from lamproites in Panozero complex of sanukitoids (Karelia, NW Russia).Goldschmidt Conference 2008, Abstract p.A875.Russia, KareliaLamproite
DS200912-0697
2009
Guseva, N.S.Skublov, S.G., Lobach-Zhuchenko, S.B., Guseva, N.S., Gembitskaya, I.M., Tolmacheva, E.V.Rare earth and trace element distribution in zircons from miaskite lamproites of the Panozero complex, central Karelia.Geochemistry International, Vol. 47, 9., Sept. pp. 901-913.RussiaLamproite
DS201112-0972
2011
Guseva, N.S.Skublov, S.G., Shchukina, E.V., Guseva, N.S., Malkovets, V.G., Golovin, N.N.Geochemical characteristics of zircons from xenoliths in the V. Grib kimberlite pipe, Archangelsk Diamondiferous province.Geochemistry International, Vol. 49, 4, pp. 415-421.Russia, Kola PeninsulaGeochemistry
DS201212-0666
2012
Guseva, N.S.Skublov, S.G., Nikitina, L.P., Marin, Yu.B., Levskii, L.K., Guseva, N.S.U Pb age and geochemistry of zircons from xenoliths of the V. Grib kimberlitic pipe, Arkhangelsk diamond province.Doklady Earth Sciences, Vol. 444, 1, pp. 595-600.Russia, Archangel, Kola PeninsulaDeposit - Grib
DS1989-0472
1989
Guseva, Ye.V.Garanin, Ye.V., Guseva, Ye.V., Dergachev, D.V., Kudryatseva, G.P.Diamond crystals in garnets from slightly gneissic graniteDoklady Academy of Science USSR, Earth Science Section, Vol. 298, No. 1-6, April pp. 92-96RussiaDiamond morphology, Gneiss, Garnet analyses
DS1995-0708
1995
Gush, E.P.Gush, E.P.Diamonds; Journal of South African Mining Institute, 1995Journal of South African Mining Institute, Vol. 94, No. 11-1, Nov-Dec. pp. 337-340.South AfricaBrief overview
DS1960-0555
1965
Gushchenko, I.I.Gushchenko, I.I.Contribution to Mechanism of Pyroclastic FragmentationInternational Geology Review, Vol. 7, No. 2, PP. 272-279.RussiaDiatreme, Genesis
DS1988-0739
1988
Gushchin, V.A.Vladimirov, Y.V., Gushchin, V.A., Denyak, V.V., Evseev, I.G., et al.Polarization of electromagnetic radiation in motion of ultra- relativistic electrons near a crystal axis ofdiamond.(Russian)Soviet Journal of Nuc. R., (Russian), Vol. 48, No. 4, Oct. pp. 768-769RussiaDiamond morphology
DS1986-0483
1986
Gushchin, V.N.Lapin, A.V., Gushchin, V.N., Lugovaya, I.P.Isotopic interaction of carbonatites and metamorphosed carbonatite sedimentary rocks.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 7, pp. 979-986RussiaCarbonatite, Geochronology
DS1987-0395
1987
Gushin, V.N.Lapin, A.V., Gushin, V.N., Lougovaya, I.P.Isotopic interact
 
 

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