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SDLRC - Scientific Articles all years by Author - Y


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 - Y
Posted/
Published
AuthorTitleSourceRegionKeywords
DS201812-2844
2018
Y, m Zhengm J-P.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.
DS202102-0227
2021
Y.Vilella, K., Bodin, T., Boukare, C-E.,Deschamp, F., Badro, J., Ballmer, M.D. Li, Y.Constraints on the composition and temperature of LLSVPs from seismic properties of lower mantle minerals.Earth and Planetary Science Letters, Vol. 554, doi:10.1016/j.epsl.2020.116685Mantlegeophysics - seismic

Abstract: Here, we provide a reappraisal of potential LLSVPs compositions based on an improved mineralogical model including, for instance, the effects of alumina. We also systematically investigate the effects of six parameters: FeO and Al2O3 content, proportion of CaSiO3 and bridgmanite (so that the proportion of ferropericlase is implicitly investigated), Fe3+/?Fe and temperature contrast between far-field mantle and LLSVPs. From the 81 millions cases studied, only 79000 cases explain the seismic observations. Nevertheless, these successful cases involve a large range of parameters with, for instance, FeO content between 12--25~wt\% and Al2O3 content between 3--17~wt\%. We then apply a principal component analysis (PCA) to these cases and find two robust results: (i) the proportion of ferropericlase should be low (<6vol\%); (ii) the formation of Fe3+-bearing bridgmanite is much more favored than other iron-bearing phases. Following these results, we identify two end-member compositions, Bm-rich and CaPv-rich, and discuss their characteristics. Finally, we discuss different scenarios for the formation of LLSVPs and propose that investigating the mineral proportion produced by each scenario is the best way to evaluate their relevance. For instance, the solidification of a primitive magma ocean may produce FeO and Al2O3 content similar to those suggested by our analysis. However, the mineral proportion of such reservoirs is not well-constrained and may contain a larger proportion of ferropericlase than what is allowed by our results.
DS1995-2093
1995
Yaalon, D.H.Yaalon, D.H.The soils we classify. Essay review of recent publications on soiltaxonomyCatena, Vol. 24, No. 4, Oct. 1, pp. 233-242GlobalSoils, geomorphology, Classification
DS2002-1445
2002
Yabovskaya, T.B.Sgrigna, V., D'Ambrosio, C., Yabovskaya, T.B.Numerical modeling of preseismic slow movements crustal blocks caused by quasi-horizontal tectonic forcesPhysics of the Earth and Planetary Interiors, Vol.129, 3-4, pp.313-24.MantleTectonics
DS200912-0828
2009
Yabubchuk, A.Yabubchuk, A.Diamond deposits of the Siberian Craton: products of post 1200 Ma plume events affecting the lithospheric keel.Ore Geology Reviews, Vol. 15, pp. 155-163.Russia, SiberiaDiamond deposits
DS2002-1462
2002
Yabuta, H.Shimoyama, A., Yabuta, H.Mono and bicyclic alkanes and diamondoid hydrocarbons in the Cretaceous Tertiary boundary sediments HokkaidoGeochemical Journal, Vol.36,pp.173-89., Vol.36,pp.173-89.JapanGeochemistry - not on topic but interesting, Diamondoid hydrocarbons
DS2002-1463
2002
Yabuta, H.Shimoyama, A., Yabuta, H.Mono and bicyclic alkanes and diamondoid hydrocarbons in the Cretaceous Tertiary boundary sediments HokkaidoGeochemical Journal, Vol.36,pp.173-89., Vol.36,pp.173-89.JapanGeochemistry - not on topic but interesting, Diamondoid hydrocarbons
DS1992-1710
1992
Yacoot, A.Yacoot, A., Moore, M.An unusual octahedral diamondMineralogical Magazine, Vol. 56, No. 382, March pp. 111-113GlobalDiamond morphology, Mineralogy
DS1993-1785
1993
Yacoot, A.Yacoot, A., Moore, M.X-ray topography of natural tetrahedral diamondsMineralogical Magazine, Vol. 57, No. 387, June pp. 223-230.South AfricaDiamond morphology, Williams' collection diamonds, X-ray
DS200812-0427
2007
Yadrenkin, A.V.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
DS1997-0926
1997
Yagel, R.Pride, D.E., Memmi, J.M., Loomis, J., Yagel, R.SEARCHMAP - interactive map interpretation system for mineral explorationExplore., No. 95, April pp. 1, 3-10MidcontinentComputer - GIS, Remote sensing, GIS datasets
DS1997-0927
1997
Yagel, R.Pride, D.E., Memmi, J.M., Loomis, J., Yagel, R.SEARCHMAP - interactive map exploration system for mineral exploration.Specific application for diamonds.Explore, No. 95, April pp. 1, 3-10.MidcontinentGIS, Map information data
DS2001-0783
2001
YagiMiyajima, N., Yagi, Hirose, Kondo, Fujino, MiuraPotential host phase of aluminum and potassium in the Earth's lower mantleAmerican Mineralogist, Vol. 86, pp. 740-46.MantleAlkali earth elements
DS200512-1063
2005
YagiSueda, Y., Irifune, T., Nishiyama, N., Rapp, Ferroir, Onozawa, Yagi, Merkel, Miyajima, FunakoshiA new high pressure form of K Al Si3 08 under lower mantle conditions.Geophysical Research Letters, Vol. 31, 23, Dec. 16, DOI 10.1029/2004 GLO21156MantleUHP
DS1960-0769
1966
Yagi, K.Yagi, K., Matsumoto, H.Note on the Leucite Bearing Rocks from the Leucite Hills, Wyoming.Journal of FACULTY SCI. HOKKAIDO University SER. 4, GEOL. MIN., Vol. 13, No. 3, PP. 301-315.GlobalLeucite Hills, Leucite, Rocky Mountains
DS1975-0191
1975
Yagi, K.Sobolev, V.S., Bazarova, T.YU., Yagi, K.Crystallization Temperatures of Wyomingite from Leucite HillContributions to Mineralogy and Petrology, Vol. 49, PP. 301-308.GlobalLeucite Hills, Leucite, Rocky Mountains
DS1980-0150
1980
Yagi, K.Gupta, A.K., Yagi, K.Leucite Bearing Rocks of Manchuria, ChinaSpringer-verlag Publishing, 252P. PP. 86-89. CHINA.ChinaBlank
DS1980-0151
1980
Yagi, 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
Yagi, 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
DS1986-0319
1986
Yagi, 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
Yagi, 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
DS1998-0779
1998
Yagi, T.Kondo, T., Yagi, T.Phase transition of pyrope garnet under lower mantle conditionsAmerican Geophysical Union (AGU) Geo. Mon., No. 101, pp.MantleGarnet - pyrope
DS1998-0932
1998
Yagi, T.Manghnani, M.H., Yagi, T.Properties of earth and planetary materials at high pressure andtemperature.American Geophysical Union (AGU) Geophys. Monograph., No. 101, 558p. $ 90.00MantleSeperate articles cited of interest
DS2002-1754
2002
Yagi, T.Yagi, T.Behaviour of Earth Materials under deep mantle conditionsProceedings - International School of Physics Enrico Fermi, Vol. 147, pp. 643-56.. Ingenta 1025439481MantleReactions
DS200412-0590
2004
Yagi, T.Fujino, K., sasaki, Y., Komori, T., Ogawa, H., Miyajima, N., Sata, N., Yagi, T.Approach to the mineralogy of the lower mantle by a combined method of a laser heated diamond anvil cell experiment and analyticPhysics of the Earth and Planetary Interiors, Vol. 143-144, pp. 215-221.MantleMineralogy - experimental
DS201412-0403
2014
Yagi, T.Imada, S., Ohta, K., Yagi, T., Hirose, K., Yoshida, H., Nagahara, H.Measurements of lattice thermal conductivity of MgO to core-mantle boundary.Geophysical Research Letters, Vol. 41, 13, pp. 4542-4547.MantleGeothermometry
DS201704-0643
2017
Yagi, T.Ohta, K., Yagi, T., Hirose, K., Ohishi, Y.Thermal conductivity of ferropericlase in the Earths's lower mantle.Earth and Planetary Science Letters, Vol. 465, pp. 29-37.MantleGeothermometry

Abstract: (Mg,?Fe)O ferropericlase (Fp) is one of the important minerals comprising Earth's lower mantle, and its thermal conductivity could be strongly influenced by the iron content and its spin state. We examined the lattice thermal conductivity of (Mg,?Fe)O Fp containing 19 mol% iron up to 111 GPa and 300 K by means of the pulsed light heating thermoreflectance technique in a diamond anvil cell. We confirmed a strong reduction in the lattice thermal conductivity of Fp due to iron substitution as reported in previous studies. Our results also show that iron spin crossover in Fp reduces its lattice thermal conductivity as well as its radiative conduction. We also measured the electrical conductivity of an identical Fp sample up to 140 GPa and 2730 K, and found that Fp remained an insulator throughout the experimental conditions, indicating the electronic thermal conduction in Fp is negligible. Because of the effects of strong iron impurity scattering and spin crossover, the total thermal conductivity of Fp at the core-mantle boundary conditions is much smaller than that of bridgmanite (Bdg). Our findings indicate that Bdg (and post-perovskite) is the best heat conductor in the Earth's lower mantle, and distribution of iron and its valence state among the lower mantle minerals are key factors to control the lower mantle thermal conductivity.
DS202009-1649
2020
Yagi, T.Okuda, Y., Ohta, K., Haseawa, A., Yagi, T., Hirose, K., Kawaguchi, S.I., Ohishi, Y.Thermal conductivity of Fe bearing post- perovskite in the Earth's lowermost mantle.Earth and Planetary Science Letters, Vol. 547, 9p. PdfMantleperovskite

Abstract: The thermal conductivity of post-perovskite (ppv), the highest-pressure polymorph of MgSiO3 in the Earth's mantle, is one of the most important transport properties for providing better constraints on the temperature profile and dynamics at the core-mantle boundary (CMB). Incorporation of Fe into ppv can affect its conductivity, which has never been experimentally investigated. Here we determined the lattice thermal conductivities of ppv containing 3 mol% and 10 mol% of Fe at high P-T conditions - of pressures up to 149 GPa and 177 GPa, respectively, and temperatures up to 1560 K - by means of the recently developed pulsed light heating thermoreflectance technique combining continuous wave heating lasers. We found that the incorporation of Fe into ppv moderately reduces its lattice thermal conductivity as it increases the Fe content. The bulk conductivity of ppv dominant pyrolite is estimated as 1.5 times higher than that of pyrolite consisting of bridgmanite and ferropericlase in the lower mantle, which agrees with the traditional view that ppv acts as a better heat conductor than bridgmanite in the Earth's lowermost mantle.
DS1997-1277
1997
Yagmurlu, F.Yagmurlu, F., Savascin, Y., Ergun, M.Relation of alkaline volcanism and active tectonism within the evolution Of the I sparta Angle, southwest TurkeyJournal of Geology, Vol. 105, No. 6, Nov. pp. 717-728Turkeyvolcanism., Tectonics
DS1989-1666
1989
Yagneyshev, B.S.Yagneyshev, B.S., Yagnysheva, T.A., Khmelevskiy, V.A.Practical significance of lithogeochemical characteristics of secondary dispersion aureoles near kimberlites.(Russian)Mineralogischeskiy Sbornik, (L'vov), (Russian), Vol. 43, No. 2, pp. 77-82.Russia, YakutiaGeochemistry, Siberian Platform
DS1984-0781
1984
Yagnyshev, B.S.Yagnyshev, B.S., Yagnysheva, T.A., Khmelevskiy, V.A., Zatkhey, R.A.Mineral composition pecularities of the lower Paleozoic rocks around kimberlite bodies, west Yakutia.(Russian)Mineral. Zhurn., (Russian), Vol. 38, No. 1, pp. 49-55RussiaBlank
DS1987-0819
1987
Yagnyshev, B.S.Yagnyshev, B.S., Khmelevekiy, V.A.The concealed halo dispersion patterns of Yakutia kimberlites.(Russian)Mineral. Sbornik (L'Vov), (Russian), Vol. 41, No. 1, pp. 87-91RussiaGeochemistry, Deposit -Yakutia area
DS1984-0781
1984
Yagnysheva, T.A.Yagnyshev, B.S., Yagnysheva, T.A., Khmelevskiy, V.A., Zatkhey, R.A.Mineral composition pecularities of the lower Paleozoic rocks around kimberlite bodies, west Yakutia.(Russian)Mineral. Zhurn., (Russian), Vol. 38, No. 1, pp. 49-55RussiaBlank
DS1989-1666
1989
Yagnysheva, T.A.Yagneyshev, B.S., Yagnysheva, T.A., Khmelevskiy, V.A.Practical significance of lithogeochemical characteristics of secondary dispersion aureoles near kimberlites.(Russian)Mineralogischeskiy Sbornik, (L'vov), (Russian), Vol. 43, No. 2, pp. 77-82.Russia, YakutiaGeochemistry, Siberian Platform
DS202107-1127
2021
Yagoutz, E.Shatsky, V.S., Ragozin, A.L., Skuzovatov, S. Yu., Kozmenko, O.A., Yagoutz, E.Isotope-geochemical evidence of the nature of protoliths of diamondiferous rocks of the Kokchetav subduction-collision zone ( northern Kazakhstan).Russian Geology and Geophysics, Vol. 62, pp. 547-556, pdfRussia, Kazakhstandeposit - Kokchetav

Abstract: The isotope-geochemical features of diamondiferous metamorphic rocks of the Kokchetav subduction–collision zone (KSCZ) show that both the basement rocks and the sediments of the Kokchetav massif were their protoliths. A whole-rock Sm–Nd isochron from the diamondiferous calc-silicate, garnet–pyroxene rocks and migmatized granite-gneisses of the western block of the KSCZ yielded an age of 1116 ± 14 Ma, while an age of 1.2–1.1 Ga was obtained by U–Pb dating of zircons from the granite-gneiss basement of the Kokchetav microcontinent. Based on these data, we assume that the protoliths of the calc-silicate, garnet–pyroxene rocks and the granite-gneisses of the KSCZ were the basement rocks sharing an initially single Nd source, which was not influenced by high- to ultrahigh-pressure metamorphism (~530 Ma). Therefore, their geochemical features are probably not directly related to ultrahigh-pressure metamorphism. The corresponding rock associations lack isotope-geochemical evidence of partial melting that would occur during ultrahigh-pressure metamorphism, which suggesting that they were metamorphosed under granulite-facies conditions. At the same time, the high-alumina diamondiferous rocks of the Barchi area (garnet–kyanite–mica schists and granofelses), which were depleted to different degrees in light rare-earth elements (REE) and K, have yielded a Sm–Nd whole-rock isochron age of 507 ± 10 Ma indicating partial melting of these rocks during their exhumation stage. The close ?Nd (1100) values of the basement rocks and garnet–kyanite–mica schist with geochemical characteristics arguing against its depletion during high-pressure metamorphism indicate that the basement rocks were a crustal source for high-alumina sediments.
DS200512-0987
2004
YagovkinaSimakov, 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
DS202105-0785
2021
Yahalom, A.Rabinowitz, Y., Etinger, A., Litvak, B., Yahalom, A., Cohen, H., Pinhasi, Y.Millimeter wave spectroscopy for evaluating diamond color grades.Diamond & Related Materials, Vol. 116, 108386 10p. PdfGlobalspectroscopy

Abstract: One of the most important parameters affecting the value of natural colorless diamonds is its light transparency, defined as its color grade. The regular range of color grades in the trade is denoted by alphabet letters in the range D-M, where D represents the best commercial quality. The color grade of diamonds is largely influenced by their nitrogen content (when nitrogen atoms substitute carbon atoms in the crystal) and can be determined from this property. Diamonds absorb electromagnetic radiation in the UV-visible as well as in the Infrared spectral range and therefore, their color grade is measured via spectroscopic light absorption in these frequency range. The electromagnetic properties of different polished diamonds having several nitrogen concentrations in the frequency range of 100-110 GHz (W band) have been studied. The results indicate that there is a good correlation between the amount of nitrogen impurities and the Free Spectral Range (FSR) parameter of a reflection signal, S11, in the antenna. From the study It is concluded that measuring the diamonds dielectric properties via spectroscopic analysis in the millimeter wavelength range, can determine the color grading. In addition, the FSR measurements were correlated well with the FTIR measurements. The methodology of the new color determination mode and a novel color estimate, based on the FSR vs the nitrogen correlation, has been tested on 26 diamonds with a success rate higher than 70%.
DS201312-0956
2013
Yahata, N.Wang, Y., Hilairet, N., Nishiyama, N., Yahata, N., Tsuchiya, T., Morad, G., Fiquet, G.High pressure, high temperature deformation of CaGeO3 ( perovskite) +-MgO aggregates: implications for multiphase rheology of the lower mantle.Geochemistry, Geophysics, Geosystems: G3, Vol. 14, 9, pp. 3389-3408.MantlePerovskite
DS200912-0829
2009
Yahoo FinanceYahoo FinanceMemorial diamonds deliver eternal life. Algordanza ( from ashes or hair).Finance.yahoo.com, June 23, 1/2p.TechnologyNews item - Algordanza
DS1995-1179
1995
Yajima, H.Matsuda, J.I., Kasumi, A., Yajima, H.Noble gas studies in diamond synthesized shock loading in laboratory And implications on origin in ureilites.Geochim. Cosmochimica Acta, Vol. 59, No. 23, Dec. 1, pp. 4939-4950.GlobalUreilites
DS201312-0988
2013
Yajima, T.Yajima, T., Yamaguchi, Y.Geological mapping of the Francistown area in northeastern Botswana by surface temperature and spectral emissivity information derived from advanced spaceborn thermal emission and reflection radiometer (ASTER) thermal infrared data.Ore Geology Reviews, Vol. 53, pp. 134-144.Africa, BotswanaGeothermometry - Aster
DS1993-1786
1993
Yakarov, K.T.Yakarov, K.T.Placer mining by Almazy Rossii Sakha CompanyDiamonds of Yakutia, pp. 161-162.Russia, YakutiaMining, Alluvials
DS202102-0237
2021
Yakmchuck, C.Yakmchuck, C., Kirkland, C.L., Cavosie, A.J., Szilas, K., Hollis, J., Gardinerm N.J., Waterton, P., Steenfelt, A., Martin, L.Stirred not shaken; critical evaluation of a proposed Archean meteorite impact in West Greenland.Earth and Planetary Science Letters, Vol. 557, doi.org/10.1016/ j.epsl.2020.116730 9p. PdfEurope, Greenlandmeteorite

Abstract: Large meteorite impacts have a profound effect on the Earth's geosphere, atmosphere, hydrosphere and biosphere. It is widely accepted that the early Earth was subject to intense bombardment from 4.5 to 3.8 Ga, yet evidence for subsequent bolide impacts during the Archean Eon (4.0 to 2.5 Ga) is sparse. However, understanding the timing and magnitude of these early events is important, as they may have triggered significant change points to global geochemical cycles. The Maniitsoq region of southern West Greenland has been proposed to record a ?3.0 Ga meteorite impact, which, if confirmed, would be the oldest and only known impact structure to have survived from the Archean. Such an ancient structure would provide the first insight into the style, setting, and possible environmental effects of impact bombardment continuing into the late Archean. Here, using field mapping, geochronology, isotope geochemistry, and electron backscatter diffraction mapping of 5,587 zircon grains from the Maniitsoq region (rock and fluvial sediment samples), we test the hypothesis that the Maniitsoq structure represents Earth's earliest known impact structure. Our comprehensive survey shows that previously proposed impact-related geological features, ranging from microscopic structures at the mineral scale to macroscopic structures at the terrane scale, as well as the age and geochemistry of the rocks in the Maniitsoq region, can be explained through endogenic (non-impact) processes. Despite the higher impact flux, intact craters from the Archean Eon remain elusive on Earth.
DS201212-0798
2012
Yakob, J.L.Yakob, J.L., Feineman, M.D., Deane, J.A., Eggler, D.H., Penniston-Dorland, S.C.Lithium partitioning between olivine and diopside at upper mantle conditions: as experimental study.Earth and Planetary Science Letters, Vol. 329-330, pp. 11-21.MantleTechnology
DS1985-0600
1985
Yakol.Serebrya, N.R., Losev, V.G., Voronov, O.A., Rakmani, A.V., Yakol.The Morphology of Diamond Crystals Synthesized from Hydrocarbons. a Technical Note.Kristallogr., Vol. 30, No. 5, PP. 1026-1027.RussiaDiamond Morphology, Synthetics
DS201811-2585
2018
Yakolev, D.Kostrovitsky, S., Yakolev, D.Deciphering kimberlite field structure using ilmenite composition: example of Daldyn field ( Yakutia).European Journal of Mineralogy, doi.org./ 101127/ejm/2018/0030-2783 cost $ 30.00 USRussiadeposit - Daldyn

Abstract: The spatial distribution patterns of Mg-bearing ilmenite (Ilm) composition were studied on 54 kimberlite bodies of the Daldyn field in the Yakutian kimberlite province. The representativity of the ilmenites sampled in this study is ensured by analysing ca. 100 grains from each kimberlite body. The major conclusions are as follows: (1) ilmenites from neighbouring pipes within the same linear cluster have similar average compositions and compositional fields on the MgO-Cr2O3 plots; (2) ilmenites from different clusters of pipes show different average compositions and compositional fields on the MgO-Cr2O3 plots. (3) regardless of belonging to different clusters, low-Mg Ilm across the whole Daldyn field is characterized by a direct correlation between Al2O3 and MgO; (4) significant changes of MgO content are observed in high-Mg Ilm, while Al2O3 content remains at the same level. The similarity of Ilm compositions across the kimberlite field, as shown by the MgO-Al2O3 plots, is due to a common asthenospheric source. The similar Ilm compositions in different bodies within cluster of pipes is accounted for by a single supply of magma via a lithospheric mantle channel for all pipes of the cluster. The composition of the kimberlite melts can be altered owing to the incorporation and assimilation of lithospheric mantle rocks rich in Mg and Cr. These changes of the melt cause corresponding changes in the Ilm macrocryst composition, both during and after crystallization of Ilm. Thus, the Ilm macrocryst composition follows a trend from low-Mg/low-Cr for Ilm crystallizing in the asthenosphere, to high-Mg/high-Cr at higher levels in the lithosphere. The key conclusion of this study is that Ilm can be used to decipher the structure of kimberlite fields. This can provide a reliable geological criterion for grouping an association of pipes together in clusters, which were previously identified only through subjective considerations of the spatial proximity of kimberlite bodies.
DS201212-0376
2012
Yakolev, D.A.Kostrovitskii, S.I., Soloveva, L.V., Gornova, M.A., Alymova, N.V., Yakolev, D.A., Ignative, A.V., Velivetskaya, T.A., Suvorova, L.F.Oxygen isotope composition in minerals of mantle parageneses from Yakutian kimberlites.Doklady Earth Sciences, Vol. 444, 1, pp. 579-584.Russia, YakutiaDeposit - Udachnaya, Komsomolskaya
DS201212-0377
2012
Yakolev, D.A.Kostrovitsky, S.I., Kopylova, M.G., Egorov, K.N., Yakolev, D.A., Kalashnikova, T.V., Sandmirova, G.P.The exceptionally fresh Udachnaya -East kimberlite: evidence for brine and evaporite contamination.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractRussia, YakutiaDeposit - Udachnaya -east
DS201212-0378
2012
Yakolev, D.A.Kostrovitsky, S.I.,Gornova, M.A.,Solovyevas, L.V., Yakolev, D.A.Isotope heterogeneity from oxygen in rocks of lithospheric mantle.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussiaDeposit - Udachnaya
DS201212-0799
2012
Yakolev, D.A.Yakolev, D.A., Kostrovitsky, S., Suvorova, L.F.Typomorphic features of groundmass minerals from Diamondiferous kimberlites of Yakutia.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, YakutiaPetrology
DS201603-0392
2016
Yakolev, D.A.Kostrovitsky, S.I., Skuzovatov, S.Y., Yakolev, D.A., Sun, J., Nasdala, L., Wu, F.Age of Siberian craton crust beneath the northern kimberlite fields: insights to the craton evolution. ( Olenek -Anabar)Gondwana Research, in press available 70p.RussiaGeochronology

Abstract: Comprehensive studies of zircon xenocrysts from kimberlites of the Kuoika field (northeastern Siberian craton) and several kimberlite fields of the eastern Anabar shield, along with data compilation on the age of kimberlite-hosting terranes, reveal details of the evolution of the northern Siberian craton. The age distribution and trace element characteristic of zircons from the Kuoika field kimberlites (Birekte terrane) provide evidence of significant basic and alkaline-carbonatite magmatism in northern Siberia in the Paleozoic and Mesozoic periods. The abundance of 1.8-2.1 Ga zircons in both the Birekte and adjacent Hapchan terranes (the latter hosting kimberlites of the eastern Anabar shield) supports the Paleoproterozoic assembly and stabilization of these units in the Siberian craton and the supercontinent Columbia. The abundance of Archean zircons in the Hapchan terrane reflects the input of an ancient source other than the Birekte terrane and addresses the evolution of the terrane to west (Magan and Daldyn terranes of the Anabar shield). The present study has also revealed the oldest known remnant of the Anabar shield crust, whose 3.62 Ga age is similar to that of the other ancient domain of Siberia, the Aldan shield. The first Hf isotope data for the Anabar shield coupled with the U-Pb systematics indicate three stages of crustal growth (Paleoproterozoic, Neoarchean and Paleoarchean) and two stages of the intensive crustal recycling in the Paleoproterozoic and Neoarchean. Intensive reworking of the existing crust at 2.5-2.8 Ga and 1.8-2.1 Ga is interpreted to provide evidence for the assembly of Columbia. The oldest Hf model age estimation provides a link to Early Eoarchean (3.7-3.95 Ga) and possibly to Hadean crust. Hence, some of the Archean cratonic segments of the Siberian craton could be remnants of the Earth's earliest continental crust.
DS202002-0196
2020
Yakolev, D.A.Kostrovitsky, S.I., Yakolev, D.A.The origin of salts in unaltered kimberlites. Comment on Abersteiner article Journal of Petrology, in press available, 13p.Russiadeposit - Udachnaya-East

Abstract: The article by Abersteiner et al., (2018) discussing the mantle origin of salts in serpentine-free kimberlites from the Udachnaya-East pipe contradicts the views of Kostrovitsky et al. (2013) concerning the origin of these salts from a surface source of brines. Here we wish to emphasize that Abersteiner et al. (2018) have presented erroneous statements regarding the genesis of these rocks. On the basis of the data collected by hydrogeologists working at Udachnaya-East we consider that unaltered kimberlites occur at 400-500 m depth, where the brines precipitated salts. The relation of unaltered kimberlites to the surface sources of salt is illustrated by the cross sections of the Mir and International’naya pipes, where serpentine-free kimberlites occur at the depths of Cambrian evaporite host rocks intercalated with thick halite layers. It is assumed that the salts from surface sources prevented olivine serpentinization. The secondary origin of salts in serpentine-free kimberlites is confirmed by our investigations and the hypothesis regarding the mantle origin of salts is doubtful.
DS202005-0743
2020
Yakolev, D.A.Kostrovitsky, S.I., Yakolev, D.A., Soltys, A., Ivanov, A.S., Matsyuk, S.S., Robles-Cruz, S.E.A genetic relationship between magnesian ilmenite and kimberlites of the Yakutian diamond fields.Ore Geology Reviews, Vol. 120, 16p. PdfRussia, Yakutiailmenite

Abstract: We present new major element geochemical data, and review the existing data for ilmenite macrocrysts, megacrysts, as well as ilmenite in mantle xenoliths from four diamondiferous kimberlite fields in the Yakutian province. This combined data set includes 10,874 analyses of ilmenite from 94 kimberlite pipes. In the studied samples we identify various different ilmenite compositional distributions (e.g., “Haggerty's parabola”, or “Step-like” trends in MgO-Cr2O3 bivariate space), which are common to all kimberlites from a given cluster, but the compositional distributions differ between clusters. We propose three stages of ilmenite crystallization: 1) Mg-Cr poor ilmenite crystallising from a primitive asthenospheric melt (the base of Haggerty's parabola on MgO-Cr2O3 plots). 2) This primitive asthenospheric melt was then modified by the partial assimilation of lithospheric material, which enriched the melt in MgO and Cr2O3 (left branch of Haggerty’s parabola). 3) Ilmenite subsequently underwent sub-solidus recrystallization in the presence of an evolved kimberlite melt under increasing oxygen fugacity (ƒO2) conditions (right branch of Haggerty’s parabola in MgO-Cr2O3 plots). Significant differences in the ilmenite compositional distribution between different kimberlite fields are the result of diverse conditions during subsequent ilmenite crystallization in a kimberlite melt ascending through the lithospheric mantle, which have different textures and compositions beneath the studied kimberlite fields. We propose that a TiO2 fluid formed due to immiscibility of an asthenospheric melt with low Cr and high Ti contents. This fluid infiltrated lithospheric mantle rocks forming Mg-ilmenite. These features indicate a genetic link between ilmenite and the host kimberlite melt.
DS202107-1107
2021
Yakolev, D.A.Kostrovitsky, S.I., Yakolev, D.A., Suvorova, L.F., Demonterova, E.I.Carbonatite-like rock in a dike of the Aikhal kimberlite pipe: comparison with carbonatites of the Nomokhtookh site ( Anabar area).Russian Geology and Geophysics, Vol. 62, pp. 605-618.Russiadeposit - Aikhal

Abstract: A dike of rock similar in composition to carbonatites has been found in the Aikhal diamondiferous pipe of the Alakit-Markha field of the Yakutian kimberlite province (YaKP). The fine-grained rock of essentially carbonate composition (dolomite and calcite) rich in thin-platy phlogopite contains minerals typical of carbonatites: monazite, baddeleyite, and pyrochlore. In the high contents and distribution of incompatible elements the rock differs significantly from kimberlites and is transitional from kimberlites to carbonatites. The content of incompatible elements in this rock is 3-5 times lower than that in carbonatite breccias of the pipes in the Staraya Rechka kimberlite field of the YaKP (Nomokhtookh site). The compositions of accessory trace element minerals from the Aikhal dike rock and the Nomokhtookh carbonatite breccias are compared. An assumption is made that the high contents of incompatible elements in the carbonatite-like rock, which caused the crystallization of accessory minerals, are due to the differentiation of kimberlite melt/fluid. The high Sr isotope ratios indicate that the rock altered during hydrothermal and metasomatic processes. The obtained data on the composition of the carbonatite-like rock cannot serve as an argument for the genetic relationship between the Aikhal kimberlites and typical carbonatites. The genetic relationship between kimberlites and carbonatites in the northern fields of the YaKP remains an open issue.
DS202202-0201
2022
Yakolev, D.A.Kostrivitsky, S.I., Yakolev, D.A., Sharygin, I.S., Gladkochub, D.P., Donskaya, T.V., Tretiakova, I.G., Dymshits, A.M.Diamondiferous lamproites of Ingashi field, Siberian craton.Geological Society of London Special Publication 513, pp. 45-70.Russialamproites

Abstract: Ingashi lamproite dykes are the only known primary sources of diamond in the Irkutsk district (Russia) and the only non-kimberlitic one in the Siberian craton. The Ingashi lamproite field is situated in the Urik-Iya graben within the Prisayan uplift of the Siberian craton. The phlogopite-olivine lamproites contain olivine, talc, phlogopite, serpentine, chlorite, olivine, garnet, chromite, orthopyroxene, clinopyroxene as well as Sr-F-apatite, monazite, zircon, armolcolite, priderite, potassium Mg-arfvedsonite, Mn-ilmenite, Nb-rutile and diamond. The only ultramafic lamprophyre dyke is composed mainly of serpentinized olivine and phlogopite in the talc-carbonate groundmass and is similar to Ingashi lamproites accessory assemblage with the same major element compositions. Trace element and Sr-Nd isotopic relationships of the Ingashi lamproites are similar to classic lamproites. Different dating methods have provided the ages of lamproites: 1481 Ma (Ar-Ar phlogopite), 1268 Ma (Rb-Sr whole rock) and 300 Ma (U-Pb zircon). Ingashi lamproite ages are controversial and require additional study. The calculated pressure of 3.5 GPamax for clinopyroxenes indicates that lamproite magma originated deeper than 100 km. A Cr-in-garnet barometer shows a 3.7-4.3 GPamin and derivation of Ingashi lamproites deeper than 120 km in depth. Based on the range of typical cratonic geotherms and the presence of diamonds, the Ingashi lamproite magma originated at a depth greater than 155 km.
DS200812-0597
2008
Yakolev, D.A.A.Kostrovitsky, S.A.I.A., Alymova, N.A., Yakolev, D.A.A., Solvaceva, L.A.V.A., Gornova, M.A.A.A.Origin of garnet megacrysts from kimberlites.Doklady Earth Sciences, Vol. 420, 1, pp. 636-640.RussiaPetrology
DS1984-0782
1984
Yakolev, E.N.Yakolev, E.N., Voronov, O.A., Rakhmania, A.V.Synthesis of Diamonds from HydrocarbonsSoviet Journal of Superhard Materials, Vol. 6, No. 4, pp. 9-12RussiaDiamond Morphology
DS201910-2256
2019
Yakolev, I.Dymshits, A., Sharygin, I., Yakolev, I., Malovets, V.Thermal state and composition of the lithospheric mantle beneath the Upper Muna kimberlite field, Yakutia.Goldschmidt2019, 1p. AbstractRussia, Yakutiadeposit - Upper Muna

Abstract: Mantle xenoliths brought up by kimberlitic magmas are the main source of data on the composition and physical conditions of cratonic mantle. Temperature varioations in a complete lithospheric mantle section (80-200 km) of the Siberian craton beneath the Upper Muna kimberlite filed are estimated based 49 peridotite xenolith and 330 Cpx grains from the Komsomolskaya-Magnitnaya pipe. Pressure and temperature estimates closely follow the 34.5 mW/m2 conductive geotherm. Thermal lithospere thickness is of ~ 220 km, and “diamond window” in the Paleozoic is ~75 km thick (Fig.1). Olivine compositions range in Mg# from 82 to 94 and the majority of olivenes has very high Mg# > 93. Garnets compositions mainlly follow to harzburgite-dunite and lherzolite trends plotted as Cr2O3 vs CaO. The composition of the minerals indicated the extremly depleted lithospheric mantle beneath the Upper-Muna kimberlite field. Figure 1: Model palaeogeotherms calculated using the program FITPLOT. Komsomolskaya-Magnitnaya - our data, Novinka and Udachaya are from Z16 [1]
DS1995-2094
1995
Yakolev, L.Ye.Yakolev, L.Ye., Borevskiy, L.V.Interaction between hydrodynamic, chemical and thermal processes in theearth's crustGeochemistry International, Vol. 32, No. 4, pp. 96-107GlobalGeochemistry
DS201906-1283
2018
Yakolev, V.N.Chanturia, V.A., Dvoichenkova, G.P., Morozov, V.V., Kovalchuk, O.E., Podkamenny, Y.A., Yakolev, V.N.Experimental justification of luminophore composition for indication of diamonds in x-ray luminescence separation of kimberlite ore.Journal of Mineral Science, Vol. 54, 3, pp. 458-465.Russialuminescence

Abstract: Organic and inorganic luminophores of similar luminescence parameters as diamonds are selected. Indicators, based on the selected luminophores, are synthesized. Spectral and kinetic characteristics of luminophores are experimentally determined for making a decision on optimal compositions to ensure maximum extraction of diamonds in X-ray luminescence separation owing to extra recovery of non-luminescent diamond crystals. As the components of luminophore-bearing indicators, anthracene and K-35 luminophores are selected as their parameters conform luminescence parameters of diamonds detected using X-ray luminescence separator with standard settings.
DS202111-1761
2020
Yakolev, V.N.Chanturia, V.A., Dvoichenkova, G.P., Morozov, V.V., Kovalchuk, O.E., Podkamennyi, Yu.A., Yakolev, V.N.Selective attachment of luminophore-bearing emulsion at diamonds - mechanism analysis and mode selection.Journal of Mining Science, Vol. 56, 1, pp. 96-103, 8p. PdfRussialuminescence

Abstract: The authors present an efficient modification method of X-ray fluorescence separation with mineral and organic luminophores used to adjust spectral and kinetic characteristics of anomalously luminescent diamonds. The mechanism of attachment of luminophores at diamonds and hydrophobic minerals is proved, including interaction between the organic component of emulsions and the hydrophobic surface of a treated object and the concentration of insoluble luminophore grains at the organic and water interface. Selective attachment of the luminophore-bearing organic phase of emulsion at the diamond surface is achieved owing to phosphatic dispersing agents. Tri-sodium phosphate and sodium hexametaphosphate added to emulsion reduce attachment of the luminophore-bearing organic phase at the surface of kimberlite minerals. It is shown that phosphate concentration of 1.0-1.5 g/l modifies and stabilizes spectral and kinematic parameters of kimberlite mineral on the level of initial values. This mode maintains the spectral and kinematic characteristics of anomalously luminescent diamonds at the wanted level to ensure extraction of diamonds to concentrate.
DS1988-0502
1988
Yakolev, Ya.V.Nekrasov, I.Ya., Yakolev, Ya.V., Pavlova, L.A., Gotovtsev, V.V.Unusual inclusions in native gold from the Mir kimberlite pipeDokl. Acad. Sciences USSR Earth Science Section, Vol. 303, No. 6, pp. 160-164RussiaDiamond inclusions, Gold
DS1991-1901
1991
Yakolev, Yu.N.Yakolev, Yu.N., Distler, V.V., Mitrofanov, F.P., et al.Mineralogy of platinum group elements (PGE) in the mafic-ultramafic massifs of the Kola regionMin. Petrol, Vol. 43, No. 3, February pp. 181-192RussiaPlatinuM., Mafic-ultramafic
DS200912-0830
2009
Yakoleva, O.S.Yakoleva, O.S., et al.Mineralogical and geochemical features of high alumin a fenites of the Mont Saint Hilaire alkaline complex, Quebec, Canada.alkaline09.narod.ru ENGLISH, May 10, 2p. abstractCanada, QuebecCarbonatite
DS200812-0151
2008
Yakoleva, S.Z.Buchko, I.V., Sorokin, A.P., Yakoleva, S.Z., Plotkina, Y.V.Petrology of the Early Mesozoic ultramafic mafic Luchin a massif ( southeastern periphery of the Siberian Craton).Russian Geology and Geophysics, Vol. 49, 8, pp. 570-581.RussiaUltramafic rocks
DS201112-0902
2011
Yakoleva, S.Z.Salknikova, E.B., Yakoleva, S.Z., Kotov, A.B., Plotkina, Yu.V.TIMS U-Pb dating of bastnasite, calzitite and tantalite as a powerful tool for timing of rare metal granites and carbonatites, (Eastern Siberia).Goldschmidt Conference 2011, abstract p.1785.RussiaGeochronology
DS200612-0908
2006
YakovenchukMenishikov, Y.P., Krivovichev, S.V., Pakhomovsky, Yakovenchuk, Ivanyuk, Mikhailova, Armbruster,SelivanovaChivruaiite, Ca(Ti,Nb)5(Si6O17)2 (OH,O)5.13-14H20, a new mineral from hydrothermal veins of Khibiny and Lovozero alkaline massifs.American Mineralogist, Vol. 91, 5-6, May pp. 922-928.Russia, Kola PeninsulaMineralogy - alkaline
DS1997-0175
1997
Yakovenchuk, V.Chakhmouradian, A., Yakovenchuk, V., Mitchell, R.H.Isolueshite: a new mineral of the perovskite group from Khibin a alkalinecomplex.European Journal of Mineralogy, Vol. 9, pp. 483-490.Russia, Kola PeninsulaMineralogy, Ijolite, urtite
DS1994-0120
1994
Yakovenchuk, V.N.Bayanova, T.B., Yakovenchuk, V.N.uranium-lead (U-Pb) dating of baddeleyite and zircon from imandrites on the Kolapeninsula.Doklady Academy of Sciences Acad. Science USSR, Vol. 323, No. 2, June pp. 147-150.Russia, Kola PeninsulaGeochronology
DS2003-0751
2003
Yakovenchuk, V.N.Krivovichev, S.V., Armbruster, T., Yakovenchuk, V.N., Pakhomovsky, Y.A.Crystal structure of Lamprophyllite - 2M and Lamprophyllite -2O from the LovozeroEuropean Journal of Mineralogy, Vol. 15, 4, pp. 711-18.Russia, Kola PeninsulaAlkaline rocks - mineralogy
DS200412-1056
2003
Yakovenchuk, V.N.Krivovichev, S.V., Armbruster, T., Yakovenchuk, V.N., Pakhomovsky, Y.A.Crystal structure of Lamprophyllite - 2M and Lamprophyllite -2O from the Lovozero alkaline massif, Kola Peninsula, Russia.European Journal of Mineralogy, Vol. 15, 4, pp. 711-18.Russia, Kola PeninsulaAlkaline rocks, mineralogy
DS200712-1195
2007
Yakovenchuk, V.N.Yakovenchuk, V.N., Pakhomovsky,Y.A., Menshikov, Y.P., Mikhailova, J.A., Ivanyuk, G.Y., Zalkind, O.A.Krivovichevite a new mineral species from the Lovozero alkaline massif, Kola Peninsula, Russia.The Canadian Mineralogist, Vol. 45, 3, pp. 451-456.Russia, Kola PeninsulaAlkaline rocks, mineralogy
DS200712-1196
2007
Yakovenchuk, V.N.Yakovenchuk, V.N., Pakhomovsky,Y.A., Menshikov, Y.P., Mikhailova, J.A., Ivanyuk, G.Y., Zalkind, O.A.Krivovichevite a new mineral species from the Lovozero alkaline massif, Kola Peninsula, Russia.The Canadian Mineralogist, Vol. 45, 3, pp. 451-456.Russia, Kola PeninsulaAlkaline rocks, mineralogy
DS201012-0414
2010
Yakovenchuk, V.N.Krivovichev, S.V., Yakovenchuk, V.N., Zhitova, E.S., Zolotarev, A.A., Pakhomovsky, Y.A., Ivanyuk, G.Yu.Crystal chemistry of natural layered double hydroxides, 1. Quintinite -2H-3c from the Kovdor alkaline massif, Kola Peninsula, Russia.Mineralogical Magazine, Vol. 74, pp. 821-832.Russia, Kola PeninsulaCarbonatite
DS201112-0539
2011
Yakovenchuk, V.N.Korchak, Yu.A., Menshikov, Yu.P., Pakhomovskii, Ya.A., Yakovenchuk, V.N., Ivanyuk, G.Yu.Trap formation of the Kola Peninsula.Petrology, Vol. 19, 1, pp. 87-101.Russia, Kola PeninsulaAlkaline rocks, Lovozero and Khibiny
DS201112-1175
2011
Yakovenchuk, V.N.Zolotarev, A.A., Krivovichev, S.V., Yakovenchuk, V.N., Zhitova, E.S., Pakhomovsky, Y.A., Ivanyuk, G.Y.Crystal chemistry of natural layered double hydroxides from the Kovdor alkaline massif, Kola. Polytypes of quininite: cation ordering and superstructures.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterRussia, Kola PeninsulaAlkalic
DS201507-0325
2015
Yakovenchuk, V.N.Mikhailova, J.A., Kalashnikov, A.O., Sokharev, V.A., Pakhomovsky, Y.A., Konopleva, N.G., Yakovenchuk, V.N., Bazai, A.V., Goryainov, P.M., Ivanyuk, G.Yu.3D mineralogical mapping of the Kovdor phoscorite-carbonatite complex, Russia.Mineralium Deposita, In press available. 19p.RussiaCarbonatite
DS201511-1849
2016
Yakovenchuk, V.N.Kalashnikov, A.O., Yakovenchuk, V.N., Pakhomovsky, Y.A.A., Bazai, A.V., Sokharev, V.A., Konopleva, N.G., Mikhailova, J.A., Goryainov, P.M., Ivanyuk, G.Yu.Scandium of the Kovdor baddeleyite apatite magnetite deposit ( Murmansk region, Russia): mineralogy, spatial distribution, and potential source.Ore Geology Reviews, Vol. 72, pp. 532-537.RussiaCarbonatite
DS201602-0216
2015
Yakovenchuk, V.N.Konopleva, N.G., Ivanyuk, G.Yu., Pakhomovsky, Ya.A., Yakovenchuk, V.N., Mikhailova, Yu.A., Selivanova, E.A.Typochemistry of rinkite and products of its alteration in the Khibiny alkaline pluton, Kola Peninsula.Geology of Ore Deposits, Vol. 57, 7, pp. 614-625.Russia, Kola PeninsulaDeposit - Khibiny

Abstract: The occurrence, morphology, and composition of rinkite are considered against the background of zoning in the Khibiny pluton. Accessory rinkite is mostly characteristic of foyaite in the outer part of pluton, occurs somewhat less frequently in foyaite and rischorrite in the central part of pluton, even more sparsely in foidolites and apatite-nepheline rocks, and sporadically in fenitized xenoliths of the Lovozero Formation. The largest, up to economic, accumulations of rinkite are related to the pegmatite and hydrothermal veins, which occur in nepheline syenite on both sides of the Main foidolite ring. The composition of rinkite varies throughout the pluton. The Ca, Na, and F contents in accessory rinkite and amorphous products of its alteration progressively increase from foyaite and fenitized basalt of the Lovozero Formation to foidolite, rischorrite, apatite-nepheline rocks, and pegmatite-hydrothermal veins.
DS201602-0225
2015
Yakovenchuk, V.N.Menshikov, Yu.P., Mikhailova, Yu.A., Pakhomovsky, Ya.A., Yakovenchuk, V.N., Ivanyuk, G.Yu.Minerals of zirconolite group from fenitized xenoliths in nepheline syenites of Khibiny and Lovozero plutons, Kola Peninsula.Geology of Ore Deposits, Vol. 57, 7, pp. 591-599.Russia, Kola PeninsulaDeposit - Lovozero

Abstract: Zirconolite, its Ce-, Nd-, and Y-analogs, and laachite, another member of the zirconolite group, are typomorphic minerals of the fenitized xenoliths in nepheline syenite and foidolite of the Khibiny-Lovozero Complex, Kola Peninsula, Russia. All these minerals are formed at the late stage of fenitization as products of ilmentie alteration under the effect of Zr-bearing fluids. The diversity of these minerals is caused by the chemical substitutions of Na and Ca for REE, Th, and U compensated by substitution of Ti and Zr for Nb, Fe and Ta, as well as by the redistribution of REE between varieties enriched in Ti (HREE) or Nb (LREE). The results obtained can be used in the synthesis of Synroc-type titanate ceramics assigned for the immobilization of actinides.
DS201602-0226
2016
Yakovenchuk, V.N.Mikhailova, J.A., Kalashnikov, A.O., Sokharev, V.A., Pakhomovsky, Y.A., Konopleva, N.G., Yakovenchuk, V.N., Bazai, A.V., Goryainov, P.M., Ivanyuk, G.Y.3D mineralogical mapping of the Kovdor phoscorite carbonatite complex ( Russia).Mineralium Deposita, Vol. 51, 1, pp. 131-149.RussiaDeposit - Kovdor

Abstract: The Kovdor baddeleyite-apatite-magnetite deposit in the Kovdor phoscorite-carbonatite pipe is situated in the western part of the zoned alkali-ultrabasic Kovdor intrusion (NW part of the Fennoscandinavian shield; Murmansk Region, Russia). We describe major intrusive and metasomatic rocks of the pipe and its surroundings using a new classification of phoscorite-carbonatite series rocks, consistent with the IUGS recommendation. The gradual zonation of the pipe corresponds to the sequence of mineral crystallization (forsterite-hydroxylapatite-magnetite-calcite). Crystal morphology, grain size, characteristic inclusions, and composition of the rock-forming and accessory minerals display the same spatial zonation pattern, as do the three minerals of economic interest, i.e. magnetite, hydroxylapatite, and baddeleyite. The content of Sr, rare earth elements (REEs), and Ba in hydroxylapatite tends to increase gradually at the expense of Si, Fe, and Mg from early apatite-forsterite phoscorite (margins of the pipe) through carbonate-free, magnetite-rich phoscorite to carbonate-rich phoscorite and phoscorite-related carbonatite (inner part). Magnetite displays a trend of increasing V and Ca and decreasing Ti, Mn, Si, Cr, Sc, and Zn from the margins to the central part of the pipe; its grain size initially increases from the wall rocks to the inner part and then decreases towards the central part; characteristic inclusions in magnetite are geikielite within the marginal zone of the phoscorite-carbonatite pipe, spinel within the intermediate zone, and ilmenite within the inner zone. The zoning pattern seems to have formed due to both cooling and rapid degassing (pressure drop) of a fluid-rich magmatic column and subsequent pneumatolytic and hydrothermal processes.
DS201604-0611
2016
Yakovenchuk, V.N.Ivanyuk, G.Yu., Kalashnikov, A.O., Pakhomovsky, Ya.A., Mikhailov, J.A., Yakovenchuk, V.N., Konopleva, N.G., Sokharev, V.A., Bazai, A.V., Goryainov, P.M.Economic minerals of the Kovdor baddeleyite apatite magnetite deposit, Russia: mineralogy, spatial distribution and ore processing optimization.Ore Geology Reviews, in press available 73p.RussiaDeposit - Kovdor

Abstract: The comprehensive petrographical, petrochemical and mineralogical study of the Kovdor magnetite-apatite-baddeleyite deposit in the phoscorite-carbonatite complex (Murmansk Region, Russia) revealed a spatial distribution of grain size and chemical composition of three economically extractable minerals — magnetite, apatite, and baddeleyite, showing that zonal distribution of mineral properties mimics both concentric and vertical zonation of the carbonatite-phoscorite pipe. The marginal zone of the pipe consists of (apatite)-forsterite phoscorite carrying fine grains of Ti-Mn-Si-rich magnetite with ilmenite exsolution lamellae, fine grains of Fe-Mg-rich apatite and finest grains of baddeleyite, enriched in Mg, Fe, Si and Mn. The intermediate zone accommodates carbonate-free magnetite-rich phoscorites that carry medium to coarse grains of Mg-Al-rich magnetite with exsolution inclusions of spinel, medium-grained pure apatite and baddeleyite. The axial zone hosts carbonate-rich phoscorites and phoscorite-related carbonatites bearing medium-grained Ti-V-Ca-rich magnetite with exsolution inclusions of geikielite-ilmenite, fine grains of Ba-Sr-Ln-rich apatite and comparatively large grains of baddeleyite, enriched in Hf, Ta, Nb and Sc. The collected data enable us to predict such important mineralogical characteristics of the multicomponent ore as chemical composition and grain size of economic and associated minerals, presence of contaminating inclusions, etc. We have identified potential areas of maximum concentration of such by-products as scandium, niobium and hafnium in baddeleyite and REEs in apatite.
DS201605-0847
2016
Yakovenchuk, V.N.Ivanyuk, G.Yu., Kalashnikov, A.O., Pakhomovsky, Ya.A., Mikhailova, J.A., Yakovenchuk, V.N., Konopleva, N.G., Sokharev, V.A., Bazai, A.V., Goryainov, P.M.Economic minerals of the Kovdor baddeleyite apatite magnetite deposit, Russia: mineralogy, spatial distribution and ore procesing optimization.Ore Geology Reviews, Vol. 77, pp. 279-311.RussiaCarbonatite, Kovdor

Abstract: The comprehensive petrographical, petrochemical and mineralogical study of the Kovdor magnetite-apatite-baddeleyite deposit in the phoscorite-carbonatite complex (Murmansk Region, Russia) revealed a spatial distribution of grain size and chemical composition of three economically extractable minerals — magnetite, apatite, and baddeleyite, showing that zonal distribution of mineral properties mimics both concentric and vertical zonation of the carbonatite-phoscorite pipe. The marginal zone of the pipe consists of (apatite)-forsterite phoscorite carrying fine grains of Ti-Mn-Si-rich magnetite with ilmenite exsolution lamellae, fine grains of Fe-Mg-rich apatite and finest grains of baddeleyite, enriched in Mg, Fe, Si and Mn. The intermediate zone accommodates carbonate-free magnetite-rich phoscorites that carry medium to coarse grains of Mg-Al-rich magnetite with exsolution inclusions of spinel, medium-grained pure apatite and baddeleyite. The axial zone hosts carbonate-rich phoscorites and phoscorite-related carbonatites bearing medium-grained Ti-V-Ca-rich magnetite with exsolution inclusions of geikielite-ilmenite, fine grains of Ba-Sr-Ln-rich apatite and comparatively large grains of baddeleyite, enriched in Hf, Ta, Nb and Sc. The collected data enable us to predict such important mineralogical characteristics of the multicomponent ore as chemical composition and grain size of economic and associated minerals, presence of contaminating inclusions, etc. We have identified potential areas of maximum concentration of such by-products as scandium, niobium and hafnium in baddeleyite and REEs in apatite.
DS201608-1413
2016
Yakovenchuk, V.N.Ivanyuk, G.Yu., Kalashnikov, A.O., Pakhomovsky, Ya.A., Mikhailova, J.A., Yakovenchuk, V.N., Konopleva, N.G., Sokharev, V.A., Bazai, A.V., Goryainov, P.M.Economic minerals of the Kovdor baddeleyite apatite magnetite deposit, Russia: mineralogy, spatial distribution and ore processing optimization.Ore Geology Reviews, Vol. 77, pp. 279-311.RussiaDeposit - Kovdor

Abstract: The comprehensive petrographical, petrochemical and mineralogical study of the Kovdor magnetite-apatite-baddeleyite deposit in the phoscorite-carbonatite complex (Murmansk Region, Russia) revealed a spatial distribution of grain size and chemical composition of three economically extractable minerals — magnetite, apatite, and baddeleyite, showing that zonal distribution of mineral properties mimics both concentric and vertical zonation of the carbonatite-phoscorite pipe.The marginal zone of the pipe consists of (apatite)-forsterite phoscorite carrying fine grains of Ti-Mn-Si-rich magnetite with ilmenite exsolution lamellae, fine grains of Fe-Mg-rich apatite and finest grains of baddeleyite, enriched in Mg, Fe, Si and Mn. The intermediate zone accommodates carbonate-free magnetite-rich phoscorites that carry medium to coarse grains of Mg-Al-rich magnetite with exsolution inclusions of spinel, medium-grained pure apatite and baddeleyite. The axial zone hosts carbonate-rich phoscorites and phoscorite-related carbonatites bearing medium-grained Ti-V-Ca-rich magnetite with exsolution inclusions of geikielite-ilmenite, fine grains of Ba-Sr-Ln-rich apatite and comparatively large grains of baddeleyite, enriched in Hf, Ta, Nb and Sc. The collected data enable us to predict such important mineralogical characteristics of the multicomponent ore as chemical composition and grain size of economic and associated minerals, presence of contaminating inclusions, etc. We have identified potential areas of maximum concentration of such by-products as scandium, niobium and hafnium in baddeleyite and REEs in apatite.
DS201703-0429
2017
Yakovenchuk, V.N.Popova, E., Lushnikov, S.G., Yakovenchuk, V.N.The crystal structure of loparite: a new acentric variety.Mineralogy and Petrology, in press availablePerovskite, REE

Abstract: The crystal structure of the cubic modification of the natural mineral loparite has been studied for the first time by the methods of the X-ray diffraction analysis (?MoK ? radiation, 105 independent reflections with I > 3?(I), R = 0.041 in the anisotropic approximation). The structure belongs to the perovskite type (ABO 3) with the double period of the cubic unit cell, a = 7.767(1) Å (sp. gr. Pn3m; Z = 2 for the composition (Ca,Na,Ce)(Na,Ce)3(Ti,Nb)2Ti2O12. Period doubling is explained by ordering of cations both in the A and the B positions.
DS201801-0049
2017
Yakovenchuk, V.N.Popova, E.A., Lushnikov, S.G., Yakovenchuk, V.N., Krivovichev, S.V.The crystal structure of loparite: a new acentric variety.Mineralogy and Petrology, Vol. 111, pp. 827-832.Russia, Kola Peninsuladeposit - Khibiny

Abstract: The crystal structure of a new structural variety of loparite (Na0.56Ce0.21La0.14Ca0.06Sr0.03Nd0.02Pr0.01)?=1.03(Ti0.83Nb0.15)?=0.98O3 from the Khibiny alkaline massif, Kola peninsula, Russia, was solved by direct methods and refined to R1 = 0.029 for 492 unique observed reflections with I > 2?(I). The mineral is orthorhombic, Ima2, a = 5.5129(2), b = 5.5129(2) and c = 7.7874(5) Å. Similarly to other perovskite-group minerals with the general formula ABO3, the crystal structure of loparite is based upon a three-dimensional framework of distorted corner-sharing BO6. The A cations are coordinated by 12 oxygen atoms and are situated in distorted cuboctahedral cavities. In contrast to the ideal perovskite-type structure (Pm3?m), the unit cell is doubled along the c axis and the a and b axes are rotated in the ab plane at 45o. The BO6 octahedron displays distortion characteristic for the d0 transition metal cations with the out-of-center shift of the B site. The symmetry reduction is also attributable to the distortion of the BO6 octahedra which are tilted and rotated with respect to the c axis. The occurrence of a new acentric variety of loparite can be explained by the pecularities of its chemical composition characterized by the increased content of Ti compared to the previously studied samples.
DS201803-0487
2018
Yakovenchuk, V.N.Yakovenchuk, V.N., Yu, G., Pakhomovsky, Y.A., Panikorovskii, T.L., Britvin, S.N., Krivivichev, S.V., Shilovskikh, V.V., Bocharov, V.N.Kampelite, Ba3Mg1.5,Sc4(PO4)6(OH)3.4H2O, a new very complex Ba-Sc phosphate mineral from the Kovdor phoscorite-carbonatite complex ( Kola Peninsula) Russia.Mineralogy and Petrology, Vol. 112, pp. 111-121.Russia, Kola Peninsulacarbonatite - Kovdor
DS201808-1799
2018
Yakovenchuk, V.N.Zhitova, E.S., Krivocichev, S.V., Yakovenchuk, V.N., Ivanyuk, G.Y., Pakhomovsky, Y.A., Mikhailova, J.A.Crystal chemistry of natural layered double hydroxides: 4. Crystal structures and evolution of structural complexity of quintinite polytypes from the Kovdor alkaline ultrabasic massif, Kola Peninsula, Russia.Mineralogical Magazine, Vol. 82, no. 2, pp. 329-346.Russia, Kola Peninsuladeposit - Kovdor

Abstract: Two quintinite polytypes, 3R and 2T, which are new for the Kovdor alkaline-ultrabasic complex, have been structurally characterized. The crystal structure of quintinite-2T was solved by direct methods and refined to R1 = 0.048 on the basis of 330 unique reflections. The structure is trigonal, P c1, a = 5.2720(6), c = 15.113(3) Å and V = 363.76(8) Å3. The crystal structure consists of [Mg2Al(OH)6]+ brucite-type layers with an ordered distribution of Mg2+ and Al3+ cations according to the × superstructure with the layers stacked according to a hexagonal type. The complete layer stacking sequence can be described as …=Ab1C = Cb1A=…. The crystal structure of quintinite-3R was solved by direct methods and refined to R1 = 0.022 on the basis of 140 unique reflections. It is trigonal, R m, a = 3.063(1), c = 22.674(9) Å and V = 184.2(1) Å3. The crystal structure is based upon double hydroxide layers [M2+,3+(OH)2] with disordered distribution of Mg, Al and Fe and with the layers stacked according to a rhombohedral type. The stacking sequence of layers can be expressed as …=?B = BC = CA=… The study of morphologically different quintinite generations grown on one another detected the following natural sequence of polytype formation: 2H ? 2T ? 1M that can be attributed to a decrease of temperature during crystallization. According to the information-based approach to structural complexity, this sequence corresponds to the increasing structural information per atom (IG): 1.522 ? 1.706 ? 2.440 bits, respectively. As the IG value contributes negatively to the configurational entropy of crystalline solids, the evolution of polytypic modifications during crystallization corresponds to the decreasing configurational entropy. This is in agreement with the general principle that decreasing temperature corresponds to the appearance of more complex structures.
DS201905-1046
2019
Yakovenchuk, V.N.Ivanyuk, G.Y., Yakovenchuk, V.N., Panikorovskii, T.L., Konoplyova, N., Pakhomovsky, Y.A., Bazai, A.V., Bocharov, V.N., Krivovichev, S.V.Hydroxynatropyrochlore, ( Na, Ca, Ce)2 Nb2O6(OH), a new member of the pyrochlore group from the Kovdor phoscorite-carbonatite pipe, Kola Peninsula, Russia.Mineralogical Magazine, Vol. 83, pp. 107-113.Russia, Kola Peninsulacarbonatite

Abstract: Hydroxynatropyrochlore, (Na,?a,Ce)2Nb2O6(OH), is a new Na-Nb-OH-dominant member of the pyrochlore supergroup from the Kovdor phoscorite-carbonatite pipe (Kola Peninsula, Russia). It is cubic, Fd-3m, a = 10.3211(3) Å, V = 1099.46 (8) Å3, Z = 8 (from powder diffraction data) or a = 10.3276(5) Å, V = 1101.5(2) Å3, Z = 8 (from single-crystal diffraction data). Hydroxynatropyrochlore is a characteristic accessory mineral of low-carbonate phoscorite of the contact zone of the phoscorite-carbonatite pipe with host foidolite as well as of carbonate-rich phoscorite and carbonatite of the pipe axial zone. It usually forms zonal cubic or cubooctahedral crystals (up to 0.5 mm in diameter) with irregularly shaped relics of amorphous U-Ta-rich hydroxykenopyrochlore inside. Characteristic associated minerals include rockforming calcite, dolomite, forsterite, hydroxylapatite, magnetite,and phlogopite, accessory baddeleyite, baryte, barytocalcite, chalcopyrite, chamosite-clinochlore, galena, gladiusite, juonniite, ilmenite, magnesite, pyrite, pyrrhotite, quintinite, spinel, strontianite, valleriite, and zirconolite. Hydroxynatropyrochlore is pale-brown, with an adamantine to greasy lustre and a white streak. The cleavage is average on {111}, the fracture is conchoidal. Mohs hardness is about 5. In transmitted light, the mineral is light brown, isotropic, n = 2.10(5) (??= 589 nm). The calculated and measured densities are 4.77 and 4.60(5) g•cm-3, respectively. The mean chemical composition determined by electron microprobe is: F 0.05, Na2O 7.97, CaO 10.38, TiO2 4.71, FeO 0.42, Nb2O5 56.44, Ce2O3 3.56, Ta2O5 4.73, ThO2 5.73, UO2 3.66, total 97.65 wt. %. The empirical formula calculated on the basis of Nb+Ta+Ti = 2 apfu is (Na1.02Ca0.73Ce0.09Th0.09 U0.05Fe2+0.02)?2.00 (Nb1.68Ti0.23Ta0.09)?2.00O6.03(OH1.04F0.01)?1.05. The simplified formula is (Na, Ca,Ce)2Nb2O6(OH). The mineral slowly dissolves in hot HCl. The strongest X-ray powderdiffraction lines [listed as (d in Å)(I)(hkl)] are as follows: 5.96(47)(111), 3.110(30)(311), 2.580(100)(222), 2.368(19)(400), 1.9875(6)(333), 1.8257(25)(440) and 1.5561(14)(622). The crystal structure of hydroxynatropyrochlore was refined to R1 = 0.026 on the basis of 1819 unique observed reflections. The mineral belongs to the pyrochlore structure type A2B2O6Y1 with octahedral framework of corner-sharing BO6 octahedra with A cations and OH groups in the interstices. The Raman spectrum of hydroxynatropyrochlore contains characteristic bands of the lattice, BO6, B-O and O-H vibrations and no characteristic bands of the H2O vibrations. Within the Kovdor phoscorite-carbonatite pipe, hydroxynatropyrochlore is the latest hydrothermal mineral of the pyrochlore supergroup, which forms external rims around grains of earlier U-rich hydroxykenopyrochlore and separated crystals in voids of dolomite carbonatite veins. The mineral is named in accordance with the pyrochlore supergroup nomenclature.
DS201912-2795
2019
Yakovenchuk, V.N.Krivovichev, S.V., Yakovenchuk, V.N., Panikorovskii, T.L., Savchenko, E.E., Pakhailova, Yu, A., Selivanova, E.A., Kadyrova, G.I., Ivanyuk, G.Yu.,Krivovchev, S.V.Nikmelnikovite: Ca 12 Fe 2+ Fe 3+3 Al3(SiO4) 6(OH)20: a new mineral from the Kovdor Massif ( Kola Peninsula, Russia)Doklady Earth Sciences, Vol. 488, 2, pp. 1200-1202.Russia, Kola Peninsuladeposit - Kovdor
DS1990-1604
1990
Yakovlev, B.G.Yakovlev, B.G., Matsyuk, S.S., Vishnevskiy, A.A., Chubarov, V.M.Evolution of mineral equilibration temperatures and petrogenesis of the deep mafic ferruginous granulites from Yakutian kimberlite pipes.(Russian)Mineral. Zhurn., (Russian), Vol. 12, No. 4, August pp. 3-15RussiaPetrology, Mineral chemistry
DS201412-0897
2014
Yakovlev, D.Sun, J., Liu, C-Z., Tappe, S., Kostrovitsky, S.I., Wu, F-Y., Yakovlev, D., Yang, Y-H., Yang, J-H.Repeated kimberlite magmatism beneath Yakutia and its relationship to Siberian flood volcanism: insights from in situ U-Pb and Sr-Nd perovskite isotope analysis.Earth and Planetary Science Letters, Vol. 404, Oct. pp. 283-295.Russia, YakutiaKimberlite magmatism
DS200712-0575
2007
Yakovlev, D.A.Kostrovitsky, S.I., Morikyo, T., Serov, I.V., Yakovlev, D.A., Amirzhanov, A.A.Isotope geochemical systematics of kimberlites and related rocks from the Siberian Platform.Russian Geology and Geophysics, Vol. 48, pp. 272-290.RussiaGeochronology
DS200812-1285
2008
Yakovlev, D.A.Yakovlev, D.A., Kostrovitsky, S.I., Alymova, N.V.Mineral composition features from the Upper Muna field, Yakutia.9IKC.com, 3p. extended abstractRussia, YakutiaMineral chemistry - Verhknemunsk
DS201312-0509
2013
Yakovlev, D.A.Kostrovitsky, S.I., Soloveva, L.V., Yakovlev, D.A., Suvorova, L.F., Sandimirova, G.P., Travin, A.V., Yudin, D.S.Kimberlites and megacrystic suite: isotope geochemical studies.Petrology, Vol. 21, 2, pp. 127-144.Russia, YakutiaDeposit - Udachnaya
DS201609-1726
2016
Yakovlev, D.A.Kopylova, M.G., Gaudet, M., Kostrovitsky, S.I., Polozov, A.G., Yakovlev, D.A.Origin of salts and alkali carbonates in the Udachnaya East kimberlite: insights from petrography of kimberlite phases and their carbonate and evaporite xenoliths.Journal of Volcanology and Geothermal Research, in press available 19p.RussiaDeposit - Udachnaya East

Abstract: The Udachnaya East kimberlite is characterized by the presence of chlorides, sulfates and alkali carbonates. This highly atypical mineralogy underpinned a model for an anhydrous alkali-rich primary kimberlite melt, despite the absence of petrographic studies providing textural context to the exotic minerals. The present work documents the petrography of the Udachnaya East kimberlite in order to address this problem. The pipe comprises two varieties of Fort-a-la-Corne type pyroclastic kimberlite, olivine-rich and magmaclast-rich, and coherent kimberlite. These kimberlites entrain xenoliths of limestones, altered shales and siltstones, halite-dominated rocks, dolomites, and coarse calcite rocks. The distinct varieties of the Udachnaya East kimberlite carry different populations of crustal xenoliths, which partially control the mineralogy of the host kimberlite. In magmaclast-rich pyroclastic kimberlite, where halite is absent from the crustal xenoliths, it is not observed in the interclast matrix, or within the magmaclasts. Halite occurs in the interclast matrix of olivine-rich pyroclastic kimberlite, where halite xenoliths are common. Large, ~ 30 cm halite xenoliths are uniquely restricted to the coherent kimberlite and show a strong reaction with it. The halite xenoliths are sourced from depths of ? 1500 to ? 630 m, where carbonate beds host multiple karst cavities filled with halite and gypsum and occasional sedimentary evaporites. The style of secondary mineralization at Udachnaya depends on whether the kimberlite is coherent or pyroclastic. Shortite, pirssonite and other alkali carbonates replacing calcite and possibly serpentine are abundant only in porous pyroclastic kimberlites of both types and in their shale/siltstone xenoliths. The lower porosity of the coherent kimberlite prevented the interaction of kimberlite with Na brines. Serpentinization localized around halite xenoliths started at temperatures above 500 °C, as indicated by its association with high-temperature iowaite. The model of the “dry” Na and Cl-rich primary kimberlite melt is invalidated on the basis of 1) the restriction of exotic salt minerals to certain kimberlite types and xenoliths; and 2) the absence of halite-rich melt inclusions in olivine of coherent kimberlite.
DS201710-2266
2017
Yakovlev, D.A.Sobolev, N.V., Schertle, H-P., Neuser, R.D., Tomilenko, A.A., Kuzmin, D.V., Loginova, A.M., Tolstov, A.V., Kostrovitsky, S.I., Yakovlev, D.A., Oleinikov, O.B.Formation and evolution of hypabyssal kimberlites from the Siberian craton: part 1 - new insights from cathodluminescence of the carbonates. Anabar and Olenek areaJournal of Asian Earth Sciences, Vol. 145, pt. B, pp. 670-678.Russia, Siberiadeposit - Kuranakh, Kharamay
DS202202-0225
2022
Yakovlev, D.A.Yakovlev, D.A., Kostrovistsky, S.I., Fosu, B.R., Ashchepkov, I.V.Diamondiferous kimberlites from recently explored Upper Muna field ( Siberian craton): petrology, mineralogy and geochemistry insights,Geological Society of London Special Publication 513, pp. 71-102.Russia, Siberiadeposit - Muna

Abstract: Petrographic, geochemical and mineralogical characteristics of diamond deposits from the Upper Muna field have been investigated. Geochemically, diamondiferous kimberlites from Upper Muna belong to the most widespread Fe-Mg-rich rocks in the Yakutian kimberlite province (average FeOtotal = 8.4 wt%, MgO = 32.36 wt%, TiO2 = 1.6 wt%). Striking mineralogical features of Upper Muna kimberlites are: (1) abundance of monticellite and perovskite in the groundmass; (2) rare occurrence of Mg-ilmenite; (3) abundance of phlogopite megacrysts (up to 8 cm across); and (4) coexistence of low-Cr (0.1-4 wt% Cr2O3, with 0.8-1.2 wt% TiO2) and high-Cr (3-8 wt% Cr2O3, with 0.1-0.6 wt% TiO2) garnet megacrysts with contrasting rare earth element patterns. The compositional features of groundmass minerals, the relatively low CaO and CO2 contents in kimberlites and few deuteric alteration in Upper Muna kimberlites suggest high-temperature melt crystallization during pipe emplacement. Based on the compositional data of garnet and Cr-diopside from megacrysts and peridotites, we suggest a poor Cr dunite-harzburgitic and lherzolitic mantle source beneath the Upper Muna field where Cr-diopside crystallized within a wide pressure and temperature range (40-65 kbar and 900-1350°?). The mineral geochemistry, trace element distribution and Sr-Nd isotope variations of Upper Muna kimberlites are typical for group I kimberlites and reflect a deep-seated asthenospheric (convective mantle) source for the kimberlites.
DS202203-0373
2022
Yakovlev, D.A.Yakovlev, D.A., Kostrovistsky, S.I., Fosu, B.R., Ashchepkov, I.V.Diamondiferous kimberlites from recently explored Upper Muna field ( Siberian craton): petrology, mineralogy and geochemistry insights,Geological Society of London Special Publication 513, pp. 71-102.Russia, Siberiadeposit - Muna

Abstract: Petrographic, geochemical and mineralogical characteristics of diamond deposits from the Upper Muna field have been investigated. Geochemically, diamondiferous kimberlites from Upper Muna belong to the most widespread Fe-Mg-rich rocks in the Yakutian kimberlite province (average FeOtotal = 8.4 wt%, MgO = 32.36 wt%, TiO2 = 1.6 wt%). Striking mineralogical features of Upper Muna kimberlites are: (1) abundance of monticellite and perovskite in the groundmass; (2) rare occurrence of Mg-ilmenite; (3) abundance of phlogopite megacrysts (up to 8 cm across); and (4) coexistence of low-Cr (0.1-4 wt% Cr2O3, with 0.8-1.2 wt% TiO2) and high-Cr (3-8 wt% Cr2O3, with 0.1-0.6 wt% TiO2) garnet megacrysts with contrasting rare earth element patterns. The compositional features of groundmass minerals, the relatively low CaO and CO2 contents in kimberlites and few deuteric alteration in Upper Muna kimberlites suggest high-temperature melt crystallization during pipe emplacement. Based on the compositional data of garnet and Cr-diopside from megacrysts and peridotites, we suggest a poor Cr dunite-harzburgitic and lherzolitic mantle source beneath the Upper Muna field where Cr-diopside crystallized within a wide pressure and temperature range (40-65 kbar and 900-1350°?). The mineral geochemistry, trace element distribution and Sr-Nd isotope variations of Upper Muna kimberlites are typical for group I kimberlites and reflect a deep-seated asthenospheric (convective mantle) source for the kimberlites.
DS202111-1793
2021
Yakovlev, E.Yakovlev, E., Puchkov, A.Radon over kimberlite pipes: estimation of the emanation properties of rocks ( Lomonosov diamond deposit, NW Russia).MDPI Applied Sciences, Vol. 11, 6065, 22p. PdfRussia, Arkangelskdeposit - Lomonosov

Abstract: In this paper, using the example of the Lomonosov diamond deposit, experimental studies of rocks were carried out to assess the main radiation and physical factors affecting the formation of the radon field over the kimberlite pipes of the Arkhangelsk diamondiferous province. For various types of rocks, represented by vent kimberlites, tuffaceous-sedimentary rocks of the crater and enclosing and overlying sediments, the following were studied: porosity, density, activity of radium-226, activity of radon in a free state, level of radon production, and emanation coefficient. The research results showed that the greatest amount of radon in a free state is produced by rocks of the near-pipe space, represented by the enclosing Vendian V2 deposits and characterized by high values of the emanation coefficient, radium activity, radon production level and porosity. This fact is associated with the structural and geological features of the near-pipe space, which was exposed to the impact of kimberlite magma on the host rocks. The lowest values of these parameters are characteristic of the kimberlites of the vent facies, which limits the formation of free radon in the body of the pipe. The results of the experimental studies create prospects for the development of emanation methods for searching for kimberlite pipes in the conditions of the Arkhangelsk diamondiferous province.
DS202112-1925
2021
Yakovlev, E.Danilov, K., Yakovlev, E., Afonin, N.Study of deep structure of the kimberlite pipe named after M. Lomonosov of the Arkhangelsk diamondiferous province obtained by joint using of passive seismic and radiometric methods.Pure and Applied Geophysics, Vol. 178, 10, pp, 3933-3952.Russia, Arkangelskdeposit - Lomonsov

Abstract: Kimberlite pipes are difficult to investigate due to their vertical orientation, conic shape and diverse physical characteristics and petrological compositions, all of which obstruct the use of magnetic methods, reflection and refraction seismic surveys to examine kimberlite pipes. Wherein the emplacement model for kimberlite pipes has important significance in resource geology and in mine design process. As a result, the development of new methods of investigating kimberlite pipes remains necessary. To that end, because the most stable characteristic of kimberlite pipes is their downward-tapering structure, the pipes can be more effectively examined by using methods offering high resolution and new indicators for prospecting. Herein, we present the results of jointly using passive seismic and radiometric methods to study the structure of a kimberlite pipe and its enclosing environment. In particular, we employed a microseismic sounding method, passive seismic interferometry, the H/V method, gamma spectrometry and emanation mapping to model the kimberlite pipe named after M. Lomonosov of the Arkhangelsk diamondiferous province. The combined use of those methods revealed an ore-controlled fault and probably a supply channel (i.e. dyke). The obtained model is correspondent to drill whole data and includes additional information about the structure and elastic properties of the studied pipe. Amongst its principal benefits, the proposed technique affords the possibility of discerning the primary elements of the kimberlite pipes and enclosing environments at depths from 30 m to 2 km, which can significantly increase the effectiveness of investigations into kimberlite pipes.
DS1985-0747
1985
Yakovlev, E.N.Yakovlev, E.N., Shalimov, M.D., Kulikova, L.F., Slesarev, V.N.Synthesis of Diamond from HydrocarbonsZhurn. Fiz. Khim., Vol. 59, No. 6, PP. 1517-1519.RussiaDiamond Crystallography, Morphology
DS1985-0748
1985
Yakovlev, E.N.Yakovlev, E.N., Shalimov, M.D., Kulikova, L.F., Slesarev, V.N.Synthesis of Diamonds from CarbohydratesZhurn. Fiz. Khim., Vol. 59, No. 6, JUNE PP. 1517-1518.RussiaDiamond Sythetic
DS1987-0820
1987
Yakovlev, E.N.Yakovlev, E.N., Voronov, O.A., Rakhmanina, A.V.Polycrystalline diamond aggregates obtained by using hydrocarbons.(Russian)Sverktverd. Mater.(Russian), No. 2, pp. 3-5GlobalDiamond synthesis
DS1999-0577
1999
Yakovlev, E.N.Rakhmania, A.V., Yakovlev, E.N.Experimental modeling of the natural synthesis of polycrystalline diamondGeochemistry International, Vol. 37, No. 7, July pp. 678-82.GlobalDiamond morphology
DS201802-0245
2017
Yakovlev, E.Yu.Kiselev, G.P., Yakovlev, E.Yu., Druzhinin, S.V., Galkin, A.S.Distribution of radioactive isotopes in rock and ore of Arkhanelskava pipe from the Arkhanelsk diamond province.Geology of Ore Deposits, Vol. 59, pp. 391-406.Russia, Archangeldeposit - Arkhangelskaya

Abstract: The contents of radioactive elements and the uranium isotopic composition of kimberlite in the Arkhangelskaya pipe at the M.V. Lomonosov deposit and of nearby country rocks have been studied. A surplus of 234U isotope has been established in rocks from the near-pipe space. The high ? = 234U/238U ratio is controlled by the geological structure of the near-pipe space. A nonequilibrium uranium halo reaches two pipe diameters in size and can be regarded as a local ore guide for kimberlite discovery. The rocks in the nearpipe space are also characterized by elevated or anomalous U, Th, and K contents with respect to the background.
DS202009-1675
2020
Yakovlev, E.Yu.Yakovlev, E.Yu.Features of radioactive element distribution within the Arkhangelsk diamondiferous province: possible directions for development of isotope-radiogeochemical methods for kimberlite prospecting in complex landscape geology and climate conditions of the subaGeochemistry: Exploration, Environment, Analysis, Vol. 20, pp. 269-279. pdfRussia, Arkangelgeochemisty
DS202004-0532
2020
Yakovlev, G.A.Sharygin, V.V., Britvin, S.N., Kaminsky, F.V., Wirth, R., Nigmatulina, E.N., Yakovlev, G.A., Novoselov, K.A., Murashko, M.N.Ellinaite IMA No. 2019-091 mineral name( gravel of Sorriso creek, Aripuna River).European Journal of Mineralogy, Vol. 32, p. 211.Europe, Israel, South America, Brazil, Mato Grossodiamond inclusion
DS202010-1841
2020
Yakovlev, I.Dymshits, A., Sharygin, I., Liu, Z., Korolev, N., Malkovets, V., Alifirova, T., Yakovlev, I., Xu, Y-G.Oxidation state of the lithospheric mantle beneath Komosomolskaya-Magnitnaya kimberlite pipe, Upper Muna field, Siberian craton.Minerals, Vol. 10, 9, 740 10.3390/ min10090740 24p. PdfRussiadeposit - Muna

Abstract: The oxidation state of the mantle plays an important role in many chemical and physical processes, including magma genesis, the speciation of volatiles, metasomatism and the evolution of the Earth’s atmosphere. We report the first data on the redox state of the subcontinental lithospheric mantle (SCLM) beneath the Komsomolskaya-Magnitnaya kimberlite pipe (KM), Upper Muna field, central Siberian craton. The oxygen fugacity of the KM peridotites ranges from ?2.6 to 0.3 logarithmic units relative to the fayalite-magnetite-quartz buffer (?logfO2 (FMQ)) at depths of 120-220 km. The enriched KM peridotites are more oxidized (?1.0-0.3 ?logfO2 (FMQ)) than the depleted ones (from ?1.4 to ?2.6 ?logfO2 (FMQ)). The oxygen fugacity of some enriched samples may reflect equilibrium with carbonate or carbonate-bearing melts at depths >170 km. A comparison of well-studied coeval Udachnaya and KM peridotites revealed similar redox conditions in the SCLM of the Siberian craton beneath these pipes. Nevertheless, Udachnaya peridotites show wider variations in oxygen fugacity (?4.95-0.23 ?logfO2 (FMQ)). This indicates the presence of more reduced mantle domains in the Udachnaya SCLM. In turn, the established difference in the redox conditions is a good explanation for the lower amounts of resorbed diamonds in the Udachnaya pipe (12%) in comparison with the KM kimberlites (33%). The obtained results advocate a lateral heterogeneity in the oxidation state of the Siberian SCLM.
DS202010-1840
2020
Yakovlev, I.V.Dymshits, A., Sharygin, I., Malkovets, V., Yakovlev, I.V., Gibsher, A.A., Alifirova, T.A., Vorobei, S.S., Potapov, S.V., Garanin, V.K.Thermal state, thickness and composition of the lithospheric mantle beneath the Upper Muna kimberlite field, Siberian Craton, constrained by clinopyroxene xenocrysts and comparison with Daldyn and Mirny fields.Minerals, 10.1039/DOJA00308E 20p. PdfRussiadeposit - Muna

Abstract: To gain better insight into the thermal state and composition of the lithospheric mantle beneath the Upper Muna kimberlite field (Siberian craton), a suite of 323 clinopyroxene xenocrysts and 10 mantle xenoliths from the Komsomolskaya-Magnitnaya (KM) pipe have been studied. We selected 188 clinopyroxene grains suitable for precise pressure (P)-temperature (T) estimation using single-clinopyroxene thermobarometry. The majority of P-T points lie along a narrow, elongated field in P-T space with a cluster of high-T and high-P points above 1300 °C, which deviates from the main P-T trend. The latter points may record a thermal event associated with kimberlite magmatism (a “stepped” or “kinked” geotherm). In order to eliminate these factors, the steady-state mantle paleogeotherm for the KM pipe at the time of initiation of kimberlite magmatism (Late Devonian-Early Carboniferous) was constrained by numerical fitting of P-T points below T = 1200 °C. The obtained mantle paleogeotherm is similar to the one from the nearby Novinka pipe, corresponding to a ~34-35 mW/m2 surface heat flux, 225-230 km lithospheric thickness, and 110-120 thick "diamond window" for the Upper Muna field. Coarse peridotite xenoliths are consistent in their P-T estimates with the steady-state mantle paleogeotherm derived from clinopyroxene xenocrysts, whereas porphyroclastic ones plot within the cluster of high-T and high-P clinopyroxene xenocrysts. Discrimination using Cr2O3 demonstrates that peridotitic clinopyroxene xenocrysts are prevalent (89%) among all studied 323 xenocrysts, suggesting that the Upper Muna mantle is predominantly composed of peridotites. Clinopyroxene-poor or -free peridotitic rocks such as harzburgites and dunites may be evident at depths of 140-180 km in the Upper Muna mantle. Judging solely from the thermal considerations and the thickness of the lithosphere, the KM and Novinka pipes should have excellent diamond potential. However, all pipes in the Upper Muna field have low diamond grades (<0.9, in carats/ton), although the lithosphere thickness is almost similar to the values obtained for the high-grade Udachnaya and Mir pipes from the Daldyn and Mirny fields, respectively. Therefore, other factors have affected the diamond grade of the Upper Muna kimberlite field.
DS202104-0591
2021
Yakovlev, I.V.Malkovets, V.G., Shatsky, V.S., Dak, A.I., Gibsher, A.A., Yakovlev, I.V., Belousova, E.A., Tsujimori, T., Sobolev, N.V.Evidence for multistage and polychronous alkaline-ultrabasic Mesozoic magmatism in the area of diamondiferous placers of the Ebelyakh River basin, ( eastern slope of the Anabar shield).Doklady Earth Sciences, Vol. 496, 1, pp. 48-52.Russiadeposit - Anabar

Abstract: New mineralogical and isotope-geochemical data for zircon megacrysts (n = 48) from alluvium of Kholomolokh Creek (a tributary of the Ebelakh River) are reported. Using the geochemical classification schemes, the presence of zircons of kimberlitic and carbonatitic genesis was shown. The U-Pb dating of zircons revealed two major age populations: the Triassic (258-221 Ma, n = 18) and Jurassic (192-154 Ma, n = 30). Weighted mean 206Pb/238U ages allowed us to distinguish the following age stages: 155 ± 3, 161 ± 2, 177 ± 1.5, 183 ± 1.5, 190 ± 2, 233 ± 2.5, and 252 ± 4 Ma. It is suggested that the Ebelyakh diamonds could have been transported from the mantle depths by kimberlite, as well as by other related rocks, such as carbonatite, lamprophyre, lamproite, olivine melilitite, etc. Diamonds from the Ebelyakh placers most likely have polygenic native sources and may be associated with polychronous and multistage Middle Paleozoic and Mesozoic kimberlite and alkaline-ultrabasic magmatism in the eastern slope of the Anabar Shield (the Ebelyakh, Mayat, and Billyakh river basins).
DS1993-1787
1993
Yakovlev, L.Ye.Yakovlev, L.Ye.The role of metamorphism of the basaltic basement of sedimentary basins incrustal evolutionInternational Geology Review, Vol. 35, No. 1, January pp. 27-47RussiaTectonics, Basins
DS202007-1128
2020
Yakovlev, V.N.Chanturia, V.A., Dvoichenkova, G.P., Morozov, V.V., Kovalchuk, O.E., Pdkamennyi, Yu.A., Yakovlev, V.N.Selective attachment of luminophore bearing emulsion at diamonds - mechanism analysis and mode selection. X-rayJournal of Mining Science, Vol. 56, 1, pp. 96-103. pdfGloballuminescence

Abstract: The authors present an efficient modification method of X-ray fluorescence separation with mineral and organic luminophores used to adjust spectral and kinetic characteristics of anomalously luminescent diamonds. The mechanism of attachment of luminophores at diamonds and hydrophobic minerals is proved, including interaction between the organic component of emulsions and the hydrophobic surface of a treated object and the concentration of insoluble luminophore grains at the organic and water interface. Selective attachment of the luminophore-bearing organic phase of emulsion at the diamond surface is achieved owing to phosphatic dispersing agents. Tri-sodium phosphate and sodium hexametaphosphate added to emulsion reduce attachment of the luminophore-bearing organic phase at the surface of kimberlite minerals. It is shown that phosphate concentration of 1.0-1.5 g/l modifies and stabilizes spectral and kinematic parameters of kimberlite mineral on the level of initial values. This mode maintains the spectral and kinematic characteristics of anomalously luminescent diamonds at the wanted level to ensure extraction of diamonds to concentrate.
DS200512-0625
2005
YakovlevaLevchenkov, O.A., Gaidamako, I.M., Levskii, L.K., Komarov, Yakovleva, Rizvanova, MakeevU Pb age of zircon from the Mir and 325 Let Yakutii pipes.Doklady Earth Sciences, Vol. 400, 1, pp. 99-101.Russia, YakutiaGeochronology
DS200612-0189
2006
YakovlevaBuchko, I.V., Salnikova, E.B., Kotov, A.B., Larin, A.M., Velikoslavinskii, Sorokin, Sorokin, YakovlevaPaleoproterozoic gabbro anorthosites of the Selenga Superterrane, southern framing of the Siberian Craton.Doklady Earth Sciences, Vol. 407, 3, pp. 372-375.Russia, SiberiaTectonics
DS201212-0158
2012
YakovlevaDegtyarev, K.E., Tretyakov, Kotov, Salnikova, Shatagi, Yakovleva, Anismova, PlotkinaThe Chelkar peridotite-gabbronorite pluton ( Kokchetav massif, northern Kazakhstan): formation type and geochronology.Doklady Earth Sciences, Vol. 446, 2, pp. 1162-1166.Russia, KazakhstanGeochronlogy
DS201412-0473
2014
Yakovleva, S.Korikovsky, S., Kotov, A., Salnikova, E., Aranovich, L., Korpechkov, D., Yakovleva, S., Tolmacheva, E., Anisimova, I.The age of the protolith of metamorphic rocks in the southeastern Lapland granulite belt, southern Kola Peninsula: correlation with the Belomorian mobile belt in the context of the problem of Archean eclogites.Petrology, Vol. 22, 2, pp. 91-108.Russia, Kola PeninsulaEclogite
DS200712-0367
2006
Yakovleva, S.V.Golovkov, V.P., Yakovleva, S.V.Electric conductivity of the lower mantle. Methods and results.Geomagnetism and Aeronomy, American Geophysical Union, Vol. 46, 5, pp. 676-681.MantleGeophysics
DS201412-0952
2014
Yakovleva, S.Z.Vladykin, N.V., Kotov, A.B., Borisenko, A.S., Yarmolyuk, V.V., Pokhilenko, N.P., Salnikova, E.B., Travin, A.V., Yakovleva, S.Z.Age boundaries of formation of the Tomtor alkaline ultramafic pluton: U Pb and 40 Ar 39 Ar geochronological studies.Doklady Earth Sciences, Vol. 454, 1, pp. 7-11.RussiaGeochronology
DS201412-0953
2014
Yakovleva, S.Z.Vladykin, N.V., Sotnikov, I.A., Kotov, A.B., Yarmolyuk, V.V., Salnikova, E.B., Yakovleva, S.Z.Structure, age and ore potential of the Burpala rare-metal alkaline Massif, northern Baikal region.Geology of Ore Deposits, Vol. 56, 4, pp. 239-256.RussiaAlkalic
DS1990-1605
1990
Yakovleva, T.P.Yakovleva, T.P., Leskina, L.M., Matyukhin, V.V., Yampolskaya, E.G.Functional state and sickness rate of diamond processing workers. (Russian)Gig Tr Prof. Zabol., (russian), No. 8, pp. 38-42RussiaDiamond processing, Workers
DS202104-0611
2021
Yakovleva, V.V.Titkov, S.V., Yakovleva, V.V., Breev, I.D., Anisimov, A.N., Baranov, P.G., Dorofeeva, A.I., Bortnikov, N.S.Distribution of nitrogen-vacancy NV centers in cubic diamond crystals from Anabar placers as revealed by ODMR and PL tomography.Doklady Earth Sciences, Vol. 496, 1, pp. 45-47. pdfRussiadeposit - Anabar

Abstract: Nitrogen-vacancy NV- centers, which are of considerable interest for quantum electronics, are artificially produced in the diamond structure by irradiation and subsequent annealing. In this work, these centers were revealed in natural diamonds of cubic habit (type IaA + Ib according to physical classification) from an industrial placer deposit of the Anabar River (NE Siberian platform) using the method of optically detected magnetic resonance (ODMR). Localization of the NV- centers in the dislocations slip planes {111}, separated by distances of about 5 ?m, was established by means of scanning the ODMR and PL signals with a submicron resolution. In various crystals, one or two intersecting systems of such slip planes have been revealed. The largest amounts of these defects were found in the peripheral zones of crystals containing increased amounts of single isomorphic nitrogen atoms in the structure. The data obtained indicate the formation of the NV- centers in natural diamonds under post-crystallization plastic deformation, i.e., by a mechanism that differs from the widely used method of their artificial production.
DS2001-1274
2001
Yakubchuk, A.Yakubchuk, A., Seltmann, R., Shatov, V., Cole, A.The Altoids: tectonic evolution and metallogenySeg Newsletter, No. 46, July pp. 1, 7-14.Europe, Siberia, Russia, ChinaCraton, Tectonics
DS2002-1755
2002
Yakubchuk, A.Yakubchuk, A., Cole, A., Seltmann, R., Shatov, V.Tectonic setting, characteristics and regional exploration criteria for gold mineralization...Society of Economic Geologists Special Publication, No.9,pp.177-201.China, Tien ShanOrogeny - Altaid orogenic collage, key example, Deposit - lists
DS201012-0870
2010
Yakubchuk, A.Yakubchuk, A.Restoring the supercontinent Columbia and tracing its fragments after the breakup: a new configuration and Super-Horde hypothesis.Journal of Geodynamics, Vol. 50, 3-4, pp. 166-175.MantleCrustal evolution
DS200612-0574
2005
Yakubchuk, A.S.Herrington, R.J., Puchkov, V.N., Yakubchuk, A.S.A reassessment of the tectonic zonation of the Uralides: implications for metallogeny.Geological Society of London Special Paper, No. 248, pp. 153-166.RussiaTectonics
DS1975-0307
1976
Yakubova, S.A.Kolomiytsev, A.I., Yakubova, S.A.The Columnal Growth Mechanisms of Natural Cubic Diamond Crystals.Zap. Vses. Mineral. Obshch., No. 4, P. 72.RussiaCrystallography
DS1986-0722
1986
Yakubova, S.A.Semenova-Tyan-Shanakaya, A.S., Yakubova, S.A.Internal morphology and microhardness of natural diamond.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR (Russian), Vol. 286, No. 6, pp. 1491-1493RussiaBlank
DS1987-0661
1987
Yakubova, S.A.Semenova-Tyan-Shanskaya, A.S., Yakubova, S.A.Internal morphology and microhardness of natural diamondDokl. Acad. Sciences USSR Earth Science Section, Vol. 286, No. 1-6, September pp. 150-151RussiaBlank
DS2000-1036
2000
Yakubovich, O.V.Yakubovich, O.V., Massa, W., Liferovich, PakhomovskyThe crystal structure of bakhchisaraitsevite: hydrothermal origin from Kovdor phoscorite carbonatiteCanadian Mineralogist, Vol. 38, 4, Aug. pp. 831-8.RussiaCarbonatite, Deposit - Kovdor
DS201610-1889
2016
Yakubovich, O.V.Mochalov, A.G., Yakubovich, O.V., Bortnikov, N.S.190Pt-4He age of PGE ores in the alkaline ultramafic Kondyor Massif ( Khabarovsk district) Russia.Doklady Earth Sciences, Vol. 469, 2, pp. 846-850.RussiaAlkalic

Abstract: A new 190Pt-4He method for dating isoferroplatinum has been developed at the Institute of Precambrian Geology and Geochronology, Russian Academy of Sciences. Here we publish the first results of dating of isoferroplatinum from the main mineralogical and geochemical types of PGE mineralization in dunite. The obtained 190Pt-4He age of isoferroplatinum is 129 ± 6 Ma. The gained 190Pt-4He age of isoferroplatinum specimens of different genesis (magmatic, fluid-metamorphogenic, and metasomatic) from the Kondyor Massif indicates that the PGM mineralization took place synchronously and successively with evolution of primarily picrite, followed by subalkaline and alkaline melts of the Mesozoic tectonic-magmatic activation of the Aldan Shield.
DS1982-0647
1982
Yakubovskaya, N.YE.Yakubovskaya, N.YE., Ilupin, I.P.Magnetic Properties of Picroilmenite of Siberian KimberlitesMineral. Zhurn., No. 4, PT. 5, PP. 36-43.RussiaBlank
DS1999-0217
1999
Yakushev, A.I.Filmonova, L.G., Yakushev, A.I.Zonation in almondine garnets from eclogite microxenoliths indicator metamorphism subduction zone.Proceedings Russ. Min. Soc., *RUSS, Vol. 28, No. 1, pp. 54-62.MantleSubduction zone
DS1988-0671
1988
Yakushev, V.M.Storozhenko, L.E., Tsaur, G.I., Yakushev, V.M.Age and genesis of diamond bearing formations of Volynskii quarry (western slope of the Ural)technical note. (Russian)Izv. Akad Nauk SSSR, Ser. Geol., (Russian), No. 5, May pp. 131-133RussiaGeochronology, Volynskii
DS1992-1711
1992
YakutalmazYakutalmazColourful brochure of the operations and objectives of this associationYakutalmaz Association, Brochure handout by WGM at PDA 55p.Russia, Commonwealth of Independent States (CIS), YakutiaCompany brochure, Yakutalmaz
DS1993-1788
1993
Yakutin, V.E.Yakutin, V.E.Alluvial diamond deposits of western Yakutia: methods of evaluation andexploration.Diamonds of Yakutia, pp. 103-104.Russia, YakutiaAlluvials, Evaluation
DS202002-0187
2020
Yakymchuk, C.Gardiner, N.J., Kirkland, C.L., Hollis, J.A., Cawood, P.A., Nebel, O., Szilas, K., Yakymchuk, C.North Atlantic craton architecture revealed by kimberlite-hosted crustal zircons.Earth and Planetary Science Letters, Vol. 534, 8p. PdfEurope, Greenlandkimberlite genesis

Abstract: Archean cratons are composites of terranes formed at different times, juxtaposed during craton assembly. Cratons are underpinned by a deep lithospheric root, and models for the development of this cratonic lithosphere include both vertical and horizontal accretion. How different Archean terranes at the surface are reflected vertically within the lithosphere, which might inform on modes of formation, is poorly constrained. Kimberlites, which originate from significant depths within the upper mantle, sample cratonic interiors. The North Atlantic Craton, West Greenland, comprises Eoarchean and Mesoarchean gneiss terranes - the latter including the Akia Terrane - assembled during the late Archean. We report U-Pb and Hf isotopic, and trace element, data measured in zircon xenocrysts from a Neoproterozoic (557 Ma) kimberlite which intruded the Mesoarchean Akia Terrane. The zircon trace element profiles suggest they crystallized from evolved magmas, and their Eo-to Neoarchean U-Pb ages match the surrounding gneiss terranes, and highlight that magmatism was episodic. Zircon Hf isotope values lie within two crustal evolution trends: a Mesoarchean trend and an Eoarchean trend. The Eoarchean trend is anchored on 3.8 Ga orthogneiss, and includes 3.6-3.5 Ga, 2.7 and 2.5-2.4 Ga aged zircons. The Mesoarchean Akia Terrane may have been built upon mafic crust, in which case all zircons whose Hf isotopes lie within the Eoarchean trend were derived from the surrounding Eoarchean gneiss terranes, emplaced under the Akia Terrane after ca. 2.97 or 2.7 Ga, perhaps during late Archean terrane assembly. Kimberlite-hosted peridotite rhenium depletion model ages suggest a late Archean stabilization for the lithospheric mantle. The zircon data support a model of lithospheric growth via tectonic stacking for the North Atlantic Craton.
DS1860-0482
1885
Yale, C.G.Yale, C.G.California Diamonds, 1885West American Scientist., Vol. 2, P. 60.United States, CaliforniaDiamond Occurrence
DS1983-0637
1983
Yale, L.B.Yale, L.B.An Investigation of Serpentinization and RodingitizationMsc. Thesis, Stanford Univ, 113pGlobalBlank
DS1998-1608
1998
Yale, L.B.Yale, L.B., Carpenter, S.J.Large igneous provinces and giant dike swarms: proxies for supercontinent cyclicity and mantle convection.Earth and Planetary Science Letters, Vol. 163, No. 1-4, Nov. pp. 109-122.MantleSupercontinent cycle, Dike swarms
DS201811-2620
2015
Yaluma, C.B.Yaluma, C.B.How Zambia transformed its emerald industry.InColor, December pp. 18-19.Africa, Zambiaemeralds
DS200812-1286
2008
YamadaYamaguchi, H.,Kudo, Y., Masuzawa, T., Kudo, M., Yamada, Takakuwa, OkanoCombine x-ray photoelectron spectroscopy/ultraviolet photoelectron spectroscopy/field emission spectroscopy for characterization of electron emmision of diamond.Journal of Vacuum Science and Technology B Microelectronics and Nanometer Structures, Vol. 26, 2, pp. 730-734. American Vacuum SocietyTechnologyDiamond emission
DS200812-1288
2008
Yamada, A.Yamamoto, J., Ando, J-i., Kagi, H., Inoue, T., Yamada, A., Yamazaki, D., Irifune, T.In situ strength measurements on natural upper mantle minerals.Physics and Chemistry of Minerals, Vol. 35, pp. 249-257.MantleRheology, geocbarometry
DS201903-0513
2018
Yamada, A.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
Yamada, A.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.
DS1984-0783
1984
Yamada, H.Yamada, H., Takahashi, E.Subsolidus Phase Relations between Coexisting Garnet and Two Pyroxenes at 50 to 100 Kilobar in the System Cao Mgo Al2ossio2.Proceedings of Third International Kimberlite Conference, Vol. 2, PP. 247-255.GlobalGarnet, Composition, Analyses
DS200412-0962
2004
Yamada, H.Katusra, T., Yamada, H., Nishikawa, O., Maoshuang, K., et al.Olivine wadsleyite transition in the system MgFe 2SiO4.Journal of Geophysical Research, Vol. 109, B2, 10.1029/2003 JB002438TechnologyMineral chemistry
DS200812-1287
2008
Yamada, T.Yamaguchi, H., Salto, I., Kudi, Y., Masuzawa, T., Yamada, T., Kudo, M., Takakuma, Y., Okano, K.Electron emission mechanism of hydrogeneated natural type IIb diamond (111).Diamond and Related Materials, Vol. 17, 2, pp. 162-166.TechnologyType II diamonds
DS1993-0792
1993
Yamaguch, A.Kawarada, H., Yamaguch, A.Excitonic recomnbination radiation as characterization of diamonds usingcathodluminescenceDiamond Relat, Vol. 2, No. 2-4, March 31, pp. 100-105GlobalDiamond morphology, Cathodluminescence
DS200412-0843
2004
Yamaguchi, A.Hokada, T., Misawa, K., Yokoyama, K., Shiraishi, K., Yamaguchi, A.SHRIMP and electron microprobe chronology of UHT metamorphism in the Napier Complex, East Antarctica implications for zircon groContributions to Mineralogy and Petrology, Vol. 147, 1, pp. 1-20.AntarcticaGeochronology
DS200812-1286
2008
Yamaguchi, H.Yamaguchi, H.,Kudo, Y., Masuzawa, T., Kudo, M., Yamada, Takakuwa, OkanoCombine x-ray photoelectron spectroscopy/ultraviolet photoelectron spectroscopy/field emission spectroscopy for characterization of electron emmision of diamond.Journal of Vacuum Science and Technology B Microelectronics and Nanometer Structures, Vol. 26, 2, pp. 730-734. American Vacuum SocietyTechnologyDiamond emission
DS200812-1287
2008
Yamaguchi, H.Yamaguchi, H., Salto, I., Kudi, Y., Masuzawa, T., Yamada, T., Kudo, M., Takakuma, Y., Okano, K.Electron emission mechanism of hydrogeneated natural type IIb diamond (111).Diamond and Related Materials, Vol. 17, 2, pp. 162-166.TechnologyType II diamonds
DS201810-2326
2018
Yamaguchi, R.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
Yamaguchi, R.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.
DS1981-0434
1981
Yamaguchi, S.Yamaguchi, S.The Use of Active Carbon for the Synthesis of DiamondZeitschr. Fur Physik. Chemie (leipzig), Vol. 262, No. 4, PP. 131-145.GlobalDiamond Sythesis
DS201703-0407
2017
Yamaguchi, T.Iizuka, T., Yamaguchi, T., Itano, K., Hibiya, Y., Suzuki, K.What Hf isotopes in zircon tell us about crust mantle evolution.Lithos, Vol. 274-275, pp. 304-327.MantleGeochronology

Abstract: The 176Lu-176Hf radioactive decay system has been widely used to study planetary crust-mantle differentiation. Of considerable utility in this regard is zircon, a resistant mineral that can be precisely dated by the U-Pb chronometer and record its initial Hf isotope composition due to having low Lu/Hf. Here we review zircon U-Pb age and Hf isotopic data mainly obtained over the last two decades and discuss their contributions to our current understanding of crust-mantle evolution, with emphasis on the Lu-Hf isotope composition of the bulk silicate Earth (BSE), early differentiation of the silicate Earth, and the evolution of the continental crust over geologic history. Meteorite zircon encapsulates the most primitive Hf isotope composition of our solar system, which was used to identify chondritic meteorites best representative of the BSE (176Hf/177Hf = 0.282793 ± 0.000011; 176Lu/177Hf = 0.0338 ± 0.0001). Hadean-Eoarchean detrital zircons yield highly unradiogenic Hf isotope compositions relative to the BSE, providing evidence for the development of a geochemically enriched silicate reservoir as early as 4.5 Ga. By combining the Hf and O isotope systematics, we propose that the early enriched silicate reservoir has resided at depth within the Earth rather than near the surface and may represent a fractionated residuum of a magma ocean underlying the proto-crust, like urKREEP beneath the anorthositic crust on the Moon. Detrital zircons from world major rivers potentially provide the most robust Hf isotope record of the preserved granitoid crust on a continental scale, whereas mafic rocks with various emplacement ages offer an opportunity to trace the Hf isotope evolution of juvenile continental crust (from ?Hf[4.5 Ga] = 0 to ?Hf[present] = + 13). The river zircon data as compared to the juvenile crust composition highlight that the supercontinent cycle has controlled the evolution of the continental crust by regulating the rates of crustal generation and intra-crustal reworking processes and the preservation potential of granitoid crust. We use the data to explore the timing of generation of the preserved continental crust. Taking into account the crustal residence times of continental crust recycled back into the mantle, we further propose a model of net continental growth that stable continental crust was firstly established in the Paleo- and Mesoarchean and significantly grew in the Paleoproterozoic.
DS200412-1736
2004
Yamaguchi, Y.Satoh, H., Yamaguchi, Y., Makino, K.Ti substitution mechanism in plutonic oxy-kaersutite from the Larvik alkaline complex, Oslo Rift, Norway.Mineralogical Magazine, Vol. 68, 4, Aug. 1, pp. 687-697.Europe, NorwayAlkaline rocks, mineralogy
DS200512-0937
2004
Yamaguchi, Y.Satoh, H., Yamaguchi, Y., Makino, K.Ti substitution mechanism in plutonic oxy-kaesutite from the Larvik alkaline complex, Oslo Rift, Norway.Mineralogical Magazine, Vol. 68, 4, Aug. 1,pp. 687-697.Europe, NorwayPetrology - alkaline
DS200512-1211
2005
Yamaguchi, Y.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
DS201312-0988
2013
Yamaguchi, Y.Yajima, T., Yamaguchi, Y.Geological mapping of the Francistown area in northeastern Botswana by surface temperature and spectral emissivity information derived from advanced spaceborn thermal emission and reflection radiometer (ASTER) thermal infrared data.Ore Geology Reviews, Vol. 53, pp. 134-144.Africa, BotswanaGeothermometry - Aster
DS201905-1037
2019
Yamaguschi, R.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.
DS1992-1712
1992
Yamaji, A.Yamaji, A.Periodic hotspot distribution and small scale convection in the uppermantleEarth and Planetary Science Letters, Vol. 109, No. 1/2, March pp. 107-116MantleMantle convection, Hotspots
DS2002-1179
2002
Yamakata, M.Okada, T., Utsumi, W., Kaneko, H., Yamakata, M., Shimomura, O.In situ observations of the decomposition of brucite diamond conversion in aqueous fluid at high pressure and temperature.Physics and Chemistry of Minerals, Vol. 29, 7, pp. 439-45.GlobalDiamond - UHP, Mineral exploration potential
DS2002-1756
2002
Yamakazi, D.Yamakazi, D., Karoto, S.Fabric development in ( Mg Fe O during large strain, shear deformation: implications for seismic anisotropy in Earth's lower mantle.Physics of the Earth and Planetary Interiors, Vol. 131, 3-4, pp. 251-67.MantleGeophysics - seismics
DS200412-0043
2003
Yamamoto, E.Antonini, P., Comin-Chiaramonti, P., Gomes, C.B., Censi, P., Riffel, B.F., Yamamoto, E.The Early Proterozoic carbonatite complex of Angico dos Dias, Bahia State, Brazil: geochemical and Sr Nd isotopic evidence for aMineralogical Magazine, Vol. 67, 5, pp. 1039-57.South America, BrazilGeochronology, carbonatites
DS2002-1584
2002
Yamamoto, H.Terabayashi, M., Ota, T., Yamamoto, H., Kaneko, Y.Contact metamorphism of the Daulet Suite by solid state emplacement of the Kokchetav UHP HP metamorphic slab.International Geology Review, Vol. 44, 9, pp. 819-30.RussiaUHP
DS201212-0800
2012
Yamamoto, H.Yamamoto, H., Terabayashi, M., Okura, H., Matsui, T., Kanedo, Y.Northward extrusion of the ultrahigh-pressure units in the southern Dabie metamorphic belt, east-central China.Island Arc, in press availableChinaUHP
DS2001-1275
2001
Yamamoto, J.Yamamoto, J., Watanabe, M., Nozaki, SanoHelium and carbon isotopes in fluorites: implications for mantle carbon contribution ancient subduction zoneJournal of Volc. Geotherm. Res., Vol. 107, No. 1-3, pp. 19-26.JapanCarbon - not specific to diamonds
DS2002-1757
2002
Yamamoto, J.Yamamoto, J., Kagi, H., Kaneoka, Lai, Prikhodko,AraiFossil pressures of fluid inclusions in mantle xenoliths exhibiting rheology of mantle minerals...Earth and Planetary Science Letters, Vol.198,3-4,pp.511-19., Vol.198,3-4,pp.511-19.MantleSpectroscopy, Geobarometry - mantle minerals
DS2002-1758
2002
Yamamoto, J.Yamamoto, J., Kagi, H., Kaneoka, Lai, Prikhodko,AraiFossil pressures of fluid inclusions in mantle xenoliths exhibiting rheology of mantle minerals...Earth and Planetary Science Letters, Vol.198,3-4,pp.511-19., Vol.198,3-4,pp.511-19.MantleSpectroscopy, Geobarometry - mantle minerals
DS2003-0697
2003
Yamamoto, J.Kawakami, Y., Yamamoto, J., Kagi, H.Micro raman densimeter for CO2 inclusions in mantle derived mineralsApplied Spectroscopy, Vol. 57, 11, pp. 1333-1339.MantleMineralogy - technology
DS200412-0965
2003
Yamamoto, J.Kawakami, Y., Yamamoto, J., Kagi, H.Micro raman densimeter for CO2 inclusions in mantle derived minerals.Applied Spectroscopy, Vol. 57, 11, pp. 1333-1339.MantleMineralogy - technology
DS200412-1436
2004
Yamamoto, J.Nishio, Y., Nakai, S., Yamamoto, J., Sumino, H., Matsumoto, T., Prikhodko, V.S., Arai, S.Lithium isotopic systematics of the mantle derived ultramafic xenoliths: implications for EMI origin.Earth and Planetary Science Letters, Vol. 217, 3, Jan. 15, pp. 245-261.MantleGeochronology
DS200412-2165
2004
Yamamoto, J.Yamamoto, J., Kaneoka, I., Nakai, S., Kagi, H., Prikhodko, V.S., Arai, S.Evidence for subduction related components in the subcontinental mantle from low 3He/4He and 40Ar/36Ar ratio in mantle xenolithsChemical Geology, Vol. 207, 3-4, July 16, pp. 237-259.RussiaGeochemistry - noble gases, subduction, lherzolite
DS200712-0514
2006
Yamamoto, J.Kawakami, Y., Yamamoto, J., Kagi, H.Micro-raman densimeter for CO2 inclusions in mantle derived minerals.Applied Spectroscopy, Vol. 57, 11, pp. 1333-1339.TechnologyMineral inclusions
DS200712-1197
2007
Yamamoto, J.Yamamoto, J., Kagi, H., Kawakami, Y., Hirano, N., Nakamura, M.Paleo-Moho depth determined from the pressure of CO2 fluid inclusions: Raman spectroscopic barometry of mantle crust derived rocks.Earth and Planetary Science Letters, Vol. 253, 3-4, pp. 369-377.MantleGeothermometry
DS200812-1288
2008
Yamamoto, J.Yamamoto, J., Ando, J-i., Kagi, H., Inoue, T., Yamada, A., Yamazaki, D., Irifune, T.In situ strength measurements on natural upper mantle minerals.Physics and Chemistry of Minerals, Vol. 35, pp. 249-257.MantleRheology, geocbarometry
DS200912-0771
2009
Yamamoto, J.Toyama, C., Muramatsu, Y., Kojitani, H., Yamamoto, J., Nakai, S., Kaneoka, I.Geochemical studies of kimberlites and their constituent minerals from Chin a and South Africa.Goldschmidt Conference 2009, p. A1343 Abstract.ChinaDeposit - Shandong, Liaoning
DS200912-0831
2009
Yamamoto, J.Yamamoto, J.,Nakai, S., Nishimura, K., Kaneoka, I., Sato, K., Okumura, T., Prikhodko,V.S., Arai, S.Intergranular trace elements in mantle xenoliths from Russian Far East: example for mantle metasomatism by hydrous melt.Island Arc, Vol. 18, 1, pp. 225-241.RussiaMetasomatism
DS201012-0878
2010
Yamamoto, J.Yoshikawa, M., Kawamoto, T., Shibata, T., Yamamoto, J.Geochemical and Sr Nd isotopic characteristics and pressure temperature estimates of mantle xenoliths from French Massif Central: metasomatism and carbonatites..Geological Society of London Special Publication, No. 337, pp. 153-175.Europe, FranceCarbonatite
DS201112-1130
2011
Yamamoto, J.Yamamoto, J., Kurz, M.D., Ishibashi, H., Curtice, J.Noble gas isotopic composition of mantle xenoliths in a kimberlite.Goldschmidt Conference 2011, abstract p.2201.Russia, SiberiaKimberlite magma
DS201312-0922
2013
Yamamoto, J.Toyama, C., Muramatsu, Y., Sumino, H., Yamamoto, J., Kaneoka, I.Halogen ratios in kimberlites and their xenoliths related to the origin.Goldschmidt 2013, 1p. AbstractRussia, Africa, South AfricaKimberlite genesis
DS201805-0968
2018
Yamamoto, J.Ono, K., Harada, Y., Yoneda, A., Yamamoto, J., Yoshiasa, A., Sugiyama, K., Arima, H., Watanabe, T.Determination of elastic constants of single crystal chromian spinel by resonant ultrasound spectroscopy and implications for fluid inclusion geobarometry.Physics and Chemistry of Minerals, Vol. 45, 3, pp. 237-247.Technologyxenolths

Abstract: We determined elastic constants of a single-crystal chromian spinel at temperatures from ?15 to 45 °C through the Rectangular Parallelepiped Resonance method. The sample is a natural chromian spinel, which was separated from a mantle xenolith. Elastic constants at an ambient temperature (T = 24.0 °C) are C 11 = 264.8(1.7) GPa, C 12 = 154.5(1.8) GPa and C 44 = 142.6(0.3) GPa. All the elastic constants decrease linearly with increasing temperature. The temperature derivatives are dC 11/dT = ?0.049(2) GPa/°K, dC 12/dT = ?0.019(1) GPa/°K and dC 44/dT = ?0.020(1) GPa/°K. As an implication of the elastic constants, we applied them to the correction of a fluid inclusion geobarometry, which utilizes residual pressure of fluid inclusion as a depth scale. Before entrainment by a magma, the fluid inclusions must have the identical fluid density in constituent minerals of a xenolith. It has been, however, pointed out that fluid density of fluid inclusions significantly varies with host mineral species. The present study elucidates that elastic constants and thermal expansion coefficients cannot explain the difference in fluid density among mineral species. The density difference would reflect the difference in the degree of plastic deformation in the minerals.
DS202201-0044
2021
Yamamoto, J.Toyama, C., Sumino, H., Okabe, N., Ishikawa, A., Yamamoto, J., Kaneoka, I., Muramatsu, Y.Halogen heterogeneity in the subcontinental lithospheric mantle revealed by I/Br ratios in kimberlites and their mantle xenoliths from South Africa, Greenland, China, Siberia, Canada and Brazil.American Mineralogist, Vol. 106, pp. 1890-1899.Africa, South Africa, Europe, Greenland, China, Russia, Siberia, Canada, South America, Brazilsubduction, metasomatism

Abstract: To investigate halogen heterogeneity in the subcontinental lithospheric mantle (SCLM), we measured the concentrations of Cl, Br, and I in kimberlites and their mantle xenoliths from South Africa, Greenland, China, Siberia, Canada, and Brazil. The samples can be classified into two groups based on halogen ratios: a high-I/Br group (South Africa, Greenland, Brazil, and Canada) and a low-I/Br group (China and Siberia). The halogen compositions were examined with the indices of crustal contamination using Sr and Nd isotopes and incompatible trace elements. The results indicate that the difference between the two groups was not due to different degrees of crustal contamination but from the contributions of different mantle sources. The low-I/Br group has a similar halogen composition to seawater-influenced materials such as fluids in altered oceanic basalts and eclogites and fluids associated with halite precipitation from seawater. We conclude that the halogens of the high-I/Br group are most likely derived from a SCLM source metasomatized by a fluid derived from subducted serpentinite, whereas those of the low-I/Br group are derived from a SCLM source metasomatized by a fluid derived from seawater-altered oceanic crust. The SCLM beneath Siberia and China could be an important reservoir of subducted, seawater-derived halogens, while such role of SCLM beneath South Africa, Greenland, Canada, and Brazil seems limited.
DS200612-0880
2006
Yamamoto, K.Matsumoto, T., Maruoka, T., Matsuda, J-I., Shimoda, G., Yamamoto, K., Morishita, T., Arai, S.Isotopic compositions of noble gas and carbon in the Archean carbonatites from the Sillinjarvi mine, central Finland.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 21, abstract only.Europe, FinlandCarbonatite, geochronology
DS201511-1854
2015
Yamamoto, M.Kitawaki, H., Hisanaga, M., Yamamoto, M.Type 1b yellow to brownish yellow CVD synthetic diamonds seen at CGL.Journal of Gemmology, Vol. 34, 7, pp. 594-605.TechnologySynthetics

Abstract: In mid-2012, one of the international diamond grading laboratories in Antwerp reported undisclosed CVD synthetic diamonds, causing a stir in the diamond industry (Even-Zohar, 2012). Since then, reports of undisclosed CVD synthetics have also emerged from gem testing laboratories in India and China (D’ Haenens-Johanson et al., 2013; Song et al., 2014). Central Gem Laboratory (CGL) also reported on undisclosed over 1 ct size CVD synthetic diamonds (Kitawaki et al., 2013). Gem quality CVD products have been improved in their size and quality year after year, and a variety of colours have appeared. Most of the CVD synthetic diamonds reported previously are type II, however, recently some yellow CVD synthetic diamonds containing isolated substitutional nitrogen have been supplied to the gem market (Moe et al., 2014; Hainschwang, 2014). This report describes the gemmological features of fifteen yellow to brownish yellow type Ib CVD synthetic diamonds submitted to CGL without disclosure.
DS201901-0044
2018
Yamamoto, M.Kitawaki, H., Emori, K., Hisanaga, M., Yamamoto, M., Okano, M.LPHT treated pink CVD synthetic diamond.Gems & Gemology, Sixth International Gemological Symposium Vol. 54, 3, 1p. Abstract p. 267.Globalsynthetics

Abstract: Pink diamond is extremely popular among fancy-color diamonds, which has prompted numerous attempts to produce pink diamond artificially. Pink CVD synthetic diamonds appeared on the gem market around 2010. Their color was produced by a multistep process combining post-growth HPHT treatment to remove the brown hue and subsequent electron irradiation, followed by low-temperature annealing. Pink CVD synthetic diamonds treated only with low pressure and high temperature (LPHT), without additional post-growth irradiation, have also been reported but are rarely seen on the market. Recently, a loose pink stone (figure 1) was submitted to the Central Gem Laboratory in Tokyo for grading purposes. Our examination revealed that this 0.192 ct brilliant-cut marquise was a CVD synthetic diamond that had been LPHT treated. Visually, this diamond could not be distinguished from natural diamonds with similar color. However, three characteristics of CVD origin were detected: 1. C-H related absorption peaks between 3200 and 2800 cm-1, located with infrared spectroscopy 2. A luminescence peak at 737 nm, detected with photoluminescence (PL) spectroscopy 3. A trace of lamellar pattern seen in the DiamondView However, irradiation-related peaks such as at 1450 cm-1 (H1a), 741.1 nm (GR1), 594.3 nm, or 393.5 nm (ND1) that are seen in the pink CVD diamonds treated with common multi-step processes were not detected. The presence of four peaks at 3123, 2901, 2870, and 2812 cm-1 between 3200 and 2800 cm-1 suggests this stone was LPHT treated; the following observations indicate that it was not HPHT treated: 1) The 3123 cm-1 peak presumably derived from NVH0 disappears after a normal HPHT treatment. 2) The 2901, 2870, and 2812 cm-1 peaks are known to shift toward higher wavenumbers as the annealing temperature rises. Our own HPHT treatment experiments on CVDgrown diamonds proved that the 2902 and 2871 cm-1 peaks detected after 1600°C annealing shifted to 2907 and 2873 cm-1 after 2300°C annealing. The peak shift of 2901, 2870, and 2812 cm-1 is also related to the pressure during the annealing, as these peaks shifted to 2902, 2871, and 2819 cm-1 at the higher pressure of 7 GPa compared to 2900, 2868, and 2813 cm-1 at the ambient pressure under the same annealing temperature of 1600°C. 3) Absorption peaks at 7917 and 7804 cm-1 in the infrared region and at 667 and 684 nm in the visible range were also detected, which coincide with the features seen in LPHTtreated stones. From the combination of the intensity ratios of optical centers such as H3 and NV centers that were detected with PL measurement, this sample is presumed to have been treated with LPHT annealing at about 1500- 1700°C as a post-growth process. In recent years, CVD synthetic diamonds have been produced in a wider range of colors due to progress in the crystal growth techniques and post-growth treatments. Although HPHT treatment has been employed mainly to improve the color in a diamond, LPHT annealing may become widespread as the technique is further developed. Gemologists need to have deep knowledge about the optical defects in such LPHT-treated specimens.
DS200912-0664
2009
Yamamoto, S.Santosh, M., Maruyana, S., Yamamoto,S.The making and breaking od supercontinents: some speculations based on superplumes, super downwelling and the role of tectosphere.Gondwana Research, Vol. 15, 3-4, pp. 324-341.MantlePlume, hotspots
DS201012-0643
2010
Yamamoto, S.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
DS201012-0659
2010
Yamamoto, S.Santosh, M., Maruyama, S., Komiya, T., Yamamoto, S.Orogens in the evolving Earth: from surface continents to 'lost continents'.The evolving continents: understanding processes of continental growth, Geological Society of London, Vol. 338, pp. 77-106.MantleGeodynamics
DS201312-0464
2013
Yamamoto, S.Kawai, K., Yamamoto, S.,Tsuchiya, T., Maruyama, S.The second continent: existence of granitic continental materials around the bottom of the mantle transition zone.Geoscience Frontiers, Vol. 4, 1, pp. 1-6.MantleGranites
DS201612-2278
2016
Yamamoto, S.Azuma, S., Yamamoto, S., Ichikawa, H., Maruyama, S.Why primordial continents were recycled to the deep: role of subduction erosion.Geoscience Frontiers, in press availableMantleSubduction

Abstract: Geological observations indicate that there are only a few rocks of Archean Earth and no Hadean rocks on the surface of the present-day Earth. From these facts, many scientists believe that the primordial continents never existed during Hadean Earth, and the continental volume has kept increasing. On the other hand, recent studies reported the importance of the primordial continents on the origin of life, implying their existence. In this paper, we discussed the possible process that could explain the loss of the primordial continents with the assumption that they existed in the Hadean. Although depending on the timing of the initiation of plate tectonics and its convection style, subduction erosion, which is observed on the present-day Earth, might have carried the primordial continents into the deep mantle.
DS201707-1322
2017
Yamamoto, T.Fei, H., Yamazaki, D., Sakurai, M., Miyajima, N., Ohfuji, H., Katsura, T., Yamamoto, T.A nearly water-saturated mantle transition zone inferred from mineral viscosity. Wadsleyite, ringwooditeScience Advances, Vol. 3, 6, 7p.Mantlewater

Abstract: An open question for solid-earth scientists is the amount of water in Earth’s interior. The uppermost mantle and lower mantle contain little water because their dominant minerals, olivine and bridgmanite, have limited water storage capacity. In contrast, the mantle transition zone (MTZ) at a depth of 410 to 660 km is considered to be a potential water reservoir because its dominant minerals, wadsleyite and ringwoodite, can contain large amounts of water [up to 3 weight % (wt %)]. However, the actual amount of water in the MTZ is unknown. Given that water incorporated into mantle minerals can lower their viscosity, we evaluate the water content of the MTZ by measuring dislocation mobility, a property that is inversely proportional to viscosity, as a function of temperature and water content in ringwoodite and bridgmanite. We find that dislocation mobility in bridgmanite is faster by two orders of magnitude than in anhydrous ringwoodite but 1.5 orders of magnitude slower than in water-saturated ringwoodite. To fit the observed mantle viscosity profiles, ringwoodite in the MTZ should contain 1 to 2 wt % water. The MTZ should thus be nearly water-saturated globally.
DS201911-2534
2019
Yamamoto, T.Ishi, T., Huang, R., Myhill, R., Fei, H., Koemets, I., Liu, Z., Maeda, F., Yuan, L., Wang, L., Druzhbin, D., Yamamoto, T., Bhat, S., Farla, R., Kawazoe, T., Tsujino, N., Kulik, E., Higo, Y., Tange, H., Katsura, T.Sharp 660 km discontinuity controlled by extremely narrow binary post-spinel transition.Nature Geosciences, Vol. 12, pp. 869-872.Mantlediscontinuity

Abstract: The Earth’s mantle is characterized by a sharp seismic discontinuity at a depth of 660?km that can provide insights into deep mantle processes. The discontinuity occurs over only 2?km—or a pressure difference of 0.1?GPa—and is thought to result from the post-spinel transition, that is, the decomposition of the mineral ringwoodite to bridgmanite plus ferropericlase. Existing high-pressure, high-temperature experiments have lacked the pressure control required to test whether such sharpness is the result of isochemical phase relations or chemically distinct upper and lower mantle domains. Here, we obtain the isothermal pressure interval of the Mg-Fe binary post-spinel transition by applying advanced multi-anvil techniques with in situ X-ray diffraction with the help of Mg-Fe partition experiments. It is demonstrated that the interval at mantle compositions and temperatures is only 0.01?GPa, corresponding to 250?m. This interval is indistinguishable from zero at seismic frequencies. These results can explain the discontinuity sharpness and provide new support for whole-mantle convection in a chemically homogeneous mantle. The present work suggests that distribution of adiabatic vertical flows between the upper and lower mantles can be mapped on the basis of discontinuity sharpness.
DS200712-1090
2007
Yamamotto, J.Tooyama, C., Muramatsu, Y., Yamamotto, J., Kaneoka, I.Determin ation of 33 elements in kimberlites from South Africa and Chin a by ICP-MS.Plates, Plumes, and Paradigms, 1p. abstract p. A1030.Africa, South Africa, ChinaShandon, Liaoning
DS200412-1461
2004
Yamanaka, T.Ohtaka, O., Shimono, M., Ohnisi, N., Fukui, H., Takebe, H., Arima, H., Yamanaka, T.,Kikegawa, T., Kume, S.HIP production of a diamond/ SiC composite and application to high pressure anvils.Physics of the Earth and Planetary Interiors, Vol. 143-144, pp. 587-591.TechnologyUHP
DS1995-2095
1995
Yama-Nkounga, A.Yama-Nkounga, A.Some aspects of privatization in the African mining sector and relatedindustriesMinerals Industry International, November pp. 16-17Africa, South AfricaEconomics, Mining
DS1993-0015
1993
Yamaoka, S.Akaishi, M., Kanda, H., Yamaoka, S.Phosphorous: an elemental catalyst for diamond synthesis and growthScience, Vol. 259, No. 5101, March 12, pp. 1592-1593GlobalDiamond synthesis
DS1993-0041
1993
Yamaoka, S.Arima, M., Nakayama, K., Akaishi, M., Yamaoka, S., Kanda, H.Crystallization of diamond from a silicate melt of kimberlite composition in high temperature and high pressure experiments.Geology, Vol. 21, No. 11, November pp. 968-970.GlobalDiamond genesis, Experimental petrology
DS200712-1063
2007
Yamasaki, S.Takuda, N., Saito, T., Umezawa, H., Okushi, H., Yamasaki, S.The role of boron atoms in heavily boron doped semiconducting homoepitaxial diamond growth - study of surface morphology.Diamond and Related Materials, Vol. 16, 2, Feb., pp. 409-411.TechnologyDiamond morphology
DS200712-1086
2007
Yamasaki, S.Tokuda, N., Saito, T., Umezawa, H., Okushi, H., Yamasaki, S.The role of boron atoms in heavily boron-doped semiconducting homoepitaxial diamond growth. Study of surface morphology.Diamond and Related Materials, Vol. 16, 2, pp. 409-411. Ingenta 1070685096TechnologyDiamond morphology
DS1992-1713
1992
Yamashita, H.Yamashita, H., Arima, M.Melting experiment of group II kimberlites up to 10 GPa: petrogenesis Of kimberlite magmaProceedings of the 29th International Geological Congress. Held Japan August 1992, Vol. 2, abstract p. 538GlobalExperimental petrology, Kimberlites
DS1994-0062
1994
Yamashita, H.Arima, M., Yamashita, H., Ohtani, E.Melting experiments of kimberlite up to 8GPa and its bearing onMetasomatismGeological Association of Canada (GAC) Abstract Volume, Vol. 19, p.GlobalPetrology - experimenta, Metasomatism
DS1995-2096
1995
Yamashita, H.Yamashita, H., Arima, M., Ohtani, E.high pressure melting experiments on group II kimberlite up to 8 GPa:implications MetasomatismProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 669-691.GlobalPetrology -experimental, Group II kimberlite
DS1998-1609
1998
Yamashita, H.Yamashita, H., Arima, M., Ohtani, E.Melting experiments of kimberlite compositions up to 9 GPa: determination of melt compositions using aggregate7th International Kimberlite Conference Abstract, pp. 977-9.GlobalExperimental petrology, Mineral chemistry
DS1994-1960
1994
Yamashita, K.Yanagi, T., Yamashita, K.Genesis of continental crust under arc conditionsLithos, Vol. 33, pp. 209-233MantleVolcanics, Subduction - arcs
DS200912-0324
2009
Yamato, P.Husson, L., Brun, J-P., Yamato, P., Faccenna, C.Episodic slab rollback fosters exhumation of HP-UHP rocks.Geophysical Journal International, Vol. 179, 3, pp. 1291-1300.MantleUHP
DS201312-0112
2014
Yamato, P.Burov, E., Francois, T., Yamato, P., Wolf, S.Mechanisms of continental subduction and exhumation of HP and UHP rocks.Gondwana Research, Vol. 25, pp. 464-493.MantleSubduction
DS201412-0085
2014
Yamato, P.Burov, E., Francois, T., Yamato, P., Wolf, S.Mechanisms of continental subduction and exhumation of HP and UHP rocks.Gondwana Research, Vol. 25, pp. 464-493.MantleSubduction, Eclogites
DS201702-0255
2016
Yamato, P.Yamato, P., Brun, J.P.Metamorphic record of catastrophic pressure drop in subduction zones.Nature Geoscience, Vol. 10, pp. 46-50.MantleSubduction

Abstract: When deeply buried in subduction zones, rocks undergo mineral transformations that record the increase of pressure and temperature. The fact that high-pressure metamorphic parageneses are found at the Earth’s surface proves that rock burial is followed by exhumation. Here we use analysis of available data sets from high-pressure metamorphic rocks worldwide to show that the peak pressure is proportional to the subsequent decompression occurring during the initial stage of retrogression. We propose, using a simple mechanical analysis, that this linear relationship can be explained by the transition from burial-related compression to extension at the onset of exhumation. This major switch in orientation and magnitude of principal tectonic stresses leads to a catastrophic pressure drop prior to actual rock ascent. Therefore, peak pressures are not necessarily, as commonly believed, directly dependent on the maximum burial depth, but can also reflect a change of tectonic regime. Our results, which are in agreement with natural data, have significant implications for rock rheology, subduction zone seismicity, and the magnitudes of tectonic pressures sustained by rocks. Current views of subduction dynamics could be reconsidered in that perspective.
DS201909-2108
2019
Yamato, P.Yamato, P., Duretz, T., Angiboust, S.Brittle/ductile deformation of eclogites: insights from numerical models.Geochemistry, Geophysics, Geosystems, Vol. 20, 7, pp. 3116-3133.mantleeclogites

Abstract: How rocks deform at depth during lithospheric convergence and what are the magnitudes of stresses they experience during burial/exhumation processes constitute fundamental questions for refining our vision of short?term (i.e., seismicity) and long?term tectonic processes in the Earth's lithosphere. Field evidence showing the coexistence of both brittle and ductile deformation at high pressure?low temperature (HP?LT) conditions particularly fuels this questioning. We here present 2D numerical models of eclogitic rock deformation by simple shear performed at centimeter scale. To approximate the eclogite paragenesis, we considered the deformed medium as composed of two mineral phases: omphacite and garnet. We run a series of models at 2.0 GPa and 550 °C for different background strain rates (from 10?14 s?1 to 10?8 s?1) and for different garnet proportions (from 0% to 55%). Results show that whole rock fracturing can occur under HP?LT conditions for strain rates larger than ~10?10 s?1. This suggests that observation of brittle features in eclogites does not necessarily mean that they underwent extreme strain rate. Care should therefore be taken when linking failure of eclogitic rocks to seismic deformation. We also explore the ranges of parameters where garnet and omphacite are deforming with a different deformation style (i.e., frictional vs viscous) and discuss our results in the light of naturally deformed eclogitic samples. This study illustrates that effective stresses sustained by rocks can be high at these P?T conditions. They reach up to ~1 GPa for an entirely fractured eclogite and up to ~500 MPa for rocks that contain fractured garnet.
DS2002-1319
2002
Yamauchi, J.Reddy, B.J., Yamauchi, J., Reddy, Ravikumar, ChandraseskharOptical and EPR spectra of Ti 3 in lamprophyllite from Kola Peninsula, RussiaNeues Jahrbuch fur Mineralogie - Monatshefte, No.3, March,ppp.138-40.Russia, Kola PeninsulaMineralogy - titanium
DS2002-1175
2002
YamazakiO'Hara, Y., Stern, Ishii, Yurimoto, YamazakiPeridotites from the Mariana Trough: first look at the mantle beneath an active back-arc basin.Contribution to Mineralogy and Petrology, Vol.143,1,pp.1-18., Vol.143,1,pp.1-18.Mariana TroughPeridotites
DS2002-1176
2002
YamazakiO'Hara, Y., Stern, Ishii, Yurimoto, YamazakiPeridotites from the Mariana Trough: first look at the mantle beneath an active back-arc basin.Contribution to Mineralogy and Petrology, Vol.143,1,pp.1-18., Vol.143,1,pp.1-18.Mariana TroughPeridotites
DS2001-1276
2001
Yamazaki, D.Yamazaki, D., Karato, S.I.Some mineral physics constraints on the rheology and geothermal structures of Earth's lower mantle.American Mineralogist, Vol. 86, No. 4, April pp. 385-391.MantleGeothermometry
DS200512-1212
2005
Yamazaki, D.Yamazaki, D., Inoue, T., Okamoto, M., Irifune, T.Grain growth kinetics of ring woodite and its implication for rheology of the subducting slab.Earth and Planetary Science Letters, Advanced in press,MantleSubduction, mantle transition zone
DS200712-1207
2007
Yamazaki, D.Yoshino, T., Yamazaki, D.Grain growth kinetics of CalrO3 perovskite and post-perovskite, with implications for rheology of D' layer.Earth and Planetary Science Letters, Vol. 255, 3-4, March 30, pp. 485-493.MantleD layer
DS200812-1288
2008
Yamazaki, D.Yamamoto, J., Ando, J-i., Kagi, H., Inoue, T., Yamada, A., Yamazaki, D., Irifune, T.In situ strength measurements on natural upper mantle minerals.Physics and Chemistry of Minerals, Vol. 35, pp. 249-257.MantleRheology, geocbarometry
DS201412-0812
2014
Yamazaki, D.Shimojuku, A., Boujibar, A., Yamazaki, D.Growth of ring woodite reaction rims from MgSiO3 perovskite and periclase at 22.5 Gpa and 1,800 C.Physics and Chemistry of Minerals, Vol. 41, 7, pp. 555-567.TechnologyPerovskite
DS201611-2145
2016
Yamazaki, D.Tsujino, N., Yamazaki, D., Takahashi, E.Mantle dynamics inferred from the crystallographic preferred orientation of bridgmanite.Nature, Oct. 20, 15p.MantlePerovskite

Abstract: Seismic shear wave anisotropy1, 2, 3, 4, 5, 6 is observed in Earth’s uppermost lower mantle around several subducted slabs. The anisotropy caused by the deformation-induced crystallographic preferred orientation (CPO) of bridgmanite (perovskite-structured (Mg,Fe)SiO3) is the most plausible explanation for these seismic observations. However, the rheological properties of bridgmanite are largely unknown. Uniaxial deformation experiments7, 8, 9 have been carried out to determine the deformation texture of bridgmanite, but the dominant slip system (the slip direction and plane) has not been determined. Here we report the CPO pattern and dominant slip system of bridgmanite under conditions that correspond to the uppermost lower mantle (25 gigapascals and 1,873 kelvin) obtained through simple shear deformation experiments using the Kawai-type deformation-DIA apparatus10. The fabrics obtained are characterized by [100] perpendicular to the shear plane and [001] parallel to the shear direction, implying that the dominant slip system of bridgmanite is [001](100). The observed seismic shear- wave anisotropies near several subducted slabs1, 2, 3, 4 (Tonga-Kermadec, Kurile, Peru and Java) can be explained in terms of the CPO of bridgmanite as induced by mantle flow parallel to the direction of subduction.
DS201707-1322
2017
Yamazaki, D.Fei, H., Yamazaki, D., Sakurai, M., Miyajima, N., Ohfuji, H., Katsura, T., Yamamoto, T.A nearly water-saturated mantle transition zone inferred from mineral viscosity. Wadsleyite, ringwooditeScience Advances, Vol. 3, 6, 7p.Mantlewater

Abstract: An open question for solid-earth scientists is the amount of water in Earth’s interior. The uppermost mantle and lower mantle contain little water because their dominant minerals, olivine and bridgmanite, have limited water storage capacity. In contrast, the mantle transition zone (MTZ) at a depth of 410 to 660 km is considered to be a potential water reservoir because its dominant minerals, wadsleyite and ringwoodite, can contain large amounts of water [up to 3 weight % (wt %)]. However, the actual amount of water in the MTZ is unknown. Given that water incorporated into mantle minerals can lower their viscosity, we evaluate the water content of the MTZ by measuring dislocation mobility, a property that is inversely proportional to viscosity, as a function of temperature and water content in ringwoodite and bridgmanite. We find that dislocation mobility in bridgmanite is faster by two orders of magnitude than in anhydrous ringwoodite but 1.5 orders of magnitude slower than in water-saturated ringwoodite. To fit the observed mantle viscosity profiles, ringwoodite in the MTZ should contain 1 to 2 wt % water. The MTZ should thus be nearly water-saturated globally.
DS202202-0208
2022
Yamazaki, D.Murakami, M., Goncharov, A.F., Miyajima, N., Yamazaki, D., Holtgrewe, N.Radiative thermal conductivity of single-crystal bridgmanite at the core-mantle boundary with implications for thermal evolution of the Earth.Earth and planetary Science Letters, Vol. 578, 117328, 9p. PdfMantlebridgmanite

Abstract: The Earth has been releasing vast amounts of heat from deep Earth's interior to the surface since its formation, which primarily drives mantle convection and a number of tectonic activities. In this heat transport process the core-mantle boundary where hot molten core is in direct contact with solid-state mantle minerals has played an essential role to transfer thermal energies of the core to the overlying mantle. Although the dominant heat transfer mechanisms at the lowermost mantle is believed to be both conduction and radiation of the primary lowermost mantle mineral, bridgmanite, the radiative thermal conductivity of bridgmanite has so far been poorly constrained. Here we revealed the radiative thermal conductivity of bridgmanite at core-mantle boundary is substantially high approaching to ?5.3±1.2 W/mK based on newly established optical absorption measurement of single-crystal bridgmanite performed in-situ under corresponding deep lower mantle conditions. We found the bulk thermal conductivity at core-mantle boundary becomes ?1.5 times higher than the conventionally assumed value, which supports higher heat flow from core, hence more vigorous mantle convection than expected. Results suggest the mantle is much more efficiently cooled, which would ultimately weaken many tectonic activities driven by the mantle convection more rapidly than expected from conventionally believed thermal conduction behavior.
DS202201-0027
2021
Yamazakid, D.Mukakami, M., Goncharov, A,F., Miyajimac, N., Yamazakid, D., Holtgrewe, N.Radiative thermal conductivity of single-crystal bridgmanite at the core-mantle boundary with implications for thermal evolution of the Earth.Earth and Planetary Science Letters, Vol. 578, 9p. PdfMantlebridgmanite

Abstract: The Earth has been releasing vast amounts of heat from deep Earth's interior to the surface since its formation, which primarily drives mantle convection and a number of tectonic activities. In this heat transport process the core-mantle boundary where hot molten core is in direct contact with solid-state mantle minerals has played an essential role to transfer thermal energies of the core to the overlying mantle. Although the dominant heat transfer mechanisms at the lowermost mantle is believed to be both conduction and radiation of the primary lowermost mantle mineral, bridgmanite, the radiative thermal conductivity of bridgmanite has so far been poorly constrained. Here we revealed the radiative thermal conductivity of bridgmanite at core-mantle boundary is substantially high approaching to ?5.3±1.2 W/mK based on newly established optical absorption measurement of single-crystal bridgmanite performed in-situ under corresponding deep lower mantle conditions. We found the bulk thermal conductivity at core-mantle boundary becomes ?1.5 times higher than the conventionally assumed value, which supports higher heat flow from core, hence more vigorous mantle convection than expected. Results suggest the mantle is much more efficiently cooled, which would ultimately weaken many tectonic activities driven by the mantle convection more rapidly than expected from conventionally believed thermal conduction behavior.
DS201412-0997
2014
Yambissa, M.T.Yambissa, M.T., Bingham, P.A., Forder, S.D.Mantle conditions and geochemical environment as controls of diamond survival and grade variation in kimberlitic diamond deposits: Lunda Province NE Angola.30th. International Conference on Ore Potential of alkaline, kimberlite and carbonatite magmatism. Sept. 29-, http://alkaline2014.comAfrica, AngolaDiamond grade
DS1989-1143
1989
Yambrick, R.A.Nutt, C.J., Yambrick, R.A.Preliminary geologic map showing igneous related breccias in Cambrian and older quartzites. DrumMountains, UtahUnited States Geological Survey (USGS) Open File, No. 89-0099, 1 sheet 1, 12, 000 $ 3.25UtahDrum Mountains, Breccias
DS1990-1204
1990
Yamnova, N.A.Pushcharovsky, D.Yu., Yamnova, N.A., Nadezhina, T.N.Comparative crystal chemistry of new minerals from alkaline rocksInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 334-335RussiaAlkaline rocks, Geochemistry
DS1990-0106
1990
Yamoka, S.Akaishi, M., Kanda, H., Yamoka, S.Synthesis of diamond from graphite-carbonate systems under very high temperature and pressureJournal of Crystal Growth, Vol. 104, pp. 578-581GlobalDiamond synthesis, Experimental mineralogy
DS1990-1605
1990
Yampolskaya, E.G.Yakovleva, T.P., Leskina, L.M., Matyukhin, V.V., Yampolskaya, E.G.Functional state and sickness rate of diamond processing workers. (Russian)Gig Tr Prof. Zabol., (russian), No. 8, pp. 38-42RussiaDiamond processing, Workers
DS2001-0072
2001
YanBai, W. Yang, Robinson, Febg, Zhang, Yan, HuStudy of diamonds from chromitites in the Luobusa ophiolite, TibetActa Geologica Sinica, Vol. 75, No. 3, pp. 409-17.China, TibetChromitites - diamond
DS2001-0073
2001
YanBai, W., Yang, J., Fang, Yan, ZhangExplosion of ultrahigh pressure minerals in the mantleActa Geologica Sinica, Vol. 22, No. 5, pp. 385-90.MantleUHP
DS200612-0071
2006
Yan, B.Bai, W., Ren, Y., Yang, J., Fang, Q., Yan, B.The native iron and wustite assemblage: records of oxygen element from the mantle.Acta Geologica Sinica , Vol. 27, 1, pp. 43-50.MantleMineral chemistry
DS201802-0225
2018
Yan, B.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
DS201312-0539
2013
Yan, C.Liang, Q., Meng, Y., Yan, C., Krasnicki, S., Lai, J., Hemawan, K., Shu,H., Popov, D., Yu,T., Yang, W., Mao, H., Hemley, R.Developments in synthesis, characterization, and application of large high-quality CVD single crystal diamond.Journal of Superhard Materials, Vol. 35, 4, pp. 195-213.TechnologyDiamond synthetics
DS200512-0421
2005
Yan, C-S.Hemley, R.J.,Chun Chen, Y., Yan, C-S.Growing diamond crystals by chemical vapor deposition.Elements, Vol. 1, 2, March pp. 105-108.CVD, HP
DS2002-1792
2002
Yan, D-P.Zhou, M-F., Yan, D-P., Kennedy, A.K., Li, Y., Ding, J.SHRIMP U Pb zircon geochronology and geochemical evidence for Neoproterozoic arc magmatism along marginEarth and Planetary Science Letters, Vol.196, 1-2, Feb.28, pp.51-67.China, SouthYangtze Block - western margin, Geochemistry, uranium, lead isotopes
DS200812-1289
2008
Yan, J.Yan, J., Chen, J-F., Xu, X-S.Geochemistry of Cretaceous mafic rocks from the Lower Yangtze region, eastern China: characteristics and evolution of the lithospheric mantle.Journal of Asian Earth Sciences, Vol. 33, 3-4, July 15, pp. 177-193.ChinaGeochemistry
DS202004-0547
2020
Yan, J.Yan, J., Ballmer, M.D., Tackley, P.J.The evolution and distribution of recycled oceanic crust in the Earth's mantle: insight from geodynamic models.Earth and Planetary Science Letters, Vol. 537, 116171 12p. PdfMantlegeothermometry

Abstract: A better understanding of the Earth's compositional structure is needed to place the geochemical record of surface rocks into the context of Earth accretion and evolution. Cosmochemical constraints imply that lower-mantle rocks may be enriched in silica relative to upper-mantle pyrolite, whereas geophysical observations support whole-mantle convection and mixing. To resolve this discrepancy, it has been suggested that subducted mid-ocean ridge basalt (MORB) segregates from subducted harzburgite to accumulate in the mantle transition zone (MTZ) and/or the lower mantle. However, the key parameters that control basalt segregation and accumulation remain poorly constrained. Here, we use global-scale 2D thermochemical convection models to investigate the influence of mantle-viscosity profile, planetary-tectonic style and bulk composition on the evolution and distribution of mantle heterogeneity. Our models robustly predict that, for all cases with Earth-like tectonics, a basalt-enriched reservoir is formed in the MTZ, and a harzburgite-enriched reservoir is sustained at 660?800 km depth, despite ongoing whole-mantle circulation. The enhancement of basalt and harzburgite in and beneath the MTZ, respectively, are laterally variable, ranging from ?30% to 50% basalt fraction, and from ?40% to 80% harzburgite enrichment relative to pyrolite. Models also predict an accumulation of basalt near the core mantle boundary (CMB) as thermochemical piles, as well as moderate enhancement of most of the lower mantle by basalt. While the accumulation of basalt in the MTZ does not strongly depend on the mantle-viscosity profile (explained by a balance between basalt delivery by plumes and removal by slabs at the given MTZ capacity), that of the lowermost mantle does: lower-mantle viscosity directly controls the efficiency of basalt segregation (and entrainment) near the CMB; upper-mantle viscosity has an indirect effect through controlling slab thickness. Finally, the composition of the bulk-silicate Earth may be shifted relative to that of upper-mantle pyrolite, if indeed significant reservoirs of basalt exist in the MTZ and lower mantle.
DS202005-0772
2020
Yan, J.Yan, J., Ballmer, M.D., Tackley, P.J.The evolutiom and distribution of recycled oceanic crust in the Earth's mantle: insight from geodynamic models. ( harzburgite)Earth and Planetary Science Letters, Vol. 537, 116171, 12p. PdfMantlegeodynamics

Abstract: A better understanding of the Earth's compositional structure is needed to place the geochemical record of surface rocks into the context of Earth accretion and evolution. Cosmochemical constraints imply that lower-mantle rocks may be enriched in silica relative to upper-mantle pyrolite, whereas geophysical observations support whole-mantle convection and mixing. To resolve this discrepancy, it has been suggested that subducted mid-ocean ridge basalt (MORB) segregates from subducted harzburgite to accumulate in the mantle transition zone (MTZ) and/or the lower mantle. However, the key parameters that control basalt segregation and accumulation remain poorly constrained. Here, we use global-scale 2D thermochemical convection models to investigate the influence of mantle-viscosity profile, planetary-tectonic style and bulk composition on the evolution and distribution of mantle heterogeneity. Our models robustly predict that, for all cases with Earth-like tectonics, a basalt-enriched reservoir is formed in the MTZ, and a harzburgite-enriched reservoir is sustained at 660?800 km depth, despite ongoing whole-mantle circulation. The enhancement of basalt and harzburgite in and beneath the MTZ, respectively, are laterally variable, ranging from ?30% to 50% basalt fraction, and from ?40% to 80% harzburgite enrichment relative to pyrolite. Models also predict an accumulation of basalt near the core mantle boundary (CMB) as thermochemical piles, as well as moderate enhancement of most of the lower mantle by basalt. While the accumulation of basalt in the MTZ does not strongly depend on the mantle-viscosity profile (explained by a balance between basalt delivery by plumes and removal by slabs at the given MTZ capacity), that of the lowermost mantle does: lower-mantle viscosity directly controls the efficiency of basalt segregation (and entrainment) near the CMB; upper-mantle viscosity has an indirect effect through controlling slab thickness. Finally, the composition of the bulk-silicate Earth may be shifted relative to that of upper-mantle pyrolite, if indeed significant reservoirs of basalt exist in the MTZ and lower mantle.
DS202007-1131
2020
Yan, J.Chisenga, C., Van der Meijde, M., Yan, J., Fadel. I., Atekwana, E.A., Steffen, R., Ramotoroko, C.Gravity derived crustal thickness model of Botswana: its implication for the Mw 6.5 April 3, 2017, Botswana earthquake. Tectonophysics, Vol. 787, 228479 12p. PdfAfrica, Botswanageophysics - gravity

Abstract: Botswana experienced a Mw 6.5 earthquake on 3rd April 2017, the second largest earthquake event in Botswana's recorded history. This earthquake occurred within the Limpopo-Shashe Belt, ~350 km southeast of the seismically active Okavango Rift Zone. The region has no historical record of large magnitude earthquakes or active faults. The occurrence of this earthquake was unexpected and underscores our limited understanding of the crustal configuration of Botswana and highlight that neotectonic activity is not only confined to the Okavango Rift Zone. To address this knowledge gap, we applied a regularized inversion algorithm to the Bouguer gravity data to construct a high-resolution crustal thickness map of Botswana. The produced crustal thickness map shows a thinner crust (35-40 km) underlying the Okavango Rift Zone and sedimentary basins, whereas thicker crust (41-46 km) underlies the cratonic regions and orogenic belts. Our results also show localized zone of relatively thinner crust (~40 km), one of which is located along the edge of the Kaapvaal Craton within the MW 6.5 Botswana earthquake region. Based on our result, we propose a mechanism of the Botswana Earthquake that integrates crustal thickness information with elevated heat flow as the result of the thermal fluid from East African Rift System, and extensional forces predicted by the local stress regime. The epicentral region is therefore suggested to be a possible area of tectonic reactivation, which is caused by multiple factors that could lead to future intraplate earthquakes in this region.
DS2001-1277
2001
Yan, L.Yan, L., Lines, L.R.Seismic imaging and velocity analysis for an Alberta Foothills seismic survey.Geophysics, Vol. 66, No. 3, pp. 721-32.AlbertaGeophysics - seismic
DS201908-1826
2019
Yan, L-L.Yan, L-L., Zhang, K-J.Is exhumation of UHP terranes limited to low latitudes? ( coesite and diamond)Journal of Geodynamics, Vol. 130, pp. 41-56.GlobalUHP

Abstract: How the ultrahigh-pressure (UHP) terranes are exhumed to shallow levels but preserving intact relics of the UHP phase assemblages is among the most interesting but challenging topics in geosciences. We investigate all the paleolatitudes where the UHP terranes were exhumed. Our results show that all the UHP terranes in continental collision zones or oceanic accretionary wedges were exhumed within low latitudes (0°-30°), and the average paleolatitude for exhumations of the investigated 43 UHP terranes is ˜5.1° N. In contrast, those UHP xenoliths in mantle-derived igneous rocks could be brought to surface at higher paleolatitudes. Furthermore, the pattern of frequency for the UHP terranes exhumed at convergent boundaries is consistent with that of interglacial stages throughout the Earth history, indicating that the UHP exhumation is controlled by the climate and thus suggesting that the exhumed UHP terranes may be useful paleoclimate indicators.
DS200412-2166
2004
Yan, Q.Yan, Q., Hanson, A.D., Wang, Z., Druschke, P.A., Yan, Z., Wan, T.Neoproterozoic subduction and rifting on the northern margin of the Yangtze Platform: Redonia reconstruction.International Geology Review, Vol.46, 9, Sept. pp. 817-832.ChinaSubduction
DS201412-1000
2014
Yan, R.Yang, J-J., Fan, Z.F., Yu, C., Yan, R.Coseismic formation of eclogite facies cataclastic dykes at Yangkou in the Chinese Sulu UHP metamorphic belt.Journal of Metamorphic Geology, Vol. 32, 9, pp. 937-960.ChinaUHP
DS202003-0365
2019
Yan, S.Tang, S., Liu, H., Yan, S., Xu, X., Wu, W., Fan, J., Liu, J., Hu, C., Tu, L.A high sensitivity MEMS gravimeter with a large dynamic range. ( not specific to diamonds)Nature.com Microsystems & Nanoengineering, Vol. 5, doi:org/10.1038/ s41378-019-0089-7Globalgeophysics - gravity

Abstract: Precise measurement of variations in the local gravitational acceleration is valuable for natural hazard forecasting, prospecting, and geophysical studies. Common issues of the present gravimetry technologies include their high cost, high mass, and large volume, which can potentially be solved by micro-electromechanical-system (MEMS) technology. However, the reported MEMS gravimeter does not have a high sensitivity and a large dynamic range comparable with those of the present commercial gravimeters, lowering its practicability and ruling out worldwide deployment. In this paper, we introduce a more practical MEMS gravimeter that has a higher sensitivity of 8??Gal/?Hz and a larger dynamic range of 8000 mGal by using an advanced suspension design and a customized optical displacement transducer. The proposed MEMS gravimeter has performed the co-site earth tides measurement with a commercial superconducting gravimeter GWR iGrav with the results showing a correlation coefficient of 0.91.
DS2002-1753
2002
Yan, W.Xu, Y.G., Sun, M., Yan, W., Liu, Y., Huang, X.L., Chen, X.M.Xenolith evidence for polybaric melting and stratification of the upper mantle beneath South China.Journal of Asian Earth Sciences, Vol. 20,8, pp. 937-54.ChinaMelt - xenoliths
DS2003-1369
2003
Yan, Y.Teng, J., Zeng, R., Yan, Y.Depth distribution of Moho and tectonic framework in eastern Asian continent and itsScience in China Series d Earth Sciences, Vol. 46, 5, pp. 428-46.Asia, ChinaTectonics
DS200412-1978
2003
Yan, Y.Teng, J., Zeng, R., Yan, Y.Depth distribution of Moho and tectonic framework in eastern Asian continent and its adjacent ocean areas.Science China Earth Sciences, Vol. 46, 5, pp. 428-46.Asia, ChinaTectonics
DS200412-2166
2004
Yan, Z.Yan, Q., Hanson, A.D., Wang, Z., Druschke, P.A., Yan, Z., Wan, T.Neoproterozoic subduction and rifting on the northern margin of the Yangtze Platform: Redonia reconstruction.International Geology Review, Vol.46, 9, Sept. pp. 817-832.ChinaSubduction
DS1988-0779
1988
Yan BenjinZhang Wenkuan, Yan BenjinOre prospecting criteria and discriminant model for kimberlite typediamonds.*CHIMineral Deposits, *CHI, Vol. 7, No. 3, pp. 77-86. also noted as pp. 71-78ChinaKimberlite, Diamond genesis
DS1985-0749
1985
Yan binggangYan binggang, LIANG RIXUAN, Yang fengying, FANG QINGSONG.Some characters of diamond and diamond bearing ultramafic rocks in Xizang(Tibet).*CHI27th. International Geological Congress Held China**chi, pp. 341-350ChinaUltramafics, Diamond Genesis
DS1982-0648
1982
Yan binggang, SUN DESHO.Yan binggang, SUN DESHO.The Character of Diamonds in Ultrabasic Rocks in Xizang (tibet).Bulletin. Institute GEOL. (CHINESE ACAD. GEOL. SCI.), No. 5, P. 64.China, TibetDiamond Morphology
DS1991-0443
1991
Yan ChenEnkin, R.J., Yan Chen, Courtillot, V., Besse, J., Lisheng Xing, ZhenhaiA Cretaceous pole from South Chin a and the Mesozoic hairpin turn of the Eurasian apparent Polar wander pathJournal of Geophysical Research, Vol. 96, No. B3, March 10, pp. 4007-4027ChinaPaleomagnetism
DS1993-1789
1993
Yan ChenYan Chen, Courtillot, V., Cogne, J-P., Besse, J., Yang, Z., Enkin, R.The configuration of Asia prior to the collision of India: Cretaceous paleomagnetic constraints.Journal of Geophysical Research, Vol. 98, No. B 12, December 10, pp. 21, 927-21, 941.GlobalPaleomagnetics
DS1993-1089
1993
Yan GuohanMu Baolei, Yan GuohanGeochemical features of Triassic alkaline and subalkaline igneous complexes in the Yan-Liao area.Acta Geologica Sinica, Vol. 5, No. 4, pp. 339-356.ChinaAlkaline rocks, Geochemistry
DS2000-1037
2000
Yan LiuYan Liu, Zhong, D., Jiangqing Ji.Carbonatites in the eastern Himalayan syntaxis: a direct evidence for mantle magma upwelling Neogene ...Igc 30th. Brasil, Aug. abstract only 1p.India, HimalayasCarbonatite
DS201712-2701
2017
Yan Wang, C.Liu, Y-L., Ling, M-X., Williams, I.S., Yang, X-Y., Yan Wang, C., Sun, W.The formation of the giant Bayan Obo REE-Nb-Fe deposit, north China, Mesoproterozoic carbonatite and overprinted Palaeozoic dolomitization.Ore Geology Reviews, in press available, 47p.Chinadeposit - Bayan Obo

Abstract: The Bayan Obo ore deposit in Inner Mongolia, North China, the largest-known rare earth element (REE) deposit in the world, is closely associated with carbonatite dykes. Scarce zircon grains, with a wide range of ages and diverse origins, have been extracted from the Wu dyke, a REE-enriched calcitic carbonatite dyke 2?km from the East Ore Body of the Bayan Obo deposit. Three zircon populations were identified based on ages and trace element compositions: 1) Captured zircons with Paleoproterozoic and Archean ages. These zircons have REE patterns and moderate Th/U ratios similar to zircon with silicate inclusions from basement igneous rocks, which have been recognized as contaminants from wall rocks. 2) Carbonatite magmatic zircons with Mesoproterozoic ages. These zircons have high to extremely high Th/U ratios (13-1600), a characteristic signature of the Bayan Obo deposit. Two zircon grains yielded concordant 206Pb/238U ages (1.27?±?0.11?Ga???1.42?±?0.18?Ga) and 208Pb/232Th age (1.26?±?0.20?Ga) with calcite inclusions, indicating that the Wu dyke was emplaced at ca. 1.34?Ga, which coincides with a worldwide generation of Mesoproterozoic kimberlites, lamprophyres, carbonatites, and anorogenic magmatism. 3) Hydrothermal zircons with Caledonian and Triassic ages. The Caledonian zircon has 206Pb/238U age of 381?±?4?Ma and 208Pb/232Th age of 367?±?14?Ma with dolomite inclusion. These evidences are consistent with multiple stages of mineralization, Mesoproterozoic calcite carbonatite magmatism interacted by protracted fluxing of subduction-released Caledonian fluids during the closure of the Palaeo-Asian Ocean, coupled with interaction with the mantle wedge and metasomatism of overlying sedimentary carbonate.
DS201812-2844
2018
Yan Wang, C.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.
DS202205-0677
2022
Yan Wang, C.Chen, C., Yao, Z-S., Yan Wang, C.Partitioning behaviours of cobalt and manganese along diverse melting paths of peridotitic and MORB-like pyroxenite mantle.Journal of Petrology, Vol. 63, 4, 10.1093/perology/egac021Mantleperidotite

Abstract: The Co, Mn, Fe, and Ni contents of olivine phenocrysts and host basalts are sensitive to source mantle lithology, which suggests they may be used to constrain the processes of mantle melting and identify basalts formed from non-peridotitic (i.e. pyroxenitic) mantle sources. Here, we use a new comprehensive, forward model involving multiple parameters to simulate partitioning of Co and Mn during partial melting of the mantle in different tectonic settings: (1) polybaric continuous melting of peridotite mantle in mid-ocean ridges can generate melts that show decreasing Co and Mn with increasing degrees of melting so that the mid-ocean ridge basalts (MORBs) contain ~39-84 ?g/g Co and?~900-1600 ?g/g Mn; (2) flux-melting of the mantle wedge in subduction zones tends to produce a melt that has Co increasing from ~24 to 55 ?g/g and Mn from ~500 to 1110 ?g/g with increasing temperature; (3) melts produced by isobaric melting of the subcontinental lithospheric mantle are also sensitive to increasing temperature and have ~35-160 ?g/g Co and ~800-2600 ?g/g Mn; (4) decompression melting of peridotite related to the mantle plume generates melts containing ~45-140 ?g/g Co and?~1000-2000 ?g/g Mn, and the abundances of these metals decrease with increasing degrees of melting; and (5) partitioning behaviors of Co, Mn, and Ni during decompression melting of MORB-like pyroxenite contrast with those during decompression melting of peridotite due to the different mineralogy and compositions in mantle lithologies, and the MORB-like pyroxenite-derived melt is metal-poor with ~25-60 ?g/g Co, ~290-1600 ?g/g Mn, and?~160-340 ?g/g Ni. Although high-Ni, low-Mn forsteritic olivine phenocrysts and high melt Fe/Mn ratio have been proposed as diagnostic indicators of pyroxenitic components in the mantle, our models show that these features can be also generated by melting of peridotite at greater depth (i.e. a high pressure and temperature). To quantify the effect of high-pressure melting of peridotite on these diagnostic indicators, we modeled the correlations of melt Fe/Mn and olivine Co, Mn, and Ni contents with melting depth along the decompression melting path of a thermal plume. When Fe/Mn ratios of basalts and/or compositions of olivine phenocrysts deviate significantly from our modeled correlation lines, high-pressure melting of peridotite cannot explain these data, and the existence of pyroxenitic component in the mantle source is likely required. The pyroxenite-derived melt is modeled to be Ni-poor, but mixing with a peridotite-derived melt can strongly increase the partition coefficient of Ni between olivine and mixed melt, resulting in the generation of high-Ni olivine phenocrysts in plume-associated magmatic suites.
DS201412-0186
2014
Yan Wong, S.D'Haenens-Johansson, U.F.S., Soe Moe, K., Johnson, P., Yan Wong, S., Lu, R., Wang, W.Near-colorless HPHT synthetic diamonds from AOTC group.Gems & Gemology, Vol. 50, 1, Spring, pp. 30-45.TechnologySynthetic diamonds
DS1990-1606
1990
Yan YaoyangYan Yaoyang, Zhang YijunThe lower Proterozoic metamorphosed impure carbonatites southernJilin.*CHIJilin Geology, *CHI, Vol. 9, No. 4, pp. 34-39ChinaCarbonatite, Petrology
DS200412-2167
2004
Yanagawa, T.K.Yanagawa, T.K., Nakada, M., Yuen, D.A.A simplified mantle convection model for thermal conductivity stratification.Physics of the Earth and Planetary Interiors, Vol. 146, 1-2, pp. 163-177.MantleGeothermometry
DS201810-2359
2018
Yanagi, R.Nakagawa, T., Iwamori, H., Yanagi, R., Nako, A.On the evolutiom of the water ocean in the plate mantle system.Progress in Earth and Planetary Science, Vol. 5, pp. 51- 16p.Mantlewater

Abstract: Here, we investigate a possible scenario of surface seawater evolution in the numerical simulations of surface plate motion driven by mantle dynamics, including thermo-chemical convection and water migration, from the early to present-day Earth to constrain the total amount of water in the planetary system. To assess the validity of two hypotheses of the total amount of water inferred from early planetary formation processes and mineral physics, we examine the model sensitivity to the total water in the planetary system (both surface and deep interior) up to 15 ocean masses. To explain the current size of the reservoir of surface seawater, the predictions based on the numerical simulations of hydrous mantle convection suggest that the total amount of water should range from 9 to 12 ocean masses. Incorporating the dense hydrous magnesium silicate (DHMS) with a recently discovered hydrous mineral at lower mantle pressures (phase H) indicates that the physical mechanism of the mantle water cycle would not be significantly influenced, but the water storage region would be expanded in addition to the mantle transition zone. The DHMS solubility field may have a limited impact on the partitioning of water in the Earth’s deep mantle.
DS1994-1960
1994
Yanagi, T.Yanagi, T., Yamashita, K.Genesis of continental crust under arc conditionsLithos, Vol. 33, pp. 209-233MantleVolcanics, Subduction - arcs
DS1996-1575
1996
Yanamoto, J.K.Yanamoto, J.K.Ore reserve estimation.. a new method of block calculation using the inverse of weighted distanceEngineering and Mining Journal, Vol. 197, No. 9, Sept. p. 69-70, 72GlobalOre reserves, geostatistics, Kriging
DS2002-0288
2002
Yanamoto, T.Chigai, T., Yanamoto, T., Kozasa, T.Heterogeneous condensation of presolar titanium carbide core graphite mantle spherules.Meteoritics and Planetary Science, Vol. 37, 12, p. 1937-52.MantleGraphite
DS1992-1714
1992
Yanbin WangYanbin Wang, Guyot, F., Liebermann, R.C.Electron microcopy of (magnesium, iron) SiO3 perovskite: evidence for structural phase transitions and implications for the lower mantleJournal of Geophysical Research, Vol. 97, No. B9, August 10, pp. 12, 327-12, 347MantlePerovksite
DS1999-0698
1999
Yanev, Y.Sparks, R.S.J., Tait, S.R., Yanev, Y.Dense welding caused by volatile resorptionJournal of Geological Society of London, Vol. 156, No. 2, Mar. pp. 217-26.GlobalMagmatism - volconology
DS2002-1759
2002
Yanez, G.Yanez, G., Cembrano, J., Pardo, M., Ranero, C., SellesThe Challinger Juan Fernadex Maipo major tectonic transition of the Nazca Andean subduction system 33-34Journal of South American Earth Sciences, Vol.15,1,Apr.pp.23-38.Chile, AndesSubduction, Geodynamic evidence and implications
DS1995-0431
1995
Yanez, G.P.Dohrenwend, J.C., Yanez, G.P., Lowry, G.Cenozoic Lands cape evolution of the southern part of the Gran Sabana, southeastern Venezuela -implicationsUnited States Geological Survey (USGS) Bulletin., No. 2124-A, pp. K1-17.VenezuelaRoraima Group, laterites, paleoplacers, Placers, alluvials
DS1990-1635
1990
YangZhou Xiuzhong, Huang Yunhaui, Qin Shuying, Deng Chujun, Gao Yan, YangStudies on the type and the typomorphic characteristics of the garnets From kimberlites and the relationship between the garnets and diamondInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 1, extended abstract p. 141-142ChinaMineralogy -garnets, Diamond morphology
DS1993-1790
1993
YangYang, Jianjun, Godard, G., Kienast, J-R., Yongzheng Lu, JinxiongUltrahigh pressure ( 60 Kbar) magnesite-bearing garnet peridotites from northeastern Jiangsu, China.Journal of Geology, Vol. 101, No. 5, September pp. 541-554.ChinaEclogites, Shandong Province
DS2002-0957
2002
YangLiu, F., Xu, Z., Liu, J.G., Katayama, Masago, Maruyama, YangUltra high pressure mineral inclusions in zircons from gneissic core samples of the Chinese continental drilling site in eastern China.European Journal of Mineralogy, No. 3, pp. 499-512.China, easternUHP, Mineral inclusions
DS200612-1560
2006
YangXu, Z., Wang, Q., Ji, S., Chen, J., Zeng, Yang, Chen, Liang, WenkPetrofabrics and seismic properties of garnet peridotite from the UHP Sulu terrane: implications for olivine deformation mechanism in subducting slab.Tectonophysics, Vol. 421, 1-2, pp. 111-127.MantleSubduction - cold, dry continental slab
DS200812-1172
2008
YangTian, S., Hou, Ding, Yang, Yang, Yuan, Xie, Liu, Li.Ages of carbonatite and syenite from the Mianning Dechang REE belt in eastern Indo-Asian collision zone, SW Chin a and their geological significance.Goldschmidt Conference 2008, Abstract p.A947.ChinaCarbonatite
DS200812-1172
2008
YangTian, S., Hou, Ding, Yang, Yang, Yuan, Xie, Liu, Li.Ages of carbonatite and syenite from the Mianning Dechang REE belt in eastern Indo-Asian collision zone, SW Chin a and their geological significance.Goldschmidt Conference 2008, Abstract p.A947.ChinaCarbonatite
DS200812-1292
2008
YangYang, 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
DS201112-0567
2011
YangLan, T-G., Fan, H-R., Santosh, M., Hu, F-F., Yang, Y-H, Liu, Y.Geochemistry and Sr Nd Pb Hf isotopes of the Mesozoic Dadian alkaline intrusive complex in the Sulu orogenic belt, eastern China: implications for crust mantle interaction.Chemical Geology, Vol. 285, 1-4, pp. 97-114.ChinaAlkalic
DS201112-1133
2011
YangYang, K-F, Fan, H-R., Santosh, M., Hu, F-F., Wang, K-Y.Mesoproterozoic carbonatitic magmatism in the Bayan Obo deposit, Inner Mongolia, North China: constraints for the mechanism of super accumulation of rare earth elements.Ore Geology Reviews, in press available 10p.ChinaCarbonatite, REE
DS201510-1789
2015
YangMoe, K.S., Yang, J-S, Johnson, P., Xu, X., Wang, W.Microdiamonds in chromitite and peridotite. Type 1aB and 1bGSA Annual Meeting, Paper 300-5, 1p. Abstract only BoothRussiaSpectroscopy
DS201511-1827
2015
YangCai, Y-C., Fan, H-R., Santsh, M., Hu, F-F., Yang, K-F, Hu, Z.Subduction related metasomatism of the lithospheric mantle beneath the southeastern North Chin a Craton: evidence from mafic to intermediate dykes in the northern Sulu orogen.Tectonophysics, Vol. 659, pp. 137-151.ChinaSulu orogen - dykes

Abstract: The widespread mafic to intermediate dykes in the northern Sulu orogen provide important constrains on mantle source characteristics and geodynamic setting. Here we present LA-ICPMS zircon U-Pb ages which indicate that the dykes were emplaced during Early Cretaceous (~ 113-108 Ma). The rocks show SiO2 in the range of 46.2 to 59.5 wt.% and alkalic and shoshonitic affinity with high concentrations of MgO (up to 7.6 wt.%), Cr (up to 422 ppm) and Ni (up to 307 ppm). They are enriched in light rare earth elements LREE (La, Ce, Pr, Nd, Sm and Eu) and large ion lithophile elements (LILE, Rb, Sr, Ba, U and Th) and show strong depletion in high field strength elements (HFSE, Nb, Ta, Ti and P). The dykes possess uniformly high (87Sr/86Sr)i (0.70824-0.70983), low ?Nd(t) (? 14.0 to ? 17.4) and (206Pb/204Pb)i (16.66-17.02) and negative ?Hf(t) (? 23.5 to ? 13.7). Our results suggest that the source magma did not undergo any significant crustal contamination during ascent. The systematic variation trends between MgO and major and trace elements suggest fractionation of olivine and clinopyroxene. The highly enriched mantle source for these rocks might have involved melts derived from the subducted lower crust of Yangtze Craton that metasomatized the ancient lithospheric mantle of the North China Craton.
DS202002-0203
2020
YangLiu, 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.
DS201312-0989
2013
Yang, A.Q.Yang, A.Q., Zeng, Z-j., Zheng, X-q., Hu, Y-l.Emplacement age and Sr-Nd isotopic compositions of the AfrikAnd a alkaline ultramafic complex, Kola Peninsula, Russia.Spectroscopy and Spectral Analysis, Vol. 33, 9, pp. 2374-2378.ChinaDeposit - Mengyin
DS201312-0738
2014
Yang, B.B.Refayee, H.A., Yang, B.B., Liu, K.H., Gao, S.S.Mantle flow and lithosphere asthenosphere coupling beneath the southwestern edge of the North American craton: constraints from shear wave splitting measurements.Earth and Planetary Science Letters, Vol. 402, pp. 209-220.CanadaAnisotropy
DS2000-0427
2000
Yang, C.Hutcheon, I., Cody, J., Yang, C.Fluid flow in the Western Canada Sedimentary Basin - a biased perspective based on geochemistry.Kyser: Fluids and Basin Evolution, Sc 28, pp. 197-210.Alberta, Western Canada Sedimentary BasinBasin - geochemistry
DS202009-1676
2020
Yang, C.Zheng, H., Chen, H., Wu, C., Jiang, H., Gao, C., Kang, Q., Yang, C., Wang, D., Lai, C-K.Genesis of the supergiant Huayangchuan carbonatite-hosted uranium polymetallic deposit in the Qinling orogen, central China.Gondwana Research, Vol. 86, pp. 250-265.ChinaREE

Abstract: The newly-discovered supergiant Huayangchuan uranium (U)-polymetallic deposit is situated in the Qinling Orogen, Central China. The deposit contains economic endowments of U, Nb, Pb, Se, Sr, Ba and REEs, some of which (e.g., U, Se, and Sr) reaching super-large scale. Pyrochlore, allanite, monazite, barite-celestite and galena are the major ore minerals at Huayangchuan. Uranium is mainly hosted in the primary mineral of pyrochlore, and the mineralization is mainly hosted in or associated with carbonatite dikes. According to the mineral assemblages and crosscutting relationships, the alteration/mineralization at Huayangchuan comprises four stages, i.e., pegmatite REE mineralization (I), main mineralization (II), skarn mineralization (III) and post-ore alteration (IV). Coarse-grained euhedral allanite is the main Stage I REE mineral, and the pegmatite-hosted REE mineralization (ca. 1.8 Ga) occurs mostly in the shallow-level of northwestern Huayangchuan, corresponding to the Paleoproterozoic Xiong'er Group volcanic rocks (1.80-1.75 Ga) in the southern margin of North China Block. Carbonatite-hosted Stage II mineralization contributes to the majority of U-Nb-REE-Ba-Sr resources, and is controlled by the Huayangchuan Fault. Stage II mineralization can be further divided into the sulfate mineralization (barite-celestite) (II-A), alkali-rich U mineralization (aegirine-augite + pyrochlore + uraninite + uranothorite) (II-B) and REE (allanite + monazite + chevkinite)-U (pyrochlore + uraninite) mineralization (II-C) substages. Stage II mineralization may have occurred during the Late Triassic Mianlue Ocean closure. Skarn mineralization contributed to the majority of Pb and minor U-REE (uraninite-allanite) resources at Huayangchuan, and is spatially associated with the Late Cretaceous-Early Jurassic (Yanshanian) Huashan and Laoniushan granites. We suggested that hydrothermal fluids derived from the Laoniushan and Huashan granites may have reacted with the Triassic carbonatites, and formed the Huayangchuan Pb skarn mineralization. The mantle-derived Triassic carbonatites may have been fertilized by the U-rich subducting oceanic sediments, and were further enriched through reacting with the Proterozoic U-REE-rich pegmatite wallrocks at Huayangchuan. Ore-forming elements were likely transported in metal complexes (F?, and ), and deposited with the dilution of the complex concentration. This may have formed the distinct vertical mineralization zoning, i.e., sodic fenite-related alkali-U mineralization at depths and potassic fenite-related REE-U mineralization at shallow level.
DS202012-2242
2020
Yang, C.Qin, L., Yang, C.Magnetotelluric soundings on a stratified Earth with two transitional layers.Pure and Applied Physics, Vol. 177, pp. 5263-5274.Mantlegeophysics - magnetics

Abstract: Theoretical magnetotelluric (MT) soundings are investigated for a stratified (five-layered) Earth model consisting of two transitional layers with conductivity varying linearly with depth, and three homogeneous layers with constant conductivity. The analytical expressions for the tangential electric and magnetic fields as well as the surface impedance are derived in terms of Airy functions. The effect of the thicknesses of the two transitional layers and the interlayer between them on the MT responses (apparent resistivity and impedance phase) is examined in detail.
DS202012-2258
2020
Yang, C.Zheng, H., Chen, H., Wu, C., Jiang, H., Gao, C., Kang, Q., Yang, C., Wang, D., Lai, C-k.Genesis of the supergiant Huayanchuan carbonatite-hosted uranium-plymetallic deposit in the Qinling Orogen, central China.Gondwana Research, Vol. 86, pp. 250-265. pdfChinadeposit - Huayangchuan

Abstract: The newly-discovered supergiant Huayangchuan uranium (U)-polymetallic deposit is situated in the Qinling Orogen, Central China. The deposit contains economic endowments of U, Nb, Pb, Se, Sr, Ba and REEs, some of which (e.g., U, Se, and Sr) reaching super-large scale. Pyrochlore, allanite, monazite, barite-celestite and galena are the major ore minerals at Huayangchuan. Uranium is mainly hosted in the primary mineral of pyrochlore, and the mineralization is mainly hosted in or associated with carbonatite dikes. According to the mineral assemblages and crosscutting relationships, the alteration/mineralization at Huayangchuan comprises four stages, i.e., pegmatite REE mineralization (I), main mineralization (II), skarn mineralization (III) and post-ore alteration (IV). Coarse-grained euhedral allanite is the main Stage I REE mineral, and the pegmatite-hosted REE mineralization (ca. 1.8 Ga) occurs mostly in the shallow-level of northwestern Huayangchuan, corresponding to the Paleoproterozoic Xiong'er Group volcanic rocks (1.80-1.75 Ga) in the southern margin of North China Block. Carbonatite-hosted Stage II mineralization contributes to the majority of U-Nb-REE-Ba-Sr resources, and is controlled by the Huayangchuan Fault. Stage II mineralization can be further divided into the sulfate mineralization (barite-celestite) (II-A), alkali-rich U mineralization (aegirine-augite + pyrochlore + uraninite + uranothorite) (II-B) and REE (allanite + monazite + chevkinite)-U (pyrochlore + uraninite) mineralization (II-C) substages. Stage II mineralization may have occurred during the Late Triassic Mianlue Ocean closure. Skarn mineralization contributed to the majority of Pb and minor U-REE (uraninite-allanite) resources at Huayangchuan, and is spatially associated with the Late Cretaceous-Early Jurassic (Yanshanian) Huashan and Laoniushan granites. We suggested that hydrothermal fluids derived from the Laoniushan and Huashan granites may have reacted with the Triassic carbonatites, and formed the Huayangchuan Pb skarn mineralization. The mantle-derived Triassic carbonatites may have been fertilized by the U-rich subducting oceanic sediments, and were further enriched through reacting with the Proterozoic U-REE-rich pegmatite wallrocks at Huayangchuan. Ore-forming elements were likely transported in metal complexes (F?, and ), and deposited with the dilution of the complex concentration. This may have formed the distinct vertical mineralization zoning, i.e., sodic fenite-related alkali-U mineralization at depths and potassic fenite-related REE-U mineralization at shallow level.
DS202202-0219
2022
Yang, C.Y.Tan, W., Qin, X., Liu, J., Zhou, M-F., He, H., Yang, C.Y., Huang, J., Zhu, J., Yao, Y., Cudahy, T.Feasibility of visible short-wave infrared reflectance spectroscopy to characterize regolith-hosted rare earth element mineralization.Economic Geology, Vol. 117, 3, pp. 485-494.Chinadeposit - Renju

Abstract: Regolith-hosted rare earth element (REE) deposits predominate global resources of heavy REEs. Regoliths are underlain by various types of igneous rocks and do not always host economically valuable deposits. Thus a feasible and convenient method is desired to identify REE mineralization in a particular regolith. This study presents a detailed visible short-wave infrared reflectance (VSWIR) spectroscopic study of the Renju regolith-hosted REE deposit, South China, to provide diagnostic parameters for targeting REE orebodies in regoliths. The results show that the spectral parameters, M794_2nd and M800_2nd, derived from the VSWIR absorption of Nd3+ at approximately 800 nm, can be effectively used to estimate the total REE concentrations in regolith profiles. M1396_2nd/M1910_2nd ratios can serve as proxies to evaluate weathering intensities in a regolith. Abrupt changes of specific spectral features related to mineral abundances, chemical compositions, and weathering intensities can be correlated with variations of protolith that formed a regolith. These VSWIR proxies are robust and can be used for exploration of regolith-hosted REE deposits.
DS201911-2564
2019
Yang, C-X.Snatish, M., Tsunogae, T., Yang, C-X., Han, Y-S., Hari, K.R., Prasanth, M., Uthup, S.The Bastar craton, central India: a window to Archean-paleoproterozoic crustal evolution.Gondwana Research, in press available 69p. PdfIndiacraton

Abstract: The Bastar craton in central India, surrounded by cratonic blocks and Paleoproterozoic to Neoproterozoic orogenic belts, is a window to investigate the Archean-Paleoproterozoic crustal evolution and tectonic processes. Here we propose a new tectonic classification of the craton into the Western Bastar Craton (WBC), Eastern Bastar Craton (EBC), and the intervening Central Bastar Orogen (CBO). We present petrologic, geochemical and zircon U-Pb, REE and Lu-Hf data from a suite of rocks from the CBO and along the eastern margin of the WBC Including: (1) volcanic successions comprising meta-andesite and fine-grained amphibolite, representing arc-related volcanics along a convergent margin; (2) ferruginous sandstone, in association with rhyolite, representing a volcano-sedimentary succession, deposited in an active trench; and (3) metamorphosed mafic-ultramafic suite including gabbro, pyroxenite and dunite invaded by trondhjemite representing the section of sub-arc mantle and arc root adjacent to a long-lasting subduction system. Petrologic studies indicate that the mafic-ultramafic suite crystallized from an island arc tholeiitic parental magma in a suprasubduction zone environment. The chondrite-normalized and primitive mantle normalized diagrams of the mafic and ultramafic rocks suggest derivation from MORB magma. The mixed characters from N-MORB to E-MORB of the studied samples are consistent with subduction modification of a MORB related magma, involving partial melting of the metasomatized mantle wedge. Our zircon U-Pb age data suggest that the cratonic nuclei was constructed as early as Paleoarchean. We present evidence for active subduction and arc magmatism through Mesoarchean to Neoarchean and early Paleoproterozoic, with the trench remaining open until at least 2.3 Ga. Two major crust building events are recognized in the Bastar craton: during Mesoarchean (recycled Paleoarchean subduction-related as well as juvenile/depleted mantle components) and Neoarchean (accretion of juvenile oceanic crust, arc magmatism including granite batholiths and related porphyry mineralization). The final cratonization occurred during latest Paleoproterozoic, followed by collisional assembly of the craton and its incorporation within the Peninsular Indian mosaic during Mesoproterozoic. In the global supercontinent context, the craton preserves the history of Ur, the earliest supercontinent, followed by the Paleo-Mesoproterozoic Columbia, as well as minor thermal imprints of the Neoproterozoic Rodinia and associated Grenvillian orogeny.
DS202001-0037
2020
Yang, C-X.Santosh, M., Tsunogae, T., Yang, C-X., Han, T-S., Hari, K.R., Prasanth, M.P.M., Uthup, S.The Bastar craton, central India: a window to Archean - Paleoproterozic crustal evolution.Gondwana Research, Vol. 79, pp. 157-184.Indiacraton

Abstract: The Bastar craton in central India, surrounded by cratonic blocks and Paleoproterozoic to Neoproterozoic orogenic belts, is a window to investigate the Archean-Paleoproterozoic crustal evolution and tectonic processes. Here we propose a new tectonic classification of the craton into the Western Bastar Craton (WBC), Eastern Bastar Craton (EBC), and the intervening Central Bastar Orogen (CBO). We present petrologic, geochemical and zircon U-Pb, REE and Lu-Hf data from a suite of rocks from the CBO and along the eastern margin of the WBC Including: (1) volcanic successions comprising meta-andesite and fine-grained amphibolite, representing arc-related volcanics along a convergent margin; (2) ferruginous sandstone, in association with rhyolite, representing a volcano-sedimentary succession, deposited in an active trench; and (3) metamorphosed mafic-ultramafic suite including gabbro, pyroxenite and dunite invaded by trondhjemite representing the section of sub-arc mantle and arc root adjacent to a long-lasting subduction system. Petrologic studies indicate that the mafic-ultramafic suite crystallized from an island arc tholeiitic parental magma in a suprasubduction zone environment. The chondrite-normalized and primitive mantle normalized diagrams of the mafic and ultramafic rocks suggest derivation from MORB magma. The mixed characters from N-MORB to E-MORB of the studied samples are consistent with subduction modification of a MORB related magma, involving partial melting of the metasomatized mantle wedge. Our zircon U-Pb age data suggest that the cratonic nuclei was constructed as early as Paleoarchean. We present evidence for active subduction and arc magmatism through Mesoarchean to Neoarchean and early Paleoproterozoic, with the trench remaining open until at least 2.3?Ga. Two major crust building events are recognized in the Bastar craton: during Mesoarchean (recycled Paleoarchean subduction-related as well as juvenile/depleted mantle components) and Neoarchean (accretion of juvenile oceanic crust, arc magmatism including granite batholiths and related porphyry mineralization). The final cratonization occurred during latest Paleoproterozoic, followed by collisional assembly of the craton and its incorporation within the Peninsular Indian mosaic during Mesoproterozoic. In the global supercontinent context, the craton preserves the history of Ur, the earliest supercontinent, followed by the Paleo-Mesoproterozoic Columbia, as well as minor thermal imprints of the Neoproterozoic Rodinia and associated Grenvillian orogeny.
DS202003-0361
2020
Yang, C-X.Santosh, M., Tsunogae, T., Yang, C-X., Han, Y-S., Hari, K.R., Manu Prasanth, M.P., Uthup, S.The Bastar craton, central India: a window to Archean - Paleoproterozoic crustal evolution.Gondwana Research, Vol. 79, pp. 157-184.Indiacraton

Abstract: The Bastar craton in central India, surrounded by cratonic blocks and Paleoproterozoic to Neoproterozoic orogenic belts, is a window to investigate the Archean-Paleoproterozoic crustal evolution and tectonic processes. Here we propose a new tectonic classification of the craton into the Western Bastar Craton (WBC), Eastern Bastar Craton (EBC), and the intervening Central Bastar Orogen (CBO). We present petrologic, geochemical and zircon U-Pb, REE and Lu-Hf data from a suite of rocks from the CBO and along the eastern margin of the WBC Including: (1) volcanic successions comprising meta-andesite and fine-grained amphibolite, representing arc-related volcanics along a convergent margin; (2) ferruginous sandstone, in association with rhyolite, representing a volcano-sedimentary succession, deposited in an active trench; and (3) metamorphosed mafic-ultramafic suite including gabbro, pyroxenite and dunite invaded by trondhjemite representing the section of sub-arc mantle and arc root adjacent to a long-lasting subduction system. Petrologic studies indicate that the mafic-ultramafic suite crystallized from an island arc tholeiitic parental magma in a suprasubduction zone environment. The chondrite-normalized and primitive mantle normalized diagrams of the mafic and ultramafic rocks suggest derivation from MORB magma. The mixed characters from N-MORB to E-MORB of the studied samples are consistent with subduction modification of a MORB related magma, involving partial melting of the metasomatized mantle wedge. Our zircon U-Pb age data suggest that the cratonic nuclei was constructed as early as Paleoarchean. We present evidence for active subduction and arc magmatism through Mesoarchean to Neoarchean and early Paleoproterozoic, with the trench remaining open until at least 2.3?Ga. Two major crust building events are recognized in the Bastar craton: during Mesoarchean (recycled Paleoarchean subduction-related as well as juvenile/depleted mantle components) and Neoarchean (accretion of juvenile oceanic crust, arc magmatism including granite batholiths and related porphyry mineralization). The final cratonization occurred during latest Paleoproterozoic, followed by collisional assembly of the craton and its incorporation within the Peninsular Indian mosaic during Mesoproterozoic. In the global supercontinent context, the craton preserves the history of Ur, the earliest supercontinent, followed by the Paleo-Mesoproterozoic Columbia, as well as minor thermal imprints of the Neoproterozoic Rodinia and associated Grenvillian orogeny.
DS201412-0184
2014
Yang, D.Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne dat a sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, pp. 1790-1794 extended abstractCanada, Northwest TerritoriesGeophysics - Tli Kwi Cho
DS201412-0250
2014
Yang, D.Fournier, D., Heagy, L., Corcoran, N., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, pp. 1795-1798. Extended abstractCanada, Northwest TerritoriesGeophysics - Tli Kwi Cho complex
DS201501-0006
2014
Yang, D.Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne dat a sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, 5p. Extended abstractCanada, Northwest TerritoriesDeposit - Tli Kwi Cho, geophysics

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three papers. In the first, we find a 3D magnetic susceptibility model for the area; in the second, we find a 3D conductivity model; and in the third paper, we find a 3D chargeability model. Our goal is to explain all the geophysical results within a geologic framework. In this first paper, we invert three independent airborne magnetic data sets flown over the Tli Kwi Cho kimberlite complex located in the Lac de Gras kimberlite field in Northwest Territories, Canada. The complex consists of two kimberlites known as DO-27 and DO-18. An initial airborne DIGHEM survey was flown in 1992 and AeroTEM and VTEM data subsequently acquired in 2003 and 2004, respectively. In this paper, we invert each magnetic data set in three dimensions. Both kimberlites are recovered in each model, with DO-27 as a more susceptible body than DO-18. Our goal is to simultaneously invert the three data sets to generate a single susceptibility model for Tli Kwi Cho. This project is part of a larger, on-going investigation by UBC-GIF on inverting magnetic, electromagnetic, and induced polarization data from the Tli Kwi Cho area.
DS201501-0009
2014
Yang, D.Fournier, D., Heagy, L., Corcoran, N., Cowan, D., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, 5p. Extended abstractCanada, Northwest TerritoriesDeposit - Tli Kwi Cho, geophysics

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three posters. In the first we find a 3D magnetic susceptibility model for the area; in the second we find a 3D conductivity model; and in the third we find a 3D chargeability model that can explain the negative transient responses measured over the kimberlite pipes. In this second paper we focus upon the task of finding a conductivity model that is compatible with three airborne data sets flown between 1992 and 2004: one frequency-domain data set (DIGHEM) and two time-domain systems (AeroTEM and VTEM). The goal is to obtain a 3D model from which geologic questions can be answered, but even more importantly, to provide a background conductivity needed to complete the 3D IP inversion of airborne EM data. We begin by modifying our pre-existing 1D frequency and time domain inversion codes to produce models that have more lateral continuity. The results are useful in their own right but we have also found that 1D analysis is often very effective in bringing to light erroneous data, assisting in estimating noise floors, and providing some starting information for developing a background model for the 3D EM inversion. Here we show some results from our Laterally Constrained Inversion (LCI) framework. The recovered conductivity models seem to agree on the general location of the kimberlite pipes but disagree on the geometry and conductivity values at depth. The complete 3D inversions in time and frequency, needed to resolved these issues, are currently in progress.
DS201611-2103
2014
Yang, D.Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne dat a sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, pp. 1790-1794. pdfCanada, Northwest TerritoriesDeposit - Tli Kwi Cho

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three papers. In the first, we find a 3D magnetic susceptibility model for the area; in the second, we find a 3D conductivity model; and in the third paper, we find a 3D chargeability model. Our goal is to explain all the geophysical results within a geologic framework. In this first paper, we invert three independent airborne magnetic data sets flown over the Tli Kwi Cho kimberlite complex located in the Lac de Gras kimberlite field in Northwest Territories, Canada. The complex consists of two kimberlites known as DO-27 and DO- 18. An initial airborne DIGHEM survey was flown in 1992 and AeroTEM and VTEM data subsequently acquired in 2003 and 2004, respectively. In this paper, we invert each magnetic data set in three dimensions. Both kimberlites are recovered in each model, with DO-27 as a more susceptible body than DO-18. Our goal is to simultaneously invert the three data sets to generate a single susceptibility model for Tli Kwi Cho. This project is part of a larger, on-going investigation by UBC-GIF on inverting magnetic, electromagnetic, and induced polarization data from the Tli Kwi Cho area.
DS201611-2107
2014
Yang, D.Fournier, D., Heagy, L., Corcoran, N., Cowan, D., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Marchant, M., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, pp. 1795-1799. pdfCanada, Northwest TerritoriesDeposit - Tli Kwi Cho

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three posters. In the first we find a 3D magnetic susceptibility model for the area; in the second we find a 3D conductivity model; and in the third we find a 3D chargeability model that can explain the negative transient responses measured over the kimberlite pipes. In this second paper we focus upon the task of finding a conductivity model that is compatible with three airborne data sets flown between 1992 and 2004: one frequency-domain data set (DIGHEM) and two time-domain systems (AeroTEM and VTEM). The goal is to obtain a 3D model from which geologic questions can be answered, but even more importantly, to provide a background conductivity needed to complete the 3D IP inversion of airborne EM data. We begin by modifying our pre-existing 1D frequency and time domain inversion codes to produce models that have more lateral continuity. The results are useful in their own right but we have also found that 1D analysis is often very effective in bringing to light erroneous data, assisting in estimating noise floors, and providing some starting information for developing a background model for the 3D EM inversion. Here we show some results from our Laterally Constrained Inversion (LCI) framework. The recovered conductivity models seem to agree on the general location of the kimberlite pipes but disagree on the geometry and conductivity values at depth. The complete 3D inversions in time and frequency, needed to resolved these issues, are currently in progress.
DS200812-1282
2008
Yang, D.B.Xu, W-L., Yang, D.B., Gao, S., Yu, Y., Pei, F.P.Mesozoic lithospheric mantle of the Central North Chin a craton: evidence from peridotite xenoliths.Goldschmidt Conference 2008, Abstract p.A1047.ChinaXenoliths
DS201112-1129
2011
Yang, D.B.Xu,L., Zhou, Q.J., Pei, F.P., Yang, D.B., Gao, S., Wang, W., Feng, H.Recycling lower continental crust in an intra continental setting: mineral chemistry and oxygen isotope insights from websterite xenoliths.Goldschmidt Conference 2011, abstract p.2197.ChinaNorth China craton
DS200812-1290
2008
Yang, F.Yang, F., Liu, B., Ni, S., Zeng, X., Dai, Z., Li, Y.Lowermost mantle shear velocity anisotropy beneath Siberia.Acta Seismologica Sinica, Vol. 21, 3, pp. 213-216.RussiaGeophysics - seismics
DS1998-1610
1998
Yang, H.Yang, H., Lyser, K., Ansdell, K.Geochemical and neodymium isotopic compositions of the metasedimentary rocks In the la Ronge DomainPrecambrian Research, Vol. 92, No. 1, Sept. pp. 37-64Saskatchewan, ManitobaTrans Hudson Orogen, Evolution, tectonics
DS200512-0562
2005
Yang, H.Konzett, J., Yang, H., Frost, D.J.Phase relations and stability of magnetoplumbite and crichtonite series phases under upper mantle P-T conditions: an experimental study to 15 GPa with LILEJournal of Petrology, Vol. 46, 4, pp. 749-781.MantleMetasomatism - lithosphere
DS200512-0563
2005
Yang, H.Konzett, J., Yang, H., Frost, D.J.Phase relations and stability of magnetoplumbite and crichtonite series phases under upper mantle P T conditions: an experimental study to 15 GPa. LILEJournal of Petrology, Vol. 46, 4, pp. 749-781.MantleMetasomatism in the lithospheric mantle
DS201801-0064
2017
Yang, H.Simon, S.J., Wei, C.T., Viladkar, S.G., Ellmies, R., Soh, Tamech, L.S., Yang, H., Vatuva, A.Metamitic U rich pyrochlore from Epembe sovitic carbonatite dyke, NW Namibia.Carbonatite-alkaline rocks and associated mineral deposits , Dec. 8-11, abstract p. 12.Africa, Namibiadeposit - Epembe

Abstract: The Epembe carbonatite dyke is located about 80 km north of Opuwo, NW Namibia. The 10 km long dyke is dominated by massive and banded sövitic carbonatite intrusions. Two distinct type of sövite have been recognized: (1) coarse-grained light grey Sövite I which is predominant in brecciated areas and (2) medium- to fine-grained Sövite II which hosts notable concentrations of pyrochlore and apatite. The contact between the carbonatite and basement gneisses is marked by K-feldspar fenite. The pyrochlore chemistry at Epembe shows a compositional trend from primary magmatic Ca-rich pyrochlore toward late hydrothermal fluid enriched carbonatite phase, giving rise to a remarkable shift in chemical composition and invasion of elements such as Si, U, Sr, Ba, Th and Fe. Enrichment in elements like U, Sr and Th lead to metamictization, alteration and A-site vacancy. It is therefore suggested that the carbonatite successive intrusive phases assimilated primary pyrochlore leading to extreme compositional variation especially around the rims of the pyrochlore. The genesis of the Epembe niobium deposit is linked to the carbonatite magmatism but the mechanism that manifested such niobium rich rock remains unclear and might be formed as a result of cumulate process and/or liquid immiscibility of a carbonate-silicate pair.
DS201811-2621
2018
Yang, H.Yang, H., Xiao, J., Yao, Z., Zhang, X., Younus, F., Melnik, R., Wen, B.Homogeneous and heterogenous dislocation nucleation in diamond.Diamond & Related Materials, Vol. 88, pp. 110-117.Mantlediamond morphology

Abstract: Dislocation nucleation plays a key role in plastic deformation of diamond crystal. In this paper, homogeneous and heterogeneous nucleation nature for diamond glide set dislocation and shuffle set dislocation is studied by combining molecular dynamics method and continuum mechanics models. Our results show that although heterogeneous dislocation nucleation can decrease its activation energy, the activation energy at 0?GPa for diamond heterogeneous nucleation is still in the range of 100?eV. For glide set and shuffle set homogeneous nucleation, their critical nucleation shear stress approaches to diamond's ideal shear strength which implies that those dislocations do not nucleate before diamond structural instability only by a purely shearing manner. While for glide set and shuffle set heterogeneous nucleation, their critical nucleation shear stresses are 28.9?GPa and 48.2?GPa, these values are less than diamond's ideal shear strength which implies that these dislocations may be nucleated heterogeneously under certain shear stress condition. In addition, our results also indicate there exists a deformation mode transformation for diamond deformation behavior at strain rate of 10?3/s. Our results provide a new insight into diamond dislocation nucleation and deformation.
DS201906-1317
2019
Yang, H.Liu, J., Wang, W., Yang, H., Wu, Z., Hu, M.Y., Zhao, J., Bi, W., Alp. E.E., Dauphas, N., Liang, W., Chen, B., Lin, J-F.Carbon isotopic signatures of super-deep diamonds mediated by iron redox chemistry.Geochemical Perspectives Letters, Vol. 10, pp. 51-55.Mantleredox

Abstract: Among redox sensitive elements, carbon is particularly important because it may have been a driver rather than a passive recorder of Earth’s redox evolution. The extent to which the isotopic composition of carbon records the redox processes that shaped the Earth is still debated. In particular, the highly reduced deep mantle may be metal-saturated, however, it is still unclear how the presence of metallic phases in?uences the carbon isotopic compositions of super-deep diamonds. Here we report ab initio results for the vibrational properties of carbon in carbonates, diamond, and Fe3C under pressure and temperature conditions relevant to super-deep diamond formation. Previous work on this question neglected the effect of pressure on the equilibrium carbon isotopic fractionation between diamond and Fe3C but our calculations show that this assumption overestimates the fractionation by a factor of ~1.3. Our calculated probability density functions for the carbon isotopic compositions of super-deep diamonds derived from metallic melt can readily explain the very light carbon isotopic compo- sitions observed in some super-deep diamonds. Our results therefore support the view that metallic phases are present during the formation of super-deep diamonds in the mantle below ~250 km.
DS201907-1582
2019
Yang, H.Wang, W., Liu, J., Dauphas, N., Yang, H., Wu, Z., Chen, B., Lin, J-F.Carbon isotopic signatures of diamond formation mediated by iron redox chemistry.Acta Geologica Sinica, Vol. 93, 1, p. 174.Mantleredox

Abstract: Diamonds are key messenger from the deep Earth because someare sourced from the longest isolated and deepest accessible regions of the Earth’s mantle. They are prime recorders of the carbon isotopic compositionof the Earth. The C isotope composition (d13C) of natural diamonds showsa widevariationfrom -41‰ to +3‰ with the primary mode at -5 ± 3‰ [1]. In comparison, the d13C values of chondrites and other planetary bodies range between -26‰ and -15‰ [2]. It is possible that some of the low d13C values were inherited from the Earth’s building blocks,but this is unlikely to be the sole explanation for all low d13C values that can reach as low as -41‰. Organic matter at the Earth’s surface that has low d13C values[3] has been regarded as a possible origin for low d13C values. However, organic carbon is usually accompanied by carbonate with higher d13C values (~0 ‰),and it is not clear why this d13C value does not appear frequently in diamonds. Low d13C diamonds were also formed by deposition from C-O-H fluids,but the equilibrium fractionationinvolved between diamonds and fluids issmall at mantle temperatures [1] and the low d13C values of diamonds can only be achieved after extensive Rayleigh distillation. One unique feature of the Earth isactive plate tectonics driven by mantle convection. Relatively oxidized iron and carbon species at the surface, such as carbonate, Fe2+-and Fe3+-bearing silicatesand oxides, are transported to the deep mantle by subducted slabs and strongly involved inthe redox reactions that generatediamonds [4]. The extent to which the isotopic compositionof C duringdiamond formation recordsredox processes that shaped the Earth is still controversial. Here we report onvibration properties of C andFe at high pressure in carbonates, diamond and Fe3C,based on nuclear resonant inelastic X-ray scattering measurements and density functional theory calculationsand further calculate equilibrium C isotope fractionations among these C-bearing species. Our results demonstrate that redox reactions in subducted slabs could generate eclogitic diamonds with d13C values as low as -41‰ if C in diamonds was sourced from the oxidation of a Fe-C liquid. The large C isotopic fractionation and potentially fast separation between diamonds and a Fe-C melt could enable diamond formation as high as 2%with d13C lower than -40‰.
DS202104-0614
2021
Yang, H.Wang, W.,Liu, J., Yang, H., Dorfman, S.M., Lv, M., Li, J., Zhao, J., Hu, M.Y., bi, W., Alp, E.E., Xiao, Y., Wu, Z., Lin, J-F.Iron force constants of bridgmanite at high pressure: implications for iron isotope fractionation in the deep mantle.Geochimica et Cosmochimica Acta, Vol. 294, pp. 215-231. pdfMantlebridgmanite

Abstract: The isotopic compositions of iron in major mantle minerals may record chemical exchange between deep-Earth reservoirs as a result of early differentiation and ongoing plate tectonics processes. Bridgmanite (Bdg), the most abundant mineral in the Earth’s lower mantle, can incorporate not only Al but also Fe with different oxidation states and spin states, which in turn can influence the distribution of Fe isotopes between Bdg and ferropericlase (Fp) and between the lower mantle and the core. In this study, we combined first-principles calculations with high-pressure nuclear resonant inelastic X-ray scattering measurements to evaluate the effects of Fe site occupancy, valence, and spin states at lower-mantle conditions on the reduced Fe partition function ratio (?-factor) of Bdg. Our results show that the spin transition of octahedral-site (B-site) Fe3+ in Bdg under mid-lower-mantle conditions generates a +0.09‰ increase in its ?-factor, which is the most significant effect compared to Fe site occupancy and valence. Fe2+-bearing Bdg varieties have smaller ?-factors relative to Fe3+-bearing varieties, especially those containing B-site Fe3+. Our models suggest that Fe isotopic fractionation between Bdg and Fp is only significant in the lowermost mantle due to the occurrence of low-spin Fe2+ in Fp. Assuming early segregation of an iron core from a deep magma ocean, we find that neither core formation nor magma ocean crystallization would have resulted in resolvable Fe isotope fractionation. In contrast, Fe isotopic fractionation between low-spin Fe3+-bearing Bdg/Fe2+-bearing Fp and metallic iron at the core-mantle boundary may have enriched the lowermost mantle in heavy Fe isotopes by up to +0.20‰.
DS200612-1562
2006
Yang, H-Y.Yang, J., Wu, C., Zhang, J., Shi, R., meng, F.,Wooden, J., Yang, H-Y.Protolith of eclogites in the north Qaidam and Altun UHP terrane, NW China: earlier oceanic crust?Journal of Asian Earth Sciences, In press, availableChinaUHP, subduction, eclogites
DS1996-1576
1996
Yang, J.Yang, J.Study on the mineralogy and petrology of kimberlite from Yingxian County, Shanxi Province.International Geological Congress 30th Session Beijing, Abstracts, Vol. 2, p. 397.ChinaMineralogy, Deposit - Yingxian County
DS2001-0073
2001
Yang, J.Bai, W., Yang, J., Fang, Yan, ZhangExplosion of ultrahigh pressure minerals in the mantleActa Geologica Sinica, Vol. 22, No. 5, pp. 385-90.MantleUHP
DS2001-1278
2001
Yang, J.Yang, J., Xu, Z., Zhang, J., Chu, C.Y., Zhang, R., LiouTectonic significance of early Paleozoic high pressure rocks in Altun Qaidam Qilian Mountains, northwest.Geological Society of America Memoir, No. 194, pp. 151-70.China, northwestTectonics, ultra high pressure metamorphism
DS2001-1303
2001
Yang, J.Zhang, J., Zhang, Z., Xu, Z., Yang, J., Cui. J.Petrology and geochronology of eclogites from the western segment of the Altyn Tagh, northwestern China.Lithos, Vol. 56, No. 2-3, Mar.pp. 187-206.ChinaGeochronology, Eclogites
DS2003-1313
2003
Yang, J.Song, S., Yang, J., Liou, J.G., Wu, C., Shi, R., Xu, Z.Petrology, geochemistry and isotopic ages of eclogites from the Dulan UHPM terraneLithos, Vol. 70, 3-4, pp. 195-211.ChinaUHP, geochronology
DS2003-1516
2003
Yang, J.Yang, J.Two ultrahigh pressure metamorphic events recognized in the central orogenic belt ofGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.226.ChinaUHP, geochronology
DS200412-1878
2003
Yang, J.Song, S., Yang, J., Liou, J.G., Wu, C., Shi, R., Xu, Z.Petrology, geochemistry and isotopic ages of eclogites from the Dulan UHPM terrane, the North Qaidam NW China.Lithos, Vol. 70, 3-4, pp. 195-211.ChinaUHP, geochronology
DS200412-2168
2003
Yang, J.Yang, J.Two ultrahigh pressure metamorphic events recognized in the central orogenic belt of China: evidence from the U Pb dating of coeGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.226.ChinaUHP, geochronology
DS200412-2169
2003
Yang, J.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
DS200512-1210
2004
Yang, J.Xu, Z., Jiang, M., Yang, J.Mantle structure of Qinghai Tibet Plateau: mantle plume, mantle shear zone and delamination of lithospheric slab.Earth Science Frontiers, Vol. 11, 4, pp. 329-344. Ingenta 1045384775China, TibetSubduction
DS200612-0071
2006
Yang, J.Bai, W., Ren, Y., Yang, J., Fang, Q., Yan, B.The native iron and wustite assemblage: records of oxygen element from the mantle.Acta Geologica Sinica , Vol. 27, 1, pp. 43-50.MantleMineral chemistry
DS200612-1561
2006
Yang, J.Xu, Z., Zeng, L., Liu, F., Yang, J., Zhang, Z., McWilliams, M., Liou, J.G.Polyphase subduction and exhumation of the Sulu high pressure ultrahigh pressure metamorphic terrane.Geological Society of America, Special Paper, No. 403, pp. 93-114.ChinaSubduction UHP
DS200612-1562
2006
Yang, J.Yang, J., Wu, C., Zhang, J., Shi, R., meng, F.,Wooden, J., Yang, H-Y.Protolith of eclogites in the north Qaidam and Altun UHP terrane, NW China: earlier oceanic crust?Journal of Asian Earth Sciences, In press, availableChinaUHP, subduction, eclogites
DS200612-1603
2006
Yang, J.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
DS200712-0491
2007
Yang, J.Jiang, N., Liu, Y., Zhou, W., Yang, J., Zhang, S.Derivation of Mesozoic adakitic magmas from ancient lower crust in the North Chin a craton.Geochimica et Cosmochimica Acta, Vol. 71, 10, May 15, pp. 2591-2608.ChinaSubduction
DS200912-0177
2008
Yang, J.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
DS200912-0827
2008
Yang, J.Xu, S., Wu, W., Xiao, W., Yang, J., Chen, J., Ji, S., Liu, Y.Moissanite in serpentine from the Dabie Mountains in China.Mineralogical Magazine, Vol. 72, 4, pp. 899-908.ChinaUHP
DS200912-0832
2009
Yang, J.Yang, J.Diamonds in ophiolitic mantle rocks and podiform chromitites an unsolved mystery.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyMantleDiamond genesis
DS201012-0871
2010
Yang, J.Yang, J., Cawood, P.A., Du, Y.Detrital record of mountain building: provenance of Jurassic foreland basin to the Dabie Mountains.Tectonics, Vol. 29, 4, TC4011.ChinaUHP
DS201012-0872
2010
Yang, J.Yang, J., Zhang, Z., Xu, X., Li, Y., Li, J., Jia, Y., Liu, Z., Ba, D.Diamond in the Purang peridotite Massif, west of the Yarlung Zangbu Suture, Tibet: a new discovery.Goldschmidt 2010 abstracts, abstractAsia, TibetPurang Massif
DS201112-1131
2011
Yang, J.Yang, J., Xu, X., Li, Y., Liu, Z., Li, J., Ba, D., Robinson, P.T.Diamond discovered from six different ultramafic massifs along the Yarlung Zangbu suture between the Indian and Eurasian plates.Geological Society of America, Annual Meeting, Minneapolis, Oct. 9-12, abstractAsia, IndiaMantle harzburgites
DS201212-0801
2012
Yang, J.Yang, J., Wirth, R., Xu, X., Robinson, P.T., Rong, H.Mineral inclusions in diamonds from ophiolitic peridotite and chromites.GSA Annual Meeting, Paper no. 74-4, abstractChina, TibetDiamond inclusions
DS201312-0979
2013
Yang, J.Wirth, R., Yang, J.Sources of diamond formation revealed by nano-inclusions in diamond.GAC-MAC 2013 SS4: Diamond: from birth in the mantle to emplacement in kimberlite, abstract onlyMantleDiamond inclusions
DS201312-0990
2012
Yang, J.Yang, J., Wirth, R., Xianhzhen, X., Robinson, P.T., Rong, H.Mineral inclusions in diamonds from ophiolitic peridotite and chromities.Geological Society of America Annual Meeting abstract, Paper 74-4, 1/2p. AbstractTechnologyDiamond inclusions
DS201312-0991
2013
Yang, J.Yang, J., Xu, X., Robinson, P.T.Ophiolite type diamond.Geological Society of America Annual Meeting, Vol. 45, 7, p. 451 abstractTechnologyDiamond genesis
DS201412-0547
2014
Yang, J.Mao, Z., Lin, J-F., Yang, J., Bian, H., Liu, J., Watson, H.C., Huang, S., Chen, J., Prakapenka, V.B., Xiao, Y., Chow, P.Fe, Al bearing post-perovskite in the Earth's lower mantle.Earth and Planetary Science Letters, Vol. 403, pp. 157-163.MantlePerovskite
DS201412-0998
2014
Yang, J.Yang, J.Diamonds and highly reduced minerals in ophiolitic mantle rocks and chromitites.ima2014.co.za, AbstractMantleDiamond mineralogy
DS201412-0999
2014
Yang, J.Yang, J., Meng, F., Xu, X., Robinson, P.T., Dilek, Y., Makeyev, A.B., Wirth, R., Wiedenbeck, M., Cliff, J.Diamonds, native elements and metal alloys from chromitites of the Ray-Iz ophiolite of the Polar Urals.Gondwana Research, Vol. 27, 2, pp. 459-485.Asia, TibetUHP ophiolite diamonds
DS201502-0126
2014
Yang, J.Yang, J., Meng, F., Xu, X., Robinson, P.T., Dilek, Y., Makeyev, A.B., Wirth, R., Wiedenbeck, M., Cliff, J.Diamonds, native elements and metal alloys from chromitites of the Ray-Iz ophiolite of the Polar Urals.Gondwana Research, Vol. 27, 2, pp. 459-485.Russia, UralsChromitite
DS201506-0297
2015
Yang, J.Tian, Y., Yang, J., Robinson, P.T., Xiong, F., Li, Y., Zhang, Z., Liu, Z., Liu, F., Niu, X.Diamond discovered in high Al chromitites of the Sartohay ophiolite, Xinjiang province China.Acta Geologica Sinica, Vol. 89, 2, pp. 332-340.ChinaChromitite
DS201506-0302
2015
Yang, J.Zhu, H., Yang, J., Robinson, P.T., Zhu, Y., Zhu, F., Zhao, X., Liu, Z., Zhang, W., Xu, W.The discovery of diamonds in chromitites of the Hegenshan ophiolite, Inner Mongolia, China.Acta Geologica Sinica, Vol. 89, 2, pp. 341-350.China, MongoliaChromitite
DS201512-1994
2015
Yang, J.Yang, J., Dilek, Y., Robinson, P.T.Diamond and recycled mantle: a new perspectve - introduction of IGCP 649 project. OphiolitesActa Geologica Sinica, Vol. 89, 3, pp. 1036-1038.MantleDiamond genesis
DS201601-0019
2015
Yang, J.Huang, Yang, J., Zhu, Y., Xiong, F., Liu, Z., Zhang, Z., Xu, W.The discovery of diamonds in chromitite of the Hegenshan ophiolite, Inner Mongolia.Acta Geologica Sinica, Vol. 89, 2, p. 32.Asia, MongoliaOphiolite

Abstract: Diamond, moissanite and a variety of other minerals, similar to those reported from ophiolites in Tibet and northern Russia, have recently been discovered in chromitites of the Hegenshan ophiolite of the Central Asian Orogenic Belt, north China. The chromitites are small, podiform and vein-like bodies hosted in dunite, clinopyroxene-bearing peridotite, troctolite and gabbro. All of the analysed chromite grains are relatively Al-rich, with Cr# [100Cr/(Cr+Al)] of about 47-53. Preliminary studies of mainly disseminated chromitite from ore body No. 3756 have identified more than 30 mineral species in addition to diamond and moissanite. These include oxides (mostly hematite, magnetite, rutile, anatase, cassiterite, and quartz), sulfides (pyrite, marcasite and others), silicates (magnesian olivine, enstatite, augite, diopside, uvarovite, pyrope, orthoclase, zircon, sphene, vesuvianite, chlorite and serpentine) and others (e.g., calcite, monazite, glauberite, iowaite and a range of metallic alloys). This study demonstrates that diamond, moissanite and other exotic minerals can occur in high-Al, as well as high-Cr chromites, and significantly extends the geographic and age range of known diamond-bearing ophiolites.
DS201601-0050
2015
Yang, J.Yang, J., Wirth, R., Xiong, F., Tian, Y., Huang, Z., Robinson, P.T., Dilek, Y.The lower mantle minerals in ophiolite hosted diamond.Acta Geologica Sinica, Vol. 89, 2, pp. 108-109.MantleMineralogy
DS201603-0395
2015
Yang, J.Lian, D., Yang, J., Dilek, Y., Robinson, P.T., Wu, W., Wang, Y., Liu, F., Ding, Yi.Diamonds and moissanite from the aladag ophiolite of the eastern Tauride belt, southern Turkey: a final report.Geological Society of America Annual Meeting, Vol. 47, 7, p. 163. abstractEurope, TurkeyMoissanite

Abstract: The Aladag ophiolite in the eastern Tauride belt, southern Turkey, is a well-preserved remnant of oceanic lithosphere. It consists of, in ascending order, harzburgitic to dunitic tectonites, ultramafic and mafic cumulates, isotropic gabbros, sheeted dikes and basaltic pillow lavas. Podiform chromitites are common in the mantle peridotites. Thus far, more than 200 grains of microdiamond and more than 100 grains of moissanite (SiC) have been separated from one sample of podiform chromitite. The microdiamonds occur mostly as subhedral to euhedral, colorless to pale yellow grains, about 50-300 ?m in size. Moissanite grains are generally subhedral, light blue to deep blue in color and variable in size. These grains of diamond and moissanite are very similar to in-situ grains in podiform chromitites of Tibet and the Polar Urals of Russia (Yang et al., 2014; 2015), indicating that they are natural minerals, not the result of natural or anthropogenic contamination. As reported elsewhere, the diamonds and moissanite are accompanied by a range of other minerals, including rutile, zircon, quartz and sulfides. The discovery of diamond, moissanite and other unusual minerals in the podiform chromitites of the Aladag massif provide additional evidence for the widespread occurrence of these minerals in ophiolites, indicating that they are related to global mantle processes.
DS201605-0922
2016
Yang, J.Xiong, F., Yang, J., Robinson, P.T., Xu, X., Ba, D., Li, Y., Zhang, Z., Rong, H.Diamonds ad other exotic minerals recovered from peridotites of the Dangqiong ophiolite, western Yarlung-Zangbo suture zone, Tibet.Acta Geologica Sinica, Vol. 90, 2, pp. 425-439.Asia, TibetPeridotite

Abstract: Various combinations of diamond, moissanite, zircon, quartz, corundum, rutile, titanite, almandine garnet, kyanite, and andalusite have been recovered from the Dangqiong peridotites. More than 80 grains of diamond have been recovered, most of which are pale yellow to reddish-orange to colorless. The grains are all 100-200 µm in size and mostly anhedral, but with a range of morphologies including elongated, octahedral and subhedral varieties. Their identification was confirmed by a characteristic shift in the Raman spectra between 1325 cm?1 and 1333 cm?1, mostly at 1331.51 cm?1 or 1326.96 cm?1. Integration of the mineralogical, petrological and geochemical data for the Dongqiong peridotites suggests a multi-stage formation for this body and similar ophiolites in the Yarlung-Zangbo suture zone. Chromian spinel grains and perhaps small bodies of chromitite crystallized at various depths in the upper mantle, and encapsulated the UHP, highly reduced and crustal minerals. Some oceanic crustal slabs containing the chromian spinel and their inclusion were later trapped in suprasubduction zones (SSZ), where they were modified by island arc tholeiitic and boninitic magmas, thus changing the chromian spinel compositions and depositing chromitite ores in melt channels.
DS201606-1093
2015
Yang, J.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.
DS201607-1387
2016
Yang, J.Yang, J., Dilek, Y., Pearce, J., Schertl, H-P., Zhang, C.Diamonds and crustal recycling into deep mantle.IGC 35th., Session The Deep Earth 1 p. abstractMantleSubduction
DS201612-2349
2016
Yang, J.Yang, J., Robinson, P.T., Dilek, Y.Geological occurrences of diamond-bearing ophiolites.Acta Geologica Sinica, Vol. 90, 1, July abstract P. 216GlobalUHP
DS201709-2076
2017
Yang, J.Xiong, F., Yang, J., Robinson, P.T., Dilek, Y., Milushi, I., Xu, X., Zhou, W., Zhang, Z., Rong, H.Diamonds discovered from high-Cr podiform chromitites from Bulqiza, eastern Mirdita ophiolite, Albania.Acta Geologica Sinica, Vol. 91, 2, pp. 455-468.Europe, Albaniadiamonds in chromitites

Abstract: Various combinations of diamond, moissanite, zircon, corundum, rutile and titanitehave been recovered from the Bulqiza chromitites. More than 10 grains of diamond have been recovered, most of which are pale yellow to reddish–orange to colorless. The grains are all 100–300 ?m in size and mostly anhedral, but with a range of morphologies including elongated, octahedral and subhedral varieties. Their identification was confirmed by a characteristic shift in the Raman spectra between 1325 cm?1 and 1333 cm?1, mostly at 1331.51 cm?1 or 1326.96 cm?1. This investigation extends the occurrence of diamond and moissanite to the Bulqiza chromitites in the Eastern Mirdita Ophiolite. Integration of the mineralogical, petrological and geochemical data of the Bulqiza chromitites suggests their multi–stage formation. Magnesiochromite grains and perhaps small bodies of chromitite formed at various depths in the upper mantle, and encapsulated the ultra–high pressure, highly reduced and crustal minerals. Some oceanic crustal slabs containing the magnesiochromite and their inclusion were later trapped in suprasubduction zones, where they were modified by tholeiitic and boninitic arc magmas, thus changing the magnesiochromite compositions and depositing chromitite ores in melt channels.
DS201710-2240
2017
Yang, J.Lian, D., Yang, J., Dilek, Y., Wu, W., Zhang, Z., Xiong, F., Liu, F., Zhou, W.Deep mantle origin and ultra-reducing conditions in podiform chromitite: diamonds, moissanite, and other unusual minerals in podiform chromitites from the Pozanti-Karsanti ophiolite, southern Turkey.Americam Mineralogist, Vol. 103, 5p.Europe, Turkeymoissanites

Abstract: The Pozanti-Karsanti ophiolite situated in the eastern Tauride belt, southern Turkey, is a well-preserved oceanic lithosphere remnant comprising, in ascending order, mantle peridotite, ultramafic and mafic cumulates, isotropic gabbros, sheeted dikes, and basaltic pillow lavas. Two types of chromitites are observed in the Pozanti-Karsanti ophiolite. One type of chromitites occurs in the cumulate dunites around the Moho, and the other type of chromitites is hosted by the mantle harzburgites below the Moho. The second type of chromitites has massive, nodular, and disseminated textures. We have conducted the mineral separation work on the podiform chromitites hosted by harzburgites. So far, more than 100 grains of microdiamond and moissanite (SiC) have been recovered from the podiform chromitite. The diamonds and moissanite are accompanied by large amounts of rutile. Besides zircon, monazite and sulfide are also very common phases within the separated minerals. The discovery of diamond, moissanite, and the other unusual minerals from podiform chromitite of the Pozanti-Karsanti ophiolite provides new evidences for the common occurrences of these unusual minerals in ophiolitic peridotites and chromitites. This discovery also suggests that deep mantle processes and materials have been involved in the formation of podiform chromitite.
DS201710-2262
2017
Yang, J.Robinson, P.T., Yang, J., Tian, Y., Zhu, H.Diamonds, super reduced and crustal minerals in chromitites of the Hegenshan and Sartohay ophiolites, central Asian orogenic belt, China.Acta Geologica Sinica, Vol. 91, s1, p. 32 abstractChinadiamond inclusions

Abstract: The Central Asian Orogenic Belt (CAOB) is a huge tectonic mélange that lies between the North China Craton and the Siberian Block. It is composed of multiple orogenic belts, continental fragments, magmatic and metamorphic rocks, suture zones and discontinuous ophiolite belts. Although the Hegenshan and Sartohay ophiolites are separated by nearly 3000 km and lie in completely different parts of the CAOB, they are remarkably similar in many respects. Both are composed mainly of serpentinized peridotite and dunite, with minor gabbro and sparse basalt. They both host significant podiform chromitites that consist of high-Al, refractory magnesiochromite with Cr#s [100Cr/(Cr+Al)] averaging >60. The Sartohay ophiolite has a zircon U-Pb age of ca. 300 Ma and has been intruded by granitic plutons of similar age, resulting in intense hydrothermal activity and the formation of gold-bearing listwanites. The age of the Hegenshan is not firmly established but is thought to have formed in the Carboniferous. Like many other ophiolites that we have investigated in other orogenic belts, the chromitites in these two bodies have abundant diamonds, as well as numerous super-reduced and crustal minerals. The diamonds are mostly, colorless to pale yellow, 200-300 ?m across and have euhedral to anhedral shapes. They all have low carbon isotopes (?14C = ?18 to ?29) and some have visible inclusions. These are accompanied by numerous super-reduced minerals such as moissanite, native elements (Fe, Cr, Si, Al, Mn), and alloys (e.g., Ni-Mn-Fe, Ni-Fe-Al, Ni-Mn-Co, Cr-Ni-Fe, Cr-Fe, Cr-Fe-Mn), as well as a wide range of oxides, sulfides and silicates. Grains of zircon are abundant in the chromitites of both ophiolites and range in age from Precambrian to Cretaceous, reflecting both incorporation of old zircons and modification of grains by hydrothermal alteration. Our investigation confirms that high-Al, refractory chromitites in these two ophiolites have the same range of exotic minerals as high-Cr metallurgical chromitites such as those in the Luobusa ophiolite of Tibet. These collections of exotic minerals in ophiolitic chromitites indicate complex, multi-stage recycling of oceanic and continental crustal material at least to the mantle transition zone, followed by uprise and emplacement of the peridotites into relatively shallow ophiolites.
DS201710-2279
2017
Yang, J.Wu, W., Yang, J., Ma, C., Milushi, I., Lian, D., Tian, Y.Discovery and significance of diamonds and moissanites in chromitites within the Skenderbeu Massif of the Mirdita zone ophiolite, west Albania.Acta Geologica Sinica, Vol. 91, 3, pp. 882-897.Europe, Albaniamoissanites

Abstract: In recent years diamonds and other unusual minerals (carbides, nitrides, metal alloys and native elements) have been recovered from mantle peridotites and chromitites (both high-Cr chromitites and high-Al chromitites) from a number of ophiolites of different ages and tectonic settings. Here we report a similar assemblage of minerals from the Skenderbeu massif of the Mirdita zone ophiolite, west Albania. So far, more than 20 grains of microdiamonds and 30 grains of moissanites (SiC) have been separated from the podiform chromitite. The diamonds are mostly light yellow, transparent, euhedral crystals, 200-300 ?m across, with a range of morphologies; some are octahedral and cuboctahedron and others are elongate and irregular. Secondary electron images show that some grains have well-developed striations. All the diamond grains have been analyzed and yielded typical Raman spectra with a shift at ?1325 cm?1. The moissanite grains recovered from the Skenderbeu chromitites are mainly light blue to dark blue, but some are yellow to light yellow. All the analyzed grains have typical Raman spectra with shifts at 766 cm?1, 787 cm?1, and 967 cm?1. The energy spectrums of the moissanites confirm that the grains are composed entirely of silicon and carbon. This investigation expands the occurrence of diamonds and moissanites to Mesozoic ophiolites in the Neo-Tethys. Our new findings suggest that diamonds and moissanites are present, and probably ubiquitous in the oceanic mantle and can provide new perspectives and avenues for research on the origin of ophiolites and podiform chromitites.
DS201711-2537
2017
Yang, J.Zhu, R., Zhang, H., Zhu, G., Meng, H., Fan, H., Yang, J., Wu, F., Zhang, Z.Craton destruction and related resources.International Journal of Earth Sciences, Vol. 106, 7, pp. 2233-2257.Chinacraton

Abstract: Craton destruction is a dynamic event that plays an important role in Earth’s evolution. Based on comprehensive observations of many studies on the North China Craton (NCC) and correlations with the evolution histories of other cratons around the world, craton destruction has be defined as a geological process that results in the total loss of craton stability due to changes in the physical and chemical properties of the involved craton. The mechanisms responsible for craton destruction would be as the follows: (1) oceanic plate subduction; (2) rollback and retreat of a subducting oceanic plate; (3) stagnation and dehydration of a subducting plate in the mantle transition zone; (4) melting of the mantle above the mantle transition zone caused by dehydration of a stagnant slab; (5) non-steady flow in the upper mantle induced by melting, and/or (6) changes in the nature of the lithospheric mantle and consequent craton destruction caused by non-steady flow. Oceanic plate subduction itself does not result in craton destruction. For the NCC, it is documented that westward subduction of the paleo-Pacific plate should have initiated at the transition from the Middle-to-Late Jurassic, and resulted in the change of tectonic regime of eastern China. We propose that subduction, rollback and retreat of oceanic plates and dehydration of stagnant slabs are the main dynamic factors responsible for both craton destruction and concentration of mineral deposits, such as gold, in the overriding continental plate. Based on global distribution of gold deposits, we suggest that convergent plate margins are the most important setting for large gold concentrations. Therefore, decratonic gold deposits appear to occur preferentially in regions with oceanic subduction and overlying continental lithospheric destruction/modification/growth.
DS201802-0261
2017
Yang, J.Robinson, P.T., Yang, J., Tian, Y., Zhu, H.Diamonds, super reduced and crustal minerals in chromitites of the Hegenshan and Sartohay ophiolites, central Asian orogenic belt, China.Acta Geologica Sinica, Vol. 91, 1, p. 32.Asia, Chinamineralogy

Abstract: The Central Asian Orogenic Belt (CAOB) is a huge tectonic mélange that lies between the North China Craton and the Siberian Block. It is composed of multiple orogenic belts, continental fragments, magmatic and metamorphic rocks, suture zones and discontinuous ophiolite belts. Although the Hegenshan and Sartohay ophiolites are separated by nearly 3000 km and lie in completely different parts of the CAOB, they are remarkably similar in many respects. Both are composed mainly of serpentinized peridotite and dunite, with minor gabbro and sparse basalt. They both host significant podiform chromitites that consist of high-Al, refractory magnesiochromite with Cr#s [100Cr/(Cr+Al)] averaging >60. The Sartohay ophiolite has a zircon U-Pb age of ca. 300 Ma and has been intruded by granitic plutons of similar age, resulting in intense hydrothermal activity and the formation of gold-bearing listwanites. The age of the Hegenshan is not firmly established but is thought to have formed in the Carboniferous.Like many other ophiolites that we have investigated in other orogenic belts, the chromitites in these two bodies have abundant diamonds, as well as numerous super-reduced and crustal minerals. The diamonds are mostly, colorless to pale yellow, 200-300 ?m across and have euhedral to anhedral shapes. They all have low carbon isotopes (?14C = ?18 to ?29) and some have visible inclusions. These are accompanied by numerous super-reduced minerals such as moissanite, native elements (Fe, Cr, Si, Al, Mn), and alloys (e.g., Ni-Mn-Fe, Ni-Fe-Al, Ni-Mn-Co, Cr-Ni-Fe, Cr-Fe, Cr-Fe-Mn), as well as a wide range of oxides, sulfides and silicates. Grains of zircon are abundant in the chromitites of both ophiolites and range in age from Precambrian to Cretaceous, reflecting both incorporation of old zircons and modification of grains by hydrothermal alteration. Our investigation confirms that high-Al, refractory chromitites in these two ophiolites have the same range of exotic minerals as high-Cr metallurgical chromitites such as those in the Luobusa ophiolite of Tibet. These collections of exotic minerals in ophiolitic chromitites indicate complex, multi-stage recycling of oceanic and continental crustal material at least to the mantle transition zone, followed by uprise and emplacement of the peridotites into relatively shallow ophiolites.
DS201804-0685
2018
Yang, J.Dilek, Y., Yang, J.Ophiolites, diamonds, and ultrahigh pressure minerals: new discoveries and concepts on upper mantle petrogenesis.Lithosphere, Vol. 10, 1, pp. 3-13.MantleUHP - metasomatism

Abstract: Ophiolitic peridotites represent variously depleted residues of the primitive mantle after multiple episodes of partial melting, melt extraction, and melt-rock interactions. They display a wide range of compositional and geochemical heterogeneities at different scales, and their incompatible bulk-rock compositions and mineral chemistries are commonly inconsistent with their evolution through simple partial melting processes at shallow mantle depths. Approaching these issues from different perspectives, the papers in this volume concentrate on (1) melt evolution and magmatic construction of ophiolites in various tectonic settings, and (2) the occurrence of microdiamonds, ultrahigh-pressure (UHP) minerals, and crustal material as inclusions in ophiolitic chromitites and peridotites. Crustal and mantle rock units exposed in different ophiolites show that the mantle melt sources of ophiolitic magmas undergo progressive melting, depletion, and enrichment events, constantly modifying the melt compositions and the mineralogical and chemical makeup of residual peridotites. Formation and incorporation of microdiamonds and UHP minerals into chromite grains occurs at depths of 350-660 km in highly reducing conditions of the mantle transition zone. Carbon for microdiamonds and crustal minerals are derived from subduction-driven recycling of surface material. Host peridotites with their UHP mineral and diamond inclusions are transported into shallow mantle depths by asthenospheric upwelling, associated with either slab rollback-induced channel flow or superplumes. Decompression melting of transported mantle rocks beneath oceanic spreading centers and their subsequent flux melting in mantle wedges result in late-stage formation of podiform chromitites during the upper mantle petrogenesis of ophiolites. Future studies should demonstrate whether diamonds and UHP minerals also occur in peridotites and chromitites of nonsubduction-related ophiolites.
DS201805-0993
2018
Yang, J.Xiong, F., Yang, J., Xu, X., Kapsiotis, A., Hao, X., Liu, Z.Compositional and isotopic heterogeneities in the Neo-Tethyan upper mantle recorded by coexisting Al rich and Cr rich chromitites in the Purang massif, SW Tibet (China).Journal of Asian Earth Sciences, Vol. 159, pp. 109-129.China, Tibetchromitites

Abstract: The Purang harzburgite massif in SW Tibet (China) hosts abundant chrome ore deposits. Ores consist of 20 to >95% modal chromian spinel (Cr-spinel) with mylonitic fabric in imbricate shaped pods. The composition of Cr-spinel in these ores ranges from Al-rich [Cr#Sp or Cr/(Cr?+?Al)?×?100?=?47.60-57.56] to Cr-rich (Cr#Sp: 62.55-79.57). Bulk platinum-group element (PGE) contents of chromitites are also highly variable ranging from 17.5?ppb to ?2.5?ppm. Both metallurgical and refractory chromitites show a general enrichment in the IPGE (Os, Ir and Ru) with respect to the PPGE (Rh, Pt and Pd), resulting mostly in right-sloping primitive mantle (PM)-normalized PGE profiles. The platinum-group mineral (PGM) assemblages of both chromitite types are dominated by heterogeneously distributed, euhedral Os-bearing laurite inclusions in Cr-spinel. The Purang chromitites have quite inhomogeneous 187Os/188Os ratios (0.12289-0.13194) that are within the range of those reported for mantle-hosted chromitites from other peridotite massifs. Geochemical calculations demonstrate that the parental melts of high-Cr chromitites were boninitic, whereas those of high-Al chromitites had an arc-type tholeiitic affinity. Chromite crystallization was most likely stimulated by changes in magma compositions due to melt-peridotite interaction, leading to the establishment of a heterogeneous physicochemical environment during the early crystallization of the PGM. The highly variable PGE contents, inhomogeneous Os-isotopic compositions and varying Cr#Sp ratios of these chromitites imply a polygenetic origin for them from spatially distinct melt inputs. The generally low ?Os values (<1) of chromitites indicate that their parental melts originated within different sections of a heterogeneously depleted mantle source region. These melts were most likely produced in the mantle wedge above a downgoing lithospheric slab.
DS201807-1538
2015
Yang, J.Yang, J., Robinson, P.T., Dilek, Y.Diamond bearing ophiolites and their geological occurrence. ** note dateEpisodes, Vol. 38, 4, pp. 344-364.China, Tibet, Russiaophiolites

Abstract: We document in this study the geological occurrence of diamonds and other ultrahigh-pressure (UHP) minerals in ophiolitic mantle peridotites and podiform chromitites from different orogenic belts. These minerals exist in both high-Cr and high-Al chromitites. Most ophiolite-hosted diamonds are small (? 200-500 ?m across), and some contain distinctive inclusions (i.e., coesite, Ni-Mn-Co alloys, spessartite, tephroite). All of the analyzed diamonds have extremely light carbon isotope compositions (?13C = -28.7 to -18.3‰) and variable trace element contents that distinguish them from most kimberlitic and UHP metamorphic varieties. A wide range of highly reduced minerals, such as native elements, Ni-Mn-Co alloys, Fe-Si and Fe-C phases and moissanite (SiC) also occuras accompanying mineral separates confirming the super-reducing conditions of their environment of formation. The presence of exsolution lamellae of diopside and coesite in some chromite grains suggests chromite crystallization depths around >380 km, near the mantle transition zone. Carbon and other recycled crustal materials at these depths are likely to have been derived from previously subducted material. The peridotites encapsulating the podiform chromitites and diamonds were transported to shallow mantle by convection cells beneath oceanic spreading centers. The chromitites may have formed in the deep mantle or in shallow suprasubduction zone environments. Our observations suggest that diamonds, UHP minerals and recycled crustal material are likely to be ubiquitous in the oceanic mantle.
DS201808-1744
2018
Yang, J.Fu, S., Yang, J., Zhang, Y., Okuschi, T., McCammon, C., Kim, H-I., Lee, S.K., Lin, J-F.Abnormal elasticity of Fe bearing bridgmanite in the Earth's lower mantle.Geophysical Research Letters, Vol. 45, 10, pp. 4725-4732.Mantlebridgmanite

Abstract: Seismic heterogeneities in the Earth's lower mantle have been attributed to thermal and/or chemical variations of constituent minerals. Bridgmanite is the most abundant lower?mantle mineral and contains Fe and Al in its structure. Knowing the effect of Fe on compressional and shear wave velocities (VP, VS) and density of bridgmanite at relevant pressure?temperature conditions can help to understand seismic heterogeneities in the region. However, experimental studies on both VP and VS of Fe?bearing bridgmanite have been limited to pressures below 40 GPa. In this study, VP and VS of Fe?bearing bridgmanite were measured up to 70 GPa in the diamond anvil cell. We observed drastic softening of VP by ~6(±1)% at 42.6-58 GPa and increased VS at pressures above 40 GPa. We interpret these observations as due to a spin transition of Fe3+. These observations are different to previous views on the effect of Fe on seismic velocities of bridgmanite. We propose that the abnormal sound velocities of Fe?bearing bridgmanite could help to explain the seismically observed low correlation between VP and VS in the mid?lower mantle. Our results challenge existing models of Fe enrichment to explain the origin of Large Low Shear Velocity provinces in the lowermost mantle.
DS201809-2010
2018
Yang, J.Chen, Y., Yang, J., Xu, Z., Tian, Y., Shengmin, L.Diamonds and other unusual minerals from peridotites of the Myitkyin a ophiolite, Myanmar.Journal of Asian Earth Sciences, Vol. 164, pp. 179-193.Asia, Myanmarperidotites

Abstract: Peridotites from the Myitkyina ophiolite are mainly composed of lherzolite and harzburgite. The lherzolites have relatively fertile compositions, with 39.40-43.40?wt% MgO, 1.90-3.17?wt% Al2O3 and 1.75-2.84?wt% CaO. They contain spinel and olivine with lower Cr# (12.6-18.2) and Fo values (88.7-91.6) than those of the harzburgites (24.5-59.7 and 89.6-91.6 respectively). The harzburgites have more refractory compositions, containing 42.40-46.23?wt% MgO, 0.50-1.64?wt% Al2O3 and 0.40-1.92?wt% CaO. PGE contents of the peridotites show an affinity to the residual mantle. Evaluation of petrological and geochemical characteristics of these peridotites suggests that the lherzolites and harzburgites represent residual mantle after low to moderate degrees of partial melting, respectively, in the spinel stability field. The U-shaped, primitive mantle-normalized REE patterns and strong positive Ta and Pb anomalies of the harzburgites suggest melt/fluid refertilization in either a MOR or SSZ setting after their formation at a MOR. Mineral separation of the peridotites has yield a range of exotic minerals, including diamond, moissanite, native Si, rutile and zircon, a collection similar to that reported for ophiolites of Tibet and the Polar Urals. The discovery of these exotic minerals in the Myitkyina ophiolite supports the view that they occur widely in the upper oceanic mantle.
DS201809-2057
2018
Yang, J.Lian, D., Yang, J., Wiedenbeck, M., Dilek, Y., Rocholl, A., Wu, W.Carbon and nitrogen isotope, and mineral inclusion studies on the diamonds from the Pozanti-Karsanti chromitite, Turkey. MicrodiamondsContributions to Mineralogy and Petrology, doi.org:10.1007/ s00410-018-1499-5 19p.Europe, Turkeydiamond inclusions

Abstract: The Pozanti-Karsanti ophiolite (PKO) is one of the largest oceanic remnants in the Tauride belt, Turkey. Micro-diamonds were recovered from the podiform chromitites, and these diamonds were investigated based on morphology, color, cathodoluminescence, nitrogen content, carbon and nitrogen isotopes, internal structure and inclusions. The diamonds recovered from the PKO are mainly mixed-habit diamonds with sectors of different brightness under the cathodoluminescence images. The total ?13C range of the PKO diamonds varies between ? 18.8 and ? 28.4‰, with a principle ?13C mode at ? 25‰. Nitrogen contents of the diamonds range from 7 to 541 ppm with a mean value of 171 ppm, and the ?15N values range from ? 19.1 to 16.6‰, with a ?15N mode of ? 9‰. Stacking faults and partial dislocations are commonly observed in the Transmission Electron Microscopy foils whereas inclusions are rather rare. Combinations of ( Ca0.81Mn0.19)SiO3, NiMnCo-alloy and nanosized, quenched fluid phases were observed as inclusions in the PKO diamonds. We believe that the 13C-depleted carbon signature of the PKO diamonds derived from previously subducted crustal matter. These diamonds may have crystallized from C-saturated fluids in the asthenospheric mantle at depth below 250 km which were subsequently carried rapidly upward by asthenospheric melts.
DS201901-0046
2018
Yang, J.Lin, J-F, Mao, Z., Yang, J., Fu, F.Elasticity of lower-mantle bridgemanite.Nature, Vol. 564, pp. E18-E26.Mantlebridgmanite
DS201902-0315
2018
Yang, J.Rummel, L., Kaus, B.J.P., White, R.W., Mertz, D.F., Yang, J., Baumann, T.S.Coupled petrological geodynamical modeling of a compositionally heterogeneous mantle plume.Tectonophysics, Vol. 723, pp. 242-260.Mantlehot spot

Abstract: Self-consistent geodynamic modeling that includes melting is challenging as the chemistry of the source rocks continuously changes as a result of melt extraction. Here, we describe a new method to study the interaction between physical and chemical processes in an uprising heterogeneous mantle plume by combining a geodynamic code with a thermodynamic modeling approach for magma generation and evolution. We pre-computed hundreds of phase diagrams, each of them for a different chemical system. After melt is extracted, the phase diagram with the closest bulk rock chemistry to the depleted source rock is updated locally. The petrological evolution of rocks is tracked via evolving chemical compositions of source rocks and extracted melts using twelve oxide compositional parameters. As a result, a wide variety of newly generated magmatic rocks can in principle be produced from mantle rocks with different degrees of depletion. The results show that a variable geothermal gradient, the amount of extracted melt and plume excess temperature affect the magma production and chemistry by influencing decompression melting and the depletion of rocks. Decompression melting is facilitated by a shallower lithosphere-asthenosphere boundary and an increase in the amount of extracted magma is induced by a lower critical melt fraction for melt extraction and/or higher plume temperatures. Increasing critical melt fractions activates the extraction of melts triggered by decompression at a later stage and slows down the depletion process from the metasomatized mantle. Melt compositional trends are used to determine melting related processes by focusing on K2O/Na2O ratio as indicator for the rock type that has been molten. Thus, a step-like-profile in K2O/Na2O might be explained by a transition between melting metasomatized and pyrolitic mantle components reproducible through numerical modeling of a heterogeneous asthenospheric mantle source. A potential application of the developed method is shown for the West Eifel volcanic field.
DS201905-1086
2019
Yang, J.Wu, W., Yang, J., Wirth, R., X=Zheng, J., Lian, D., Qiu, T., Milushi, I.Carbon and nitrogen isotopes and mineral inclusions in diamonds from chromitites of the Mirdita ophiolite ( Albania) demonstrate recycling of oceanic crust into the mantle.American Mineralogist, Vol. 104, pp. 485-500.Europe, Albaniadiamond inclusions

Abstract: Geophysical investigations and laboratory experiments provide strong evidence for subduction of ancient oceanic crust, and geological and mineralogical observations suggest that subducted oceanic crust is recycled into the upper mantle. This model is supported by some direct petrologic and miner-alogical evidence, principally the recovery of super-deep diamonds from kimberlites and the presence of crustal materials in ophiolitic chromitites and peridotites, but many details are still unclear. Here we report the discovery of ophiolite-hosted diamonds in the podiform chromitites of the Skenderbeu massif of the Mirdita ophiolite in the western part of Neo-Tethys. The diamonds are characterized by exceedingly light C isotopes (?13CPDB ~ -25‰), which we interpret as evidence for subduction of organic carbon from Earth's surface. They are also characterized by an exceptionally large range in ? 15Nair (-12.9‰ to +25.5‰), accompanied by a low N aggregation state. Materials sparsely included in diamonds include amorphous material, Ni-Mn-Co alloy, nanocrystals (20 × 20 nm) of calcium silicate with an orthorhombic perovskite structure (Ca-Pv), and fluids. The fluids coexisting with the alloy and Ca-Pv provide clear evidence that the diamonds are natural rather than synthetic. We suggest that the Skenderbeu diamonds nucleated and grew from a C-saturated, NiMnCo-rich melt derived from a subducted slab of ocean crust and lithosphere in the deep mantle, at least in the diamond stability field, perhaps near the top of the mantle transition zone. The subsequent rapid upward transport in channeled networks related to slab rollback during subduction initiation may explain the formation and preservation of Skenderbeu diamonds. The discovery of diamonds from the Mirdita ophiolite not only provides new evidence of diamonds in these settings but also provides a valuable opportunity to understand deep cycling of subducted oceanic crust and mantle composition.
DS201907-1586
2019
Yang, J.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.
DS201907-1587
2019
Yang, J.Yang, J., Robinson, P., Xu, X., Xiong, F., Lian, D.Diamond in oceanic peridotites and chromitites: evidence for deep recycled mantle in the global ophiolite record.Acta Geologica Sinica, Vol. 93, 2, p.42.Europe, Turkey, Albania, Russia, Chinamicrodiamonds

Abstract: Diamonds have been discovered in mantle peridotites and chromitites of six ophiolitic massifs along the 1300 km?long Yarlung?Zangbo suture (Bai et al., 1993; Yang et al., 2014; Xu et al., 2015), and in the Dongqiao and Dingqing mantle peridotites of the Bangong?Nujiang suture in the eastern Tethyan zone (Robinson et al., 2004; Xiong et al., 2018). Recently, in?situ diamond, coesite and other UHP mineral have also been reported in the Nidar ophiolite of the western Yarlung?Zangbo suture (Das et al., 2015, 2017). The above?mentioned diamond?bearing ophiolites represent remnants of the eastern Mesozoic Tethyan oceanic lithosphere. New publications show that diamonds also occur in chromitites in the Pozanti?Karsanti ophiolite of Turkey, and in the Mirdita ophiolite of Albania in the western Tethyan zone (Lian et al., 2017; Xiong et al., 2017; Wu et al., 2018). Similar diamonds and associated minerals have also reported from Paleozoic ophiolitic chromitites of Central Asian Orogenic Belt of China and the Ray?Iz ophiolite in the Polar Urals, Russia (Yang et al., 2015a, b; Tian et al., 2015; Huang et al, 2015). Importantly, in?situ diamonds have been recovered in chromitites of both the Luobusa ophiolite in Tbet and the Ray?Iz ophiolite in Russia (Yang et al., 2014, 2015a). The extensive occurrences of such ultra?high pressure (UHP) minerals in many ophiolites suggest formation by similar geological events in different oceans and orogenic belts of different ages. Compared to diamonds from kimberlites and UHP metamorphic belts, micro?diamonds from ophiolites present a new occurrence of diamond that requires significantly different physical and chemical conditions of formation in Earth's mantle. The forms of chromite and qingsongites (BN) indicate that ophiolitic chromitite may form at depths of >150?380 km or even deeper in the mantle (Yang et al., 2007; Dobrthinetskaya et al., 2009). The very light C isotope composition (?13C ?18 to ?28‰) of these ophiolitic diamonds and their Mn?bearing mineral inclusions, as well as coesite and clinopyroxene lamallae in chromite grains all indicate recycling of ancient continental or oceanic crustal materials into the deep mantle (>300 km) or down to the mantle transition zone via subduction (Yang et al., 2014, 2015a; Robinson et al., 2015; Moe et al., 2018). These new observations and new data strongly suggest that micro?diamonds and their host podiform chromitite may have formed near the transition zone in the deep mantle, and that they were then transported upward into shallow mantle depths by convection processes. The in?situ occurrence of micro?diamonds has been well?demonstrated by different groups of international researchers, along with other UHP minerals in podiform chromitites and ophiolitic peridotites clearly indicate their deep mantle origin and effectively address questions of possible contamination during sample processing and analytical work. The widespread occurrence of ophiolite?hosted diamonds and associated UHP mineral groups suggests that they may be a common feature of in?situ oceanic mantle. The fundamental scientific question to address here is how and where these micro?diamonds and UHP minerals first crystallized, how they were incorporated into ophiolitic chromitites and peridotites and how they were preserved during transport to the surface. Thus, diamonds and UHP minerals in ophiolites have raised new scientific problems and opened a new window for geologists to study recycling from crust to deep mantle and back to the surface.
DS201908-1827
2018
Yang, J.Yang, J., Robinson, P.T., Xu, X., Xiong, F., Lian, D.Diamond in oceanic peridotites and chromitites: evidence for deep recycled mantle in the global ophiolite record.International Symposium on Deep Earth Exploration and Practices, Beijing Oct. 24-26. 1 p. abstractChinadiamond genesis

Abstract: Diamonds have been discovered in mantle peridotites and chromitites of six ophiolitic massifs along the 1300 km?long Yarlung?Zangbo suture (Bai et al., 1993; Yang et al., 2014; Xu et al., 2015), and in the Dongqiao and Dingqing mantle peridotites of the Bangong?Nujiang suture in the eastern Tethyan zone (Robinson et al., 2004; Xiong et al., 2018). Recently, in?situ diamond, coesite and other UHP mineral have also been reported in the Nidar ophiolite of the western Yarlung?Zangbo suture (Das et al., 2015, 2017). The above?mentioned diamond?bearing ophiolites represent remnants of the eastern Mesozoic Tethyan oceanic lithosphere. New publications show that diamonds also occur in chromitites in the Pozanti?Karsanti ophiolite of Turkey, and in the Mirdita ophiolite of Albania in the western Tethyan zone (Lian et al., 2017; Xiong et al., 2017; Wu et al., 2018). Similar diamonds and associated minerals have also reported from Paleozoic ophiolitic chromitites of Central Asian Orogenic Belt of China and the Ray?Iz ophiolite in the Polar Urals, Russia (Yang et al., 2015a, b; Tian et al., 2015; Huang et al, 2015). Importantly, in?situ diamonds have been recovered in chromitites of both the Luobusa ophiolite in Tbet and the Ray?Iz ophiolite in Russia (Yang et al., 2014, 2015a). The extensive occurrences of such ultra?high pressure (UHP) minerals in many ophiolites suggest formation by similar geological events in different oceans and orogenic belts of different ages. Compared to diamonds from kimberlites and UHP metamorphic belts, micro?diamonds from ophiolites present a new occurrence of diamond that requires significantly different physical and chemical conditions of formation in Earth's mantle. The forms of chromite and qingsongites (BN) indicate that ophiolitic chromitite may form at depths of >150?380 km or even deeper in the mantle (Yang et al., 2007; Dobrthinetskaya et al., 2009). The very light C isotope composition (?13C ?18 to ?28‰) of these ophiolitic diamonds and their Mn?bearing mineral inclusions, as well as coesite and clinopyroxene lamallae in chromite grains all indicate recycling of ancient continental or oceanic crustal materials into the deep mantle (>300 km) or down to the mantle transition zone via subduction (Yang et al., 2014, 2015a; Robinson et al., 2015; Moe et al., 2018). These new observations and new data strongly suggest that micro?diamonds and their host podiform chromitite may have formed near the transition zone in the deep mantle, and that they were then transported upward into shallow mantle depths by convection processes. The in?situ occurrence of micro?diamonds has been well?demonstrated by different groups of international researchers, along with other UHP minerals in podiform chromitites and ophiolitic peridotites clearly indicate their deep mantle origin and effectively address questions of possible contamination during sample processing and analytical work. The widespread occurrence of ophiolite?hosted diamonds and associated UHP mineral groups suggests that they may be a common feature of in?situ oceanic mantle. The fundamental scientific question to address here is how and where these micro?diamonds and UHP minerals first crystallized, how they were incorporated into ophiolitic chromitites and peridotites and how they were preserved during transport to the surface. Thus, diamonds and UHP minerals in ophiolites have raised new scientific problems and opened a new window for geologists to study recycling from crust to deep mantle and back to the surface.
DS201909-2066
2019
Yang, J.Niu, X., Dilek, Y., Liu, F., Feng, G., Yang, J.Early Devonian ultrapotassic magmatism in the North China craton: geochemical and isotopic evidence for subcontinental lithospheric mantle metasomatism by subducted sediment - derived fluids.Geological Magazine, 17p. PdfChinametasomatism

Abstract: We report new U-Pb zircon age data, zircon in situ oxygen isotope, mineral chemistry, whole-rock geochemistry and Sr-Nd isotopic compositions from the Early Devonian ultrapotassic Gucheng pluton in the North China Craton, and discuss its petrogenesis. The Gucheng pluton is exposed in the northern part of the North China Craton and forms a composite intrusion, consisting of K-feldspar-bearing clinopyroxenite, clinopyroxene-bearing syenite and alkali-feldspar syenite. Mineral phases in these lithologies include clinopyroxene (Wo43-48En19-35Fs18-38), sanidine (An0Ab3-11Or89-97), and subordinate titanite, andradite and Na-feldspar. These rocks show homogeneous Sr but variable Nd isotopic compositions, and have relatively high zircon in situ oxygen isotopes (?18O = 5.2-6.7). The Gucheng plutonic rocks formed through fractional crystallization and accumulation from ultrapotassic magmas, which were originated from partial melting of metasomatic vein systems in the subcontinental lithospheric mantle of the North China Craton. These vein networks developed as a result of the reactions of fluids derived from subducted pelitic sediments on the downgoing Palaeo-Asian ocean floor with the enriched, subcontinental lithospheric mantle peridotites. Sensitive high-resolution ion microprobe (SHRIMP) U-Pb zircon dating has revealed a crystallization age of 415 Ma for the timing of the emplacement of the Gucheng pluton that marks the early stages of alkaline magmatism associated with the Andean-type continental margin evolution along the northern edge of the North China Craton facing the Palaeo-Asian Ocean.
DS201909-2109
2019
Yang, J.Yang, J., Lian, D., Robinson, P.T., Qiu, T., Xiong, F., Wu, W.A shallow origin for diamonds in ophiolitic chromitites. Geology, Vol. 47, pp. e475.North America, Mexicomicrodiamonds
DS201910-2280
2019
Yang, J.Lian, D., Yang, J.Ophiolite hosted diamond: a new window for probing carbon cycling in the deep mantle.Engineering, in press available, 23p. PdfMantlecoesite

Abstract: As reported in our prior work, we have recovered microdiamonds and other unusual minerals, including pseudomorph stishovite, moissanite, qingsongite, native elements, metallic alloys, and some crustal minerals (i.e., zircon, quartz, amphibole, and rutile) from ophiolitic peridotites and chromitites. These ophiolite-hosted microdiamonds display different features than kimberlitic, metamorphic, and meteoritic diamonds in terms of isotopic values and mineral inclusions. The characteristic of their light carbon isotopic composition implies that the material source of ophiolite-hosted diamonds is surface-derived organic matter. Coesite inclusions coexisting with kyanite rimming an FeTi alloy from the Luobusa ophiolite show a polycrystalline nature and a prismatic habit, indicating their origin as a replacement of stishovite. The occurrence in kyanite and coesite with inclusions of qingsongite, a cubic boron nitride mineral, and a high-pressure polymorph of rutile (TiO2 II) point to formation pressures of 10-15?GPa at temperatures ?1300?°C, consistent with depths greater than 380?km, near the mantle transition zone (MTZ). Minerals such as moissanite, native elements, and metallic alloys in chromite grains indicate a highly reduced environment for ophiolitic peridotites and chromitites. Widespread occurrence of diamonds in ophiolitic peridotites and chromitites suggests that the oceanic mantle may be a more significant carbon reservoir than previously thought. These ophiolite-hosted diamonds have proved that surface carbon can be subducted into the deep mantle, and have provided us with a new window for probing deep carbon cycling.
DS202003-0372
2020
Yang, J.Yang, J., Simakov, S.K., Moe, K., Scribano, V., Lian, D., Wu, W.Comment on the Comparison of enigmatic diamonds from Tolbachik arc volcano ( Litasov 2019) also Litasov responseGondwana Research, in press availableRussiaKamchatka
DS202005-0747
2020
Yang, J.Lin, J-F., Mao, Z., Yang, J., Fu, S.Elasticity of lower-mantle bridgmanite.Nature, Vol. 564, 7736, doi:10.1038/s41586-018-0741-7Mantlebridgmanite
DS202005-0773
2020
Yang, J.Yang, J., Faccenda, M.Intraplate volcanism originating from upwelling hydrous mantle transition zone.Nature, Vol. 579, 7797, pp. 1-4. pdfMantlewater, volcanism

Abstract: Most magmatism occurring on Earth is conventionally attributed to passive mantle upwelling at mid-ocean ridges, to slab devolatilization at subduction zones, or to mantle plumes. However, the widespread Cenozoic intraplate volcanism in northeast China1,2,3 and the young petit-spot volcanoes4,5,6,7 offshore of the Japan Trench cannot readily be associated with any of these mechanisms. In addition, the mantle beneath these types of volcanism is characterized by zones of anomalously low seismic velocity above and below the transition zone8,9,10,11,12 (a mantle level located at depths between 410 and 660 kilometres). A comprehensive interpretation of these phenomena is lacking. Here we show that most (or possibly all) of the intraplate and petit-spot volcanism and low-velocity zones around the Japanese subduction zone can be explained by the Cenozoic interaction of the subducting Pacific slab with a hydrous mantle transition zone. Numerical modelling indicates that 0.2 to 0.3 weight per cent of water dissolved in mantle minerals that are driven out from the transition zone in response to subduction and retreat of a tectonic plate is sufficient to reproduce the observations. This suggests that a critical amount of water may have accumulated in the transition zone around this subduction zone, as well as in others of the Tethyan tectonic belt13 that are characterized by intraplate or petit-spot volcanism and low-velocity zones in the underlying mantle.
DS202105-0799
2020
Yang, J.Wu, W., Yang, J., Zheng, J., Lian, D., Qiu, T.Origin of the diamonds within chromitite from the Mirdita ophiolite ( Albania) and its geological significance. Acta Geologica Sinica, Vol. 94, 1, pp. 64-65.Europe, Albaniadeposit - Mirdita

Abstract: Geophysical investigations and laboratory experiments show evidence for possible subduction of ancient oceanic crust. Geological and mineralogical observations suggest that subducted oceanic crust is recycled into the upper mantle. The subduction is supported by the recovery of super?deep diamonds from kimberlites and the presence of crustal materials in ophiolitic chromitites and their host peridotites. What is the mechanism? Here we report the new discovery of ophiolite?hosted diamonds in the podiform chromitites within the Skenderbeu massif from the Mirdita ophiolite in the western part of Neo?Tethys (Fig. 1). The diamonds are characterized by exceedingly light C isotopes (?13CPDB ? ?25‰), which can be interpreted as evidence for subduction of organic carbon from Earth's surface. The diamonds are also characterized by an exceptionally large range in ?15Nair (?12.9‰ to +25.5‰), accompanied by a low N aggregation state (Fig. 2). On the other hand, materials sparsely included in diamonds include amorphous material, Ni?Mn?Co alloy, nanocrystals (20 nm×20 nm) of calcium silicate with an orthorhombic perovskite structure (Ca?Pv), and fluids (Fig. 3). We consider that the Skenderbeu diamonds nucleated and grew from a C?saturated, NiMnCo?rich melt derived from a subducted slab of ocean crust and lithosphere in the deep mantle environment. The environment is in the diamond stability field or near the top of the mantle transition zone. The new discovery of diamonds from the Mirdita ophiolite provides a valuable opportunity to understand deep cycling of subducted oceanic crust and mantle (i.e., composition and process).
DS202202-0228
2022
Yang, J.Zhao, L., Tyler, I.M., Gorczk, W., Murdie, R.E., Gessner, K., Lu, Y., Smithies, H., Lia, T., Yang, J., Zhan, A., Wan, B., Sun, B., Yuan, H.Seismic evidence of two cryptic sutures in northwestern Australia: implications for the style of subduction during the Paleoproterozoic assembly of Columbia.Earth and planetary Science Letters, Vol. 579, 117343, 11p. PdfAustraliageophysics- seismics

Abstract: Plate tectonics, including rifting, subduction, and collision processes, was likely to have been different in the past due to the secular cooling of the Earth. The northeastern part of the West Australian Craton (WAC) has a complex Archean and Paleoproterozoic tectonic history; therefore, it provides an opportunity to study how subduction and collision processes evolved during the emergence of plate tectonics, particularly regarding the assembly of Earth's first supercontinent, Columbia. Because the northeastern boundary of the WAC and the southwestern boundary of the North Australian Craton (NAC) are covered by the Phanerozoic Canning Basin, the regional tectonic evolution has remained enigmatic, including how many tectonic elements were assembled and what may have driven rifting and subsequent collision events. Here, we use new passive-source seismic modeling to identify a seismically distinct segment of the lithosphere, the Percival Lakes Province, which lies east of the Pilbara Craton and is separated by two previously unknown southeast-trending lithosphere scale Paleoproterozoic sutures. We interpret that the northeastern suture, separates the Percival Lakes Province from the NAC, records the amalgamation of the WAC with the NAC. The southwestern suture separates the PLP from the reworked northeastern margin of the Pilbara Craton, including the East Pilbara Terrane and the Rudall Province. A significant upper mantle dipping structure was identified in the southwestern suture, and we interpret it to be a relic of subduction that records a previously unknown Paleoproterozoic collision that pre-dated the amalgamation of the WAC and NAC. By comparing our findings with previously documented dipping features, we show that the Paleoproterozoic collisions are seismically distinguishable from their Phanerozoic counterparts.
DS202205-0676
2022
Yang, J.Cao, C., Zeng, F., Liu, Y.W., Yang, J., Shenbiao, Y.Morphology and FTIR characteristics of the alluvial diamond from the Yangtze craton, China.Crystals, April 15p. PdfChinadiamond morphology

Abstract: A total of 48 natural alluvial diamonds from the Yangtze Craton, China, also called Hunan diamonds, were studied using morphology and IR spectroscopy. These diamond samples, collected downstream of the Yuan River, Hunan Province, with unknown host-rock source(s), were observed by scanning electron microscope (SEM) and Fourier-transform infrared spectroscopy (FTIR). Most Hunan diamonds are monocrystal forms of octahedra, tetrahexahedra (THH) and dodecahedra; octahedral-rhom-dodecahedral transitional behaviors and irregular forms are also visible. Trigons and tetragons, terraces and shield-shaped laminae are surface features that frequently indicate dissolution and reabsorption; green and brown spots, network patterns, and other mechanical abrasion marks are typical evidence of long-time deposition and transportation of Hunan diamonds. The main types of Hunan diamonds are type IaAB and type ?a. Diamond samples have a wide range of total nitrogen content (Ntot) from 196-1094 ppm. Two populations are distinguished by two-peak distribution models of NA (A-center concentrations) and %B (proportion of aggregated nitrogen). Hunan diamonds are low in structure hydrogen (0.03-4.67 cm?1, mostly below 1 cm?1) and platelets (0.23-17 cm?1, mostly below 2 cm?1). Moreover, there is a significant positive correlation between the hydrogen correlation peak and Ntot, which is similar to Argyle diamonds. The temperature conditions of the diamond formation have been estimated at 1075-1180 °C, mainly conforming to the kimberlite diamond range. Besides, some samples with slightly higher temperatures are close to the ultramafic-related Juina diamonds. Therefore, the FTIR characteristics analysis and comparison indicate the multiple sources of Hunan diamonds.
DS202205-0679
2022
Yang, J.Dutta, R., Tracy, S.J., Cohen, R.E. , Miozzi, F., Luo, K., Yang, J., Burnley, P.C., Smith, D., Meng, Y., Chariton, S., Prakapenka, V.B., Duffy, T.S.Ultrahigh-presssure disordered eight-coordinated phase of Mg2GeO4: analogue for super Earth mantles. GermaniumPNAS, https://doi.org/10.1073/pnas.2114424119Mantlegeodynamics

Abstract: Mg2GeO4 is important as an analog for the ultrahigh-pressure behavior of Mg2SiO4, a major component of planetary interiors. In this study, we have investigated magnesium germanate to 275 GPa and over 2,000 K using a laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction and density functional theory (DFT) computations. The experimental results are consistent with the formation of a phase with disordered Mg and Ge, in which germanium adopts eightfold coordination with oxygen: the cubic, Th3P4-type structure. DFT computations suggest partial Mg-Ge order, resulting in a tetragonal I4¯2d structure indistinguishable from I4¯3d Th3P4 in our experiments. If applicable to silicates, the formation of this highly coordinated and intrinsically disordered phase may have important implications for the interior mineralogy of large, rocky extrasolar planets.
DS202105-0800
2020
Yang, J.. Dongyang. L.Yang, J.. Dongyang. L., Robinson, P.T., Qiu, T. , Xiong, F., Wu, W.Geological evidence does not support a shallow origin for diamonds in ophiolite.Acta Geologica Sinica, Vol. 94, 1, pp. 70-72.Europe, Albaniaophiolite

Abstract: Farré?de?Pablo et al. (2018) report a new occurrence of in situ microdiamonds enclosed in chromite from ophiolitic chromitite pods hosted in the Tehuitzingo serpentinite of southern Mexico. The discovery enlarges the number of occurrence of the ophiolite?hosted microdiamonds to 7 countries in the world, including India (Das, 2015, 2017), Albania (Xiong et al., 2017; Wu et al., 2017), Turkey (Lian et al., 2017), Myanmar (Chen et al., 2018), Russia (Yang et al., 2015), and China (Bai et al., 1993; Xu et al., 2009). The microdiamonds occur in ophiolitic podiform chromitites and peridotites, and are generally interpreted as UHP phases formed at pressures > 4 GPa (Yang et al., 2014; Griffin et al., 2016; Das et al., 2017). However, Farré?de?Pablo et al. (2018) conclude that the Tehuitzingo diamonds were formed under low?temperature and low?pressure conditions during serpentinization, which challenges the current knowledge of diamond formation. Here, we discuss several lines of evidence that do not support the authors' conclusion.
DS200612-0838
2006
Yang, 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
DS200912-0436
2009
Yang, J.H.Li, Q.L., Li, X.H., Wu, F.Y., Yang, J.H.SIMS U-Th-Pb dating of kimberlite perovskite.Goldschmidt Conference 2009, p. A755 Abstract.Africa, South AfricaDeposit - Wesselton
DS1999-0817
1999
Yang, J.J.Yang, J.J., Jahn, B.M.Sinking intrusion model for the emplacement of garnet bearing peridotites into continent collision orogens...Geology, Vol. 27, No. 8, Aug. pp. 767-8.MantleSubduction, Petrology - peridotites
DS2000-1038
2000
Yang, J.J.Yang, J.J., Jahn, B.M.Deep subduction of mantle derived garnet peridotites from Su Lu ultra high pressure metamorphic terrane in China.Igc 30th. Brasil, Aug. abstract only 1p.Chinaultra high pressure (UHP) metamorphism
DS2003-0641
2003
Yang, J.J.Jahn, B., Fan, Q., Yang, J.J., Henin, O.Petrogenesis of the Maowu pyroxenite eclogite body from the UHP metamorphicLithos, Vol. 70, 3-4, pp. 243-67.ChinaUHP, geochronology
DS2003-1517
2003
Yang, J.J.Yang, J.J.Relict edenite in a garnet lherzolite from the Chinese Su Lu UHP metamorphic terrane:American Mineralogist, Vol.88, pp. 180-88.ChinaUHP - ultrahigh metamorphism
DS2003-1518
2003
Yang, J.J.Yang, J.J.Titanium clinohumite garnet pyroxene rock from the Su Lu UHP metamorphic terraneLithos, Vol. 70, 3-4, pp. 359-79.ChinaUHP, eclogites, metamorphism
DS2003-1519
2003
Yang, J.J.Yang, J.J., Enami, M.Chromian dissakisite ( Ce) in a garnet lherzolite from the Chinese Su Lu UHPAmerican Mineralogist, Vol. 88, 4, April, pp. 604-10.China, MantleUHP - ultra high pressure, REE
DS200412-0898
2003
Yang, J.J.Jahn, B., Fan, Q., Yang, J.J., Henin, O.Petrogenesis of the Maowu pyroxenite eclogite body from the UHP metamorphic terrane of Dabie Shan: chemical and isotopic constraLithos, Vol. 70, 3-4, pp. 243-67.ChinaUHP, geochronology
DS200412-2170
2003
Yang, J.J.Yang, J.J.Titanium clinohumite garnet pyroxene rock from the Su Lu UHP metamorphic terrane China: chemical evolution and tectonic implicatLithos, Vol. 70, 3-4, pp. 359-79.ChinaUHP, eclogites, metamorphism
DS200812-1291
2008
Yang, J.J.Yang, J.J., Powell, R.Ultrahigh pressure garnet peridotites from the devolatization of sea floor hydrated ultramafic rocks.Journal of Metamorphic Geology, Vol. 26, 6, pp. 695-716.ChinaQaidiam - peridotites
DS2003-1314
2003
Yang, J.S.Song, S.G., Yang, J.S., Xu, ZQ, Shi, R.D.Metamorphic evolution of the coesite bearing ultrahigh pressure terrane in the NorthJournal of Metamorphic Geology, Vol. 21, 6, pp. 631-44.ChinaUHP
DS2003-1547
2003
Yang, J.S.Zhang, R.Y., Liou, J.G., Yang, J.S., Ye, K.Ultrahigh pressure metamorphism in the forbidden zone: the Xugou garnet peridotiteJournal of Metamorphic Geology, Vol. 21, 6, pp. 539-50.ChinaUHP
DS200412-1880
2003
Yang, J.S.Song, S.G., Yang, J.S., Xu, ZQ, Shi, R.D.Metamorphic evolution of the coesite bearing ultrahigh pressure terrane in the North Qaidam northern Tibet, NW China.Journal of Metamorphic Geology, Vol. 21, 6, pp. 631-44.ChinaUHP
DS200412-2207
2003
Yang, J.S.Zhang, R.Y., Liou, J.G., Yang, J.S., Ye, K.Ultrahigh pressure metamorphism in the forbidden zone: the Xugou garnet peridotite.Journal of Metamorphic Geology, Vol. 21, 6, pp. 539-50.ChinaUHP
DS200512-1243
2005
Yang, J.S.Zhang, J.X., Yang, J.S., Mattison, C.G., Xu, Z.Q., Meng, F.C., Shi, R.D.Two contrasting eclogite cooling histories, north Qaidam HP/UHP terrane, western China: petrological and isotopic constraints.Lithos, Vol. 84, 1-2, Sept. pp. 51-76.ChinaEclogite, UHP, geochronology
DS200512-1246
2004
Yang, J.S.Zhang, R.Y., Liou, J.G., Yang, J.S., Liu, L., Jahn, B-M.Garnet peridotites in the UHP Mountain Belts of China.International Geology Review, Vol. 46, 11, pp. 981-1004.China, AsiaUHP
DS200512-1248
2005
Yang, J.S.Zhang, R.Y., Yang, J.S., Wooden, J.L., Liou, J.G., Li, T.F.U Pb SHRIMP geochronology of zircon in garnet peridotite from the Sulu UHP terrane, China: implications for mantle metasomatism and subduction.Earth and Planetary Science Letters, Vol. 237, 3-4, Sept. 15, pp. 729-743.Asia, ChinaUHP metamorphism, geochronology
DS200612-1604
2006
Yang, J.S.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
DS200712-1228
2007
Yang, J.S.Zhang, R.Y., Li, T., Rumble, D., Yui, T-F., Li, L., Yang, J.S., Pan, Y., Liou, J.G.Multiple metasomatism in Sulu ultrahigh P garnet peridotite constrained by petrological geochemiscal investigations.Journal of Metamorphic Geology, Vol. 25, 2, pp. 149-164..ChinaUHP
DS200812-0659
2008
Yang, J.S.Li, T.F., Yang, J.S., Zhang, R.Y.Geochemical characteristics, UHP metamorphic age, and genesis of the Huijialing garnet clinopyroxenite, Sulu terrane, China.International Geology Review, Vol. 50, 1, pp. 48-60.ChinaUHP
DS200812-1312
2008
Yang, J.S.Zhang, R.Y., Pan, Y.M., Yang, Y.H., Li, T.F., Liou, J.G., Yang, J.S.Chemical composition and ultrahigh P metamorphism of garnet peridotites from the Sulu UHP terrane, China: investigation of major, trace elements and Hf isotopesChemical Geology, in press available,ChinaUHP
DS200812-1313
2008
Yang, J.S.Zhang, R.Y., Pan, Y.M., Yang, Y.H., Li, T.F., Liou, J.G., Yang, J.S.Chemical composition and ultrahigh P metamorphism of garnet peridotites from the Sulu UHP terrane, China: investigation of major trace elements and Hf isotopes.Chemical Geology, Vol. 255, 1-2, Sept. 30, pp. 250-264.ChinaUHP
DS201112-1132
2011
Yang, J.S.Yang, J.S., Robinson, P.T.In situ diamonds and moissanite in podiform chromitites of the Loubusa and Ray-Iz ophiolites, Tibet and Russia.Goldschmidt Conference 2011, abstract p.2209.Russia, Asia, TibetDiamonds
DS201312-0337
2013
Yang, J.S.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
DS201601-0051
2015
Yang, J.S.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
DS201810-2390
2018
Yang, J.S.Yang, J.S., Trumball, R.B., Robinson, P.T., Xiong, F.H., Lian, D.Y.Comment: Ultra high pressure and ultra reduced minerals in ophiolites may form by lightning strikes. Super Reduced Minerals SURGeochemical Perspectives Letters, Vol. 8, pp. 6-7.Mantlemoissanite
DS202006-0959
2020
Yang, J.W.Yang, J.W., Park, J.H., Byun, M.G., Park, J., Yu, B.D., Hwan, N.M.Beyond carbon solvency effects of catalytic metal Ni on diamond growth.Diamonds & Related Materials, in press available, 27p. PdfGlobalnitrogen

Abstract: To understand the physical and chemical roles of catalytic metal Ni in the growth of diamond, ab-initio calculations of the structural, electronic, and kinetic properties of a Ni-covered C (111) surface were performed. Findings from this theoretical study highlight two important roles of Ni in addition to its carbon-solvency effect, widely known to play a catalytic role in the growth of diamond. The first role is to facilitate the formation of a thermodynamically stable Ni-C interface with a diamond bulk-like structure and the second is to induce surfactant-mediated growth enabling continuous layer-by-layer growth for diamond.
DS200712-1225
2007
Yang, J-F.Zhang, H-F., Nakamura, E., Sun, M., Kobayashi,K., Zhang, J., Yang, J-F., Tang, Y-J.Transformation of subcontinental lithospheric mantle through peridotite melt reaction: evidence from a highly fertile mantle xenolith from the North Chin a Craton.International Geology Review, Vol. 49, 7, July pp. 658-679.ChinaMelting
DS200612-1547
2006
Yang, J-H.Wu, F-Y., Walker, R.J., Yang, Y-H., Yuan, H-L., Yang, J-H.The chemical temporal evolution of lithospheric mantle underlying the North Chin a Craton.Geochimica et Cosmochimica Acta, Vol. 70, 19, pp. 5013-5034.ChinaDeposit - Tieling, Fuxian, Mengyin - geochemistry -SCLM
DS200612-1548
2006
Yang, J-H.Wu, F-Y., Yang, Y-H., Xie, L-W., Yang, J-H., Xu, P.Hf isotopic compositions of the standard zircons and baddeleyites used in U Pb geochronology.Chemical Geology, Vol. 234, 1-2, Oct 30, pp. 105-126.ChinaUHP, geochronology
DS200912-0836
2009
Yang, J-H.Yang, Y-H., Wu, F-Y., Wilde, S.A., Liu, X-M., Zhang, Y-B., Xie, L-W., Yang, J-H.In in situ perovskite Sr Nd isotopic constraints on the petrogenesis of the Ordovician Mengyin kimberlites in North Chin a craton.Chemical Geology, Vol. 264, 1-4, pp. 24-42.ChinaDeposit - Mengyin
DS201012-0861
2010
Yang, J-H.Wu, F.Y., Yang, Y-H., Mitchell, R.H., Li, J-H., Yang, J-H., Zhang, Y-B.In situ U Pb age determination and Nd isotopic analysis of perovskites from kimberlites in southern Africa and Somerset Island, Canada.Lithos, Vol. 115, pp. 205-222.Canada, Nunavut, Africa, South AfricaGeochronology
DS201212-0167
2012
Yang, J-H.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
DS201212-0834
2012
Yang, J-H.Zhu, R-X., Yang, J-H., Wu, F-Y.Timing of destruction of the North Chin a craton.Lithos, Vol. 149, pp. 51-60.ChinaSubduction
DS201412-0897
2014
Yang, J-H.Sun, J., Liu, C-Z., Tappe, S., Kostrovitsky, S.I., Wu, F-Y., Yakovlev, D., Yang, Y-H., Yang, J-H.Repeated kimberlite magmatism beneath Yakutia and its relationship to Siberian flood volcanism: insights from in situ U-Pb and Sr-Nd perovskite isotope analysis.Earth and Planetary Science Letters, Vol. 404, Oct. pp. 283-295.Russia, YakutiaKimberlite magmatism
DS201706-1114
2017
Yang, J-H.Zhu, Y-S., Yang, J-H., Sun- J-F., Wang, H.Zircon Hf-0 isotope evidence for recycled oceanic and continental crust in the sources of alkaline rocks.Geology, Vol. 45, 5, pp. 407-410.Mantlealkaline rocks
DS201709-2061
2017
Yang, J-H.Sun, J., Liu, C-Z., Kostrovisky, S.I., Wu, F-Y., Yang, J-H., Chu, Z., Yang, Y-H.Constraints from peridotites in the Obnazhennaya kimberlite.Goldschmidt Conference, abstract 1p.Russiadeposit - Obnazhennaya

Abstract: The characteristics of the sub-continental lithospheric mantle (SCLM) post-date the Siberian plume event (250 Ma) is still unclear; nearly all published data for mantle xenoliths are from a single kimberlite erupt before he Siberian plume (Udachnaya). We report major elements of the whole rock, trace elements data of clinopyroxene and Re-Os isotope and PGE concentration of mantle xenoliths from the Obnazhennaya kimberlite pipe (160 Ma). The Obnazhennaya mantle xenoliths, including spinel harzburgites, spinel dunites, spinel lherzolites, spinel-garnet lherzolite. The spinel harzburgites and dunites have refractory compositions, with 0.23-1.35 wt.% Al2O3, 0.41-3.11 wt.% CaO and 0.00-0.09 wt.% TiO2. Clinopyroxenes in harzburgites and dunites have lower Na2O but higher Cr2O3 contents. Modeling of the Y and Yb contents in clinopyroxenes indicates that the spinel harzburgites and dunites have been subjected to ca. 12-17% degrees of partial melting. The spinel harzburgites and dunites have 187Os/188Os of 0.11227-0.11637, giving a TRD age of 1.6-2.2 Ga. This suggests that old cratonic mantle still existed beneath the Obnazhennaya. In contrast, the lherzolites (both spinel- and spinel-garnet-) have more fertile compositions, containing 2.16-6.55 wt.% Al2O3, 2.91-7.55 wt.% CaO and 0.04-0.15 wt.% TiO2. Both spinel and spinelgarnet lherzolites have more radiogenic 187Os/188Os ratios (0.11931-0.17627), enriched P-PGEs. The higher Al2O3 and Os content and depleted IPGE character of these lherzolites suggest that they were not juvenile mantle accreted by Siberian mantle plume but the refertilized ancient mantle. Therefore, our result suggest that the cratonic mantle beneath the Obnazhennaya has not been replaced by juvenile mantle during the Siberian mantle plume.
DS201709-2062
2017
Yang, J-H.Sun, J., Liu, C-Z., Kostrovisky, S.I., Wu, F-Y., Yang, J-H., Chu, Z., Yang, Y-H.Composition of the lithospheric mantle in the northern Siberian craton: constraints from the peridotites in the Obnazhennaya kimberlite.Goldschmidt Conference, abstract 1p.Russia, Siberiadeposit - Obnazhennaya

Abstract: The characteristics of the sub-continental lithospheric mantle (SCLM) post-date the Siberian plume event (250 Ma) is still unclear; nearly all published data for mantle xenoliths are from a single kimberlite erupt before he Siberian plume (Udachnaya). We report major elements of the whole rock, trace elements data of clinopyroxene and Re-Os isotope and PGE concentration of mantle xenoliths from the Obnazhennaya kimberlite pipe (160 Ma). The Obnazhennaya mantle xenoliths, including spinel harzburgites, spinel dunites, spinel lherzolites, spinel-garnet lherzolite. The spinel harzburgites and dunites have refractory compositions, with 0.23-1.35 wt.% Al2O3, 0.41-3.11 wt.% CaO and 0.00-0.09 wt.% TiO2. Clinopyroxenes in harzburgites and dunites have lower Na2O but higher Cr2O3 contents. Modeling of the Y and Yb contents in clinopyroxenes indicates that the spinel harzburgites and dunites have been subjected to ca. 12-17% degrees of partial melting. The spinel harzburgites and dunites have 187Os/188Os of 0.11227-0.11637, giving a TRD age of 1.6-2.2 Ga. This suggests that old cratonic mantle still existed beneath the Obnazhennaya. In contrast, the lherzolites (both spinel- and spinel-garnet-) have more fertile compositions, containing 2.16-6.55 wt.% Al2O3, 2.91-7.55 wt.% CaO and 0.04-0.15 wt.% TiO2. Both spinel and spinelgarnet lherzolites have more radiogenic 187Os/188Os ratios (0.11931-0.17627), enriched P-PGEs. The higher Al2O3 and Os content and depleted IPGE character of these lherzolites suggest that they were not juvenile mantle accreted by Siberian mantle plume but the refertilized ancient mantle. Therefore, our result suggest that the cratonic mantle beneath the Obnazhennaya has not been replaced by juvenile mantle during the Siberian mantle plume.
DS201803-0488
2018
Yang, J-H.Yang, Y-H., Wu, F-Y., Yang, J-H., Mitchell, R.H., Zhao, Z-F., Xie, L-W., Huang, C., Ma, Q., Yang, M., Zhao, H.U-Pb age determination of schorlomite garnet by laser ablation inductively coupled plasma mass spectrometry. Magnet Cove, Fanshan, Ozernaya, Alno, Prairie LakeJournal of Analytical At. Spectrometry, Vol. 33, pp. 231-239.United States, Arkansas, China, Hebei, Russia, Kola Peninsula, Europe, Sweden, Canada, Ontariogeochronology

Abstract: We report the first U-Pb geochronological investigation of schorlomite garnet from carbonatite and alkaline complexes and demonstrate its applicability for U-Pb age determination using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) due to its relatively high U and Th abundances and negligible common Pb content. The comparative matrix effects of laser ablation of zircon and schorlomite are investigated and demonstrate the necessity of a suitable matrix-matched reference material for schorlomite geochronology. Laser-induced elemental fractional and instrumental mass discrimination were externally-corrected using an in house schorlomite reference material (WS20) for U-Pb geochronology. In order to validate the effectiveness and robustness of our analytical protocol, we demonstrate the veracity of U-Pb age determination for five schorlomite samples from: the Magnet Cove complex, Arkansas (USA); the Fanshan ultrapotassic complex, Hebei (China); the Ozernaya alkaline ultramafic complex, Kola Peninsula (Russia); the Alnö alkaline-rock carbonatite complex (Sweden); and the Prairie Lake carbonatite complex, Ontario (Canada). The schorlomite U-Pb ages range from 96 Ma to 1160 Ma, and are almost identical to ages determined from other accessory minerals in these complexes and support the reliability of our analytical protocol. Schorlomite garnet U-Pb geochronology is considered to be a promising new technique for understanding the genesis of carbonatites, alkaline rocks, and related rare-metal deposits.
DS201809-2119
2018
Yang, J-H.Zhu, Y-S., Yang, J-H., Wang, H., Wu, F-Y.A Paleoproterozoic basement beneath the Rangrim massif revealed by in situ U-Pb ages and Hf isotopes of xenocrystic zircons from Triassic kimberlites of the North Korea.Goldschmidt Conference, 1p. AbstractAsia, North Koreadeposit - Rangrim

Abstract: Zircon xenocrysts from the kimberlites offer a unique opportunity to identify the cryptic basement components hidden in the deep crust and thus to image lithospheric structure and crustal evolution. Zircon xenocrysts from the Triassic kimberlites, exposed in the Rangrim massif of North Korea, were selected for in situ U-Pb and Hf analyses. These zircon xenocrysts are all crust-derived. Their U-Pb age spectrum is characterized by one prominent age population at ca. 1.9-1.8 Ga without any Archean ages, indicating a Paleoproterozoic-dominated basement in the depth of the Rangrim massif. Archean basement should be very limited or absent at depth. This is different with the previous thought of the Rangrim massif being an Archean terrane. However, most of those Paleoproterozoic zircons display negative ?Hf(t) values (-9.7~+0.7) with the average Hf model age of 2.83 ± 0.09 Ga (2?), implying that protoliths of those zircons were not juvenile but derived from reworking of the pre-existed Archean basement. These observations argue for a strong crustal reworking event occurred in the Rangriam massif during Paleoproterozoic, which exhausted most of the preexisted Archean basement rocks and generated a large abundance of Paleoproterozoic rocks. The 1.9~1.8 Ga thermal event has been well documented in the adjacent Jiao- Liao-Ji orogenic belt of the North China Craton. Both of them are characterized by the widely distributed 1.9~1.8 Ga magmatism and share similar igneous rock assemblage. We suggest that the Rangrim massif may be the eastern extension of the Jiao-Liao-Ji belt in North Korea, constituting part of a huge Paleoproterozoic orogen in the eastern margin of the Sino-Korean craton.
DS201902-0336
2019
Yang, J-H.Zhu, Y-S., Yang, J-H., Wang, H., Wu, F-Y.A Paleoproterozoic basement beneath the Rangnim Massif revealed by the in-situ U-Pb ages and Hf isotopes of xenocrystic zircons from the Triassic kimberlites of North Korea.Geological Magazine, on line available Asia, Koreakimberlites

Abstract: In situ U-Pb and Hf analyses were used for crustal zircon xenocrysts from Triassic kimberlites exposed in the Rangnim Massif of North Korea to identify components of the basement hidden in the deep crust of the Rangnim Massif and to clarify the crustal evolution of the massif. The U-Pb age spectrum of the zircons has a prominent population at 1.9-1.8 Ga and a lack of Archaean ages. The data indicate that the deep crust and basement beneath the Rangnim Massif are predominantly of Palaeoproterozoic age, consistent with the ages of widely exposed Palaeoproterozoic granitic rocks. In situ zircon Hf isotope data show that most of the Palaeoproterozoic zircon xenocrysts have negative ?Hf ( t ) values (?9.7 to +0.7) with an average Hf model age of 2.86 ± 0.02 Ga (2 ? ), which suggests that the Palaeoproterozoic basement was not juvenile but derived from the reworking of Archaean rocks. Considering the existence of Archaean remanent material in the Rangnim Massif and their juvenile features, a strong crustal reworking event is indicated at 1.9-1.8 Ga, during which time the pre-existing Archaean basement was exhausted and replaced by a newly formed Palaeoproterozoic basement. These features suggest that the Rangnim Massif constitutes the eastern extension of the Palaeoproterozoic Liao-Ji Belt of the North China Craton instead of the Archaean Liaonan Block as previously thought. A huge Palaeoproterozoic orogen may exist in the eastern margin of the Sino-Korean Craton.
DS201907-1585
2019
Yang, J-H.Wu, F-Y., Yang, J-H., Xu, Y-G., Wilde, S.A., Walker, R.J.Destruction of the North China craton in the Mesozoic.Annual Reviews of Earth and Planetary Sciences, Vol. 47, pp. 173-195.Chinacraton

Abstract: The North China Craton (NCC) was originally formed by the amalgamation of the eastern and western blocks along an orogenic belt at ?1.9 Ga. After cratonization, the NCC was essentially stable until the Mesozoic, when intense felsic magmatism and related mineralization, deformation, pull-apart basins, and exhumation of the deep crust widely occurred, indicative of destruction or decratonization. Accompanying this destruction was significant removal of the cratonic keel and lithospheric transformation, whereby the thick (?200 km) and refractory Archean lithosphere mantle was replaced by a thin (<80 km) juvenile one. The decratonization of the NCC was driven by flat slab subduction, followed by a rollback of the paleo-Pacific plate during the late Mesozoic. A global synthesis indicates that cratons are mainly destroyed by oceanic subduction, although mantle plumes might also trigger lithospheric thinning through thermal erosion. Widespread crust-derived felsic magmatism and large-scale ductile deformation can be regarded as petrological and structural indicators of craton destruction.
DS201911-2579
2019
Yang, J-H.Zhu, Y-S., Yang, J-H., Wang, H., Wu, F-Y.A paleoproterozoic basement beneath the Rangnim Massif revealed by the in situ U-Pb ages and Hf isotopes of xenocrystic zircons from Triassic kimberlites of North Korea.Geological Magazine, Vol. 156, 10, pp. 1657-1667.Asia, Koreakimberlites

Abstract: n situ U-Pb and Hf analyses were used for crustal zircon xenocrysts from Triassic kimberlites exposed in the Rangnim Massif of North Korea to identify components of the basement hidden in the deep crust of the Rangnim Massif and to clarify the crustal evolution of the massif. The U-Pb age spectrum of the zircons has a prominent population at 1.9-1.8 Ga and a lack of Archaean ages. The data indicate that the deep crust and basement beneath the Rangnim Massif are predominantly of Palaeoproterozoic age, consistent with the ages of widely exposed Palaeoproterozoic granitic rocks. In situ zircon Hf isotope data show that most of the Palaeoproterozoic zircon xenocrysts have negative ?Hf(t) values (?9.7 to +0.7) with an average Hf model age of 2.86 ± 0.02 Ga (2?), which suggests that the Palaeoproterozoic basement was not juvenile but derived from the reworking of Archaean rocks. Considering the existence of Archaean remanent material in the Rangnim Massif and their juvenile features, a strong crustal reworking event is indicated at 1.9-1.8 Ga, during which time the pre-existing Archaean basement was exhausted and replaced by a newly formed Palaeoproterozoic basement. These features suggest that the Rangnim Massif constitutes the eastern extension of the Palaeoproterozoic Liao-Ji Belt of the North China Craton instead of the Archaean Liaonan Block as previously thought. A huge Palaeoproterozoic orogen may exist in the eastern margin of the Sino-Korean Craton.
DS201912-2835
2019
Yang, J-H.Yang, Y-H., Wu, F-Y., Qiu-Li, L., Rojas-Agramonte, Y., Yang, J-H., Yang, L., Ma, Q., Xie, L-W., Huang, C., Fan, H-R., Zhao, Z-F., Xu, C.In situ U-Th-Pb dating and Sr-Nd isotope analysis of bastnasite by LA-(MC)-ICP-MS.Geostandards and Geoanalltical Research, Vol. 43, 3, pp. 543-565.China, Europe, Sweden, Asia, Mongolia, United States, Africa, Malawi, MadagascarREE

Abstract: Bastnäsite is the end member of a large group of carbonate-fluoride minerals with the common formula (REE) CO3F•CaCO3. This group is generally widespread and, despite never occurring in large quantities, represents the major economic light rare earth element (LREE) mineral in deposits related to carbonatite and alkaline intrusions. Since bastnäsite is easily altered and commonly contains inclusions of earlier?crystallised minerals, in situ analysis is considered the most suitable method to measure its U?Th?Pb and Sr?Nd isotopic compositions. Electron probe microanalysis and laser ablation (multi?collector) inductively coupled plasma?mass spectrometry of forty?six bastnäsite samples from LREE deposits in China, Pakistan, Sweden, Mongolia, USA, Malawi and Madagascar indicate that this mineral typically has high Th and LREE and moderate U and Sr contents. Analysis of an in?house bastnäsite reference material (K?9) demonstrated that precise and accurate U?Th?Pb ages could be obtained after common Pb correction. Moreover, the Th?Pb age with its high precision is preferable to the U?Pb age because most bastnäsites have relatively high Th rather than U contents. These results will have significant implications for understanding the genesis of endogenous ore deposits and formation processes related to metallogenic geochronology research.
DS2003-1520
2003
Yang, J-J.Yang, J-J., Enami, M.Chromian dissakisite (Ce) in a garnet lherzolite from the Chinese Su-Lu UHPAmerican Mineralogist, Vol. 88, pp. 604-10.ChinaUHP, Su-Lu Zhimafang
DS2003-1560
2003
Yang, J-J.Zheng, Y-F., Yang, J-J., Gong, B., Jahn, B-M.Partial equilibrium of radiogenic and stable isotope systems in garnet peridotite duringAmerican Mineralogist, Vol. 88, pp. 1633-43.ChinaGeochronology, UHP
DS200412-2171
2003
Yang, J-J.Yang, J-J., Enami, M.Chromian dissakisite (Ce) in a garnet lherzolite from the Chinese Su-Lu UHP metamorphic terrane: implications for Cr incorporatiAmerican Mineralogist, Vol. 88, pp. 604-10.ChinaUHP, Su-Lu Zhimafang
DS200412-2227
2003
Yang, J-J.Zheng, Y-F., Yang, J-J., Gong, B., Jahn, B-M.Partial equilibrium of radiogenic and stable isotope systems in garnet peridotite during ultrahigh pressure metamorphism.American Mineralogist, Vol. 88, pp. 1633-43.ChinaGeochronology, UHP, Shimafang, Sulu
DS200612-1563
2006
Yang, J-J.Yang, J-J.Ca rich garnet clinopyroxene rocks at Hujialin in the Su Lu terrane (eastern China): deeply subducted arc cumulates?Journal of Petrology, Vol. 47, 5, pp. 965-990.Asia, ChinaUHP, subduction
DS201412-0382
2014
Yang, J-J.Huang, M-X., Yang, J-J., Powell, R., Mo, X.High pressure metamorphism of serpentinzed chromitite at Luobusha ( southern Tibet).American Journal of Science, Vol. 314, pp. 400-433.Asia, TibetDiamond and coesite
DS201412-1000
2014
Yang, J-J.Yang, J-J., Fan, Z.F., Yu, C., Yan, R.Coseismic formation of eclogite facies cataclastic dykes at Yangkou in the Chinese Sulu UHP metamorphic belt.Journal of Metamorphic Geology, Vol. 32, 9, pp. 937-960.ChinaUHP
DS201412-1001
2014
Yang, J-J.Yang, J-J., Huang, M-X., Wu, Q-Y., Zhang, H-R.Coesite bearing eclogite breccia: implication for coseismic ultrahigh-pressure metamorphism and the rate of process.Contributions to Mineralogy and Petrology, Vol. 167, pp. 1013-MantleEclogite
DS200712-1198
2007
Yang, J-S.Yang, J-S., Dobrzhinetskaya, L.Diamond and coesite bearing chromitites from the Luobusa ophiolite, Tibet.Geology, Vol. 35, 10, Oct. pp. 875-878.Asia, TibetUHP
DS200912-0776
2009
Yang, J-S.Trumball, R.B., Yang, J-S., Robinson, P.T., Di Pierro, S., Vennemann, T., Wiedenbeck, M.The carbon isotope composition of natural SiC (moissanite) from the Earth's mantle: new discoveries from ophiolites.Lithos, In press - available 31p.MantleMoissanite
DS201112-0871
2004
Yang, J-S.Robinson, P.T., Bai, W-J., Malpas, J., Yang, J-S., Zhou, M-F., Fang, Q-S., Hu, X-F., Cameron, StaudigelUltra high pressure minerals in the Loubasa ophiolite, Tibet and their tectonic implications.Aspects of the Tectonic evolution of China, Editors Fletcher, Ali, Aitchison, Geological Society Of America, Spec. Pub.226, pp.247-71China, TibetUHP
DS201502-0093
2014
Yang, J-S.Robinson, P.T., Trumbull, R.B., Schmitt, A., Yang, J-S., Li, J-W., Zhou, M-F., Erzinger, J., Dare, S., Xiong, F.The origin and significance of crustal minerals in ophiolitic chromitites and peridotites.Gondwana Research, Vol. 27 2, pp. 486-506.Peridotite
DS201510-1816
2015
Yang, J-S.Yang, J-S., Wirth, R., Xu, X., Tian, Y., Huang, Z., Robinson, P.T., Dilek, Y.Formation of ophiolite hosted diamonds by deep subduction of oceanic lithosphere: evidence from mineral inclusions.GSA Annual Meeting, Paper 81-2, 1p. Abstract onlyMantleMineral inclusions

Abstract: In recent years we have confirmed the existence of ophiolite-hosted diamonds on Earth, which occur in mantle peridotites and podiform chromitites of many ophiolites. These diamonds differ significantly from most kimberlite varieties, particularly in their inclusions. The typical inclusions in the diamonds are Mn-rich phases, i.e., NiMnCo alloy, native Mn, MnO, galaxite, Mn olivine and Mn garnet. Ca-silicate perovskite, a typical lower mantle mineral, was identified as mineral inclusions in diamond. One occurs as a 60-nanometer, euhedral grain associated with NiMnCo alloy and graphite, while another one occurs as a 50-nanometer grain within a large inclusion containing both NiMnCo alloy and Nd-Se-Cu-S phase. By EDS the perovskite has Ca 48.3%, Si 37.7% and Mn 14.1% with oxygen. TEM diffraction data show that the inclusion has d-spacings and angles between adjacent lattice planes are consistent to the Ca-silicate perovskite with an orthorhombic structure. The only known source of such light carbon is organic material in surface sediments and the best known sources of abundant manganese are Fe-Mn-rich sediments and Mn nodules, both of which are common on the seafloor. Many parts of the modern seafloor are also covered by sediments with a continental provenance. Phases such as SiO2 and Al2O3 are not expected in mantle peridotites and must have been introduced from shallow levels. We propose that subduction of oceanic lithosphere carries C, Mn, Si, Al and REE to the transition zone or lower mantle where the material is mixed with highly reduced material, perhaps derived from greater depths. Crystallization of diamond from a C-rich fluid encapsulates the observed inclusions. The diamonds and associated minerals are incorporated into chromite grains during chromite crystallization at depth of mantle transition zone, and are carried to shallower levels by mantle convection. Accumulation of chromite grains produces podiform chromitites containing a range of exotic minerals. However, the presence of diamonds and other UHP minerals in ophiolitic peridotites indicates that such phases can persist far outside their normal stability fields.
DS201606-1090
2016
Yang, J-S.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?
DS201705-0858
2017
Yang, J-S.Moe, K., Yang, J-S., Johnson, P., Wang, W.Spectroscopic analysis of microdiamonds in ophiolitic chromitite and peridotite.Lithosphere, 9p.Asia, Tibet, Russia, UralsMicrodiamonds

Abstract: Microdiamonds ?200 ?m in size, occurring in ophiolitic chromitites and peridotites, have been reported in recent years. Owing to their unusual geological formation, there are several debates about their origin. We studied 30 microdiamonds from 3 sources: (1) chromitite ore in Luobusa, Tibet; (2) peridotite in Luobusa, Tibet; and (3) chromitite ore in Ray-Iz, polar Ural Mountains, Russia. They are translucent, yellow to greenish-yellow diamonds with a cubo-octahedral polycrystalline or single crystal with partial cubo-octahedral form. Infrared (IR) spectra revealed that these diamonds are type Ib (i.e., diamonds containing neutrally charged single substitutional nitrogen atoms, Ns0, known as the C center) with unknown broad bands observed in the one-phonon region. They contain fluid inclusions, such as water, carbonates, silicates, hydrocarbons, and solid CO2. We also identified additional microinclusions, such as chromite, magnetite, feldspar (albite), moissanite, hematite, and magnesiochromite, using a Raman microscope. Photoluminescence (PL) spectra measured at liquid nitrogen temperature suggest that these diamonds contain nitrogen-vacancy, nickel, and H2 center defects. We compare them with high-pressure-high-temperature (HPHT) synthetic industrial diamond grits. Although there are similarities between microdiamonds and HPHT synthetic diamonds, major differences in the IR, Raman, and PL spectra confirm that these microdiamonds are of natural origin. Spectral characteristics suggest that their geological formation is different but unique compared to that of natural gem-quality diamonds. Although these microdiamonds are not commercially important, they are geologically important in that they provide an understanding of a new diamond genesis.
DS2000-0602
2000
Yang, K.Ma, C., Ehlers, C., Xu, C., Li, Z., Yang, K.The roots of the Dabie Shan ultrahigh pressure metamorphic terrane: constraints from geochemistry ...Precambrian Research, Vol. 102, No. 3-4, Aug.pp. 279-301.Chinaultra high pressure (UHP), geochronology, Dabie Shan region
DS200712-1153
2007
Yang, K.White, N.C., Yang, K.Exploring in China: the challenges and rewards.SEG Newsletter, No.70, July pp. 1, 8-15.ChinaOverview - not specific to diamonds
DS201112-1100
2011
Yang, K.Wang, K., Fan, H., Yang, K., Hu, F., Ma, Y.Bayan Obo carbonatites: texture evidence from polyphase intrusive and extrusive carbonatites.Acta Geologica Sinica, Vol. 84, 6, pp. 1365-1376.Asia, ChinaCarbonatite
DS202001-0047
2020
Yang, K.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
Yang, K.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.
DS201112-1134
2011
Yang, K-F.Yang, K-F., Fan, H-R., Santosh, M., Hu, F-F., Wang, K-Y.Mesoproterozoic mafic and carbonatitic dykes from the northern margin of the North Chin a craton: implications for the fin al breakup of Columbia supercontinent.Tectonophysics, Vol. 498, pp. 1-10.ChinaCarbonatite, Bayan Obo
DS201412-0236
2014
Yang, K-F.Fan, H-R., Hu, F-F., Yang, K-F., Pirajno, F., Liu, X., Wang, K-Y.Integrated U-Pb and Sm-Nd geochronology for a REE rich carbonatite dyke at the giant Bayan Obo REE deposit, northern China.Lithos, in press availableChinaDeposit - Bayan Obo
DS201412-0238
2014
Yang, K-F.Fan, H-R., Hu, F-F., Yang, K-F., Pirajno, F., Liu, X., Wang, K-Y.Integrated U Pb and Sm Nd geochronology of a REE rich carbonatite dyke at the gaint Bayan Obo REE deposit, northern China.Ore Geology Reviews, Vol. 63, pp. 510-519.ChinaCarbonatite
DS202010-1857
2020
Yang, K-F.Liu, S., Ding, L., Fan, H-R., Yang, K-F., Tang, Y-W. She, H-D, Hao, M-z.Hydrothermal genesis of Nb mineralization in the giant Bayan Obo REE-Nb-Fe deposit ( China): implicated by petrography and geochemistry of Nb-bearing minerals.Precambrian Research, Vol. 348, 105864 24p. PdfChinadeposit - Bayan Obo

Abstract: The Bayan Obo REE-Nb-Fe deposit, which reserves the current largest REE resources globally, also hosts over 70% of China’s Nb resources. Unlike many world-class carbonatite-related Nb deposits (e.g. Morro dos Seis Lagos and Araxá, Brazil) with igneous or secondary origin, Nb was mainly stored in Nb-bearing minerals (aeschynite, ilmenorutile, baotite, fergusonite etc.) of hydrothermal origin at Bayan Obo, supported by evidence from petrography, element and isotopic geochemistry. Although igneous fersmite and columbite were occasionally discovered in local carbonatite dykes, the Mesoproterozoic and Paleozoic hydrothermal metasomatism occurred in the ore-hosting dolomite, related to carbonatite intrusion and the closure of Paleo-Asian Ocean respectively, has played a more significant role during the ultimate Nb enrichment. REE, however, was significantly enriched during both the carbonatite-related magmatic and hydrothermal processes. Consequently, there was differentiated mineralization between REE and Nb in the carbonatite dykes and the ores. Niobium mineralization at Bayan Obo is rather limited in Mesoproterozoic carbonatite, whereas more extensive in the metasomatized ore-hosting dolomite, and generally postdating the REE mineralization at the same stage. According to mineral geochemistry, Bayan Obo aeschynite was classified into 3 groups: aeschynite-(Nd) with convex REE patterns (Group 1); aeschynite-(Ce) (Group 2) and nioboaeschynite (Group 3) with nearly flat REE patterns. Aeschynite (Group 1), ilmenorutile and fergusonite precipitated from Paleozoic hydrothermal fluids with advanced fractionation of Ce-rich REE minerals. The Mesoproterozoic hydrothermal Nb mineralization, represented by aeschynite (Group 3) and baotite, occurred postdating REE mineralization at same stage. Besides, fersmite and aeschynite (Group 2) precipitated from the Mesoproterozoic REE-unfractionated melt and hydrothermal fluids, respectively. All above Nb-bearing minerals exhibit extreme Nb-Ta fractionation as a primary geochemical characteristic of mantle-derived carbonatite. The forming age of the aeschynite megacrysts (Group 1) has not been accurately determined. However, the potential age was constrained to ~430 Ma or alternatively ~270-280 Ma subjected to subduction and granite activity, respectively. These aeschynite crystals inherited REEs from multiphase former REE mineralization, with an intermediate apparent Sm-Nd isochron age between the Mesoproterozoic and the Paleozoic REE mineralization events.
DS202012-2254
2020
Yang, K-F.Wang, Z-Y., Fan, H-R., Zhou, L., Yang, K-F., She, H-D.Carbonatite-related REE deposits: an overview.MDPI Minerals, Vol. 10, 965 doi:103390/min10110965, 26p. PdfChinacarbonatite, REE

Abstract: The rare earth elements (REEs) have unique and diverse properties that make them function as an “industrial vitamin” and thus, many countries consider them as strategically important resources. China, responsible for more than 60% of the world’s REE production, is one of the REE-rich countries in the world. Most REE (especially light rare earth elements (LREE)) deposits are closely related to carbonatite in China. Such a type of deposit may also contain appreciable amounts of industrially critical metals, such as Nb, Th and Sc. According to the genesis, the carbonatite-related REE deposits can be divided into three types: primary magmatic type, hydrothermal type and carbonatite weathering-crust type. This paper provides an overview of the carbonatite-related endogenetic REE deposits, i.e., primary magmatic type and hydrothermal type. The carbonatite-related endogenetic REE deposits are mainly distributed in continental margin depression or rift belts, e.g., Bayan Obo REE-Nb-Fe deposit, and orogenic belts on the margin of craton such as the Miaoya Nb-REE deposit. The genesis of carbonatite-related endogenetic REE deposits is still debated. It is generally believed that the carbonatite magma is originated from the low-degree partial melting of the mantle. During the evolution process, the carbonatite rocks or dykes rich in REE were formed through the immiscibility of carbonate-silicate magma and fractional crystallization of carbonate minerals from carbonatite magma. The ore-forming elements are mainly sourced from primitive mantle, with possible contribution of crustal materials that carry a large amount of REE. In the magmatic-hydrothermal system, REEs migrate in the form of complexes, and precipitate corresponding to changes of temperature, pressure, pH and composition of the fluids. A simple magmatic evolution process cannot ensure massive enrichment of REE to economic values. Fractional crystallization of carbonate minerals and immiscibility of melts and hydrothermal fluids in the hydrothermal evolution stage play an important role in upgrading the REE mineralization. Future work of experimental petrology will be fundamental to understand the partitioning behaviors of REE in magmatic-hydrothermal system through simulation of the metallogenic geological environment. Applying "comparative metallogeny" methods to investigate both REE fertile and barren carbonatites will enhance the understanding of factors controlling the fertility.
DS201912-2799
2019
Yang, L.Liu, J., Hu, Q., Bi, W., Yang, L., Xiao, Y., Chow, P., Meng, Y., Prakapenka, V.B., Mao, H-K., Mao, W.L.Altered chemistry of oxygen and iron under deep Earth conditionsNature Communications, 8p. PdfMantlegeochemistry

Abstract: A drastically altered chemistry was recently discovered in the Fe-O-H system under deep Earth conditions, involving the formation of iron superoxide (FeO2Hx with x?=?0 to 1), but the puzzling crystal chemistry of this system at high pressures is largely unknown. Here we present evidence that despite the high O/Fe ratio in FeO2Hx, iron remains in the ferrous, spin-paired and non-magnetic state at 60-133?GPa, while the presence of hydrogen has minimal effects on the valence of iron. The reduced iron is accompanied by oxidized oxygen due to oxygen-oxygen interactions. The valence of oxygen is not -2 as in all other major mantle minerals, instead it varies around -1. This result indicates that like iron, oxygen may have multiple valence states in our planet’s interior. Our study suggests a possible change in the chemical paradigm of how oxygen, iron, and hydrogen behave under deep Earth conditions.
DS201912-2835
2019
Yang, L.Yang, Y-H., Wu, F-Y., Qiu-Li, L., Rojas-Agramonte, Y., Yang, J-H., Yang, L., Ma, Q., Xie, L-W., Huang, C., Fan, H-R., Zhao, Z-F., Xu, C.In situ U-Th-Pb dating and Sr-Nd isotope analysis of bastnasite by LA-(MC)-ICP-MS.Geostandards and Geoanalltical Research, Vol. 43, 3, pp. 543-565.China, Europe, Sweden, Asia, Mongolia, United States, Africa, Malawi, MadagascarREE

Abstract: Bastnäsite is the end member of a large group of carbonate-fluoride minerals with the common formula (REE) CO3F•CaCO3. This group is generally widespread and, despite never occurring in large quantities, represents the major economic light rare earth element (LREE) mineral in deposits related to carbonatite and alkaline intrusions. Since bastnäsite is easily altered and commonly contains inclusions of earlier?crystallised minerals, in situ analysis is considered the most suitable method to measure its U?Th?Pb and Sr?Nd isotopic compositions. Electron probe microanalysis and laser ablation (multi?collector) inductively coupled plasma?mass spectrometry of forty?six bastnäsite samples from LREE deposits in China, Pakistan, Sweden, Mongolia, USA, Malawi and Madagascar indicate that this mineral typically has high Th and LREE and moderate U and Sr contents. Analysis of an in?house bastnäsite reference material (K?9) demonstrated that precise and accurate U?Th?Pb ages could be obtained after common Pb correction. Moreover, the Th?Pb age with its high precision is preferable to the U?Pb age because most bastnäsites have relatively high Th rather than U contents. These results will have significant implications for understanding the genesis of endogenous ore deposits and formation processes related to metallogenic geochronology research.
DS202204-0547
2022
Yang, L.Zhang, W., Mei, T., li, B., Yang, L., Du, S., Miao, Y., Chu, H.Effect of current density and agitation modes on the structural and corrosion behavior of Ni/diamond composite coatings. Nanoparticles ( nickel)Journal of Materials Research and Technology, Vol. 12, pp. 1473-1485.Chinananodiamonds

Abstract: In this work, Ni/diamond composite coatings have been synthesized by electrodeposition in direct current mode. The effects of mechanical and ultrasonic agitations on the microstructural, surface characteristics and electrochemical properties have been comparatively investigated by various methods. Results show that diamond nanoparticles have been evenly dispersed in Ni metallic matrix, which could reinforce their performances. The coatings prepared under ultrasonic and mechanical agitation both exhibit compact, dense and hill-valley like morphology with pyramid-like nickel crystallite grains. The relative texture coefficient (RTC) values show that the preferred orientation of the Ni/diamond coating was (200) texture. From 3 to 5 A dm?2, the crystallite sizes of ultrasonic conditions were 59.2-81.7 nm, which were smaller than 76.3-83.2 nm of magnetic agitations. The average roughness (Ra = 78.9-133 nm) of ultrasonic-assisted coatings were lower than 103-139 nm of magnetic conditions. The mechanism of the co-electrodeposition process was proposed. Electrochemical impedance spectroscopy (EIS) results illustrate that the ultrasonic-assisted electrodeposited Ni/diamond coating has better corrosion resistance than that prepared under mechanical stirring conditions. The Ni/diamond composite coatings could be applied as protective materials in harsh mediums.
DS200812-1235
2007
Yang, L-K.Wang, F., Lu, X-X., Lo, C-H., Wu, F-Y., He, H-Y., Yang, L-K., Zhu, R-X.Post collisional, potassic monzonite-minette complex Shahewan in the Qinling Mountains: 40Ar 39Ar thermochronology, petrogenesis, implications - dynamicJournal of Asian Earth Sciences, Vol. 31, 2, October pp. 153-166.ChinaMinette
DS201803-0488
2018
Yang, M.Yang, Y-H., Wu, F-Y., Yang, J-H., Mitchell, R.H., Zhao, Z-F., Xie, L-W., Huang, C., Ma, Q., Yang, M., Zhao, H.U-Pb age determination of schorlomite garnet by laser ablation inductively coupled plasma mass spectrometry. Magnet Cove, Fanshan, Ozernaya, Alno, Prairie LakeJournal of Analytical At. Spectrometry, Vol. 33, pp. 231-239.United States, Arkansas, China, Hebei, Russia, Kola Peninsula, Europe, Sweden, Canada, Ontariogeochronology

Abstract: We report the first U-Pb geochronological investigation of schorlomite garnet from carbonatite and alkaline complexes and demonstrate its applicability for U-Pb age determination using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) due to its relatively high U and Th abundances and negligible common Pb content. The comparative matrix effects of laser ablation of zircon and schorlomite are investigated and demonstrate the necessity of a suitable matrix-matched reference material for schorlomite geochronology. Laser-induced elemental fractional and instrumental mass discrimination were externally-corrected using an in house schorlomite reference material (WS20) for U-Pb geochronology. In order to validate the effectiveness and robustness of our analytical protocol, we demonstrate the veracity of U-Pb age determination for five schorlomite samples from: the Magnet Cove complex, Arkansas (USA); the Fanshan ultrapotassic complex, Hebei (China); the Ozernaya alkaline ultramafic complex, Kola Peninsula (Russia); the Alnö alkaline-rock carbonatite complex (Sweden); and the Prairie Lake carbonatite complex, Ontario (Canada). The schorlomite U-Pb ages range from 96 Ma to 1160 Ma, and are almost identical to ages determined from other accessory minerals in these complexes and support the reliability of our analytical protocol. Schorlomite garnet U-Pb geochronology is considered to be a promising new technique for understanding the genesis of carbonatites, alkaline rocks, and related rare-metal deposits.
DS1975-1268
1979
YANG, Meie.Zhang ruyuan, YANG, Meie.The Calculation Method of Composition of GarnetScientia Geol. Sinica., Vol. 15, No. 1, PP. 98-99.ChinaGarnet, Endmember Calculation, Element Ratios
DS200712-0882
2007
Yang, P.Reguir, E., Halden, N., Chakmouradian, A., Yang, P., Zaitsev, A.N.Contrasting evolutionary trends in magnetite from carbonatites and alkaline silicate rocks.Plates, Plumes, and Paradigms, 1p. abstract p. A826.Africa, TanzaniaCarbonatite
DS200812-0192
2008
Yang, P.Chakhmouradian, A.H., Bohm, C.O., Demeny, A., Reguir, E.P., Hegger, E., Halden, N.M., Yang, P.Kimberlite from Wekusko Lake, Manitoba: a diamond indicator bearing beforsite and not a kimberlite, after all.9IKC.com, 3p. extended abstractCanada, manitobaCarbonatite
DS200812-0194
2008
Yang, P.Chakhmouradian, A.R., Demeny, A., Reguir, E.P., Hegner, E., Halden, N.M., Yang, P.'Kimberlite' from Wekusko Lake, Manitoba: re-assessment and implications for further exploration. Beforsite ( primary dolomite carbonatite)... 'notion' could beManitoba Geological Survey, Nov. 21, 1p. abstract.Canada, ManitobaPetrology - potentially diamondiferous
DS200812-0946
2008
Yang, P.Reguir, E., Chakhmouradian, A., Halden, N., Malkovets, V., Yang, P.Major and trace element compositional variation of phlogopite from kimberlites and carbonatites as a petrogenetic indicator.9IKC.com, 3p. extended abstractCanada, AfricaGeochemistry - ferromagnesian micas
DS200812-0947
2008
Yang, P.Reguir, E.P., Chakhmouradian, A.R., Halden, N.M., Yang, P., Zaitsev, A.N.Early magmatic and reaction induced trends in magnetite from the carbonatites of Kerimasi, Tanzania.Canadian Mineralogist, Vol. 46, 4, August pp.Africa, TanzaniaCarbonatite
DS200912-0623
2009
Yang, P.Reguir, E.P., Chakmouradian, A.R., Halden, N.M., Malkovets, V.G., Yang, P.Major and trace element compositional variation of phlogopite from kimberlites and carbonatites as a petrogenetic indicator.Lithos, In press available, 50p.TechnologyGeochemistry - ferromagnesian micas
DS201012-0094
2009
Yang, P.Chakhmouradian, A.R., Bohm, C.O., Demeny, A., Reguir, E.P., Hegner, E., Creaser, R.A., Halden, N.M., Yang, P.'Kimberlite' from Wekusko Lake Manitoba: actually a diamond indicator bearing dolomite carbonatite.Lithos, Vol. 112 S pp. 347-357.Canada, ManitobaCarbonatite
DS201012-0619
2010
Yang, P.Reguir, E.P., Chakhmouradian, A.R., Halden, N.M., Yang, P.Trace element variations in clinopyroxene from calcite carbonatites.International Mineralogical Association meeting August Budapest, abstract p. 575.Canada, Ontario, Russia, Aldan Shield, Kola PeninsulaCarbonatite
DS201012-0620
2010
Yang, P.Reguir, E.P., Chakhmouradian, A.R., Halden, N.M., Yang, P.Contrasting trends of trace element zoning in phlogopite from calcite carbonatites.International Mineralogical Association meeting August Budapest, abstract p. 575.United States, Colorado Plateau, Russia, Canada, Ontario, QuebecCarbonatite
DS201312-0674
2013
Yang, P.Osovetskii, B.M., Reguir, E.P., Chakhmouradian, A.R., Veksler, I.V., Yang, P., Kamanetsky, V.S., Camacho, A.Trace element analysis and U-Pb geochronology of perovskite and its importance for tracking unexposed rare metal and diamond deposits.GAC-MAC 2013 SS4: Diamond: from birth to the mantle emplacement in kimberlite., abstract onlyMantleGeochronology
DS201412-0112
2014
Yang, P.Chakhmouradian, A.R., Reguir, E.P., Kressal, R.D., Crozier, J., Pisiak, L.K., Sidhu, R., Yang, P.Carbonatite hosted niobium deposit at Aley, northern British Columbia ( Canada): mineralogy, geochemistry and petrogenesis.Ore Geology Reviews, Vol. 64, pp. 642-666.Canada, British ColumbiaCarbonatite
DS201508-0344
2015
Yang, P.Chakhmouradian, A.R., Reguir, E.P., Coueslan, C., Yang, P.Calcite and dolomite in intrusive carbonatites. II Trace element variations.Mineralogy and Petrology, in press available 17p.GlobalCarbonatite

Abstract: The composition of calcite and dolomite from several carbonatite complexes (including a large set of petrographically diverse samples from the Aley complex in Canada) was studied by electron-microprobe analysis and laser-ablation inductively-coupled-plasma mass-spectrometry to identify the extent of substitution of rare-earth and other trace elements in these minerals and the effects of different igneous and postmagmatic processes on their composition. Analysis of the newly acquired and published data shows that the contents of rare-earth elements (REE) and certain REE ratios in magmatic calcite and dolomite are controlled by crystal fractionation of fluorapatite, monazite and, possibly, other minerals. Enrichment in REE observed in some samples (up to ~2000 ppm in calcite) cannot be accounted for by coupled substitutions involving Na, P or As. At Aley, the REE abundances and chondrite-normalized (La/Yb)cn ratios in carbonates decrease with progressive fractionation. Sequestration of heavy REE from carbonatitic magma by calcic garnet may be responsible for a steeply sloping "exponential" pattern and lowered Ce/Ce* ratios of calcite from Magnet Cove (USA) and other localities. Alternatively, the low levels of Ce and Mn in these samples could result from preferential removal of these elements by Ce4+- and Mn3+-bearing minerals (such as cerianite and spinels) at increasing f(O2) in the magma. The distribution of large-ion lithophile elements (LILE = Sr, Ba and Pb) in rock-forming carbonates also shows trends indicative of crystal fractionation effects (e.g., concomitant depletion in Ba + Pb at Aley, or Sr + Ba at Kerimasi), although the phases responsible for these variations cannot be identified unambiguously at present. Overall, element ratios sensitive to the redox state of the magma and its complexing characteristics (Eu/Eu*, Ce/Ce* and Y/Ho) are least variable and in both primary calcite and dolomite, approach the average chondritic values. In consanguineous rocks, calcite invariably has higher REE and LILE levels than dolomite. Hydrothermal reworking of carbonatites does not produce a unique geochemical fingerprint, leading instead to a variety of evolutionary trends that range from light-REE and LILE enrichment (Turiy Mys, Russia) to heavy-REE enrichment and LILE depletion (Bear Lodge, USA). These differences clearly attest to variations in the chemistry of carbonatitic fluids and, consequently, their ability to mobilize specific trace elements from earlier-crystallized minerals. An important telltale indicator of hydrothermal reworking is deviation from the primary, chondrite-like REE ratios (in particular, Y/Ho and Eu/Eu*), accompanied by a variety of other compositional changes depending on the redox state of the fluid (e.g., depletion of carbonates in Mn owing to its oxidation and sequestration by secondary oxides). The effect of supergene processes was studied on a single sample from Bear Lodge, which shows extreme depletion in Mn and Ce (both due to oxidation), coupled with enrichment in Pb and U, possibly reflecting an increased availability of Pb2+ and (UO2)2+ species in the system. On the basis of these findings, several avenues for future research can be outlined: (1) structural mechanisms of REE uptake by carbonates; (2) partitioning of REE and LILE between cogenetic calcite and dolomite; (3) the effects of fluorapatite, phlogopite and pyrochlore fractionation on the LILE budget of magmatic carbonates; (4) the cause(s) of coupled Mn-Ce depletion in some primary calcite; and (5) relations between fluid chemistry and compositional changes in hydrothermal carbonates.
DS201702-0201
2017
Yang, P.Chakhmouradian, A.R., Rehuir, E.P., Zaitsev, A.N., Coueslan, C., Xu, C., Kynicky, J., Hamid Mumin, A., Yang, P.Apatite in carbonatitic rocks: compositional variation, zoning, element partitioning and petrogeneitic significance.Lithos, in press available, 138p.TechnologyCarbonatite

Abstract: The Late Cretaceous (ca. 100 Ma) diamondiferous Fort à la Corne (FALC) kimberlite field in the Saskatchewan (Sask) craton, Canada, is one of the largest known kimberlite fields on Earth comprising essentially pyroclastic kimberlites. Despite its discovery more than two decades ago, petrological, geochemical and petrogenetic aspects of the kimberlites in this field are largely unknown. We present here the first detailed petrological and geochemical data combined with reconnaissance Nd isotope data on drill-hole samples of five major kimberlite bodies. Petrography of the studied samples reveals that they are loosely packed, clast-supported and variably sorted, and characterised by the presence of juvenile lapilli, crystals of olivine, xenocrystal garnet (peridotitic as well as eclogitic paragenesis) and Mg-ilmenite. Interclast material is made of serpentine, phlogopite, spinel, carbonate, perovskite and rutile. The mineral compositions, whole-rock geochemistry and Nd isotopic composition (Nd: + 0.62 to ? 0.37) are indistinguishable from those known from archetypal hypabyssal kimberlites. Appreciably lower bulk-rock CaO (mostly < 5 wt%) and higher La/Sm ratios (12-15; resembling those of orangeites) are a characteristic feature of these rocks. Their geochemical composition excludes any effects of significant crustal and mantle contamination/assimilation. The fractionation trends displayed suggest a primary kimberlite melt composition indistinguishable from global estimates of primary kimberlite melt, and highlight the dominance of a kimberlite magma component in the pyroclastic variants. The lack of Nb-Ta-Ti anomalies precludes any significant role of subduction-related melts/fluids in the metasomatism of the FALC kimberlite mantle source region. Their incompatible trace elements (e.g., Nb/U) have OIB-type affinities whereas the Nd isotope composition indicates a near-chondritic to slightly depleted Nd isotope composition. The Neoproterozoic (~ 0.6-0.7 Ga) depleted mantle (TDM) Nd model ages coincide with the emplacement age (ca. 673 Ma) of the Amon kimberlite sills (Baffin Island, Rae craton, Canada) and have been related to upwelling protokimberlite melts during the break-up of the Rodinia supercontinent and its separation from Laurentia (North American cratonic shield). REE inversion modelling for the FALC kimberlites as well as for the Jericho (ca. 173 Ma) and Snap Lake (ca. 537 Ma) kimberlites from the neighbouring Slave craton, Canada, indicate all of their source regions to have been extensively depleted (~ 24%) before being subjected to metasomatic enrichment (1.3-2.2%) and subsequent small-degree partial melting. These findings are similar to those previously obtained on Mesozoic kimberlites (Kaapvaal craton, southern Africa) and Mesoproterozoic kimberlites (Dharwar craton, southern India). The striking similarity in the genesis of kimberlites emplaced over broad geological time and across different supercontinents of Laurentia, Gondwanaland and Rodinia, highlights the dominant petrogenetic role of the sub-continental lithosphere. The emplacement of the FALC kimberlites can be explained both by the extensive subduction system in western North America that was established at ca. 150 Ma as well as by far-field effects of the opening of the North Atlantic ocean during the Late Cretaceous.
DS201801-0053
2017
Yang, P.Reguir, E.P., Chakhmouradian, A.R., Zaitsev, A.N., Yang, P.Trace element variations and zoning in phlogopite from carbonatites and phoscorites.Carbonatite-alkaline rocks and associated mineral deposits , Dec. 8-11, abstract p. 8-9.carbonatites

Abstract: Phlogopite from carbonatites and phoscorites worldwide shows three major types of core-to-rim trends of compositional variation: Ba+Al-, Fe and Fe+Al enrichment. These major-element trends are accompanied by largely consistent changes in traceelement abundances. Uptake of Rb, Sr, Ba, Sc, V, Mn and HFSE by phlogopite is susceptible to changes in the availability of these elements due to precipitation of other early silicate and oxide phases (especially, magnetite, apatite and niobates). In rare cases, more complex oscillatory and sector patterns are juxtaposed over the principal evolutionary trend, indicating kinetic and crystal-chemical controls over element uptake. Phlogopite is a common accessory to major constituent of carbonatites and genetically related rocks (including phoscorites). Major-element variations of phlogopite from these rocks have been addressed in much detail in the literature (for references, see Reguir et al. 2009), whereas its trace-element characteristics and zoning patterns have so far received little attention. In this work, we examined the compositional variation of phlogopite from 23 carbonatite and phoscorite localities worldwide. The major-element compositions were determined using wavelength-dispersive X-ray spectrometry (WDS) and trace-element abundances by laser-ablation inductively-coupled-plasma mass-spectrometry (LA-ICPMS). Previously, two major core-to-rim zoning trends have been identified in micas from calcite carbonatites (Reguir et al. 2009, 2010). Phlogopite from Oka (Canada) and Iron Hill (USA), for example, involves an increase in kinoshitalite component rim-ward, accompanied by enrichment in high-field-strength elements (HFSE = Zr, Nb, Ta), Sr and Sc. At most other carbonatite localities (e.g., Kovdor in Russia, or Prairie Lake in Canada), phlogopite crystals exhibit rim-ward enrichment in Fe. In the present work, we confirmed these two common types of zoning, and identified new patterns that have not been reported in the previous literature. In addition to the common Fe-enrichment trend, which occurs in both carbonatites (e.g., Guli in Russia and Sokli in Finland) and phoscorites (e.g., Aley in Canada), we identified a Fe-Al-enrichment subtype of this zoning pattern observed, for example, in samples from the Shiaxiondong calcite carbonatite (China). Overall, the Fe-enrichment pattern is accompanied by rim-ward depletion in Ba, Rb and HFSE, coupled with enrichment in Mn. Other trace elements exhibit no consistent variation among the studied samples. The Shiaxiondong material is characterized by the highest recorded Rb values, ranging from 1120 to 660 ppm. Phlogopite from the Kovdor calcite-forsterite-magnetite phoscorite contains the highest recorded levels of Nb and Ta, ranging from 320 ppm and 40 ppm, respectively, in the core to 85 ppm and 4 ppm in the rim. The maximum levels of Zr (up to 50 ppm) were observed in the core of Prairie Lake phlogopite, whereas its rim contains the highest measured Mn content (up to 4100 ppm). The levels of Sc are typically below 100 ppm in samples from calcite and dolomite carbonatites, but may reach 280 ppm in phoscorites. Interestingly, phlogopite from phoscorites shows rim-ward enrichment in Sc, whereas the opposite trend is observed in carbonatitic micas. Phlogopite from calcite carbonatites at Zibo (China) and Valentine Township (Canada), and from phoscorites at Aley (Canada) shows an unusual zoning pattern involving depletion in Fe, which is accompanied by a decrease in Al, Ba, Sr, Zr, Hf, Y, Sc and V abundances. The concentrations of other trace elements, including Nb and Ta show inconsistent variations. In the Aley phoscorite, phlogopite is enriched in Ba (up to 15000 ppm in the core and < 7500 ppm in the rim), but poor in Sr (80 and 35 ppm in the core and rim, respectively) relative to those from the Zibo and Valentine carbonatites. Zirconium levels reach 200 and 170 ppm in the core, and drop to < 40 and 60 ppm in the rim of the Valentine and Zibo samples, respectively. In the Aley sample, the content of Zr does not exceed 55 ppm. The Zibo sample is also enriched in V (up to 230 and 160 ppm in the core and rim, respectively) relative to the two other samples (< 100 ppm V). The Sc and Hf levels are consistently low (less than 30 and 4 ppm, respectively). In addition to simple core-rim patterns, phlogopite from carbonatites and phoscorites may exhibit oscillatory zoning, which involves periodic variations in Fe/Mg ratio. Iron-rich zones are relatively depleted in Mn, but enriched in Nb. One sample of phoscoritic phlogopite (Aley) exhibits striking sector zoning juxtaposed over the overall Feenrichment trend and Fe-Mg oscillations. In terms of major elements, basal sectors perpendicular to [001] are enriched in Fe and Al, but depleted in Mg and K relative to the flank sectors. This enrichment is accompanied by higher Ba, Sr and HFSE levels in the basal sector. Our data confirm that there is no universal pattern of zoning in carbonatitic or phoscoritic phlogopite, and variations in the content of most trace elements are strongly coupled to major-element patterns. Three major core-to-rim variation trends, as well as juxtaposed oscillatory and sector patterns, can be recognized. The observed compositional variations indicate that, in the majority of cases, the trace-element composition of phlogopite is controlled by partitioning of Rb, Sr, Ba, Sc, V, Mn and HFSE between this mineral, its parental magma, and co-precipitating early phases. Among the latter, magnetite, apatite and niobates appear to exert the greatest influence on element distributions. More complex oscillatory and sector patterns imply the presence of kinetic and crystal-chemical controls over element uptake in certain carbonatitic systems
DS202109-1487
2021
Yang, P.Reguir, E.P., Salinkova, E.B., Yang, P., Chakmouradian, A.R., Stifeeva, M.V., Rass, I.T., Kotov, A.B.U-Pb geochronology of calcite carbonatites and jacupirangite from the Guli alkaline complex, Polar Siberia, Russia.Mineralogical Magazine, Vol. 85, 4, pp. 469-483.Russia, Siberiadeposit - Guli

Abstract: Mantle xenoliths from the Middle-Late Jurassic Obnazhennaya kimberlite are often compared with those from the Udachnaya kimberlite (ca. 367 Ma) to inform the evolution of the Siberia craton. However, there are no direct constraints on the timing of the Obnazhennaya kimberlite eruption. Such uncertainty of the kimberlite age precludes a better understanding of the mantle xenoliths from the Obnazhennaya pipe, and thus also of the evolution of the Siberia craton. This paper reports U-Pb ages for both perovskite from the Obnazhennaya kimberlite and rutile in an Obnazhennaya eclogite xenolith. The fresh perovskite formed during the early stage of magmatic crystallization and yields a U-Pb age of 151.8 ± 2.5 Ma (2?). Rutile in the eclogite xenolith yields an overlapping U-Pb age of 154.2 ± 1.9 Ma (2?). Because rutile has a Pb closure temperature lower than the inferred residence temperature of the eclogite prior to eruption, the U-Pb isotope system in rutile was not closed until the host eclogite was entrained and delivered to the surface by the kimberlite and therefore records the timing of kimberlite eruption. These data provide the first direct constraints on the emplacement age of the Obnazhennaya kimberlite and add to the global ‘kimberlite bloom’ from ca. 250-50 Ma as well as to the largest pulse of kimberlite volcanism in Siberia from ca. 171-144 Ma. The timing of this Jurassic-Cretaceous pulse coincides with the closure of the Mongol-Okhotsk Ocean, but the depleted Sr-Nd isotopic characteristics of 171-144 Ma kimberlites are inconsistent with a subduction-driven model for their petrogenesis. Thus, the closure of the Mongol-Okhotsk Ocean may act as a trigger for the initiation of 171-144 Ma kimberlite emplacement of Siberia, but was not the source.
DS201012-0295
2010
Yang, Q.Huang, X., Niu, Y., Xu, Y-G., Chen, L-L., Yang, Q.Mineralogical and geochemical constraints on the preogenesis of post collisional potassic and ultrpotassic rocks from Western Yunnan, SW China.Journal of Petrology, Vol. 51, 8, pp. 1617-1654.ChinaAlkalic
DS201909-2106
2019
Yang, Q.Wang, T., Gao, S.S., Dai, Y., Yang, Q., Liu, K.H.Lithospheric structure and evolution of southern Africa: constraints from joint inversion of Rayleigh wave dispersion and receiver functions.Geochemistry, Geophysics, Geosystems, Vol. 20, 7, pp. 3311-3327.Africa, South Africageophysics

Abstract: We conduct a joint inversion of teleseismic receiver functions and Rayleigh wave phase velocity dispersion from both ambient noise and earthquakes using data from 79 seismic stations in southern Africa, which is home to some of the world's oldest cratons and orogenic belts. The area has experienced two of the largest igneous activities in the world (the Okavango dyke swarm and Bushveld mafic intrusion) and thus is an ideal locale for investigating continental formation and evolution. The resulting 3?D shear wave velocities for the depth range of 0-100 km and crustal thickness measurements show a clear spatial correspondence with known geological features observed on the surface. Higher than normal mantle velocities found beneath the southern part of the Kaapvaal craton are consistent with the basalt removal model for the formation of cratonic lithosphere. In contrast, the Bushveld complex situated within the northern part of the craton is characterized by a thicker crust and higher crustal Vp/Vs but lower mantle velocities, which are indicative of crustal underplating of mafic materials and lithospheric refertilization by the world's largest layered mafic igneous intrusion. The thickened crust and relatively low elevation observed in the Limpopo belt, which is a late Archean collisional zone between the Kaapvaal and Zimbabwe cratons, can be explained by eclogitization of the basaltic lower crust. The study also finds evidence for the presence of a stalled segment of oceanic lithosphere beneath the southern margin of the Proterozoic Namaqua?Natal mobile belt.
DS202008-1401
2020
Yang, S.Huang, S., Tschauner, O., Yang, S., Humayun, M.HIMU signature trapped in a diamond from the mantle transition zone.Goldschmidt 2020, 1p. AbstractMantlediamond inclusion

Abstract: Mantle plumes sample the deep mantle. A limited number of geochemical endmember components can describe the isotopic and compositional variations in the ocean island basalts (OIBs), which are produced by plume volcanism. The endmembers are correlated to compositions in the OIB source regions or represent incorporation of material upon ascent. However, their actual nature and origins are still highly debated. The depths of plume sources have been proposed to be anywhere between the core-mantle boundary and the upper mantle, and need not be the same for all plume-related volcanic activities. Using a combination of synchrotron micro-X ray fluorescence and -diffraction mapping, and in-situ Laser Ablation Inductively Coupled Plasma Mass Spectrometry, we show that the elemental features of HIMU-rich OIBs, such as Bermuda, St Helena, and Cook-Austral, exactly match the geochemical signature of a multiphase inclusion in a diamond. The geochemical signature in our studied diamond inclusion is markedly different from that of inclusions in lithospheric diamonds. The phases identified in the inclusion are majorite-rich garnet, ilmenite, the sodic 10Å-phase (TAP), and liebermannite. Furthermore, we show that this inclusion was entrapped at 14.5 ± 0.5 GPa (420-440 km) and 1450 ± 50 K. At the conditions of entrapment, the diamond inclusion phase assembly was garnet + ilmenite + liebermannite + clinopyroxene + stishovite + fluid. Sodic TAP is a retrograde product of reaction between clinopyroxene, stishovite, and fluid upon ascent. Its presence shows that the HIMU source is water-saturated. Entrapment in diamond indicates that the fluid also contained carbonate. The conditions of 14.5 ± 0.5 GPa and 1450 ± 50 K plot right on top of the alkaline carbonatite solidus, and match the formation of carbonatitic melt from subducted slabs plus diamond formation from reaction of carbonate with iron. In summary, our data show that the transition zone source accounts for the global HIMU endmember.
DS202008-1459
2020
Yang, S.Yang, S., Humayaun, M., Salters, V.J.M.Elemental constrains on the amount of recycled crust in the generation of mid-ocean basalts.Science Advances, https://phys.org/ news/2020-06- geochemists- mystery-earth-crust .htmlMantlegeochemistry

Abstract: Mid-oceanic ridge basalts (MORBs) are depleted in incompatible elements, but ridge segments far from mantle plumes frequently erupt chemically enriched MORBs (E-MORBs). Two major explanations of E-MORBs are that these basalts are generated by the melting of entrained recycled crust (pyroxenite) beneath ridges or by the melting of refertilized peridotites. These two hypotheses can be discriminated with compatible element abundances from Sc to Ge, here termed the ScGe elements. Here, we demonstrate that E-MORBs have systematically lower Ge/Si and Sc contents and slightly higher Fe/Mn and Nb/Ta ratios than depleted MORBs (D-MORBs) due to the mixing of low-degree pyroxenite melts. The Ge/Si ratio is a new tracer that effectively discriminates between melts derived from peridotite sources and melts derived from mixed pyroxenite-peridotite sources. These new data are used to estimate the distribution of pyroxenite in the mantle sources of global MORB segments.
DS202112-1952
2021
Yang, S.Tschauner, O., Huang, S., Yang, S., Humayun, M., Liu, W., Gilbert Corder, S.N., Bechtel, H.A., Tischler, J., Rossman, G.R.Nature discovery of davemaoite, CaSiO3-perovskite, as a mineral from the lower mantle. Science, Vol. 374, 6569, pp. 891-894. pdfMantlemineralogy

Abstract: Calcium silicate perovskite, CaSiO3, is arguably the most geochemically important phase in the lower mantle, because it concentrates elements that are incompatible in the upper mantle, including the heat-generating elements thorium and uranium, which have half-lives longer than the geologic history of Earth. We report CaSiO3-perovskite as an approved mineral (IMA2020-012a) with the name davemaoite. The natural specimen of davemaoite proves the existence of compositional heterogeneity within the lower mantle. Our observations indicate that davemaoite also hosts potassium in addition to uranium and thorium in its structure. Hence, the regional and global abundances of davemaoite influence the heat budget of the deep mantle, where the mineral is thermodynamically stable.
DS201212-0824
2013
Yang, S-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
DS201412-0960
2014
Yang, S-H.Wang, H., Wu, Y-B., Gao, S., Zheng, J-P., Liu, Q., Liu, X-C., Qin, Z-W., Yang, S-H., Gong, H-J.Deep subduction of continental crust in accretionary orogen: evidence from U-Pb dating on diamond-bearing zircons from the Qinling orogen, central China.Lithos, Vol. 190-191, pp. 420-429.ChinaUHP
DS200512-1213
2005
Yang, T.Yang, T., Shen, Y.P wave velocity structure of the crust and uppermost mantle beneath Iceland from local earthquake tomography.Earth and Planetary Science Letters, Advanced in press,Europe, IcelandMantle tomography, hot spot, plume
DS200612-1564
2006
Yang, T.Yang, T., Shen, Y., Van der lee, S., Solomon, S.C., Hung, S.H.Upper mantle structure beneath the Azores hotspot from finite frequency seismic tomography.Earth and Planetary Science Letters, Vol. 250, 1-2, pp. 11-26.AzoresGeophysics - seismics
DS200912-0446
2009
Yang, T.Liu, Q., Yang, T., Zeng, Q., Zheng, J., Luo, Y., Qui, N., Xu, H., Jin, Z.Magnetic study of the UHP eclogites from the Chinese Continental Scientific drilling project.Journal of Geophysical Research, Vol. 114, B02106.ChinaUHP
DS201012-0454
2010
Yang, T.Liu, Q., Zeng, Q., Zheng, J., Yang, T., Qui, N., Liu, Z., Lou, Y., Jin, Z.Magnetic properties of serpentinized garnet peridotites from the CCSD main hole in the Sulu ultrahigh pressure metamorphic belt, eastern China.Journal of Geophysical Research, Vol. 115, B6, B06104ChinaUHP
DS201412-1003
2014
Yang, T.Yang, T., Leng, W.Dynamics of hidden hotspot tracks beneath the continental lithosphere.Earth and Planetary Science Letters, Vol. 401 pp. 294-300.MantlePlume
DS201803-0485
2018
Yang, T.Wang, D., Wang, X-L., Cai, Y., Goldstein, S.L., Yang, T.Do Hf isotopes in magmatic zircons represent those of their host rocks?Journal of Asian Earth Sciences, Vol. 154, pp. 202-212.Mantlezircons

Abstract: Lu-Hf isotopic system in zircon is a powerful and widely used geochemical tracer in studying petrogenesis of magmatic rocks and crustal evolution, assuming that zircon Hf isotopes can represent initial Hf isotopes of their parental whole rock. However, this assumption may not always be valid. Disequilibrium partial melting of continental crust would preferentially melt out non-zircon minerals with high time-integrated Lu/Hf ratios and generate partial melts with Hf isotope compositions that are more radiogenic than those of its magma source. Dissolution experiments (with hotplate, bomb and sintering procedures) of zircon-bearing samples demonstrate this disequilibrium effect where partial dissolution yielded variable and more radiogenic Hf isotope compositions than fully dissolved samples. A case study from the Neoproterozoic Jiuling batholith in southern China shows that about half of the investigated samples show decoupled Hf isotopes between zircons and the bulk rocks. This decoupling could reflect complex and prolonged magmatic processes, such as crustal assimilation, magma mixing, and disequilibrium melting, which are consistent with the wide temperature spectrum from ?630?°C to ?900?°C by Ti-in-zircon thermometer. We suggest that magmatic zircons may only record the Hf isotopic composition of their surrounding melt during crystallization and it is uncertain whether their Hf isotopic compositions can represent the primary Hf isotopic compositions of the bulk magmas. In this regard, using zircon Hf isotopic compositions to trace crustal evolution may be biased since most of these could be originally from disequilibrium partial melts.
DS201906-1327
2019
Yang, T.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
Yang, T.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.
DS202108-1278
2021
Yang, T.Ding, J., Zhang, S., Evans, D.A.D., Yang, T., Li, H.North China craton: the conjugate margin for northwestern Laurentia in Rodinia.Geology, Vol. 49, March pp. 773-778.ChinaRodinia

Abstract: In the Rodinia supercontinent, Laurentia is placed at the center because it was flanked by late Neoproterozoic rifted margins; however, the conjugate margin for western Laurentia is still enigmatic. In this study, new paleomagnetic results have been obtained from 15 ca. 775 Ma mafic dikes in eastern Hebei Province, North China craton (NCC). Stepwise thermal demagnetization revealed a high-temperature component, directed northeast or southwest with shallow inclinations, with unblocking temperatures of as high as 580 °C. Rock magnetism suggests the component is carried by single-domain and pseudo-single-domain magnetite grains. Its primary origin is supported by a positive reversal test and regional remanence direction correlation test, and the paleomagnetic pole (29.0°S, 64.7°E, A95 = 5.4°) is not similar to any published younger poles of the NCC. Matching the late Mesoproterozoic to early Neoproterozoic (ca. 1110-775 Ma) apparent polar wander paths of the NCC and Laurentia suggests that the NCC could have been the conjugate margin for northwestern Laurentia in Rodinia, rather than sitting off the northeast coast of the main Rodinian landmass. Geological data indicate that breakup of the NCC and Laurentia occurred between ca. 775 and 720 Ma.
DS200512-1214
2005
Yang, T.N.Yang, T.N., Zeng, L., Liou, J.G.Mineral evolution of a garnet pyroxenite nodule within eclogite, eastern Sulu ultrahigh-pressure metamorphic terrane, east China.Journal of Metamorphic Geology, Vol. 23, 8, pp. 667-680.ChinaUHP
DS200612-0788
2006
Yang, T.N.Leech, M.L., Webb, L.E., Yang, T.N.Diachronous histories for the Dabie Sulu orogen from high temperature geochronology.Geological Society of America, Special Paper, No. 403, pp. 1-22.ChinaUHP
DS200612-1515
2006
Yang, T.N.Webb, L.E., Leech, M.L., Yang, T.N.49 Ar 39 Ar thermochronology of the Sulu terrane: Late Triassic exhumation of high and ultrahigh pressure rocks -implications for Mesozoic tectonics East Asia.Geological Society of America, Special Paper, No. 403, pp. 77-92.ChinaUHP
DS200612-1516
2006
Yang, T.N.Webb, L.E., Leech, M.L., Yang, T.N.40 Ar 39 Ar thermochronology of the Sulu terrane: Late Triassic exhumation of high and UHP rocks and implications for Mesozoic tectonics in East Asia.Geological Society of America Special Paper, No. 403, pp. 77-92.ChinaUHP - Sulu, Dabie, geothermometry
DS200812-1293
2008
Yang, T.N.Yang, T.N., Zeng, L., Zhao, Z.R., Liou, J.G.Retrograde reaction of an ultrahigh pressure metamorphic spinel pyroxenite lens, northeast Sulu UHP terrane, eastern China.International Geology Review, Vol. 50, 1, pp. 32-47.ChinaUHP
DS1999-0780
1999
Yang, W.Wang, X., Neubauer, F., Genser, J., Yang, W.The Dabie ultra high pressure (UHP) unit, Central China: a Cretaceous extensional allochthon superposed on a Triassic Orogen.Terra Nova, Vol. 10, No. 5, p. 260-67.ChinaTectonics, metamorphism, Dabie
DS2003-1521
2003
Yang, W.Yang, W.Flat mantle reflectors in eastern China: possible evidence for lithospheric thinningTectonophysics, Vol. 369, 3-4, July pp. 219-30.ChinaGeophysics - seismics, Heterogeneity
DS200412-2172
2003
Yang, W.Yang, W.Flat mantle reflectors in eastern China: possible evidence for lithospheric thinning.Tectonophysics, Vol. 369, 3-4, July pp. 219-30.ChinaGeophysics - seismics Heterogeneity
DS200912-0833
2009
Yang, W.Yang, W., Teng, F-Z., Zhang, H-F.Chondritic magnesium isotopic composition of the terrestrial mantle: a case study of peridotite xenoliths from the North Chin a craton.Earth and Planetary Science Letters, Vol. 288, 3-4, pp. 475-481.ChinaGeochronology
DS201112-0612
2011
Yang, W.Liu, S-A., Teng, F-Z., Yang, W., Wu, F-Y.High temperature inter-mineral magnesium isotope fractionation in mantle xenoliths from the North Chin a craton.Earth and Planetary Science Letters, Vol. 308, 1-2, pp. 131-140.ChinaGeochronology UHP
DS201312-0539
2013
Yang, W.Liang, Q., Meng, Y., Yan, C., Krasnicki, S., Lai, J., Hemawan, K., Shu,H., Popov, D., Yu,T., Yang, W., Mao, H., Hemley, R.Developments in synthesis, characterization, and application of large high-quality CVD single crystal diamond.Journal of Superhard Materials, Vol. 35, 4, pp. 195-213.TechnologyDiamond synthetics
DS201312-0908
2013
Yang, W.Teng, F-Z., Yang, W., Rudnick, R., Hu, Y.Heterogeneous magnesium isotopic composition of the lower continental crust: a xenolith perspective.Geochemistry, Geophysics, Geosystems: G3, Vol. 14, 9, pp. 3844-3856.MantleXenoliths
DS201412-1024
2014
Yang, W.Zhang, L., Meng, Y., Yang, W.,Wang, L., Mao, W.L., Zeng, Q-S., Jeong, J.S., Wagner, A.J., Mkhoyan, K.A., Liu, W., Xu, R., Mao, H-K.Disproportionation of (Mg,Fe) SiO3 perovskite in Earth's deep lower mantle.Science, Vol. 344, no. 6186, pp. 877-882.MantlePerovskite
DS201603-0432
2016
Yang, W.Yang, W., Teng, F-Z., Li, W-Y., Liu, S-A., Ke, S., Liu, Y-S., Zhang, H-F., Gao, S.Magnesium isotopic composition of the deep continental crust.American Mineralogist, Vol. 101, pp. 243-252.MantleMineralogy
DS201703-0410
2017
Yang, W.Jia, X., Wang, X., Yang, W.Petrogenesis and geodynamic implications of the Early Paleozoic potassic and ultrapotassic rocks in the south Chin a block.Journal of Asian Earth Sciences, Vol. 135, pp. 80-94.ChinaAlkaline rocks

Abstract: In this paper, some potassic and ultrapotassic rocks in the South China Block (SCB) have been recognized, according to a set of new geochronological, geochemical and Sr-Nd isotopic data. Zircon U-Pb dating from six plutons yield consistent crystallization ages of 445-424 Ma. These potassic and ultrapotassic rocks can be geochemically subdivided into three groups. Group 1, represented by the Longchuan gabbro, longmu diabase, Tangshang and Danqian diorite (445-433 Ma), have low silica contents (SiO2 = 47.38-54.16 wt.%), and high MgO (4.21-9.51 wt.%) and total alkalis (Na2O + K2O = 3.08-5.57 wt.%), with K2O/Na2O ratios of 0.62-1.82. They are enriched in LREE and depleted in Ba, Sr and Ta-Nb-Ti, and exhibit relatively high initial 87Sr/86Sr ratios (0.70561-0.71128), low ?Nd(430 Ma) values (?8.4 to ?3.2), suggesting that they were most plausibly generated by the partial metling of enriched mantle source (EMI). Group 2, from the Huwei diorite (424 Ma), have 45.68-52.87 wt.% of SiO2, 5.79-9.25 wt.% of MgO and 52-65 of mg-number. They have significantly higher Th (9.92 ppm), Ce (88.0-115 ppm) concentration and Ce/Yb (27.6-46.8), Th/Yb ratios (2.58-7.99), and relatively low initial 87Sr/86Sr ratios (0.70501-0.70599), and high ?Nd(430 Ma) values (?2.1 to ?1.5). We propose that they originated from the partial melting of the depleted mantle source with subsequent contamination by crustal materials. Group 3, represented by the Daning lamprophyre (?445 Ma), has SiO2 contents ranging from 41.73 wt.% to 45.22 wt.%, MgO from 13.74 wt.% to 15.16 wt.%, and mg-muber from 73 to 77, with high K2O/Na2O ratios (>2.0). They have 87Sr/86Sr ratios of 0.62912-0.70384 and ?Nd(t = 430 Ma) values of ?6.4 to ?6.3, indicating that the source components are close to the EMI source, with significant sediments involved. These Silurian potassic and ultrapotassic rocks in the SCB can be responsible for post-orogenic delamination and intra-plate extension. And the delamination had a small size and a long duration, and a negligible impact.
DS2002-0781
2002
Yang, W.Z.Jiang, Y.R., Jiang, S.Y., Ling, H.F., Zhou, X.R., Rui, X.J., Yang, W.Z.Petrology and geochemistry of shoshonitic plutons from the western Kunlun OrogenLithos, Vol.63,3-4, pp. 165-187.ChinaShoshonites
DS202205-0734
2022
Yang, W-B.Yang, W-B., Niu, H-C., Li, N-B., Hollings, P., Zurevinski, S., Mitchell, R.H.Scavenging and release of REE and HFSE by alkali amphiboles during Na-metasomatism in magmatic-hydrothermal systems.Fundamental Research , 10.1016/j.fmre.2022.04.004 34p. PdfMantleREE

Abstract: Exploitable or potentially exploitable deposits of critical metals, such as rare-earth (REE) and high-field-strength elements (HFSE), are commonly associated with alkaline or peralkaline igneous rocks. However, the origin, transport and concentration of these metals in peralkaline systems remains poorly understood. This study presents the results of a mineralogical and geochemical investigation of the Na-metasomatism of alkali amphiboles from a barren peralkaline granite pluton in NE China, to assess the remobilization and redistribution of REE and HFSE during magmatic-hydrothermal evolution. Alkali amphiboles from the peralkaline granites show evolutionary trends from calcic through sodic-calcic to sodic compositions, with increasing REE and HFSE concentrations as a function of increasing Na-index (Na#, defined as molar Na/(Na+Ca) ratios). The Na-amphiboles (i.e., arfvedsonite) can be subsequently altered, or breakdown, to form Na-clinopyroxene (i.e., aegirine) during late- or post-magmatic alteration. Representative compositions analyzed by in-situ LA-ICPMS show that the alkali amphiboles have high and variable REE (1295-2218 ppm) and HFSE (4194-16,862 ppm) contents, suggesting that these critical metals can be scavenged by alkali amphiboles. Compared to amphiboles, the early replacement aegirine (Aeg-I, Na#?=?0.91-0.94) has notably lower REE (577-797) and HFSE (4351-5621) contents. In contrast, the late hydrothermal aegirine (Aeg-II, Na#?=?0.92-0.96) has significantly lower REE (127-205 ppm) and HFSE (6.43-72.2 ppm) contents. Given that the increasing Na# from alkali amphibole to aegirine likely resulted from Na-metasomatism, a scavenging-release model can explain the remobilization of REE and HFSE in peralkaline granitic systems. The scavenging and release of REE and HFSE by alkali amphiboles during Na-metasomatism provides key insights into the genesis of globally significant REE and HFSE deposits. The Na-index of alkali amphibole-aegirine might be useful as a geochemical indicator in the exploration for these critical-metals.
DS1983-0638
1983
Yang, X.Yang, X.Microstructure and Stress Estimation of Minerals in Lherzolite Residual Fragments.Acta Geol. Sinica., Vol. 57, No. 4, PP. 391-400.ChinaBlank
DS201312-0528
2013
Yang, X.Lai, X., Yang, X.Geochemical characteristics of the Bayan Obo giant REE Nb Fe deposit: constraints on its genesis.Journal of South American Earth Sciences, Vol. 41, pp. 99-112.ChinaDeposit - Bayan Obo
DS201512-1995
2015
Yang, X.Yang, X.OH solubility in olivine in the peridotote-COH system under reducing conditions and implications for water storage and hydrous melting in the reducing upper mantle.Earth and Planetary Science Letters, Vol. 432, pp. 199-209.MantleMelting

Abstract: Experimental studies of OH solubility in peridotite minerals are of crucial importance for understanding some key geochemical, geophysical and geodynamical properties of the upper mantle. In reducing depths of the upper mantle, C-O-H fluids are dominated by CH4 and H2O. However, available experimental H-annealing of olivine concerning water storage capacity in the reducing upper mantle has been exclusively carried out by equilibrating olivine with H2O only. In this study, OH solubility in olivine has been investigated by annealing natural olivine crystals under peridotite-bearing and CH4-H2O-present conditions with piston cylinder and multi-anvil apparatus. Experiments were performed at 1-7 GPa and 1100-1350?°C and with oxygen fugacity controlled by Fe-FeO buffer, and OH solubilities were measured from polarized infrared spectra. The olivines show no change in chemical composition during the experiments. The infrared spectra of all the annealed olivines show OH bands in the range 3650-3000 cm?1, at both high (>3450 cm?1) and low (<3450 cm?1) frequency, and the bands at ?3400-3300 cm?1 are greatly enhanced above ?3 GPa and 1300?°C. The determined H2O solubility is ?90-385 ppm for the olivine coexisting with H2O (1-7 GPa and 1100?°C), and is ?40-380 ppm for the olivine coexisting with CH4-H2O (1-7 GPa and 1100-1350?°C). When CH4 is present in the equilibrium fluid, the H2O solubility is reduced by a factor of ?2.3 under otherwise identical conditions, indicating a strong effect of CH4 on the partitioning of water between olivine and coexisting fluid. The storage capacity of water in the reducing upper mantle is, modeled with the measured solubility of olivine and available partition coefficients of water between coexisting minerals, up to ?2 orders of magnitude lower than some previous estimates. Considering the temperature along the geotherm in the reducing oceanic upper mantle, the required H2O concentration to trigger hydrous melting is 250 and 535 ppm at ?100 and 210 km depth, respectively, and is even larger at greater depths. These values exceed the typical H2O abundance (?100±50 ppm?100±50 ppm) in the upper mantle, suggesting that pervasive hydrous melting at reducing depths of the oceanic upper mantle is not likely. Similar arguments may also be casted for the reducing deep upper mantle in the continental regions.
DS201512-1996
2015
Yang, X.Yang, X., Williams, M.Landforms and processes in arid and semi-arid environments.Catena, Vol. 134, pp. 4-13.Africa, South Africa, AustraliaGeomorphology
DS201702-0256
2017
Yang, X.Yang, X., Lai, X., Pirajno, F., Liu, Y., Mingxing, L., Sun, W.Genesis of the Bayan Obo Fe_REE-Nb formation in Inner Mongolia, North Chin a craton: a perspective review.Precambrian Research, Vol. 288, pp. 39-71.ChinaDeposit - Bayan Obo

Abstract: The Bayan Obo deposit in Inner Mongolia, North China Craton (NCC) is the largest rare-earth element (REE) resource in the world. Due to the complex element and mineral compositions and the activity of several geological events, the ore-forming mechanism is still controversial. Previous models are reviewed here to provide information for further investigation on the Bayan Obo deposit. In this study, we summarize all different types of Fe-REE-Nb mineralization using field observations and microscope work, in which we recognize 9 types of Fe-REE-Nb ores in the Bayan Obo ore district. By compiling and re-evaluating a large number of published geochemical data, this paper provides solid evidence that the Bayan Obo deposit formed through interaction between sedimentary rocks and carbonatite magmatism. From the results of our review, it can be conjectured that the formation of iron ores was originated from sedimentation (Pt1), whereas the formation of REE mineralized dolomite might be related to interaction and reaction between the carbonatite magmas and/or associated fluids with sedimentary carbonate rocks, with the REE-bearing carbonatite magmas having undergone intense fractionation enrichment process. The C-O-S-Fe-Mg isotopes indicate that the REE-Nb mineralization was derived from metasomatism (fenitic alteration) of sedimentary carbonate. A new model is proposed for this unique REE-Nb mineralization, which is related to the subduction of Siberian Craton beneath the North China Craton since Early Paleozoic period. We interpret that the Bayan Obo Fe-REE-Nb ore deposits and their massive barren host, H8 dolomite, were generated as a result of interaction of fluids expelled from a subcontinental lithospheric mantle (SCLM)-derived carbonatite magma with sedimentary carbonates.
DS201706-1095
2017
Yang, X.Marshak, S., Domrois, S., Abert, C., Larson, T., Pavlis, G., Hamburger, M., Yang, X., Gilbert, H., Chen, C.The basement revealed: tectonic insight from a digital elevation model of the Great Unconformity, USA cratonic platform.Geology, Vol. 45, 5, pp. 391-394.United Statestectonics - Mid continent

Abstract: Across much of North America, the contact between Precambrian basement and Paleozoic strata is the Great Unconformity, a surface that represents a >0.4 b.y.-long hiatus. A digital elevation model (DEM) of this surface visually highlights regional-scale variability in the character of basement topography across the United States cratonic platform. Specifically, it delineates Phanerozoic tectonic domains, each characterized by a distinct structural wavelength (horizontal distance between adjacent highs) and/or structural amplitude (vertical distance between adjacent lows and highs). The largest domain, the Midcontinent domain, includes long-wavelength epeirogenic basins and domes, as well as fault-controlled steps. The pronounced change in land-surface elevation at the Rocky Mountain Front coincides with the western edge of the Midcontinent domain on the basement DEM. In the Rocky Mountain and Colorado Plateau domains, west of the Rocky Mountain Front, structural wavelength is significantly shorter and structural amplitude significantly higher than in the Midcontinent domain. The Bordering Basins domain outlines the southern and eastern edges of the Midcontinent domain. As emphasized by the basement DEM, several kilometers of structural relief occur across the boundary between these two domains, even though this boundary does not stand out on ground-surface topography. A plot of epicenters on the basement DEM supports models associating intraplate seismicity with the Midcontinent domain edge. Notably, certain changes in crustal thickness also coincide with distinct changes in basement depth.
DS201712-2679
2018
Yang, X.Chen, C., Hersh, G., Fischer, K.M., Andronicos, C.L., Pavlis, G.L., Hamburger, M.W., Marshak, S., Larson, T., Yang, X.Lithospheric discontinuities beneath the U.S. Midcontinent - signatures of Proterozoic terrane accretion and failed rifting.Earth and Planetary Science Letters, Vol. 481, pp. 223-235.United States, Illinois, Indiana, Kentuckygeophysics - seismics Reelfoot Rift

Abstract: Seismic discontinuities between the Moho and the inferred lithosphere-asthenosphere boundary (LAB) are known as mid-lithospheric discontinuities (MLDs) and have been ascribed to a variety of phenomena that are critical to understanding lithospheric growth and evolution. In this study, we used S-to-P converted waves recorded by the USArray Transportable Array and the OIINK (Ozarks-Illinois-Indiana-Kentucky) Flexible Array to investigate lithospheric structure beneath the central U.S. This region, a portion of North America's cratonic platform, provides an opportunity to explore how terrane accretion, cratonization, and subsequent rifting may have influenced lithospheric structure. The 3D common conversion point (CCP) volume produced by stacking back-projected Sp receiver functions reveals a general absence of negative converted phases at the depths of the LAB across much of the central U.S. This observation suggests a gradual velocity decrease between the lithosphere and asthenosphere. Within the lithosphere, the CCP stacks display negative arrivals at depths between 65 km and 125 km. We interpret these as MLDs resulting from the top of a layer of crystallized melts (sill-like igneous intrusions) or otherwise chemically modified lithosphere that is enriched in water and/or hydrous minerals. Chemical modification in this manner would cause a weak layer in the lithosphere that marks the MLDs. The depth and amplitude of negative MLD phases vary significantly both within and between the physiographic provinces of the midcontinent. Double, or overlapping, MLDs can be seen along Precambrian terrane boundaries and appear to result from stacked or imbricated lithospheric blocks. A prominent negative Sp phase can be clearly identified at 80 km depth within the Reelfoot Rift. This arrival aligns with the top of a zone of low shear-wave velocities, which suggests that it marks an unusually shallow seismic LAB for the midcontinent. This boundary would correspond to the top of a region of mechanically and chemically rejuvenated mantle that was likely emplaced during late Precambrian/early Cambrian rifting. These observations suggest that the lithospheric structure beneath the Reelfoot Rift may be an example of a global phenomenon in which MLDs act as weak zones that facilitate the removal of cratonic lithosphere that lies beneath.
DS202002-0200
2019
Yang, X.Lai, X., Yang, X.U-Pb ages and Hf isotope of zircons from a carbonatite dyke in the Bayan Obo Fe-REE deposit in Inner Mongolia: its geological significance.Acta Geologica Sinica, Vol. 93, 6, pp. 1783-1796.China, MongoliaREE

Abstract: Detailed studies on U?Pb ages and Hf isotope have been carried out in zircons from a carbonatite dyke associated with the Bayan Obo giant REE?Nb?Fe deposit, northern margin of the North China Craton (NCC), which provide insights into the plate tectonic in Paleoproterozoic. Analyses of small amounts of zircons extracted from a large sample of the Wu carbonatite dyke have yielded two ages of late Archaean and late Paleoproterozoic (with mean 207Pb/206Pb ages of 2521±25 Ma and 1921±14 Ma, respectively). Mineral inclusions in the zircon identified by Raman spectroscopy are all silicate minerals, and none of the zircon grains has the extremely high Th/U characteristic of carbonatite, which are consistent with crystallization of the zircon from silicate, and the zircon is suggested to be derived from trapped basement complex. Hf isotopes in the zircon from the studied carbonatite are different from grain to grain, suggesting the zircons were not all formed in one single process. Majority of ?Hf(t) values are compatible with ancient crustal sources with limited juvenile component. The Hf data and their TDM2 values also suggest a juvenile continental growth in Paleoproterozoic during the period of 1940-1957 Ma. Our data demonstrate the major crustal growth during the Paleoproterozoic in the northern margin of the NCC, coeval with the assembly of the supercontinent Columbia, and provide insights into the plate tectonic of the NCC in Paleoproterozoic.
DS2003-1522
2003
Yang, X.M.Yang, X.M., Yang, X.Y., Zheng, Y.F., Le Bas, M.J.A rare earth element rich carbonatite dyke at Bayan Obo, Inner Mongolia, NorthMineralogy and Petrology, Vol. 78, 1-2, pp. 93-110.ChinaREE, Deposit - Bayan Obo
DS200412-2173
2003
Yang, X.M.Yang, X.M., Yang, X.Y., Zheng, Y.F., Le Bas, M.J.A rare earth element rich carbonatite dyke at Bayan Obo, Inner Mongolia, North China.Mineralogy and Petrology, Vol. 78, 1-2, pp. 93-110.ChinaREE Deposit - Bayan Obo
DS2001-1279
2001
Yang, X.Y.Yang, X.Y., Zheng, Y.F., Liu, D., Dai, J.Chemical and carbon isotope compositions of fluid inclusions in peridotite xenoliths and eclogites...Physics and Chemistry of the Earth Pt. A. Solid Earth, Vol. 26, No. 9-10, pp. 705-18.ChinaGeodynamics
DS2001-1280
2001
Yang, X.Y.Yang, X.Y., Zheng, Y.F., Liu, D., Dai, J.Chemical and carbon isotope compositions of igneous rocks from Lower Yangtze region, constraints on sourcesPhysics and Chemistry of the Earth, Vol. 26, pt. A. No. 9-10, pp. 705-18.ChinaPeridotite - xenoliths
DS2003-1522
2003
Yang, X.Y.Yang, X.M., Yang, X.Y., Zheng, Y.F., Le Bas, M.J.A rare earth element rich carbonatite dyke at Bayan Obo, Inner Mongolia, NorthMineralogy and Petrology, Vol. 78, 1-2, pp. 93-110.ChinaREE, Deposit - Bayan Obo
DS200412-2173
2003
Yang, X.Y.Yang, X.M., Yang, X.Y., Zheng, Y.F., Le Bas, M.J.A rare earth element rich carbonatite dyke at Bayan Obo, Inner Mongolia, North China.Mineralogy and Petrology, Vol. 78, 1-2, pp. 93-110.ChinaREE Deposit - Bayan Obo
DS200512-1215
2005
Yang, X.Y.Yang, X.Y.Geochemistry of rare gases in eclogites from Dabie Shan orogenic belt, eastern China.Journal of the Geological Society of India, Vol. 65, 4, pp. 479-481.ChinaEclofites, UHP
DS202105-0765
2021
Yang, X.Y.Gonzalez-Alvarez, I., Stoppa, F., Yang, X.Y., Porwal, A.Introduction to the special issue, insights on carbonatites and their mineral exploration approach: a challenge towards resourcing critical metals.Ore Geology Reviews, Vol. 133, 104073, 7p. PdfGlobalcarbonatites

Abstract: Population growth and technological progress in the last 50 years have resulted in the global demand for mineral resources increasing by 400% since 1970, and it is further expected to almost double by 2050. This context forecasts a never-seen-before market for some specific mineral commodities, termed critical metals. The resource and supply flow of critical metals would be decisive for the economic well-being of economies in near future. Carbonatites are the most prospective host rocks for Rare Earth Elements (REEs), which constitute some of the most important critical elements. This special issue aims to contribute to the debate on understanding the genesis of carbonatites and their prospectivity for REEs (including exploration strategies), by presenting a wide variety of studies on carbonatites from around the globe.
DS2003-1523
2003
Yang, X-M.Yang, X-M., Yang, X-Y., Zheng, Y.F., Le Bas, M.J.A rare earth carbonatite dyke at Bayan Obo, Inner Mongolia, north ChinaMineralogy and Petrology, Vol. 78, 1-2, pp. 93-110.ChinaCarbonatite, Deposit - Bayan Obo
DS200712-1199
2007
Yang, X-M.Yang,X-M.Using the Rittmann serial index to define the alkalinity of igneous rocks.Neues Jahrbuch fur Geologie und Palaontologie , Vol. 184, 1, August pp. 95-103.TechnologyAlkalic
DS200712-1200
2007
Yang, X-M.Yang,X-M.Using the Rittmann serial index to define the alkalinity of igneous rocks.Neues Jahrbuch fur Geologie und Palaontologie , Vol. 184, 1, August pp. 95-103.TechnologyAlkalic
DS2003-1523
2003
Yang, X-Y.Yang, X-M., Yang, X-Y., Zheng, Y.F., Le Bas, M.J.A rare earth carbonatite dyke at Bayan Obo, Inner Mongolia, north ChinaMineralogy and Petrology, Vol. 78, 1-2, pp. 93-110.ChinaCarbonatite, Deposit - Bayan Obo
DS200912-0834
2009
Yang, X-Y.Yang, X-Y., Sun, W-D., Zhang, X., Zheng, Y-F.Geochemical constraints on the genesis of the Bayan Obo Fe Nb REE deposit in the Inner Mongolia, China.Geochimica et Cosmochimica Acta, Vol. 73, 5, March 1, pp. 1417-1436.China, MongoliaCarbonatite
DS201212-0393
2012
Yang, X-Y.Lai, X-D., Yang, X-Y.Geochemical characteristics of the Bayan Obo giant REE-Nb-Fe deposit: constraints on its genesis.Journal of South American Earth Sciences, in press available 58p.ChinaCarbonatite
DS201712-2701
2017
Yang, X-Y.Liu, Y-L., Ling, M-X., Williams, I.S., Yang, X-Y., Yan Wang, C., Sun, W.The formation of the giant Bayan Obo REE-Nb-Fe deposit, north China, Mesoproterozoic carbonatite and overprinted Palaeozoic dolomitization.Ore Geology Reviews, in press available, 47p.Chinadeposit - Bayan Obo

Abstract: The Bayan Obo ore deposit in Inner Mongolia, North China, the largest-known rare earth element (REE) deposit in the world, is closely associated with carbonatite dykes. Scarce zircon grains, with a wide range of ages and diverse origins, have been extracted from the Wu dyke, a REE-enriched calcitic carbonatite dyke 2?km from the East Ore Body of the Bayan Obo deposit. Three zircon populations were identified based on ages and trace element compositions: 1) Captured zircons with Paleoproterozoic and Archean ages. These zircons have REE patterns and moderate Th/U ratios similar to zircon with silicate inclusions from basement igneous rocks, which have been recognized as contaminants from wall rocks. 2) Carbonatite magmatic zircons with Mesoproterozoic ages. These zircons have high to extremely high Th/U ratios (13-1600), a characteristic signature of the Bayan Obo deposit. Two zircon grains yielded concordant 206Pb/238U ages (1.27?±?0.11?Ga???1.42?±?0.18?Ga) and 208Pb/232Th age (1.26?±?0.20?Ga) with calcite inclusions, indicating that the Wu dyke was emplaced at ca. 1.34?Ga, which coincides with a worldwide generation of Mesoproterozoic kimberlites, lamprophyres, carbonatites, and anorogenic magmatism. 3) Hydrothermal zircons with Caledonian and Triassic ages. The Caledonian zircon has 206Pb/238U age of 381?±?4?Ma and 208Pb/232Th age of 367?±?14?Ma with dolomite inclusion. These evidences are consistent with multiple stages of mineralization, Mesoproterozoic calcite carbonatite magmatism interacted by protracted fluxing of subduction-released Caledonian fluids during the closure of the Palaeo-Asian Ocean, coupled with interaction with the mantle wedge and metasomatism of overlying sedimentary carbonate.
DS201802-0250
2018
Yang, X-Y.Liu, Y-L., Ling, M-X., Williams, I.S., Yang, X-Y., Wang, C.Y.The formation of the giant Bayan Obo REE Nb Fe deposit, North China, Mesoproterozoic carbonatite and overprinted Paleozoic dolomitization.Ore Geology Reviews, Vol. 92, pp. 73-83.Chinadeposit - Bayan Obo

Abstract: The Bayan Obo ore deposit in Inner Mongolia, North China, the largest-known rare earth element (REE) deposit in the world, is closely associated with carbonatite dykes. Scarce zircon grains, with a wide range of ages and diverse origins, have been extracted from the Wu dyke, a REE-enriched calcitic carbonatite dyke 2?km from the East Ore Body of the Bayan Obo deposit. Three zircon populations were identified based on ages and trace element compositions: 1) Captured zircons with Paleoproterozoic and Archean ages. These zircons have REE patterns and moderate Th/U ratios similar to zircon with silicate inclusions from basement igneous rocks, which have been recognized as contaminants from wall rocks. 2) Carbonatite magmatic zircons with Mesoproterozoic ages. These zircons have high to extremely high Th/U ratios (13-1600), a characteristic signature of the Bayan Obo deposit. Two zircon grains yielded concordant 206Pb/238U ages (1.27?±?0.11?Ga???1.42?±?0.18?Ga) and 208Pb/232Th age (1.26?±?0.20?Ga) with calcite inclusions, indicating that the Wu dyke was emplaced at ca. 1.34?Ga, which coincides with a worldwide generation of Mesoproterozoic kimberlites, lamprophyres, carbonatites, and anorogenic magmatism. 3) Hydrothermal zircons with Caledonian and Triassic ages. The Caledonian zircon has 206Pb/238U age of 381?±?4?Ma and 208Pb/232Th age of 367?±?14?Ma with dolomite inclusion. These evidences are consistent with multiple stages of mineralization, Mesoproterozoic calcite carbonatite magmatism interacted by protracted fluxing of subduction-released Caledonian fluids during the closure of the Palaeo-Asian Ocean, coupled with interaction with the mantle wedge and metasomatism of overlying sedimentary carbonate.
DS200612-1552
2005
Yang, X-Z.Xia, Q-K., Sheng, Y-M., Yang, X-Z., Yu, H-M.Heterogeneity of water in garnets from UHP eclogites, eastern Dabie Shan, China.Chemical Geology, Vol. 224, 4, Dec. 20, pp. 237-246.ChinaUHP, Bixiling
DS2002-1760
2002
Yang, Y.Yang, Y., Liu, M.Deformation of convergent plates. Evidence from discrepancies between GPS velocities and rigid plate motions.Geophysical Research Letters, Vol. 29,10,May15,pp.110-MantleTectonics
DS200812-1294
2008
Yang, Y.Yang, Y., Forsyth, D.W.Attenuation in the upper mantle beneath southern California: physical state of the lithosphere and asenthosphere.Journal of Geophysical Research, Vol. 113, B03308.United States, CaliforniaTectonics
DS200812-1295
2008
Yang, Y.Yang, Y., Li, A., Ritzwoller, M.H.Crustal and uppermost mantle structure in southern Africa revealed from ambient noise and teleseismic tomography.Geophysical Journal International, In Press available.Africa, South AfricaGeophysics - seismics
DS200812-1296
2008
Yang, Y.Yang, Y., Li, A., Ritzwoller, M.H.Crustal and uppermost mantle structure in southern Africa revealed from ambient noise and teleseismic tomography.Geophysical Journal International, Vol. 174, 1, pp. 235-248.Africa, South AfricaGeophysics - seismics
DS200812-1297
2008
Yang, Y.Yang, Y., Li, A., Ritzwoller, M.H.Crustal and uppermost mantle structure in southern Africa revealed from ambient noise and teleseismic tomography.Geophysical Journal International, Vol. 174, pp. 235-248.Africa, South AfricaTomography
DS200912-0050
2009
Yang, Y.Bensen, G.D., Ritzwoller, M.H., Yang, Y.A 3 D shear velocity model of the crust and uppermost mantle beneath the United States from ambient seismic noise.Geophysical Journal International, Vol. 177, 3, pp. 1177-1196.United StatesGeophysics - seismics
DS200912-0835
2008
Yang, Y.Yang, Y., Ritzwoller, M.H., Lin, F.C., Moshetti, M.P., Shapiro, N.M.Structure of the upper crust and uppermost mantle beneath the western United States revealed by ambient noise and earthquake tomography.Journal of Geophysical Research, Vol. 113, B12, B12310.United StatesGeophysics - seismics
DS201012-0515
2010
Yang, Y.Moschetti, M.P., Rotzwoller, M.H., Lin, F-C., Yang, Y.Crustal shear wave velocity structure of the western United States inferred from ambient seismic noise and earthquake data.Journal of Geophysical Research, Vol. 115, B10 B10306.United StatesGeophysics - seismics
DS201112-0234
2011
Yang, Y.Dai, L-Q., Zhao, Z-F., Zheng, Y-F., Li, Q., Yang, Y., Dai, M.Zircon Hf-O isotope evidence for crust mantle interaction during continental deep subduction.Earth and Planetary Science Letters, Vol. 308, 1-2, pp. 229-244.MantleSubduction
DS201112-0603
2011
Yang, Y.Lin, F-C., Ritzwoller, M.H., Yang, Y., Moschetti, M.P., Fouch, M.J.Complex and variable crustal and uppermost mantle seismic anisotropy in the western United States.Nature Geoscience, Vol. 4, pp. 55-71.MantleTomography
DS201312-0009
2013
Yang, Y.Afonso, J.C., Fullea, J., Connolly, J., Rawlinson, N., Yang, Y., Jones, A.G.Multi observable thermochemical tomography: a new framework in integrated studies of the lithosphere.Goldschmidt 2013, AbstractMantleGeothermometry
DS201312-0347
2012
Yang, Y.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
DS201709-2077
2017
Yang, Y.Ying, Y., Chen, W., Lu, J., Jiang, S-Y., Yang, Y.In situ U-Th-Pb ages of the Miaoya carbonatite complex in the South Qinling orogenic belt, central China.Lithos, in press available, 57p.Chinacarbonatite - Miaoya

Abstract: The Miaoya carbonatite complex in the South Qinling orogenic belt hosts one of the largest rare earth element (REE)-Nb deposits in China that is composed of carbonatite and syenite. The emplacement age of the complex and the geochronological relationship between the carbonatite and syenite have long been debated. In this study, in situ U-Th-Pb ages have been obtained for the constituent minerals zircon, monazite and columbite from carbonatite and syenite of the Miaoya complex, together with their chemical and isotopic compositions. In situ trace element compositions for zircon from carbonatite and syenite are highly variable. The zircon displays slightly heavy REE (HREE)-enriched chondrite-normalized patterns with no Eu anomaly and various light REE (LREE) contents. In situ Th-Pb dating for zircon from the Miaoya complex by laser ablation ICP-MS yields ages of 442.6 ± 4.0 Ma (n = 53) for syenite and 426.5 ± 8.0 Ma (n = 23) for carbonatite. Monazite from carbonatite and syenite shows similar chondrite-normalized REE patterns and yields a consistent Th-Pb age of ~ 240 Ma. Based on petrographic and chemical composition, columbite from the carbonatite can be identified into two groups. The columbite dispersed within carbonatite is characterized by slightly LREE-enriched chondrite-normalized REE patterns, whereas columbite associated with apatite is characterized by LREE-depleted trends. Columbite has been further determined to have a weighted mean 206Pb/238U age of 232.8 ± 4.5 Ma (n = 9) using LA-ICP-MS. Detailed geochronological and chemical investigations suggest that there were two major episodes of magmatic/metasomatic activities in the formational history of the Miaoya carbonatite complex. The early alkaline magmatism emplaced in the Silurian was related to the opening of the Mianlue Ocean, whereas the late metasomatism or hydrothermal overprint occurred during the Triassic South Qinling orogeny. The latter serves as the major ore formation period for both REE (e.g., monazite) and Nb (e.g., columbite).
DS201805-0979
2018
Yang, Y.Song, W., Xi, C., Smith, M.P., Chakhmouradian, A.R., Brenna, M., Kynicky, J., Chen, W., Yang, Y., Tang, H.Genesis of the world's largest rare earth element deposit, Bayan Obo, China: protracted mineralization evolution over ~ 1.b.y.Geology, Vol. 48, 4, pp. 323-326.Chinadeposit - Bayan Obo

Abstract: The unique, giant, rare earth element (REE) deposit at Bayan Obo, northern China, is the world’s largest REE deposit. It is geologically complex, and its genesis is still debated. Here, we report in situ Th-Pb dating and Nd isotope ratios for monazite and Sr isotope ratios for dolomite and apatite from fresh drill cores. The measured monazite ages (361-913 Ma) and previously reported whole-rock Sm-Nd data show a linear relationship with the initial Nd isotope ratio, suggesting a single-stage evolution from a Sm-Nd source that was formed before 913 Ma. All monazites show consistent ?Nd(1.3Ga) values (0.3 ± 0.6) close to those of the adjacent 1.3 Ga carbonatite and mafic dikes. The primary dolomite and apatite show lower 87Sr/86Sr ratios (0.7024-0.7030) than the recrystallized dolomite (0.7038-0.7097). The REE ores at Bayan Obo are interpreted to have originally formed as products of ca. 1.3 Ga carbonatitic magmatism and to have undergone subsequent thermal perturbations induced by Sr-rich, but REE-poor, metamorphic fluids derived from nearby sedimentary rocks.
DS202009-1623
2019
Yang, Y.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.
DS202103-0426
2021
Yang, Y.Zhou, L., Chai, C., Zhang, W., Song, Y., Zhang, Z., Yang, Y.oI20-carbon: a new superhard carbon allotrope.Diamond & Related Materials, Vol. 113, 108284, 8p. PdfGlobalcarbon

Abstract: A new orthorhombic carbon crystal denoted oI20?carbon possessing the Immm space group was designed. Its structure is formed by stacking of a cage structure, which consists of 32 carbon atoms. Its stability and structural, mechanical and electronic properties were investigated by first-principles simulations. Density functional theory calculations show that this new carbon allotrope is thermodynamically stable (even more stable than synthesized T?carbon and supercubane). Ab initio molecular dynamics (AIMD) simulations show that it can maintain the structure above a temperature of 1000 K, indicating its excellent thermal stability. oI20?carbon can also maintain dynamic stability under a high pressure of 100 GPa. It is an anisotropic superhard material with a Vickers hardness of 46.62 GPa. Notably, the cage structure gives it a low density, which has a really small value among superhard carbon allotropes. In addition, it is worth noting that oI20?carbon has an indirect ultrawide band structure with a bandgap of 4.55 eV (HSE06), which is higher than that of most previously reported superhard carbon allotropes. All these outstanding properties show that it is a potential material for high-temperature, high-frequency electronic devices and the aerospace industry.
DS202108-1289
2021
Yang, Y.Hu, Z., Zeng, L., Foerster, M.W., Li, S., Zhao, L., Gao, L., Li, H., Yang, Y.Recycling of subducted continental crust: geochemical evidence from syn-exhumation Triassic alkaline mafic rocks of the southern Liaodong Peninsula, China.Lithos, 10.1016/j.lithos.2021.106353 13p. Chinaalkaline rocks

Abstract: Syn-exhumation mafic magmatism during continental collision provides insights into the crust-mantle reaction during deep subduction and the nature of orogenic lithospheric mantle in collisional orogens. In this study, we present a comprehensive data set of zircon U-Pb ages and whole-rock major-trace elements as well as Sr-Nd-Pb isotopes of alkaline mafic rocks from the southern Liaodong Peninsula, eastern China. Zircon U-Pb analyses yield Late Triassic age of 213 ± 3 to 217 ± 3 Ma, younger than the Middle Triassic ultrahigh-pressure metamorphic rocks of the Dabie-Sulu orogen. Thus, the alkaline mafic rocks are products of syn-exhumation magmatism during continental collision of the South and North China blocks. The rocks show shoshonitic affinities with high K2O (3.78-5.23 wt%) and K2O/Na2O (0.71-1.22). They are characterized by arc-like trace-element patterns with enriched LILE, Pb, and LREE, and depleted HFSE. They exhibit enriched Sr-Nd isotopic compositions with high initial 87Sr/86Sr isotopic ratios of 0.7058-0.7061 and negative ?Nd(t) values of ?13.0 to ?15.1. These results suggest involvement of recycled continental crust in their mantle source. The mantle source likely formed by the metasomatic reaction of subducted continental crust-derived melts with the overlying subcontinental lithospheric mantle during the Triassic continental collision. Decompressional melting of this metasomatized mantle formed syn-exhumation mafic magmas during the transition from convergent to extensional tectonics in the Late Triassic. Accordingly, mafic rocks from the southern Liaodong Peninsula provide a geochemical record of the subduction and recycling of continental crust into the mantle and melt-mantle reaction induced metasomatism within the orogen.
DS202205-0672
2022
Yang, Y.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.
DS200712-1230
2007
Yang, Y.H.Zhang, R.Y., Liou, J.G., Zheng, J.P., Yang, Y.H.Mineral REE ad Lu Hf isotope geochemistry of zircon in the mantle - derived eclogite from Donghai the Sulu UHP terrane: new constraints for the origin of eclogite.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 250.ChinaGeochronology
DS200712-1231
2007
Yang, Y.H.Zhang, R.Y., Liou, J.G., Zheng, J.P., Yang, Y.H.Mineral REE ad Lu Hf isotope geochemistry of zircon in the mantle - derived eclogite from Donghai the Sulu UHP terrane: new constraints for the origin of eclogite.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 250.ChinaGeochronology
DS200812-1312
2008
Yang, Y.H.Zhang, R.Y., Pan, Y.M., Yang, Y.H., Li, T.F., Liou, J.G., Yang, J.S.Chemical composition and ultrahigh P metamorphism of garnet peridotites from the Sulu UHP terrane, China: investigation of major, trace elements and Hf isotopesChemical Geology, in press available,ChinaUHP
DS200812-1313
2008
Yang, Y.H.Zhang, R.Y., Pan, Y.M., Yang, Y.H., Li, T.F., Liou, J.G., Yang, J.S.Chemical composition and ultrahigh P metamorphism of garnet peridotites from the Sulu UHP terrane, China: investigation of major trace elements and Hf isotopes.Chemical Geology, Vol. 255, 1-2, Sept. 30, pp. 250-264.ChinaUHP
DS2003-1524
2003
Yang, Y.S.Yang, Y.S., Wooden, J.L., Wu. C.L., Liu, F.L., Xu. ZQ, Shi, R.D., Katayama, I.SHRIMP U Pb dating of coesite bearing zircon from the ultrahigh pressureJournal of Metamorphic Geology, Vol. 21, 6, pp. 551-60.ChinaUHP
DS200412-2174
2003
Yang, Y.S.Yang, Y.S., Wooden, J.L., Wu,C.L., Liu, F.L., Xu,ZQ, Shi, R.D., Katayama, I., Liou, J.G., Maruyama, S.SHRIMP U Pb dating of coesite bearing zircon from the ultrahigh pressure metamorphic rocks, Sulu terrane, east China.Journal of Metamorphic Geology, Vol. 21, 6, pp. 551-60.ChinaUHP
DS200612-1547
2006
Yang, Y-H.Wu, F-Y., Walker, R.J., Yang, Y-H., Yuan, H-L., Yang, J-H.The chemical temporal evolution of lithospheric mantle underlying the North Chin a Craton.Geochimica et Cosmochimica Acta, Vol. 70, 19, pp. 5013-5034.ChinaDeposit - Tieling, Fuxian, Mengyin - geochemistry -SCLM
DS200612-1548
2006
Yang, Y-H.Wu, F-Y., Yang, Y-H., Xie, L-W., Yang, J-H., Xu, P.Hf isotopic compositions of the standard zircons and baddeleyites used in U Pb geochronology.Chemical Geology, Vol. 234, 1-2, Oct 30, pp. 105-126.ChinaUHP, geochronology
DS200912-0114
2009
Yang, Y-H.Chu, Z-Y., Wu, F-Y., Walker, R.J., Rudnick, R.L., Pitcher, L., Puchtel, I.S., Yang, Y-H., Wilde, S.A.Temporal evolution of the lithospheric mantle beneath the North Chin a Craton.Journal of Petrology, Vol. 50, 10, pp. 1857-1898.ChinaGeodynamics
DS200912-0836
2009
Yang, Y-H.Yang, Y-H., Wu, F-Y., Wilde, S.A., Liu, X-M., Zhang, Y-B., Xie, L-W., Yang, J-H.In in situ perovskite Sr Nd isotopic constraints on the petrogenesis of the Ordovician Mengyin kimberlites in North Chin a craton.Chemical Geology, Vol. 264, 1-4, pp. 24-42.ChinaDeposit - Mengyin
DS200912-0866
2009
Yang, Y-H.Zhu-Yin Chu, Wu, F-Y., Walker, R.J., Rudnick, R.L., Pitcher, L., Puchtel, I.S., Yang, Y-H., Wilde, S.A.Temporal evolution of the lithospheric mantle beneath the eastern north Chin a craton.Journal of Petrology, Vol. 50, 10, October, pp. 1857-1898.ChinaTectonics
DS201012-0765
2010
Yang, Y-H.Su, B-X., Zhang, H-F., Sakyi, P.A., Yang, Y-H., Ying, J-F., Tang, Y-J., Qin, K-Z., Xiao, Y., Zhao, Mao, MaThe origin of spongy texture in minerals of mantle xenoliths from the western Qinling, central China.Contributions to Mineralogy and Petrology, in press available, 18p.ChinaXenoliths
DS201012-0766
2010
Yang, Y-H.Su, B-X., Zhang, H-F., Sakyi, P.A., Ying, J-F., Tang, Y-J., Yang, Y-H., Qin, K-Z., Xiao, Y., Zhao, X-M.Compositionally stratified lithosphere and carbonatite metasomatism recorded in mantle xenoliths from the Western Qinling (Central China).Lithos, Vol. 116, pp. 111-128.ChinaCarbonatite
DS201012-0861
2010
Yang, Y-H.Wu, F.Y., Yang, Y-H., Mitchell, R.H., Li, J-H., Yang, J-H., Zhang, Y-B.In situ U Pb age determination and Nd isotopic analysis of perovskites from kimberlites in southern Africa and Somerset Island, Canada.Lithos, Vol. 115, pp. 205-222.Canada, Nunavut, Africa, South AfricaGeochronology
DS201112-0594
2011
Yang, Y-H.Li, Q., Wu, F-Y., Li, X-H., Qiu, Z-L., Yang, Y-H., Tang, G-Q.Precisely dating Paleozoic kimberlites in the North Chin a craton and Hf isotopic constraints on the evolution of the subcontinental lithospheric mantle.Lithos, Vol. 126, pp. 127-134.ChinaMengyin, Fuxian
DS201112-0595
2011
Yang, Y-H.Li, Q-L., Wu, F-Y., Li, X-H., Qiu, Z-L., Liu, Y., Yang, Y-H., Tang, G-Q.Precise age determin ation of the Paleozoic kimberlites in North Chin a craton and Hf isotopic constraint on the evolution of its subcontinental lithospheric mantle.Goldschmidt Conference 2011, abstract p.1316.ChinaMengyin, Fuxian
DS201112-1122
2011
Yang, Y-H.Wu, F-Y., Yang, Y-H.,Li, Q-L., Mitchell, R.H., Dawson, J.B., Brandl, G., Yuhara, M.In situ determination of U-Pb ages and Sr-Nd-Hf isotopic constraints on the petrogenesis of the Phalaborwa carbonatites complex, South Africa.Lithos, Vol. 127, 1-2, pp. 309-322.Africa, South AfricaCarbonatite, geochronology, Palaborwa
DS201212-0797
2013
Yang, Y-H.Xu, W-L., Zhou, Q-J., Pei, F-P., Gao, S., Li, Q-L., Yang, Y-H.Destructive of the North Chin a craton: delamin ation or thermal/chemical erosion? Mineral chemistry and oxygen isotope insights from websterite xenoliths.Gondwana Research, Vol. 23, 1, pp. 119-129.ChinaCraton, destruction
DS201212-0812
2012
Yang, Y-H.Zhang, H-F., Yang,Y-H., Santosh, M., Zhao, X-M., Ying, J-F., Xiao, Y.Evolution of the Archean and Paleoproterozoic lower crust beneath the Trans-North Chin a Orogen and the western block of the north Chin a craton.Gondwana Research, Vol. 22, 1, pp. 73-85.ChinaGeochronology, tectonics, cratons
DS201312-0984
2013
Yang, Y-H.Wu, F-Y., Mitchell, R.H., Li, Q-L., Liu, C-Z., Yang, Y-H.In situ U-Pb age determination and Sr-Nd isotopic analysis of perovskite from the Premier ( Cullinan) kimberlite, South Africa. ~1150Chemical Geology, Vol. 353, pp. 83-95.Africa, South AfricaGeochronology
DS201312-0986
2013
Yang, Y-H.Wu,F-Y., Arzamastsev, A.A., Mitchell, R.H., Li, Q-L., Sun, J., Yang, Y-H., Wang, R-C.Emplacement age and Sr-Nd isotopic compositions of the AfrikAnd a alkaline ultramafic complex, Kola Peninsula, Russia.Chemical Geology, Vol. 353, pp. 210-229.Russia, Kola PeninsulaAfrikanda Complex
DS201412-0897
2014
Yang, Y-H.Sun, J., Liu, C-Z., Tappe, S., Kostrovitsky, S.I., Wu, F-Y., Yakovlev, D., Yang, Y-H., Yang, J-H.Repeated kimberlite magmatism beneath Yakutia and its relationship to Siberian flood volcanism: insights from in situ U-Pb and Sr-Nd perovskite isotope analysis.Earth and Planetary Science Letters, Vol. 404, Oct. pp. 283-295.Russia, YakutiaKimberlite magmatism
DS201703-0440
2017
Yang, Y-H.Wu, F-Y.,Mitchell, R.H., Li, Q-L., Zhang, C., Yang, Y-H.Emplacement age and isotopic composition of the Prairie Lake carbonatite complex, northwestern Ontario, Canada.Geological Magazine, Vol. 154, 2, pp. 217-236.Canada, OntarioCarbonatite

Abstract: Alkaline rock and carbonatite complexes, including the Prairie Lake complex (NW Ontario), are widely distributed in the Canadian region of the Midcontinent Rift in North America. It has been suggested that these complexes were emplaced during the main stage of rifting magmatism and are related to a mantle plume. The Prairie Lake complex is composed of carbonatite, ijolite and potassic nepheline syenite. Two samples of baddeleyite from the carbonatite yield U-Pb ages of 1157.2±2.3 and 1158.2±3.8 Ma, identical to the age of 1163.6±3.6 Ma obtained for baddeleyite from the ijolite. Apatite from the carbonatite yields the same U-Pb age of ~1160 Ma using TIMS, SIMS and laser ablation techniques. These ages indicate that the various rocks within the complex were synchronously emplaced at about 1160 Ma. The carbonatite, ijolite and syenite have identical Sr, Nd and Hf isotopic compositions with a 87Sr/86Sr ratio of ~0.70254, and positive ?Nd(t)1160 and ?Hf(t)1160 values of ~+3.5 and ~+4.6, respectively, indicating that the silicate and carbonatitic rocks are co-genetic and related by simple fractional crystallization from a magma derived from a weakly depleted mantle. These age determinations extend the period of magmatism in the Midcontinent Rift in the Lake Superior area to 1160 Ma, but do not indicate whether the magmatism is associated with passive continental rifting or the initial stages of plume-induced rifting.
DS201709-2061
2017
Yang, Y-H.Sun, J., Liu, C-Z., Kostrovisky, S.I., Wu, F-Y., Yang, J-H., Chu, Z., Yang, Y-H.Constraints from peridotites in the Obnazhennaya kimberlite.Goldschmidt Conference, abstract 1p.Russiadeposit - Obnazhennaya

Abstract: The characteristics of the sub-continental lithospheric mantle (SCLM) post-date the Siberian plume event (250 Ma) is still unclear; nearly all published data for mantle xenoliths are from a single kimberlite erupt before he Siberian plume (Udachnaya). We report major elements of the whole rock, trace elements data of clinopyroxene and Re-Os isotope and PGE concentration of mantle xenoliths from the Obnazhennaya kimberlite pipe (160 Ma). The Obnazhennaya mantle xenoliths, including spinel harzburgites, spinel dunites, spinel lherzolites, spinel-garnet lherzolite. The spinel harzburgites and dunites have refractory compositions, with 0.23-1.35 wt.% Al2O3, 0.41-3.11 wt.% CaO and 0.00-0.09 wt.% TiO2. Clinopyroxenes in harzburgites and dunites have lower Na2O but higher Cr2O3 contents. Modeling of the Y and Yb contents in clinopyroxenes indicates that the spinel harzburgites and dunites have been subjected to ca. 12-17% degrees of partial melting. The spinel harzburgites and dunites have 187Os/188Os of 0.11227-0.11637, giving a TRD age of 1.6-2.2 Ga. This suggests that old cratonic mantle still existed beneath the Obnazhennaya. In contrast, the lherzolites (both spinel- and spinel-garnet-) have more fertile compositions, containing 2.16-6.55 wt.% Al2O3, 2.91-7.55 wt.% CaO and 0.04-0.15 wt.% TiO2. Both spinel and spinelgarnet lherzolites have more radiogenic 187Os/188Os ratios (0.11931-0.17627), enriched P-PGEs. The higher Al2O3 and Os content and depleted IPGE character of these lherzolites suggest that they were not juvenile mantle accreted by Siberian mantle plume but the refertilized ancient mantle. Therefore, our result suggest that the cratonic mantle beneath the Obnazhennaya has not been replaced by juvenile mantle during the Siberian mantle plume.
DS201709-2062
2017
Yang, Y-H.Sun, J., Liu, C-Z., Kostrovisky, S.I., Wu, F-Y., Yang, J-H., Chu, Z., Yang, Y-H.Composition of the lithospheric mantle in the northern Siberian craton: constraints from the peridotites in the Obnazhennaya kimberlite.Goldschmidt Conference, abstract 1p.Russia, Siberiadeposit - Obnazhennaya

Abstract: The characteristics of the sub-continental lithospheric mantle (SCLM) post-date the Siberian plume event (250 Ma) is still unclear; nearly all published data for mantle xenoliths are from a single kimberlite erupt before he Siberian plume (Udachnaya). We report major elements of the whole rock, trace elements data of clinopyroxene and Re-Os isotope and PGE concentration of mantle xenoliths from the Obnazhennaya kimberlite pipe (160 Ma). The Obnazhennaya mantle xenoliths, including spinel harzburgites, spinel dunites, spinel lherzolites, spinel-garnet lherzolite. The spinel harzburgites and dunites have refractory compositions, with 0.23-1.35 wt.% Al2O3, 0.41-3.11 wt.% CaO and 0.00-0.09 wt.% TiO2. Clinopyroxenes in harzburgites and dunites have lower Na2O but higher Cr2O3 contents. Modeling of the Y and Yb contents in clinopyroxenes indicates that the spinel harzburgites and dunites have been subjected to ca. 12-17% degrees of partial melting. The spinel harzburgites and dunites have 187Os/188Os of 0.11227-0.11637, giving a TRD age of 1.6-2.2 Ga. This suggests that old cratonic mantle still existed beneath the Obnazhennaya. In contrast, the lherzolites (both spinel- and spinel-garnet-) have more fertile compositions, containing 2.16-6.55 wt.% Al2O3, 2.91-7.55 wt.% CaO and 0.04-0.15 wt.% TiO2. Both spinel and spinelgarnet lherzolites have more radiogenic 187Os/188Os ratios (0.11931-0.17627), enriched P-PGEs. The higher Al2O3 and Os content and depleted IPGE character of these lherzolites suggest that they were not juvenile mantle accreted by Siberian mantle plume but the refertilized ancient mantle. Therefore, our result suggest that the cratonic mantle beneath the Obnazhennaya has not been replaced by juvenile mantle during the Siberian mantle plume.
DS201803-0488
2018
Yang, Y-H.Yang, Y-H., Wu, F-Y., Yang, J-H., Mitchell, R.H., Zhao, Z-F., Xie, L-W., Huang, C., Ma, Q., Yang, M., Zhao, H.U-Pb age determination of schorlomite garnet by laser ablation inductively coupled plasma mass spectrometry. Magnet Cove, Fanshan, Ozernaya, Alno, Prairie LakeJournal of Analytical At. Spectrometry, Vol. 33, pp. 231-239.United States, Arkansas, China, Hebei, Russia, Kola Peninsula, Europe, Sweden, Canada, Ontariogeochronology

Abstract: We report the first U-Pb geochronological investigation of schorlomite garnet from carbonatite and alkaline complexes and demonstrate its applicability for U-Pb age determination using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) due to its relatively high U and Th abundances and negligible common Pb content. The comparative matrix effects of laser ablation of zircon and schorlomite are investigated and demonstrate the necessity of a suitable matrix-matched reference material for schorlomite geochronology. Laser-induced elemental fractional and instrumental mass discrimination were externally-corrected using an in house schorlomite reference material (WS20) for U-Pb geochronology. In order to validate the effectiveness and robustness of our analytical protocol, we demonstrate the veracity of U-Pb age determination for five schorlomite samples from: the Magnet Cove complex, Arkansas (USA); the Fanshan ultrapotassic complex, Hebei (China); the Ozernaya alkaline ultramafic complex, Kola Peninsula (Russia); the Alnö alkaline-rock carbonatite complex (Sweden); and the Prairie Lake carbonatite complex, Ontario (Canada). The schorlomite U-Pb ages range from 96 Ma to 1160 Ma, and are almost identical to ages determined from other accessory minerals in these complexes and support the reliability of our analytical protocol. Schorlomite garnet U-Pb geochronology is considered to be a promising new technique for understanding the genesis of carbonatites, alkaline rocks, and related rare-metal deposits.
DS201810-2360
2018
Yang, Y-H.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.
DS201912-2835
2019
Yang, Y-H.Yang, Y-H., Wu, F-Y., Qiu-Li, L., Rojas-Agramonte, Y., Yang, J-H., Yang, L., Ma, Q., Xie, L-W., Huang, C., Fan, H-R., Zhao, Z-F., Xu, C.In situ U-Th-Pb dating and Sr-Nd isotope analysis of bastnasite by LA-(MC)-ICP-MS.Geostandards and Geoanalltical Research, Vol. 43, 3, pp. 543-565.China, Europe, Sweden, Asia, Mongolia, United States, Africa, Malawi, MadagascarREE

Abstract: Bastnäsite is the end member of a large group of carbonate-fluoride minerals with the common formula (REE) CO3F•CaCO3. This group is generally widespread and, despite never occurring in large quantities, represents the major economic light rare earth element (LREE) mineral in deposits related to carbonatite and alkaline intrusions. Since bastnäsite is easily altered and commonly contains inclusions of earlier?crystallised minerals, in situ analysis is considered the most suitable method to measure its U?Th?Pb and Sr?Nd isotopic compositions. Electron probe microanalysis and laser ablation (multi?collector) inductively coupled plasma?mass spectrometry of forty?six bastnäsite samples from LREE deposits in China, Pakistan, Sweden, Mongolia, USA, Malawi and Madagascar indicate that this mineral typically has high Th and LREE and moderate U and Sr contents. Analysis of an in?house bastnäsite reference material (K?9) demonstrated that precise and accurate U?Th?Pb ages could be obtained after common Pb correction. Moreover, the Th?Pb age with its high precision is preferable to the U?Pb age because most bastnäsites have relatively high Th rather than U contents. These results will have significant implications for understanding the genesis of endogenous ore deposits and formation processes related to metallogenic geochronology research.
DS202112-1954
2021
Yang, Y-H.Wang, J., Su, B-X., Ferrero, S., Malaviarachchi, S.P.K., Sakyi, P.A., Yang, Y-H., Dharmapriya, P.L.Crustal derivation of the ca 475 Ma Eppawala carbonatites in Sri Lanka.Journal of Petrology, Vol. 62, 11, pp.1-18. pdfAsia, Sri Lankacarbonatite

Abstract: Although a mantle origin of carbonatites has long been advocated, a few carbonatite bodies with crustal fingerprints have been identified. The Eppawala carbonatites in Sri Lanka are more similar to orogenic carbonatites than those formed in stable cratons and within plate rifts. They occur within the Pan-African orogenic belt and have a formation age of ca. 475 Ma newly obtained in this study with no contemporary mantle-related magmatism. These carbonatites have higher (87Sr/86Sr)i ratios (0•70479-0•70524) and more enriched Nd and Hf isotopic compositions than carbonatites reported in other parts of the world. Model ages (1•3-2•0 Ga) of both Nd and Hf isotopes [apatite ?Nd(t)?=??9•2 to ?4•7; rutile ?Hf(t)?=??22•0 to ?8•02] are in the age range of metamorphic basement in Sri Lanka, and the carbon and oxygen isotopic compositions (?13CPDB?=??2•36 to ?1•71; ?18OSMOW?=?13•91-15•13) lie between those of mantle-derived carbonatites and marble. These crustal signatures are compatible with the chemistry of accessory minerals in the carbonatites, such as Ni-free olivine and Al- and Cr-poor rutile. Modeling results demonstrate that the Eppawala carbonatite magmas originated from a mixture of basement gneisses and marbles, probably during regional metamorphism. This interpretation is supported by the occurrence of the carbonatites along, or near, the axes of synforms and antiforms where granitic gneiss and marble are exposed. Therefore, we propose that the Eppawala carbonatites constitute another rare example of a carbonatitic magma that was derived from melting of a sedimentary carbonate protolith. Our findings suggest that other orogenic carbonatites with similar features should be re-examined to re-evaluate their origin.
DS1993-1789
1993
Yang, Z.Yan Chen, Courtillot, V., Cogne, J-P., Besse, J., Yang, Z., Enkin, R.The configuration of Asia prior to the collision of India: Cretaceous paleomagnetic constraints.Journal of Geophysical Research, Vol. 98, No. B 12, December 10, pp. 21, 927-21, 941.GlobalPaleomagnetics
DS200612-0603
2006
Yang, Z.Hou, Z., Tian, S., Yuan, Z., Xie, Y., Yin, S., Yi, L., Fei, H., Yang, Z.The Himalayan collision zone carbonatites in western Sichuan, SW China: petrogenesis, mantle source and tectonic implication.Earth and Planetary Science Letters, in pressAsia, ChinaCarbonatite
DS200612-1565
2006
Yang, Z.Yang, Z., Woolley, A.Carbonatites in China: a review.Journal of Asian Earth Sciences, Vol. 27, 5, Sept. 15, pp. 559-750.ChinaCarbonatite
DS200712-0133
2007
Yang, Z.Campbell, L.S., Wall, F., Henderson, P., Zhang, P., Tao, K., Yang, Z.The character and context of zircons from the Bayan Obo Fe Nb REE deposit, Inner Mongolia.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 97-98.Asia, MongoliaCarbonatite
DS200712-0134
2007
Yang, Z.Campbell, L.S., Wall, F., Henderson, P., Zhang, P., Tao, K., Yang, Z.The character and context of zircons from the Bayan Obo Fe Nb REE deposit, Inner Mongolia.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 97-98.Asia, MongoliaCarbonatite
DS200912-0313
2009
Yang, Z.Hou, Z., Tian, S., Xie, Y., Yang, Z., Yuan, Z., Yin, S., Yi, L., Fei, H., Zou, T., Bai, G., Li, X.The Himalayan Mianning Dechang REE belt associated with carbonatite alkaline complexes eastern Indo Asian collision zone, SW China.Ore Geology Reviews, Vol. 36, 1-3, pp. 65-89.ChinaCarbonatite
DS201201-0836
2012
Yang, Z.Chen, W-P., Hung, S-H., Tseng, T-L., Brudzinski, M., Yang, Z., Nowack, R.L.Rheology of the continental lithosphere: progress and new perspectives.Gondwana Research, Vol. 21, 1, pp. 4-18.MantleGeodynamics
DS201312-0047
2013
Yang, Z.Bader, T., Ratschbacher, L., Franz, L., Yang, Z., Hofmann, M., Linneman, U., Yuan, H.The heart of Chin a revisited. 1. Proterozoic tectonics of the Qin Mountains in the core of supercontinent Rodinia.Tectonics, Vol. 32, 3, pp. 661-687.ChinaMagmatism - Dabie orogen
DS201508-0366
2015
Yang, Z.Liu, Y., Chen, Z., Yang, Z., Sun, X., Zhu, Z., Zhang, Q.Mineralogical and geochemical studies of brecciated ores in the Dalucao REE deposit, Sichuan Province, southwestern China.Ore Geology Reviews, Vol. 70, pp. 613-636.ChinaCarbonatite
DS201809-2054
2018
Yang, Z.Lawley, C.J.M., Kjarsgaard, B.A., Jackson, S.E., Yang, Z., Petts, D.C.Olivine and clinopyroxene mantle xenocryst geochemistry from the Kirkland Lake kimberlite field, Ontario.Geological Survey of Canada, Open File 8376, 9p.Canada, Ontariogeochemistry
DS201810-2342
2018
Yang, Z.Lawley, C., Kjarsgaard, B., Jackson, S., Yang, Z., Petts, D., Roots, E.Trace metal and isotopic depth profiles through the Abitibi. Kirkland Lake kimberlite field.Lithos, Vol. 314-315, pp. 520-533.Canada, Ontariodeposit - Kirkland Lake

Abstract: Geophysical imaging of trans-lithospheric structures provide a spatial link between ore deposits in the crust and the underlying cratonic mantle. However, the deep lithosphere's role in ore deposit genesis remains poorly understood because remotely acquired datasets do not provide any direct constraints on the behaviour of ore elements within these mantle-roots. The abundance and behaviour of ore elements governs the metallic endowment of the cratonic mantle and the economic potential of mantle-derived magmas. Herein we present in situ electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) geochemical datasets for clinopyroxene and olivine mantle xenocrysts from the Jurassic Kirkland Lake kimberlite field, Abitibi greenstone belt, Canada. We specifically focus on unconventional trace elements, including ore elements with chalcophile and/or siderophile affinities (Ag-As-Au-Bi-Cu-Mo-Pb-Pt-Pd-Sb-Se-Sn-Te-W-Zn). Robust principal component analysis suggests that low-T, large-ion lithophile element alteration (Ba-Sr), which likely occurred during kimberlite emplacement, represents the largest source of variance for the xenocryst dataset. PT-dependent element partitioning during sub-solidus equilibration represents the second most important control on olivine and clinopyroxene chemistry. We demonstrate that least-altered, high-PT mantle silicates are, in fact, a significant mineral host for a range of ore elements (Cu-Zn ± Ag ± As ± Se ± Sn ± Mo) within equilibrated, garnet peridotite at depth (70-190 km). Statistical analysis of the raw, individual mass sweeps for each LA-ICP-MS signal suggest that the most abundant ore elements (Cu-Zn) occur predominantly as PT-dependent substitution reactions with the dominant mineral-forming elements, rather than as inclusions. A subset of high-PT olivine (160-180 km) yields Fe-Ni-S-poor and Na (Au ± Pt ± Pd)-rich compositions, which may reflect metasomatism, sulphide segregation and trapping of precious metal-bearing fluids at the base of the lithosphere. These anomalous mantle fragments possibly represent the first, direct sampling of precious metal-modified mantle peridotite beneath the Abitibi. Mid-PT olivine xenocrysts (70-120 km), which yield Mg-rich and high field-strength element-poor compositions, document a highly melt-depleted segment of mantle peridotite coincident with and below a shallow-dipping, low-seismic-velocity anomaly and conductive feature of the Kirkland Lake mid-lithosphere at 70-100 km. We speculate that the trace element signature of mid-PT xenocrysts documents the re-distribution of high-charge and incompatible elements from refractory garnet peridotite to phlogopite- and/or amphibole-bearing peridotite with conductive metasomatic up-flow zones. The rapid, sub-solidus diffusion of elements at high-T suggest that these processes likely occurred during, and/or immediately preceding, kimberlite volcanism. New in situ Pb isotope analyses of clinopyroxene xenocrysts sampled from metasomatized, low-Al garnet peridotite, however, also document ancient metasomatic events that likely pre-date Jurassic kimberlitic volcanism by at least one billion years.
DS202007-1159
2020
Yang, Z.Li, W, Yang, Z., Chiaradia, M., Yong, L., Caho, Yu., Zhang, J.Redox state of southern Tibetan mantle and ultrapotassic magmas. Lhasa TerraneGeology, Vol. 48, 7, pp. 733-736. pdfAsia, Tibetalkaline rocks

Abstract: The redox state of Earth’s upper mantle in several tectonic settings, such as cratonic mantle, oceanic mantle, and mantle wedges beneath magmatic arcs, has been well documented. In contrast, oxygen fugacity (graphic) data of upper mantle under orogens worldwide are rare, and the mechanism responsible for the mantle graphic condition under orogens is not well constrained. In this study, we investigated the graphic of mantle xenoliths derived from the southern Tibetan lithospheric mantle beneath the Himalayan orogen, and that of postcollisional ultrapotassic volcanic rocks hosting the xenoliths. The graphic of mantle xenoliths ranges from ?FMQ = +0.5 to +1.2 (where ?FMQ is the deviation of log graphic from the fayalite-magnetite-quartz buffer), indicating that the southern Tibetan lithospheric mantle is more oxidized than cratonic and oceanic mantle, and it falls within the typical range of mantle wedge graphic values. Mineralogical evidence suggests that water-rich fluids and sediment melts liberated from both the subducting Neo-Tethyan oceanic slab and perhaps the Indian continental plate could have oxidized the southern Tibetan lithospheric mantle. The graphic conditions of ultrapotassic magmas show a shift toward more oxidized conditions during ascent (from ?FMQ = +0.8 to +3.0). Crustal evolution processes (e.g., fractionation) could influence magmatic graphic, and thus the redox state of mantle-derived magma may not simply represent its mantle source.
DS202002-0203
2020
Yang, Z-F.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.
DS202011-2044
2020
Yang, Z-F.Hou, X-Z., Yang, Z-F., Wang, Z-J.The occurrence characteristics and recovery potential of middle-heavy rare earth elements in the Bayan Obo deposit, northern China.Ore Geology Reviews, Vol. 126, 103737, 13p. PdfChinaREE

Abstract: The Bayan Obo deposit is a world-class Fe-REE-Nb deposit, and its reserves of rare earth element (REE) resources rank the first over the world. In the face of the current situation of insufficient utilization rate of rare earth resources and scarcity of middle-heavy rare earth elements (M?HREE) resources, the Bayan Obo deposit with such a huge amount of M?HREE cannot be underestimated. In this paper, the occurrence characteristics of M?HREE in different types of iron ore in the Bayan Obo main ore body are studied by using field emission scanning electron microscope (FESEM), energy dispersive spectrometer (EDS) and advanced mineral identification and characterisation system (AMICS), and the enrichment mechanism is also discussed. The results show that both Sm and Y are the most abundant M?HREE in each type of iron ore in the main ore body, and the content of M?HREE accounts for 1.41%-5.57% of total REE, among which the content of M?HREE in aegirine type Nb-REE-Fe ore (824.47 ppm) and fluorite type Nb-REE-Fe ore (794.82 ppm) are higher, and the content of M?HREE in massive type Nb-REE-Fe ore is lower (318.49 ppm). The main minerals containing M?HREE are bastnasite, parisite, Huanghoite, monazite, aeschynite and fergusonite, among which the content of M?HREE in fergusonite and aeschynite are the highest. According to the characteristics of mineral paragenetic association of REE in this ore district, it is believed that the REE migrates mainly in many different forms of complexes. Heavy rare earth elements (HREE) mainly experienced carbonatite magmatism stage, sodium-fluorine metasomatism stage and late vein mineralization stage, and finally got enrichment.
DS201312-0992
2013
Yang, Z-j.Yang, Z-j., Liang, R., Zeng, X-q., Ge, T-y., Al Qun, Zhenh, Y-l., Peng, M-s.Study on the micro-infrared spectra and origin of polycrystalline diamonds from Mengyin kimberlite pipes.Spectroscopy and Spectral Analysis, Vol. 32, 8, pp. 1512-1518.ChinaDeposit - Mengyin
DS201312-1008
2013
Yang, Z-J.Zeng, X-Q., Zheng, Y-L., Yang, Z-J., Ai, Hu, Q.Study on the micro-FTIR and raman spectra of the alluvial diamonds from Yangtze craton and their geological significance.Spectroscopy and Spectral Analysis, Vol. 33, no. 10.pp. 2694-2699.ChinaAlluvials
DS201702-0254
2017
Yang, Z-M.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.
DS1983-0573
1983
YANG DAYUShen zhutong, YANG DAYU, Sun guoxian, CHEN XICHENG.The Microstructure of Synthetic DiamondsKexue Tongbao, Vol. 28, No. 1, PP. 24-29.ChinaMineralogy
DS1985-0749
1985
Yang fengying, FANG QINGSONG.Yan binggang, LIANG RIXUAN, Yang fengying, FANG QINGSONG.Some characters of diamond and diamond bearing ultramafic rocks in Xizang(Tibet).*CHI27th. International Geological Congress Held China**chi, pp. 341-350ChinaUltramafics, Diamond Genesis
DS1989-0907
1989
Yang GuangshuLuo Huiwen, Yang GuangshuThe characteristics of lamproite in Zhenyuan area Guizhou.*CHIYanshi Kuangwuxue Zazhi, (Acta Petrologica et Mineralogica) *CHI, Vol. 8, No. 2, pp. 97-109ChinaLamproite, Geochronology
DS1990-1607
1990
Yang JianjunYang 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
DS1992-1715
1992
Yang JianjunYang JianjunA new scheme for calculating mineral end members with reference to clinopyroxene and garnetActa Geologica Sinica, Vol. 5, No. 2, June pp. 191-196GlobalMineralogy, Garnet
DS1991-1932
1991
Yang JianminZhou Xiouzhong, Huang Yunhui, Qin Shuying, Gao Yan, Yang JianminTypes, typomorphic characteristics of garnet from kimberlites in Shandong and Liaoning and its relationship with diamond.*CHIYanshi Kuangwuxue Zazhi (Acta Petrologica et Mineralogica)*CHI, Vol. 10, No. 3, August pp. 252-264ChinaPetrology, Garnets from kimberlites
DS1992-1716
1992
Yang RuiyingYang Ruiying, Yuan CaoA preliminary study on the trace element geochemistry of ultramafic inclusions in the eastern part of Lianoning-Jilin ChinaInternational Symposium Cenozoic Volcanic Rocks Deep seated xenoliths China and its, Abstracts pp. 103-104ChinaGeochemistry, Ultramafic
DS1984-0269
1984
Yang Yong FuFan liangming, Yang Yong Fu, Wen LuUltra violet photographs and spectral characteristics of mixed type diamonds in a kimberlite tube inChina. *CHIActa Petrologica Mineralogica Et Analytica *CHI, Vol. 3, No. 4, (12) pp. 339-345ChinaDiamond Morphology
DS1992-1717
1992
Yang YuYang Yu, Morse, S.A.Age and cooling history of the Kiglapait Intrusion from an 40Ar /39ArstudyGeochimica et Cosmochimica Acta, Vol. 56, No. 6, June, pp. 2471-2485Quebec, Labrador, UngavaGeochronology, Layered intrusions
DS1990-1427
1990
Yang ZiyuenSu Weijun, Yang ZiyuenVaotite- a new gemstone from Baiyun Ebo inner MongoliaInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 688-689ChinaCarbonatite, Mineralogy -vaolite
DS1986-0882
1986
Yang ZunyiYang Zunyi, Cheng Yuqi, Wang HongzhenThe geology of ChinaClarendon Press, Oxford, ChinaBlank
DS1998-1651
1998
YanginZuev, V.M., Bezborodov, S.M., Chyerny, S.D., YanginThe structures which control the location of kimberlites of Middle-Markinsky region.7th International Kimberlite Conference Abstract, pp. 1031-3.Russia, Siberia, YakutiaStructure, tectonics, Deposit - Botuibinskaya, Nyurbinskaya
DS2000-0771
2000
YanginPokhilenko, N.P., Sobolev, N.V., Chernyi, S.D., YanginPyropes and chromites from kimberlites in the Nakyn Field, and Snipe Lake (Slave River region) Evidence...Doklady Academy of Sciences, Vol. 372, No. 4, May-June pp. 638-42.Northwest Territories, Russia, YakutiaLithosphere - structure, Deposit - Nakyn, Snipe Lake
DS1995-2097
1995
Yangin, VV.Yangin, VV.Laws of structural control of localization of kimberlite pipes in the Daldyn field from CDPM data.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 672-674.Russia, YakutiaStructure, Deposit -Daldyn
DS1983-0002
1983
Yangin, YU.T.Afanasev, B.P., Yangin, YU.T.Buried Primary Dispersion Streams of Kimberlite Bodies in The MalobuTo bin Skii Region.Geology And Geophysics, Vol. 24, No. 6, PP. 76-81.Russia, YakutiaGeochemistry, Sampling
DS1995-2098
1995
YangshenYangshen, Shi, Huafu, L., Valin, Z.C.Paleozoic plate tectonic evolution of the Tarim and western Tianshanregions, western China.International Geology Review, Vol. 36, No. 11, Nov. pp. 1058-1066.ChinaTectonics
DS200412-2175
2004
Yangsong, D.Yangsong, D., Hyunkoo, L., Xinlong, Q.Underplating of Mesozoic mantle derived magmas in Tongling, Anhui Province: evidence from megacrysts and xenoliths.Acta Geologica Sinica, Vol. 78, 1, pp. 131-136.China, AnhuiMagmatism
DS200712-0980
2006
Yanhe, L.Shihong, T., Tiping, D., Jingwen, M., Yanhe, L., Zhongxin, Y.S, C, O, H isotope dat a and noble gas studies of the Maoniuping LREE deposit, Sichuan Province, China: a mantle connection for mineralization.Acta Geologica Sinica, Vol. 80, 4, pp. 540-549.ChinaAlkaline rocks, rare earths, carbonatite
DS1970-0673
1973
Yanitskii, I.N.Eremeev, A.N., Sokolov, V.A., Solovov, A.P., Yanitskii, I.N.Application of Helium Surveying to Structural Mapping and Ore Deposit Forecasting.International GEOCHEM. Exploration Symposium 4TH., PP. 183-192.RussiaKimberlite, Geophysics
DS1991-1902
1991
Yannan BaoYannan Bao, Matsyuk, S.S.Composition of kimberlite spinels from Shangtung and Liaoning Provinces inChinaGeochemistry International, Vol. 28, No. 9, pp. 89-95ChinaGeochemistry, kimberlite spinels
DS2002-0014
2002
Yano, M.Akogi, M., Yano, M., Suzuki, T., Koijitani, H.Phase transformation in calcium bearing silicates at high pressures and high temperatures.18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.76.MantleUHP mineralogy - diopside, hedenbergite
DS1996-1361
1996
Yanova, E.O.Staritskii, Yu.G., Kochkin, G.B., Yanova, E.O.Regularities of spatial distribution of the major minerals in the Russian Platform coverGeology of Ore Deposits, Vol. 38, No. 1, pp. 66-77RussiaModels, genesis, Uranium, Rare earths
DS2003-0973
2003
Yanovskaya, T.B.Mordvinova, V.V., Kozhevnikov, V.M., Yanovskaya, T.B., Treussov, A.V.Baikal rift zone: the effect of mantle plumes on older structureTectonophysics, Vol. 371, 1-4, pp. 153-173.Russia, BaikalTectonics, rifting
DS2003-1131
2003
Yanovskaya, T.B.Rasskazov, S.V., Logachev, N.A., Kozhevnikov, V.M., Yanovskaya, T.B.Multistage dynamics of the upper mantle in eastern Asia: relationships betweenDoklady Earth Sciences, Vol. 390, 4, pp. 492-6.Asia, RussiaGeodynamics, Tectonics
DS2003-1525
2003
Yanovskaya, T.B.Yanovskaya, T.B., Kozhevnikov, V.M.3D S wave velocity pattern in the upper mantle beneath the continent of Asia fromPhysics of the Earth and Planetary Interiors, Vol. 138, 3-4, pp. 263-278.ChinaGeophysics - seismics
DS200412-1364
2003
Yanovskaya, T.B.Mordvinova, V.V., Kozhevnikov, V.M., Yanovskaya, T.B., Treussov, A.V.Baikal rift zone: the effect of mantle plumes on older structure.Tectonophysics, Vol. 371, 1-4, pp. 153-173.Russia, BaikalTectonics, rifting
DS200412-1630
2003
Yanovskaya, T.B.Rasskazov, S.V., Logachev, N.A., Kozhevnikov, V.M., Yanovskaya, T.B.Multistage dynamics of the upper mantle in eastern Asia: relationships between wandering volcanism and low velocity anomalies.Doklady Earth Sciences, Vol. 390, 4, pp. 492-6.Asia, RussiaGeodynamics Tectonics
DS200412-2176
2003
Yanovskaya, T.B.Yanovskaya, T.B., Kozhevnikov, V.M.3D S wave velocity pattern in the upper mantle beneath the continent of Asia from rayleigh wave data.Physics of the Earth and Planetary Interiors, Vol. 138, 3-4, pp. 263-278.ChinaGeophysics - seismics
DS201312-0273
2013
Yanovskaya, T.B.Foulger, G.R., Panza, G.F., Artemieva, I.M., Bastow, I.D., Cammarano, F., Evans, J.R., Hamilton, W.B., Julian, B.R., Lustrino, M., Thybo, H., Yanovskaya, T.B.Caveat on tomographic images.Terra Nova, Vol. 25, 4, pp. 259-281.MantleSeismic tomography, geodynamics
DS200912-0063
2009
Yantao, H.Bonadiman, C., Yantao, H., Coltorti, M., Dallai, L., Faccini, B., Huang, YU., Xia, Q.Water content of pyroxenes in intraplate lithospheric mantle.European Journal of Mineralogy, Vol. 21, 3, June pp. 637-647.MantleWater
DS2001-0005
2001
YanyginAfanasev, V.P., Zinchuk, Pkhilenko, Krivonos, YanyginKarst role in the formation of diamond placers of the Muno Markhinskii interfluve Yakutsk diamond provinceGeol. Ore Depos., Vol. 43, No. 3, pp. 234-8.Russia, SiberiaAlluvials, Geomorphology
DS1998-0244
1998
Yanygin, Ju.T.Cherny, S.D., Fomin, A.S., Yanygin, Ju.T., Banzeruk, V.Geology and composition of the Nakyn field kimberlite pipes and diamond properties (Yakutia).7th International Kimberlite Conference Abstract, pp. 147-148.Russia, YakutiaPetrology, Deposit - Botuobinskaya, Nurbinskaya
DS200412-1561
2003
Yanygin, Y.T.Pokhilenko, N.P., Agashev, A.M., McDonald, J.A., Sobolev, N.V., Mityukhin, S.I., Vavilov, M.A., Yanygin, Y.T.Kimberlites of the Nakyn field, Siberia and the Snap Lake King Lake dyke system, Slave Craton, Canada: a new variety of kimberli8 IKC Program, Session 7, POSTER abstractCanada, Northwest TerritoriesKimberlite petrogenesis Deposit - Snap Lake, King Lake
DS1983-0593
1983
Yanygin, YU.T.Taranenko, V.I., Prokopchuk, B.I., Yanygin, YU.T., Shapovalova.Paleogeomorphological Environment of Diamond Placer Genesis at the Southeastern Slope of the Tunguska Syneclise During The Late Paleozoic.Geomorfologiya., 1983 (2), PP. 48-53.RussiaGeomorphology, Alluvial Placers
DS202204-0544
2022
YanZurevinski, S.Weng, Q., YanZurevinski, S., Wu, D.g, W-B., Niu, H-C., Li, N-B., Mitchell, R.H.Formation of the Maoniuping giant REE deposit: constraints from mineralogy and in situ bastnasite U-Pb geochronology.American Mineralogist, Vol. 107, pp. 282-293. pdfChinadeposit - Maoiuping REE

Abstract: The time and processes of hydrothermal mineralization are long-standing problems in geology. This work addresses these questions with reference to the Maoniuping giant rare earth elements (REE) deposit (southwest China), which has rare earth oxides (REO) reserves of 3.17 million tons with an average grade of 2.95 wt%. Bastnäsite is the dominant economic mineral, occurring as four distinct paragenetic types in the Maoniuping syenite-carbonatite complex: (1) primary euhedral bastnäsite (type-A) in syenite, with isolated melt inclusions; (2) macro-crystalline tabular euhedral bastnäsite (type-B) in pegmatitic dikes, with a diverse variety of fluid inclusions; (3) fine-grained, anhedral veinlet-disseminated bastnäsite (type-C) in syenite; and (4) coarse-grained anhedral bastnäsite (type-D) in carbonatite dikes, occurring as veinlets or interstitial to calcite, fluorite, and barite. From the paragenetic and compositional variations, it is inferred that type-A bastnäsite is of primary magmatic origin, whereas the other three types have characteristics of hydrothermal origins. In situ LA-ICP-MS U-Pb geochronology of the four types of bastnäsite results in lower intercept ages of 28.2 ± 0.5 Ma (n = 95, MSWD = 5.10), 27.8 ± 0.4 Ma (n = 43, MSWD = 0.73), 26.8 ± 0.7 Ma (n = 50, MSWD = 0.83), and 25.8 ± 0.7 Ma (n = 55, MSWD = 1.70), respectively, which are consistent with the weighted average 206Pb/238U and 208Pb/232Th ages by 207Pb-correction method. Compositional variations of clinopyroxene and apatite from the associated syenite, pegmatitic and carbonatitic dikes indicate a genetic relationship of the Maoniuping alkaline complex. The compositions of clinopyroxene range from Ae44-67Di14-18Hd17-41 in pegmatitic dikes, Ae43-66Di6-20Hd21-38 in carbonatitic dikes to Ae68-90Di0-3Hd10-30 in syenite. Apatites in the pegmatitic and carbonatitic dikes have similar compositions with higher F, total REE, and Sr, and lower CaO contents than those in the syenite, which suggests a cogenetic origin for the associated pegmatite and carbonatite. Clinopyroxene and apatite compositions suggest that the pegmatitic melt might differentiate directly from the initial carbonatitic melt rather than the syenitic magma. The bastnäsite U-Pb geochronology and minerals data indicate continuous magmatic-hydrothermal evolution for the REE mineralization in the Maoniuping alkaline complex.
DS201802-0268
2018
Yao, C.Sun, W-d., Hawkesworth, C.J., Yao, C., Zhang, C-C., Huang, R.f., Liu, X., Sun, X-L, Ireland, T., Song, M-s., Ling, M-x., Ding, X., Zhang, Z-f., Fan, W-m., Wu, Z-q.Carbonated mantle domains at the base of the Earth's transition zone.Chemical Geology, Vol. 478, pp. 69-75.Mantlecarbonatite

Abstract: The oxygen fugacity of the upper mantle is 3-4 orders of magnitude higher than that of the lower mantle and this has been attributed to Fe2 + disproportionating into Fe3 + plus Fe0 at pressures > 24 GPa. The upper mantle might therefore have been expected to have evolved to more oxidizing compositions through geological time, but it appears that the oxygen fugacity of the upper mantle has remained constant for the last 3.5 billion years. Thus, it indicates that the mantle has been actively buffered from the accumulation of Fe3 +, and that this is linked to oxidation of diamond to carbonate coupled with reduction of Fe3 + to Fe2 +. When subducted plates penetrate into the lower mantle, compensational upwelling transports bridgmanite into the transition zone, where it breaks down to ringwoodite and majorite, releasing the ferric iron. The system returns to equilibrium through oxidation of diamond. Early in Earth history, diamond may have been enriched at the base of the transition zone in the Magma Ocean, because it is denser than peridotite melts at depths shallower than 660 km, and it is more buoyant below. Ongoing oxidation of diamond forms carbonate, leading to relatively high carbonate concentrations in the source of ocean island basalts.
DS200812-0022
2008
Yao, D.B.Allialy, M.E., Djro, S.C., Yavouba, C., Konamelan, A.N., Pothin, K.B., Yao, D.B., Yobou, R.Comparative geochemistry of Seguela kimberlites, South Africa Group II kimberlites and other worldwide kimberlites.9IKC.com, 3p. extended abstractAfrica, West Africa, Ivory CoastDeposit - Bobi, Toubabouko
DS201212-0127
2013
Yao, H.Cheng, C., Chen, L., Yao, H., Jiang, M., Wang, B.Distinct variations of crustal shear wave velocity structure and radial anisotropy beneath the North Chin a Craton and tectonic implications.Gondwana Research, Vol. 23, 1, pp. 25-38.ChinaTomography
DS202004-0502
2020
Yao, J.Cawood, P.A., Wang, W., Zhao, T., Xu, Y., Mulder, J.A., Pisarevsky, S.A., Zhang, L., Gan, C., He, H., Liu, H., Qi, L., Wang, Y., Yao, J., Zhao, G., Zhou, M-F., Zi, J-W.Deconstructing south China and consequences for reconstructing Nuna and Rodinia.Earth-Science Reviews, in press available, 70p. PdfChinatectonics

Abstract: Contrasting models for internal and external locations of South China within the Nuna and Rodinia supercontinents can be resolved when the current lithotectonic associations of Mesoproterozoic and older rocks units that constitute the craton are redefined into four lithotectonic domains: Kongling, Kunming-Hainan, Wuyi, and Coastal. The Kongling and Kunming-Hainan domains are characterized by isolated Archean to early Paleoproterozoic rock units and events and crop out in northern and southern South China, respectively. The Kunming-Hainan Domain is preserved in three spatially separated regions at Kunming (southwestern South China), along the Ailaoshan shear zone, and within Hainan Island. Both domains were affected by late Paleoproterozoic tectonothermal events, indicating their likely juxtaposition by this time to form the proto-Yangtze Block. Late Paleoproterozoic and Mesoproterozoic sedimentary and igneous rock units developed on the proto-Yangtze Block, especially in its southern portions, and help link the rock units that formed along the shear zone at Ailaoshan and on Hainan Island into a single, spatially unified unit prior to Paleozoic to Cenozoic structural disaggregation and translation. The Wuyi Domain consists of late Paleoproterozoic rock units within a NE-SW trending, fault-bounded block in eastern South China. The Coastal Domain lies east of the Wuyi domain and is inferred to constitute a structurally separate block. Basement to the domain is not exposed, but zircon Hf model ages from Mesozoic granites suggest Mesoproterozoic basement at depth. The Archean to Paleoproterozoic tectonothermal record of the Kongling and Kunming-Hainan domains corresponds closely with that of NW Laurentia, suggesting all were linked, probably in association with assembly and subsequent partial fragmentation of the Nuna supercontinent. Furthermore, the age and character of Mesoproterozoic magmatism and detrital zircon signature of sedimentary rocks in the proto-Yangtze Block matches well with western Laurentia and eastern Australia-Antarctica. In particular, the detrital zircon signature of late Paleoproterozoic to early Mesoproterozoic sedimentary units in the block (e.g. Dongchuan Group) share a similar age spectrum with the Wernecke Supergroup of northwest Laurentia. This, together with similarities in the type and age of Fe-Cu mineralization in the domain with that in eastern Australia-Antarctica, especially northeast Australia, suggests a location adjacent to northwest Laurentia, southern Siberia, and northeast Australia within the Nuna supercontinent. The timing and character of late Paleoproterozoic magmatic activity in the Wuyi domain along with age of detrital zircons in associated sedimentary rocks matches the record of northern India. During rifting between Australia-Antarctica and Laurentia in the late Mesoproterozoic, the proto-Yangtze Block remained linked to northeast Australia. During accretionary orogenesis in the early Neoproterozoic, the proto-Yangtze Block assembled with the Wuyi Domain along the northern margin of India. The Coastal domain likely accreted at this time forming the South China Craton. Displacement of the Hainan and Ailaoshan assemblages from southwest of the Kunming assemblage likely occurred in the Cenozoic with the activation of the Ailaoshan-Red River fault system but could have begun in the early to mid-Paleozoic based on evidence for tectonothermal events in the Hainan assemblage.
DS201610-1882
2016
Yao, L.Le Roux, V., Nielsen, S.G., Sun, C., Yao, L.Dating layered websterite formation in the lithospheric mantle.Earth and Planetary Science Letters, Vol. 454, pp. 103-112.Mantle, Africa, MoroccoMelting

Abstract: Pyroxenites are often documented among exhumed mantle rocks, and can be found in most tectonic environments, from supra-subduction to sub-continental and sub-oceanic mantle. In particular, websterites, i.e. orthopyroxene-clinopyroxene bearing pyroxenites, are found in parallel layers in most orogenic and ophiolitic peridotites. Their formation is often ascribed to melt infiltration and melt-rock reaction processes accompanied by variable amount of deformation. One outstanding question is whether the ubiquitous occurrence of layered websterites in exhumed rocks is generally linked to the exhumation process or truly represents large-scale melt infiltration processes at depth prior to exhumation. These two hypotheses can be distinguished by comparing the exhumation and formation ages of the websterites. However, determination of the layered websterite formation age is challenging. Here we present a novel approach to constrain the formation age of websterite layers using samples from the Lherz massif (France), where layered websterites and lherzolites have formed through melt-rock reaction. By combining high-resolution REE variations, isotope model ages, and diffusive re-equilibration timescales using REE closure temperatures across the websterite layers, we constrain a minimum age and a maximum age for the formation of layered websterites. We show that layered websterites in Lherz formed 1,500-1,800 Ma ago, and are thus clearly disconnected from the process of exhumation at 104 Ma. Multiple generations of layered websterites commonly found in ultramafic massifs, along with the evidence for ancient melt-rock reaction in Lherz, indicate that melt-rock reactions can happen episodically or continuously in the mantle and that layered websterites found in exhumed mantle rocks record ubiquitous melt infiltration processes in the mantle.
DS200512-0659
2005
Yao, N.Lu, P.J., Yao, N., So, J.F., Harlow, G.E., Lu, J.F., Wang, G.F., Chaikin, P.M.The earliest use of corundum and diamond in prehistoric China.Archeometry, Vol. 47,1, Feb. pp. 1-12. Blackwell PublicationsChinaHistory
DS200812-1247
2008
Yao, P.Wen, B., Zhao, J., Bucknum, M.J., Yao, P., Li, T.First principles studies of diamond polytypes.Diamond and Related Materials, Vol. 17, 3, pp. 356-364.TechnologyDiamond crystallography - simulation
DS1998-1611
1998
Yao, S.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
DS201904-0763
2019
Yao, W.Olierook, H.K.H., Agangi, A., Plavsa, D., Reddy, S.M., Yao, W., Clark, C., Occipinti, S.A., Kylander-Clark, A.R.C.Neoproterozoic hydrothermal activity in the west Australian craton related to Rodinia assembly or breakup?Gondwana Research, Vol 68, 1, pp. 1-12.Australiacraton

Abstract: The timing of final assembly and initiation of subsequent rifting of Rodinia is disputed. New rutile ages (913?±?9?Ma, 900?±?8?Ma and 873?±?3?Ma) and published zircon, monazite, titanite, biotite, muscovite and xenotime geochronology from the Capricorn Orogen (West Australian Craton) reveal a significant early Neoproterozoic event characterized by very low to low metamorphic grade, abundant metasomatism, minor leucogranitic and pegmatitic magmatism and NW-SE fault reactivation episodes between ca. 955 and 830?Ma. Collectively, these are termed the ca. 955-830?Ma Kuparr Tectonic Event. An age range of ca. 955-830?Ma is concomitant with the final stages of Rodinia assembly and the initial stages of its attempted breakup. Very low- to low-grade metamorphic and structural geological evidence favor a distal north-south compressional regime as the driver for hydrothermal activity during ca. 955-830?Ma. Nearby continental collision or accretion from the west (e.g., South China and/or Tarim) are ruled out. The cessation of metasomatism and magmatism in the West Australian Craton after ca. 830?Ma is concomitant with the emplacement of the Gairdner-Amata dyke swarm and associated magmatic activity in South China and Laurentia, the inception of the Adelaide Rift Complex and the deposition of the Centralian Superbasin. We posit that the cessation of hydrothermal activity in the Capricorn Orogen was caused by a tectonic switch from compressional to extensional at ca. 830?Ma. Magmatic and hydrothermal fluids were transferred away from the Capricorn Orogen to the incipient Adelaide Rift Complex, terminating metasomatism in the West Australian Craton. Ultimately, the Kuparr Tectonic Event marked the final stages of Rodinia assembly and its cessation marks the initial stages of its attempted breakup.
DS202202-0219
2022
Yao, Y.Tan, W., Qin, X., Liu, J., Zhou, M-F., He, H., Yang, C.Y., Huang, J., Zhu, J., Yao, Y., Cudahy, T.Feasibility of visible short-wave infrared reflectance spectroscopy to characterize regolith-hosted rare earth element mineralization.Economic Geology, Vol. 117, 3, pp. 485-494.Chinadeposit - Renju

Abstract: Regolith-hosted rare earth element (REE) deposits predominate global resources of heavy REEs. Regoliths are underlain by various types of igneous rocks and do not always host economically valuable deposits. Thus a feasible and convenient method is desired to identify REE mineralization in a particular regolith. This study presents a detailed visible short-wave infrared reflectance (VSWIR) spectroscopic study of the Renju regolith-hosted REE deposit, South China, to provide diagnostic parameters for targeting REE orebodies in regoliths. The results show that the spectral parameters, M794_2nd and M800_2nd, derived from the VSWIR absorption of Nd3+ at approximately 800 nm, can be effectively used to estimate the total REE concentrations in regolith profiles. M1396_2nd/M1910_2nd ratios can serve as proxies to evaluate weathering intensities in a regolith. Abrupt changes of specific spectral features related to mineral abundances, chemical compositions, and weathering intensities can be correlated with variations of protolith that formed a regolith. These VSWIR proxies are robust and can be used for exploration of regolith-hosted REE deposits.
DS201112-1136
2011
Yao, Z.Ye, L., Li, J., Tseng, T-L., Yao, Z.A stagnant slab in a water bearing transition zone beneath northeast China: implications from regional SH waveform modelling.Geophysical Journal International, Vol. 186, 2, pp. 706-710.ChinaSubduction
DS201112-1137
2011
Yao, Z.Ye, L., Tseng, T-L., Yao, Z.A stagnant slab in a water bearing mantle transition zone beneath northeast China: implications from regional SH waveform modelling.Geophysical Journal International, In press available,ChinaSubduction
DS201811-2621
2018
Yao, Z.Yang, H., Xiao, J., Yao, Z., Zhang, X., Younus, F., Melnik, R., Wen, B.Homogeneous and heterogenous dislocation nucleation in diamond.Diamond & Related Materials, Vol. 88, pp. 110-117.Mantlediamond morphology

Abstract: Dislocation nucleation plays a key role in plastic deformation of diamond crystal. In this paper, homogeneous and heterogeneous nucleation nature for diamond glide set dislocation and shuffle set dislocation is studied by combining molecular dynamics method and continuum mechanics models. Our results show that although heterogeneous dislocation nucleation can decrease its activation energy, the activation energy at 0?GPa for diamond heterogeneous nucleation is still in the range of 100?eV. For glide set and shuffle set homogeneous nucleation, their critical nucleation shear stress approaches to diamond's ideal shear strength which implies that those dislocations do not nucleate before diamond structural instability only by a purely shearing manner. While for glide set and shuffle set heterogeneous nucleation, their critical nucleation shear stresses are 28.9?GPa and 48.2?GPa, these values are less than diamond's ideal shear strength which implies that these dislocations may be nucleated heterogeneously under certain shear stress condition. In addition, our results also indicate there exists a deformation mode transformation for diamond deformation behavior at strain rate of 10?3/s. Our results provide a new insight into diamond dislocation nucleation and deformation.
DS202205-0677
2022
Yao, Z-S.Chen, C., Yao, Z-S., Yan Wang, C.Partitioning behaviours of cobalt and manganese along diverse melting paths of peridotitic and MORB-like pyroxenite mantle.Journal of Petrology, Vol. 63, 4, 10.1093/perology/egac021Mantleperidotite

Abstract: The Co, Mn, Fe, and Ni contents of olivine phenocrysts and host basalts are sensitive to source mantle lithology, which suggests they may be used to constrain the processes of mantle melting and identify basalts formed from non-peridotitic (i.e. pyroxenitic) mantle sources. Here, we use a new comprehensive, forward model involving multiple parameters to simulate partitioning of Co and Mn during partial melting of the mantle in different tectonic settings: (1) polybaric continuous melting of peridotite mantle in mid-ocean ridges can generate melts that show decreasing Co and Mn with increasing degrees of melting so that the mid-ocean ridge basalts (MORBs) contain ~39-84 ?g/g Co and?~900-1600 ?g/g Mn; (2) flux-melting of the mantle wedge in subduction zones tends to produce a melt that has Co increasing from ~24 to 55 ?g/g and Mn from ~500 to 1110 ?g/g with increasing temperature; (3) melts produced by isobaric melting of the subcontinental lithospheric mantle are also sensitive to increasing temperature and have ~35-160 ?g/g Co and ~800-2600 ?g/g Mn; (4) decompression melting of peridotite related to the mantle plume generates melts containing ~45-140 ?g/g Co and?~1000-2000 ?g/g Mn, and the abundances of these metals decrease with increasing degrees of melting; and (5) partitioning behaviors of Co, Mn, and Ni during decompression melting of MORB-like pyroxenite contrast with those during decompression melting of peridotite due to the different mineralogy and compositions in mantle lithologies, and the MORB-like pyroxenite-derived melt is metal-poor with ~25-60 ?g/g Co, ~290-1600 ?g/g Mn, and?~160-340 ?g/g Ni. Although high-Ni, low-Mn forsteritic olivine phenocrysts and high melt Fe/Mn ratio have been proposed as diagnostic indicators of pyroxenitic components in the mantle, our models show that these features can be also generated by melting of peridotite at greater depth (i.e. a high pressure and temperature). To quantify the effect of high-pressure melting of peridotite on these diagnostic indicators, we modeled the correlations of melt Fe/Mn and olivine Co, Mn, and Ni contents with melting depth along the decompression melting path of a thermal plume. When Fe/Mn ratios of basalts and/or compositions of olivine phenocrysts deviate significantly from our modeled correlation lines, high-pressure melting of peridotite cannot explain these data, and the existence of pyroxenitic component in the mantle source is likely required. The pyroxenite-derived melt is modeled to be Ni-poor, but mixing with a peridotite-derived melt can strongly increase the partition coefficient of Ni between olivine and mixed melt, resulting in the generation of high-Ni olivine phenocrysts in plume-associated magmatic suites.
DS1992-0318
1992
Yao ShaodeCui Guozhi, Yao ShaodeTentative study on the principle of radio resonant seperation of Kimberlite and its wall rockInternational Journal of Mineral Processing, Vol. 34, No. 1-2, January pp. 177-183ChinaMineral processing, Kimberlite
DS1991-1903
1991
Yaoling NiuYaoling Niu, Batiza, R.DENSCAL: a program for calculating densities of silicate melts and Mantle minerals as a function of pressure, temperature, and composition in meltingrangeComputers and Geosciences, Vol. 17, No. 5, pp. 679-688GlobalComputer, Program -DENSCAL -silicates
DS1991-1904
1991
Yaoling NiuYaoling Niu, Batiza, R.In situ densities of Mid Ocean Ridge Basalt (MORB) melts and residual mantle: implications for bouyancy forces beneath mid-Ocean ridgesJournal of Geology, Vol. 99, pp. 767-775GlobalMantle, Mid Ocean Ridge Basalt (MORB), tectonics
DS201511-1886
2015
Yap, C.M.Tarum, A., Lee, S.J., Yap, C.M., Finkelstein, K.D., Misra, D.S.Impact of impurities and crystal defects on the performance of CVD diamond detectors.Diamond and Related Materials, in press available, 6p.TechnologySynthetics - Radiation detectors

Abstract: Radiation detectors based on diamond are highly favored for particle physics research due to the superior radiation hardness. In this work, we investigate the influence of impurities and crystalline imperfections on the charge collection efficiency (CCE) of single crystal diamond. Seventeen (17) ultra-low fluorescent diamond samples grown by microwave plasma chemical vapor deposition method from IIa Technologies PTE LTD are pre-selected for this study. The measured CCE of all samples using 241Am (?-particles) as ionizing source are analyzed together with the concentration of trace impurities and crystalline imperfection in the crystal. The amounts of impurities are quantified from integrated fluorescence intensity arising from the nitrogen vacancies (NV) created during different CVD growth process conditions. The crystal imperfections are assessed by X-ray rocking curves from X-ray topography images obtained at the Cornell High Energy Synchrotron Source. The CCE decays rapidly as the intensity of NV (INV), phonon sideband approaches that of diamond 2nd order Raman peak which follows the relation: View the MathML sourceCCEINV=100/1+INV1.052. The energy resolution, ?E/E (ratio of the energy spectrum width to the most probable peak) highly correlates with broader rocking curve width distribution. Prime novelty statement: This work provides an understanding on the most important factors that contribute to degradation of charge collection efficiency (CCE) in diamond based detectors and sensors. The CCE decays rapidly as the intensity of nitrogen vacancy phonon sideband approaches that of diamond 2nd order Raman peak which follows the relation: View the MathML sourceCCEINV=100/1+INV1.052. The energy resolution, that is the ratio of the energy spectrum width to the most probable peak, highly correlates with broader X-ray rocking curve width distribution.
DS201511-1889
2015
Yap, C.M.Yap, C.M., Tarum, A., Xiao, S., Misra, D.S.MPCVD growth of 13 C-enriched diamond single crystals with nitrogen addition.Diamond and Related Materials, in press available, 29p.TechnologySynthetics - nitrogen

Abstract: This study describes the growth of 13C-enriched (100)-oriented diamond single crystals by the MPCVD (microwave plasma chemical vapour deposition) process. All crystals are at least 6 × 6 mm2 in area and 0.5-1.0 mm in thickness. The samples with nominal 13C percentages (R = [13C] / [13C + 12C]) of 0.011 (natural abundance), 0.10, 0.21, 0.24 and 0.34 were obtained by controlling the flow of the carbon-13 and carbon-12 methane feed gases. To obtain thicker and near-colourless quality 13C-enriched diamond, 190 ppm of nitrogen was added into the gas mixture. The shift towards lower frequency in the Raman peak positions and decrease in the thermal conductivities of the near-colourless crystals with increasing 13C percentages are similar to previous studies of isotopically-controlled diamond grown with no nitrogen additive. The images of the structural defects associated with 13C-enrichment obtained by spatially-resolved X-ray rocking curve measurement show distinct patterned structures that runs parallel to the < 100 > direction. Moreover, the broadening in the line width of the nuclear magnetic resonance (NMR) peak from sp313C correlates with increasing R. We also expand the study by injecting 500 ppm of nitrogen. Higher nitrogen concentration leads to the formation of brown crystals. The brown crystals show far greater 13C NMR peak intensity than the near-colourless. This suggests that paramagnetic nitrogen impurities in the brown crystals hasten the spin-lattice relaxation time of the 13C nuclear spin that resulted in higher intensity. The isotopic splitting observed for the localized vibrational mode of the NVH0 defect in brown crystals is attributed to the co-existence of both the 13C (3114.2 cm? 1) and 12C (3123.5 cm? 1). Unlike the isotopic splitting observed for NVH0 defect, the peak position of the Ns+ defect shifts towards lower frequency as R increases. Not only have we demonstrate the growth of bigger isotopically-controlled diamond single crystals, the results shown here have provided a framework to further investigate the interplay between 13C atoms and nitrogen impurity.
DS2002-1243
2002
YapaskurtPerchuk, L.L., Safonov, O.G., Yapaskurt, BartonCrystal melt equilibration temperatures involving potassium bearing clinopyroxene as indicator of mantle derived ultrahighLithos, Vol.60, pp. 89-111.MantleMelting - potassic liquids, an analytical review
DS1995-1479
1995
Yapaskurt, V.O.Perchuk, L.L., Yapaskurt, V.O., Okay, A.Comparative petrology of diamond bearing complexesPetrology, Vol. 3, No. 3, May-June pp. 238-277.RussiaPetrology, Diamond complexes
DS2002-1244
2002
Yapaskurt, V.O.Perchuk, L.L., Safonov, O.G., Yapaskurt, V.O., BartonCrystal melt equilibration temperatures involving potassium bearing clinopyroxene as indicator of mantle derived ultrahighLithos, Vol. 60, No. 3-4, Feb. pp. 89-111.MantleAnalytical review - potassic liquids
DS2003-0111
2003
Yapaskurt, V.O.Bindi, L., Safonov, O.G., Yapaskurt, V.O., Perchuk, L.L., Menchetti, S.Ultrapotassic clinopyroxene from the Kumdy Kol microdiamond mine, KokchetavAmerican Mineralogist, Vol. 88, 2-3, Feb.March pp. 464-8.Russia, KazakhstanMineral chemistry, Kokchetav Complex
DS200812-0882
2008
Yapaskurt, V.O.Perchuk, A.L., Yapaskurt, V.O., Davydova, V.V.Melt inclusions in eclogite garnet: experimental study of natural processes.Russian Geology and Geophysics, Vol. 49, 4, pp. 310-312.Canada, YukonEclogite - melting
DS200912-0658
2009
Yapaskurt, V.O.Safonov, O.G., Perchuk, L.L., Yapaskurt, V.O., Litvin, Yu.A.Immiscibility of carbonate silicate and chloride carbonate melts in the kimberlite CaCO3 Na2Co3 KCL system at 4.8 GPa.Doklady Earth Sciences, Vol. 424, 1, pp. 142-146.TechnologyGeochemistry
DS201012-0573
2009
Yapaskurt, V.O.Perchuk, A.L., Davydova, V.V., Burchard, M., Maresch, W.V., Schertl, H.P., Yapaskurt, V.O., Safonov, O.G.Modification of mineral inclusions in garnet under high pressure conditions: experimental simulation and application to carbonate silicate rocks of KokchetetavRussian Geology and Geophysics, Vol. 50, 12, pp. 1153-1168.RussiaMineralogy
DS201412-0672
2013
Yapaskurt, V.O.Perchuk, A.L., Shur, M.Yu., Yapaskurt, V.O., Podgornova, S.T.Experimental modeling of mantle metasomatism coupled with eclogitization of crustal material in a subduction zone.Petrology, Vol. 21, 6, pp. 579-598.MantleSubduction
DS201505-0249
2015
Yapaskurt, V.O.Belogub, E.V., Krivovichev, S.V., Pekov, I.V., Kuznetsov, A.M., Yapaskurt, V.O., Kitlyarov, V.A., Chukanov, N.V., Belakoviskiy, D.I.Nickelpicromerite, K2Ni(SO4)2*6H2O, a new picromerite group mineral from Slyudorudnik, South Urals, Russia.Mineralogy and Petrology, Vol. 109, 2, pp. 143-152.Russia, UralsMineralogy

Abstract: A new picromerite-group mineral, nickelpicromerite, K2Ni(SO4)2 - 6H2O (IMA 2012-053), was found at the Vein #169 of the Ufaley quartz deposit, near the town of Slyudorudnik, Kyshtym District, Chelyabinsk area, South Urals, Russia. It is a supergene mineral that occurs, with gypsum and goethite, in the fractures of slightly weathered actinolite-talc schist containing partially vermiculitized biotite and partially altered sulfides: pyrrhotite, pentlandite, millerite, pyrite and marcasite. Nickelpicromerite forms equant to short prismatic or tabular crystals up to 0.07 mm in size and anhedral grains up to 0.5 mm across, their clusters or crusts up to 1 mm. Nickelpicromerite is light greenish blue. Lustre is vitreous. Mohs hardness is 2-2½. Cleavage is distinct, parallel to {10-2}. Dmeas is 2.20(2), Dcalc is 2.22 g cm?3. Nickelpicromerite is optically biaxial (+), ? = 1.486(2), ? = 1.489(2), ? = 1.494(2), 2Vmeas =75(10)°, 2Vcalc =76°. The chemical composition (wt.%, electron-microprobe data) is: K2O 20.93, MgO 0.38, FeO 0.07, NiO 16.76, SO3 37.20, H2O (calc.) 24.66, total 100.00. The empirical formula, calculated based on 14 O, is: K1.93Mg0.04Ni0.98S2.02O8.05(H2O)5.95. Nickelpicromerite is monoclinic, P21/c, a = 6.1310(7), b = 12.1863(14), c = 9.0076(10) Å, ? = 105.045(2)°, V = 649.9(1) Å3, Z = 2. Eight strongest reflections of the powder XRD pattern are [d,Å-I(hkl)]: 5.386--34(110); 4.312-46(002); 4.240-33(120); 4.085--100(012, 10-2); 3.685-85(031), 3.041-45(040, 112), 2.808-31(013, 20-2, 122), 2.368-34(13-3, 21-3, 033). Nickelpicromerite (single-crystal X-ray data, R = 0.028) is isostructural to other picromerite-group minerals and synthetic Tutton’s salts. Its crystal structure consists of [Ni(H2O)6]2+ octahedra linked to (SO4)2? tetrahedra via hydrogen bonds. K+ cations are coordinated by eight anions. Nickelpicromerite is the product of alteration of primary sulfide minerals and the reaction of the acid Ni-sulfate solutions with biotite.
DS201609-1729
2016
Yapaskurt, V.O.Lykova, I.S., Pekov, I.V., Chukanov, N.V., Belakovskiy, D.I., Yapaskurt, V.O., Zubkova, N.V., Britvin, S.N., Giester, G.Calciomurmanite a new mineral from the Lovozero and Khibiny alkaline complexes, Kola Peninsula.European Journal of Minerlogy, in press avaialbe 15p.RussiaMineralogy
DS201812-2861
2018
Yapaskurt, V.O.Perchuk, A.L., Yapaskurt, V.O., Zinovieva, N.G., Shur, M. Yu.Experimental evidence for opposite fluxes of sodium, potassium, and CO2 during glaucophane schist interaction with harzburgite and websterite in subduction zones.Petrology, Vol. 26, 6, pp. 599-616.Mantlemetasomatism

Abstract: This paper reports the results of high-pressure experimental modeling of interaction between glaucophane schist and harzburgite or websterite for the evaluation of the influence of mantle material on the input-output of components and character of metasomatic transformations at the crust-mantle boundary in the subduction zone. In all experiments, glaucophane schist (proxy for oceanic crust) containing volatile components (H2O and CO2) incorporated in hydrous minerals (amphiboles, phengite, and epidote) and calcite was loaded into the bottom of each capsule and overlain by mantle material. During the experiments at a temperature of 800°C and a pressure of 2.9 GPa, which correspond to the conditions of a hot subduction zone, the schist underwent partial (up to 10%) eclogitization with the formation of the anhydrous assemblage omphacite + garnet + quartz ± magnesite ± potassic phase. Carbonate and a potassic phase were formed only in the experiments with websterite in the upper layer. A reaction zone was formed at the base of the websterite layer, where newly formed omphacite, quartz, and orthopyroxene replaced in part initial pyroxenes. Orthopyroxene and phlogopite (or an unidentified potassic phase) were formed in the reaction zone at the base of the harzburgite layer; among the initial minerals, only orthopyroxene relicts were preserved. Above the reaction zones produced by diffusion metasomatism, new phases developed locally, mainly at grain boundaries: newly formed orthopyroxene and magnesite were observed in harzburgite, and omphacite and quartz, in websterite. Alterations along grain boundaries extended much further than the reaction zones, which indicates that fluid infiltration dominated over diffusion in the experiments. The experiments demonstrated that the H2O-CO2 fluid with dissolved major components released from the glaucophane schist can produce mineral assemblages of different chemical compositions in mantle materials: Na-bearing in websterite and K-bearing in harzburgite. The complementary components, K2O and CO2 for the websterite layer and Na2O for the harzburgite layer, are fixed in the initial glaucophane schist layer. The distinguished separation of alkalis and CO2 at the crust-mantle boundary can affect the character of metasomatism in the mantle wedge, primary magma compositions, and the chemical evolution of the rocks of the subducting slab.
DS201904-0766
2018
Yapaskurt, V.O.Pekov, I.V., Zubkova, N.V., Yapaskurt, V.O., Lykova, I.S., Chukanov, N.V., Belakovskiy, D.I., Britvin, S.N., Turchkova, A.G., Pushcharovsky, D.Y.Alexhomyakovite, K6(Ca2Na) (CO3)5CI.6h2O, a new mineral from the Khibiny alkaline complex, Kola Peninsula, Russia.European Journal of Mineralogy, Vol. 31, pp. 13-143.Russia, Kola Peninsuladeposit - Khibiny

Abstract: The new mineral alexkhomyakovite K6(Ca2Na)(CO3)5Cl?6H2O (IMA2015-013) occurs in a peralkaline pegmatite at Mt. Koashva, Khibiny alkaline complex, Kola peninsula, Russia. It is a hydrothermal mineral associated with villiaumite, natrite, potassic feldspar, pectolite, sodalite, biotite, lamprophyllite, titanite, fluorapatite, wadeite, burbankite, rasvumite, djerfisherite, molybdenite and an incompletely characterized Na-Ca silicate. Alexkhomyakovite occurs as equant grains up to 0.2 mm, veinlets up to 3 cm long and up to 1 mm thick and fine-grained aggregates replacing delhayelite. Alexkhomyakovite is transparent to translucent, colourless, white or grey, with vitreous to greasy lustre. It is brittle, the Mohs hardness is ca. 3. No cleavage was observed, the fracture is uneven. D meas = 2.25(1), D calc = 2.196 g cm?3. Alexkhomyakovite is optically uniaxial (-), ? = 1.543(2), ? = 1.476(2). The infrared spectrum is reported. The chemical composition [wt%, electron microprobe data, CO2 and H2O contents calculated for 5 (CO3) and 6 (H2O) per formula unit (pfu), respectively] is: Na2O 4.09, K2O 35.72, CaO 14.92, MnO 0.01, FeO 0.02, SO3 0.11, Cl 4.32, CO2 28.28, H2O 13.90, -O=Cl -0.98, total 100.39. The empirical formula calculated on the basis of 9 metal cations pfu is K5.90Ca2.07Na1.03(CO3)5(SO4)0.01O0.05Cl0.95?6H2O. The numbers of CO3 groups and H2O molecules are based on structure data. Alexkhomyakovite is hexagonal, P63/mcm, a = 9.2691(2), c = 15.8419(4) Å, V = 1178.72(5) Å3 and Z = 2. The strongest reflections of the powder X-ray diffraction pattern [d Å(I)(hkl)] are: 7.96(27)(002), 3.486(35)(113), 3.011(100)(114), 2.977(32)(211), 2.676(36)(300), 2.626(42)(213, 115), 2.206(26)(311) and 1.982(17)(008). The crystal structure (solved from single-crystal X-ray diffraction data, R = 0.0578) is unique. It is based on (001) heteropolyhedral layers of pentagonal bipyramids (Ca,Na)O5(H2O)2 interconnected via carbonate groups of two types, edge-sharing ones and vertex-sharing ones. Ca and Na are disordered. Ten-fold coordinated K cations centre KO6Cl(H2O)3 polyhedra on either side of the heteropolyhedral layer. A third type of carbonate group and Cl occupy the interlayer. The mineral is named in honour of the outstanding Russian mineralogist Alexander Petrovich Khomyakov (1933-2012).
DS202106-0964
2021
Yapaskurt, V.O.Perchuk, A.L., Sapegina, A.V., Safonov, O.G., Yapaskurt, V.O., Shatsky, V.S., Malkovets, V.G.Reduced amphibolite facies conditions in the Precambrian continental crust of the Siberian craton recorded by mafic granulite xenoliths from the Udachnaya kimberlite pipe, Yakutia.Precambrian Research, Vol. 357, 1061022, 14p. PdfRussia, Yakutiadeposit - Udachnaya

Abstract: It is widely accepted that granulite xenoliths from kimberlites provide a record of granulite facies metamorphism at the basement of cratons worldwide. However, application of the phase equilibria modeling for seven representative samples of mafic granulites from xenoliths of the Udachnaya kimberlite pipe, Yakutia, revealed that a granulitic garnet + clinopyroxene + plagioclase ± orthopyroxene ± amphibole ± scapolite mineral assemblage was likely formed in the middle crust under amphibolite facies conditions (600-650 °C and 0.8-1.0 GPa) in a deficiency of fluid. Clinopyroxene in the rocks is characterized by elevated aegirine content (up to 10 mol.%) both in the earlier magmatic cores and in the later metamorphic rim zones of the grains. Nevertheless, the phase equilibrium modeling for all samples indicates surprisingly reduced conditions, i.e. oxygen fugacity 1.6-3.3 log units below the FMQ (Fayalite-Magnetite-Quartz) buffer. In contrast, the coexistence of Fe-Ti oxides indicates temperatures of 850-990 °C and oxygen fugacity about lg(FMQ) ± 0.5, conditions which correspond to earlier stages of rock evolution. Reduction of oxygen fugacity during cooling is discussed in the context of the evolution of a complex fluid. The reconstructed P-T conditions for the final equilibration in the mafic granulites indicate that temperatures were ~250 °C higher than those extrapolated from the continental conductive geotherm of 35-40 µW/m2 deduced from peridotite xenoliths of the Udachnaya pipe. Although the granulites resided in the crust for a period for at least 1.4 Ga, they did not re-equilibrate to the temperatures of the geotherm, likely due to the blocking of mineral reactions under relatively low temperatures and fluid-deficient conditions
DS1992-0398
1992
Yarborogh, W.A.Dubray, J.J., Pantano, C.G., Yarborogh, W.A.Graphite as a substrate for diamond growthJournal of Applied Physics, Vol. 72, No. 7, October 1, pp. 3136-3142. # JT007GlobalDiamond genesis, Graphite
DS1989-1013
1989
Yarbrough, W.Messier, R., Yarbrough, W.SDI is diamond researchs best friendPhysics Today, Vol. 42, No. 9, September p. 146GlobalNews item, SDI
DS1990-1608
1990
Yarbrough, W.A.Yarbrough, W.A., Messier, R.Current issues and problems in the chemical vapor deposition of diamondScience, Vol. 247, pp. 688-696GlobalDiamond synthesis, Review
DS1998-1612
1998
Yardimicilar, C.Yardimicilar, C., Reeves, C.V.Evidence from aeromagnetic anomalies for the pre-drift fit of Madagascar against East Africa.Journal of African Earth Sciences, Vol. 27, 1A, p. 215. AbstractMadagascarGeophysics - aeromagnetics, Tectonics - Gondwana
DS1991-1905
1991
Yardley, B.Yardley, B., Bottrell, S.H., Cliff, R.A.Evidence for regional scale fluid loss event during mid crustalmetamorphismNature, Vol. 349, Jan. 10, pp. 151-4.Mantlemetamorphism
DS1996-0679
1996
Yardley, B.Jamtveit, B., Yardley, B.Fluid flow and transport in rocks: mechanisms and effectsChapman and Hall, ITP Distributors, approx. 150.00GlobalBook -ad, Sedimentary basins, fluid flow
DS1998-1430
1998
Yardley, B.Svensen, H., Jamtveit, B., Yardley, B., Austrheim, H.Eclogite facies fluids from the Caledonides of western Norway: compositions and implications for fluid-rock...Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 1481-2.NorwayEclogites, Fluid geochemistry
DS201909-2028
2019
Yardley, B.Cangelosi, D., Broom-Fendley, S., Banks, D., Morgan, D., Yardley, B.LREE redistribution during hydrothermal alteration at the Okorusu carbonatite complex, Namibia.Mineralogical Magazine, in press available 54p. PdfAfrica, Namibiacarbonatite - Okorusu

Abstract: The Cretaceous Okorusu carbonatite, Namibia, includes diopside-bearing and pegmatitic calcite carbonatites, both exhibiting hydrothermally altered mineral assemblages. In unaltered carbonatite, REE, Sr and Ba are largely hosted by calcite and fluorapatite. However, in hydrothermally altered carbonatites, small (< 50 ?m) parisite-(Ce) grains are the dominant REE host, while Ba and Sr are hosted in baryte, celestine, strontianite and witherite. Hydrothermal calcite has a much lower trace element content than the original, magmatic calcite. Despite the low REE contents of the hydrothermal calcite, the REE patterns are similar to those of parisite-(Ce), and magmatic minerals and mafic rocks associated with the carbonatites. These similarities suggest that hydrothermal alteration remobilised REE from magmatic minerals, predominantly calcite, without significant fractionation or addition from an external source. Ba and Sr released during alteration were mainly reprecipitated as sulfates. The breakdown of magmatic pyrite into Fe-hydroxide is inferred to be the main source of sulfate. The behaviour of sulfur suggests that the hydrothermal fluid was somewhat oxidising and it may have been part of a geothermal circulation system. Late hydrothermal massive fluorite replaced the calcite carbonatites at Okorusu and resulted in extensive chemical change, suggesting continued magmatic contributions to the fluid system.
DS1991-1906
1991
Yardley, B.W.D.Yardley, B.W.D.Quick shifts in plate motionNature, Vol. 254, No. 6351, November 28, pp. 269-270GlobalGeochronology, Tectonics
DS1994-1961
1994
Yardley, B.W.D.Yardley, B.W.D., Valley, J.W.How wet is the earth's crust?Nature, Vol. 371, Sept. 15, pp. 205-206MantleFluids, Basins
DS1995-2099
1995
Yardley, B.W.D.Yardley, B.W.D., Lloyd, G.E.Why metasomatic fronts are really metasomatic sidesGeology, Vol. 23, No. 1, Jan. pp. 53-56GlobalMetasomatism, Calc-silicate reaction zones
DS1998-1613
1998
Yardley, B.W.D.Yardley, B.W.D., Gleeson, S.A.Dry deep stable crust and its rheology: evidence from deep penetratingfluid.Geological Society of America (GSA) Annual Meeting, abstract. only, p.A393.NorwayRheology, Tectonics
DS200912-0837
2009
Yardley, B.W.D.Yardley, B.W.D.The role of water in the evolution of the continental crust.Journal of the Geological Society, Vol. 166, 4, pp. 585-600.MantleRheology
DS201412-1004
2014
Yardley, B.W.D.Yardley, B.W.D., Bodnar, R.J.Fluids in the continental crustGeochemical Perspectives Letters, Vol. 3, 1, pp. 1-127.MantleChemistry
DS1988-0395
1988
Yarger, H.Lam, C., Yarger, H.The structure of the central North American rift system in Kansas as interpreted from gravity dataGeological Society of America Abstracts with Program, Vol. 20, No. 2, January p. 121. Sth. Central, LawrenceKansasMid continent
DS1975-0421
1976
Yarger, H.L.Steeples, D.W., Yarger, H.L., Robinson, R.Integrated Geophysical Exploration for Kimberlites in KansasEos, Vol. 57, No. 10, P. 762, (ABTR.).GlobalKimberlite, Central States, Geophysics
DS1975-0689
1978
Yarger, H.L.Berendsen, P., Wilson, F.W., Yarger, H.L., et al.New Dat a on Major Basement Fractures in the Tectonic Development of Eastern Kansas.Proceedings of The Third International Conference On Basemen, No. 3, PP. 227-240.KansasKimberlite, Central States, Tectonics
DS1975-0898
1978
Yarger, H.L.Yarger, H.L., Robertson, R.R., Wentland, R.L.The Midcontinent Geophysical AnomalyKansas Academy of Science Transactions, Vol. 81, P. 184. (abstract.).GlobalMid-continent
DS1981-0435
1981
Yarger, H.L.Yarger, H.L.Aeromagnetic Survey of KansasEos, Vol. 62, No. 17, PP. 173-178.KansasGeophysics, Mid-continent
DS1983-0639
1983
Yarger, H.L.Yarger, H.L.Regional Interpretation of Kansas Aeromagnetic DataKansas Geological Survey Geophysical Series, No. 1, 35P.United States, KansasMid Continent
DS1983-0640
1983
Yarger, H.L.Yarger, H.L., Lam, C.K.New Gravity Dat a in Eastern KansasGeological Society of America (GSA), Vol. 15, No. 6, P. 724. (abstract.)KansasMid Continent
DS1984-0413
1984
Yarger, H.L.Knapp, R.W., Yarger, H.L.Integrated Geophysical Study of the Midcontinent Geophysical Anomaly Along the Kansas Cocorp Profile.Geological Society of America (GSA), Vol. 16, No. 2, FEBRUARY P. 88. (abstract.).KansasMid-continent
DS1984-0784
1984
Yarger, H.L.Yarger, H.L.Gravity and Magnetic Lineaments in KansasGeological Society of America (GSA), Vol. 16, No. 2, FEBRUARY P. 118. (abstract.).KansasMid-continent
DS1985-0378
1985
Yarger, H.L.Lam, CHI-KIN, Yarger, H.L.Preliminary Investigation of New Kansas Gravity MapGeological Society of America (GSA), Vol. 17, No. 5, MARCH P. 297. (abstract.).United States, Central States, KansasGravity, Geophysics
DS1986-0479
1986
Yarger, H.L.Lam, C.K., Yarger, H.L.Kansas basement age terrane boundary from gravity and magnetic dataGeological Society of America (GSA) Abstact Volume, Vol. 18, No. 6, p. 664. (abstract.)GlobalGeochronology, Geophysics
DS1989-1431
1989
Yarger, H.L.Somanas, C., Knapp, R.W., Yarger, H.L., Steeples, D.W.Geophysical model of the Midcontinent geophysical anomaly in northeasternKansasKansas Geological Survey, Bulletin. 226, pp. 215-228KansasGeophysics, Midcontinent
DS1990-0997
1990
Yarger, H.L.McCafferty, A.E., Adkins-Heljeson, D.M., Yarger, H.L.Complete bouguer gravity anomaly map of the Joplin Quadrangle Kansas andMissouriUnited States Geological Survey (USGS) Open File No. 89-0283, 1 sheet 1: 250, 000 $3.25, GlobalGeophysics-gravity
DS2000-0708
2000
Yarmoluk, Pkovski et al.Nikiforov, A.V., Yarmoluk, Pkovski et al.Late Mesozoic carbonatites of western Transbaikalia: mineralogical, chemical and isotopic characteristics ..Petrology, Vol. 8, No. 3, pp. 278-RussiaAlkaline magmatism, Carbonatite
DS200712-0578
2007
Yarmoluk, V.V.Kovalenko, V.I., Naumov, V.B., Girnis, A.V., Dorofeeva, V.A., Yarmoluk, V.V.Average contents of incompatible and volatile components in depleted, oceanic plume, and within plate continental mantle types.Doklady Earth Sciences, Vol. 445, 6, pp. DOI:10.1134/S1028334 X07060116MantleGeochemistry - plumes
DS201212-0359
2012
Yarmoluk, V.V.Kiselev, A.I., Ernst, R.E., Yarmoluk, V.V., Egorov, K.N.Radiating rifts and dyke swrms of the middle Paleozoic Yakutsk plume of eastern Siberian craton.Journal of Asian Earth Sciences, Vol. 45, 2, pp. 1-16.Russia, YakutiaDeposit - Mirmyi, Nakyn, Dladyn-Alakit
DS200912-0411
2009
Yarmolyk, V.V.Kovalenko, V.I., Yarmolyk, V.V., Bogatikov, O.A.Regularities of spatial distribution of mantle hot spots of the modern Earth.Doklady Earth Sciences, Vol. 427, 2, pp. 924-928.MantlePlume
DS200612-0740
2006
YarmolyukKovalenko, V.I., Yarmolyuk, Salnikova, Kozlovski, Kotov, Kovach, Vladykin, Savatenkov, V.M., Ponomarchuk, V.A.Geology and age of Khan-Bogdinsky massif of alkaline granitoids in southern Mongolia.Vladykin: VI International Workshop, held Mirny, Deep seated magmatism, its sources and plumes, pp. 17-45.Asia, MongoliaAlkaline rocks, granites
DS201112-1101
2011
Yarmolyuk, V.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
DS1991-0925
1991
Yarmolyuk, V.V.Kovalenko, V.I., Ionov, D.A., Yarmolyuk, V.V., Jagoutz, E.Isotope dat a on the evolution of the mantle and its correlation with the evolution of the crust in some parts of central AsiaGeochemistry International, Vol. 28, No. 4, pp. 82-92China, RussiaMantle, Geochronology
DS1992-1613
1992
Yarmolyuk, V.V.Vorontsov, A.A., Yarmolyuk, V.V.Devonian magmatic asssociations containing alkaline rocks from northwesternMongolia.Russian Geology and Geophysics, Vol. 33, No. 8, pp. 54-60.Russia, MongoliaAlkaline rocks
DS1995-1013
1995
Yarmolyuk, V.V.Kovalenko, V.I., Yarmolyuk, V.V.Endogenous rare metal ore formations and rare metal metallogeny ofMongolia.Economic Geology, Vol. 90, No. 3, May pp. 520-529.GlobalCarbonatite
DS1997-1278
1997
Yarmolyuk, V.V.Yarmolyuk, V.V., Kovalenko, V.I., Ivanov et al.Late Mesozoic volcanic carbonatites from the Transbaikal RegionDoklady Academy of Sciences, Vol. 355A, No. 6, July-Aug. pp. 845-49.RussiaCarbonatite
DS2000-1039
2000
Yarmolyuk, V.V.Yarmolyuk, V.V., Kovalenko, V.I.Geochemical and isotopic characteristics of the anomalous mantle of northern Asia in the Late PaleozoicDoklady Academy of Sciences, Vol. 375A, No. 9, pp. 1427-31.AsiaIntraplate mafic magmatism, Geochronology
DS2001-1281
2001
Yarmolyuk, V.V.Yarmolyuk, V.V., Kovalenko, V.I.Late Riphean break up between Siberia and Laurentia: evidence from intraplate magmatism.Doklady Academy of Sciences, Vol. 379, No. 5, June-July pp. 525-8.Russia, SiberiaMagmatism, Gondwana
DS2001-1282
2001
Yarmolyuk, V.V.Yarmolyuk, V.V., Nikiforov, A.V., Kovalenko, IvanovSources of Late Mesozoic carbonatites of western Transbaikalia: trace element and Sr neodymium isotopic data.Geochem, International, Vol. 39, No. S1 S99-109.RussiaGeochronology
DS2002-0895
2002
Yarmolyuk, V.V.Kovalenko, V.I., Naumov, V.B., Yarmolyuk, V.V., Dorofeeva, V.A., MigdisovBalance of H2O and Cl between the Earth's mantle and outer shellsGeochemistry International, Vol. 40, 10, Oct. pp. 943-71.MantleWater, chlorine
DS2002-1138
2002
Yarmolyuk, V.V.Nikiforov, A.V., Yarmolyuk, V.V., Kovalenko, IvanovLate Mesozoic carbonatites of western Transbaikalia: isotopic geochemicak characteristics and sources.Petrology, Vol.10,2,pp.146-64.RussiaCarbonatite
DS2002-1139
2002
Yarmolyuk, V.V.Nikiforov, A.V., Yarmolyuk, V.V., Kovalenko, IvanovLate Mesozoic carbonatites of western Transbaikalia: isotopic geochemical characteristics and sources.Petrology, Vol. 10, 2, pp. 146-64.Russia, TransbaikalCarbonatite
DS2003-1526
2003
Yarmolyuk, V.V.Yarmolyuk, V.V., Ivanov, V.G., Kovalenko, V.I., Pokrovskii, B.G.Magmatism and geodynamics of the southern Baikal volcanic region ( mantle hot spot):Petrology, Vol. 11, No. 1, pp. 1-30.RussiaGeochronology, Geochemistry
DS200512-0575
2002
Yarmolyuk, V.V.Kovalenko, V.I., Yarmolyuk, V.V., Vladykin, N.V., Kozlovsky, A.M.Processes leading to eclogitization (densification) of subducted and tectonically buried crust.Deep Seated Magmatism, magmatism sources and the problem of plumes., pp. 23-41.Asia, RussiaMagmatism
DS200512-0594
2001
Yarmolyuk, V.V.Kuzmin, M.I., Yarmolyuk, V.V., Kovalenko, V.I., Ivanov, V.G.Evolution of central Asian 'hot' field in the Phanerozoic and some problems of plume tectonics.Alkaline Magmatism and the problems of mantle sources, pp. 242-256.Asia, RussiaTectonics
DS200512-1216
2004
Yarmolyuk, V.V.Yarmolyuk, V.V., Kovalenko, V.I., Naumov, V.B.Volatile component flows in the upper shells of the Earth caused by deep-seated geodynamic processes.Deep seated magmatism, its sources and their relation to plume processes., pp. 5-28.MantleGeodynamics
DS200512-1217
2005
Yarmolyuk, V.V.Yarmolyuk, V.V., Kovalenko, V.I., Naumov, V.B.Geodynamics, flows of volatile components and their exchange between the mantle and the Earth's upper shells.Geotectonics, Vol.39, 1,pp. 39-55.MantleTectonics
DS200612-0739
2006
Yarmolyuk, V.V.Kovalenko, V.I., Naumov, V.B., Girnis, A.V., Dorofeeva, V.A., Yarmolyuk, V.V.Composition and chemical structure of oceanic mantle plumes.Petrology, Vol. 14, 5, pp. 452-476.MantleGeochemistry - hot spots
DS200612-1490
2005
Yarmolyuk, V.V.Vorontsov, A.V., Yarmolyuk, V.V., Kovalenko, V.I., Lykhin, D.A., Drill, S.I., Tatarnikov, S.A.Composition, sources and conditions of magmatism in the north Mongolia, Trans Baikal early Mesozoic rift zone.Problems of Sources of deep magmatism and plumes., pp. 59-01.Asia, MongoliaMagmatism
DS200612-1566
2005
Yarmolyuk, V.V.Yarmolyuk, V.V., Kovalenko, V.I., Salnikova, E.B., Nijiforov, A.V., Lotov, A.B., Vladykin, N.V.Late Riphean rifting and breakup of Laurasia: dat a on geochronological studies of ultramafic alkaline complexes in the southern framing of the Siberian Craton.Doklady Earth Sciences, Vol. 404, 7, pp. 1031-1036.RussiaTectonics, geochronology
DS200912-0383
2009
Yarmolyuk, V.V.Kislelev, A.I., Yarmolyuk, V.V., Egorov, K.N.Potassium basalts and picrobasalts from the Devonian kimberlite fields of western Yakutia, Russia: and their relation to kimberlite magmatism.Geology of Ore Deposits, Vol. 51, 1, pp. 33-50.Russia, YakutiaDeposit - Vilyui-Markha
DS200912-0412
2009
Yarmolyuk, V.V.Kovalenko, V.I., Yarmolyuk, V.V., Bogatikov, O.A.The recent supercontinent in the northern hemisphere of the Earth ( North Pangea): magmatic and geodynamic evolution.Doklady Earth Sciences, Vol. 427, 2, pp. 897-901.MantleMagmatism
DS201012-0409
2009
Yarmolyuk, V.V.Kovalenko, V.I., Naumov, V.B., Girnis, A.V., Dorofeeva, V.A., Yarmolyuk, V.V.Average compositions of magmas and mantle sources of Mid-Ocean Ridges and intraplate Oceanic and Continental settings estimated from the dat a of melt inclusionsDeep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., p.35-78,MantleGlasses of basalts
DS201012-0410
2009
Yarmolyuk, V.V.Kovalenko, V.I., Yarmolyuk, V.V., Bogatikov, O.A.The recent supercontinent in the northern hemisphere of the Earth ( North Pangea): magmatic and geodynamic evolution.Deep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., p. 151-157.MantleMagmatism
DS201012-0411
2009
Yarmolyuk, V.V.Kovalenko, V.I., Yarmolyuk, V.V., Bogatikov, O.A.Regularities of spatial distribution of mantle hot spots of the modern Earth.Deep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., pp. 5-12.MantlePlume
DS201012-0419
2010
Yarmolyuk, V.V.Kuzmin, M.I., Yarmolyuk, V.V., Kravchinsky, V.A.Phanerozoic hot spot traces and paleogeographic reconstructions of the Siberian continent based on interaction with the Africa large low shear velocity province.Earth Science Reviews, Vol. 102, 2, pp. 29-59.AfricaPaleowandering
DS201112-0299
2011
Yarmolyuk, V.V.Egorov, K.N., Kiselev, A.I., Yarmolyuk, V.V., Nikiforov, A.V.Composition and sources of magmatism of the middle Paleozoic Vilyui rift area and the problem of combination of its basic and kimberlitic derivatives.Doklady Earth Sciences, Vol. 436, 1, pp. 76-82.RussiaMagmatism
DS201112-0548
2011
Yarmolyuk, V.V.Kovalenko, V.I., Kozlovsky, A.M., Yarmolyuk, V.V.Comendite bearing subduction related volcanic associations in the Khan-Bogd area, southern Mongolia: geochemical data.Deep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., pp. 5-38.Asia, MongoliaSubduction - basites
DS201112-0549
2010
Yarmolyuk, V.V.Kovalenko, V.I., Naumov, V.B., Girnis, A.V., Dorofeeva, V.A., Yarmolyuk, V.V.Average composition of basic magmas and mantle sources of island arcs and active continental margins estimated from the dat a on melt inclusions and quenched glassesVladykin, N.V., Deep Seated Magmatism: its sources and plumes, pp. 22-53.MantlePetrology
DS201112-0550
2010
Yarmolyuk, V.V.Kovalenko, V.I., Yarmolyuk, V.V., Bogatikov, O.A.Modern volcanism in the Earth's northern hemisphere and its relation with the evolution of the North Pangaea modern supercontinent and with the spatial ... hotspotsPetrology, Vol. 18, 7, pp. 657-676.MantleMantle plume, deep subduction
DS201112-0563
2011
Yarmolyuk, V.V.Kuzmin, M.I., Yarmolyuk, V.V., Kravchiniski, V.A.Absolute paleogeographic reconstructions of the Siberian Craton in the Phanerozoic: a problem of time estimation of superplumes.Doklady Earth Sciences, Vol. 437, 1, pp. 311-315.Russia, SiberiaMagmatism - age, hot spots, African comparison
DS201112-0726
2011
Yarmolyuk, V.V.Naumov, V.B., Kovanenko, V.I., Dorofeeva, V.A., Girnis, A.V., Yarmolyuk,V.V.Average compositions of igneous melts from main geodynamic settings according to the investigation of melt inclusions in minerals& quenched glasses of rocks.Deep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., pp. 171-204.MantleMelt inclusion database
DS201412-0952
2014
Yarmolyuk, V.V.Vladykin, N.V., Kotov, A.B., Borisenko, A.S., Yarmolyuk, V.V., Pokhilenko, N.P., Salnikova, E.B., Travin, A.V., Yakovleva, S.Z.Age boundaries of formation of the Tomtor alkaline ultramafic pluton: U Pb and 40 Ar 39 Ar geochronological studies.Doklady Earth Sciences, Vol. 454, 1, pp. 7-11.RussiaGeochronology
DS201412-0953
2014
Yarmolyuk, V.V.Vladykin, N.V., Sotnikov, I.A., Kotov, A.B., Yarmolyuk, V.V., Salnikova, E.B., Yakovleva, S.Z.Structure, age and ore potential of the Burpala rare-metal alkaline Massif, northern Baikal region.Geology of Ore Deposits, Vol. 56, 4, pp. 239-256.RussiaAlkalic
DS201412-1005
2014
Yarmolyuk, V.V.Yarmolyuk, V.V., Kuzmin, M.I., Kozlovsky, A.M.Late Paleozoic early Mesozoic within-plate magmatism in North Asia: traps, rifts, giant batholiths, and the geodynamics of their origin.Deep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., pp. 66-103.AsiaMagmatism
DS201903-0529
2018
Yarmolyuk, V.V.Lykhin, D.A., Yarmolyuk, V.V., Nikiforov, A.V., Kozlovsky, A.M., Magazina, L.O.Ulan-Tologoi Ta - Nb deposit: the role of magmatism in the formation of rare metal mineralization.Geology of Ore Deposits, Vol. 60, 6, pp. 461-85.Asia, MongoliaREE

Abstract: The role of magmatic differentiation is considered for the formation of the Ulan-Tologoi Ta-Nb-Zr deposit (northwestern Mongolia) related to the eponymous alkali granite pluton. Data are presented on the structure of the pluton, the composition of its rocks, and distribution of rare metal mineralization. The ores of the pluton include alkali granites with contents of ore elements exceeding the normative threshold for Ta (>100 ppm). The rare metal mineralization includes pyrochlore, columbite, zircon, bastnaesite, monazite, and thorite, which are typical of all alkali-salic rocks; however, their amount varies depending on the REE content of the rocks. The pluton was formed ~298 Ma ago under the influence of a mantle-crustal melt source.
DS201903-0535
2019
Yarmolyuk, V.V.Nikiforov, A.V., Yarmolyuk, V.V.Late Mesozoic carbonatite provinces in Central Asia: their compositions, sources and genetic settings.Gondwana Research, Vol. 69, pp. 56-72.Asia, China, Russia, Siberiacarbonatite

Abstract: Identification of the Late Mesozoic carbonatite province in Central Asia is herein discussed. Its regional extent and distribution is investigated, and the areas with manifestations of carbonatite magmatism are described. It is shown that they were developed in terranes with heterogeneous and heterochronous basements: Siberian (Aldan Shield) and North China cratons; Early Paleozoic (Caledonian) and Middle-Late Paleozoic (Hercynian) structures of the Central Asian fold belt (Transbaikal and Tuva zones in Russia; Mongolia). Irrespective of the structural position, the carbonatites were generated within a relatively narrow time interval (150-118?Ma). The geochemical (Sr, LREE, Ba, F and P) specialization of carbonatites of the province is reflected in their mineral composition. Some rocks of the carbonatite complexes always include one or more distinctive minerals: fluorite, Ba-Sr sulfates, Ba-Sr-Ca carbonates, LREE fluorocarbonates, or apatite. Compared to counterparts from other age groups (for example, Maimecha-Kotui group in North Asia), these carbonatites are depleted in Ti, Nb, Ta, Zr and Hf. It is shown that the Sr and Nd isotope composition of carbonatites correlates with the geological age of the host crust. Rocks of carbonatite complexes associated with cratons are characterized by the lowest ?Nd(T) and highest ISr(T) values, indicating that their formation involved an ancient lithospheric material. Carbonatite magmatism occurred simultaneously with the largest plateau basalts 130-120?Ma ago in rift zones in the Late Mesozoic intraplate volcanic province of Central Asia. This interval corresponds to timing of global activation of intraplate magmatism processes, suggesting a link of the carbonatite province with these processes. It is shown that fields with the carbonatite magmatism were controlled by small mantle plumes (“hot fingers”) responsible for the Central Asian mantle plume events.
DS1995-2100
1995
Yaroshevskiy, A.A.Yaroshevskiy, A.A.The mean composition of crustal magmatic materialGeochemistry International, Vol. 32, No. 12, Dec. 1, pp. 104-112GlobalGeochemistry, Magma
DS1997-1279
1997
Yaroshevsky, A.A.Yaroshevsky, A.A.Average chemical composition of the main groups of magmatic associations In the Earth Crust.Geochemistry International, Vol. 35, No. 8, pp. 689-694.GlobalMagma, Chemical composition, geochemistry
DS200612-1567
2006
Yaroshevsky, A.A.Yaroshevsky, A.A.Abundances of chemical elements in the Earth's crust.Geochemistry International, Vol. 44, 1, pp. 48-55.MantleGeochemistry
DS1990-1609
1990
Yaroslavskiy, R.I.Yaroslavskiy, R.I.The most general prerequisites of diamond bearing potential of some Igneous rocks of central Asia.(Russian)Dokl. Akad. Sci. SSSR, (Russian), No. 1, pp. 40-42RussiaDiamond potential, Igneous rocks
DS1990-1610
1990
Yarovoy, P.N.Yarovoy, P.N., Konov, A.A., Serykh, S.V.Nature of the luminesence of certain minerals from the Murun alkalicmassifDoklady Academy of Science USSR, Earth Science Section, Vol. 304 No. 1-6, pp. 226-228RussiaAlkaline, Murun massif
DS1985-0356
1985
Yashina, R.M.Kononova, V.A., Yashina, R.M.Geochemical criteria for differentiating between rare metallic carbonatites and barren carbonatite like rocksIndian Mineralogist, Sukheswala Volume, pp. 136-150IndiaCarbonatite
DS1985-0357
1985
Yashina, R.M.Kononova, V.A., Yashina, R.M.Geochemical criteria for differentiation between rare metallic carbonatites and barren carbonatite like rocksIndian Minerals, Special Volume, Sukhneswala, pp. 136-150IndiaCarbonatite, Geochemistry
DS1988-0771
1988
Yaskevich, V.G.Yegorov, I.V., Sorokin, M.Yu., Yaskevich, V.G.The experience of structural geomorphological studies in predicting kimberlite spatial distribution.(Russian)Geomorfologiya, (Russian), Vol. 1988, No. 3, pp. 24-28RussiaPetrology, Geomorphology
DS200712-1117
2007
YasnevVernikovskaya, I.V., Salnikova, Matushkin, YasnevThe Neoproterozoic alkaline rocks of the Yenisey Ridge, western margin of the Siberian Craton: mineralogy, geochemistry and geochronology.Plates, Plumes, and Paradigms, 1p. abstract p. A1065.RussiaIjolite
DS200712-0834
2007
YasnyginaPerepelov, A.B., Puzankov, M.Yu., Ivanov, Filosfova, Demonetova, Smirnova, Chuvshaova, YasnyginaNeogene basanites in western Kamchatka: mineralogy, geochemistry and geodynamic setting.Petrology, Vol. 15, 5, Sept. pp. 488-508.Russia, KamchatkaBasanites, Foidites
DS200712-0876
2007
YasnyginaRasskazov, S.V., Ilyasova, A.M., Konev, A.A., Yasnygina, Maslovskaya, Feflov, Demonterova, SaraninaGeochemical evidence of the Zadoi alkaline ultramafic Massif, Cis Sayan area southern Siberia.Geochemistry International, Vol. 45, 1, pp. 1-14.Russia, SiberiaAlkalic
DS201012-0550
2010
Yasnygina, et al.Oktaybrskii, N.V., Vladykin, A.M., Lennikov, A.A., Vrzhosek, T.A., Yasnygina, et al.Chemical composition and geochemical characteristics of the Koksharovka alkaline ultrabasic massif with carbonatites.Geochimica et Cosmochimica Acta, Vol.74, 19, pp. 778-791.Asia, RussiaCarbonatite
DS200812-0510
2008
Yasnygina, T.Ivanov, A., Demonterova, E., Rasskazov, S., Yasnygina, T.Low Ti melts from southeastern Siberian traps large igneous province: evidence for a water rich mantle source?Journal of Earth System Science, Vol. 117, 1, pp. 1-21.Russia, SiberiaWater
DS201612-2288
2016
Yasnygina, T.Chuvashova, I., Rasskazov, S., Yasnygina, T.Mid-Miocene thermal impact on the lithosphere by sub-lithospheric convective mantle material: transition from high- to moderate MG magmatism beneath Vitim Plateau, Siberia.Geoscience Frontiers, in press availableRussia, SiberiaConvection

Abstract: High-Mg lavas are characteristic of the mid-Miocene volcanism in Inner Asia. In the Vitim Plateau, small volume high-Mg volcanics erupted at 16-14 Ma, and were followed with voluminous moderate-Mg lavas at 14-13 Ma. In the former unit, we have recorded a sequence of (1) initial basaltic melts, contaminated by crustal material, (2) uncontaminated high-Mg basanites and basalts of transitional (K-Na-K) compositions, and (3) picrobasalts and basalts of K series; in the latter unit a sequence of (1) initial basalts and basaltic andesites of transitional (Na-K-Na) compositions and (2) basalts and trachybasalts of K-Na series. From pressure estimation, we infer that the high-Mg melts were derived from the sub-lithospheric mantle as deep as 150 km, unlike the moderate-Mg melts that were produced at the shallow mantle. The 14-13 Ma rock sequence shows that initial melts equilibrated in a garnet-free mantle source with subsequently reduced degree of melting garnet-bearing material. No melting of relatively depleted lithospheric material, evidenced by mantle xenoliths, was involved in melting, however. We suggest that the studied transition from high- to moderate-Mg magmatism was due to the mid-Miocene thermal impact on the lithosphere by hot sub-lithospheric mantle material from the Transbaikalian low-velocity (melting) domain that had a potential temperature as high as 1510 °?. This thermal impact triggered rifting in the lithosphere of the Baikal Rift Zone.
DS200812-0511
2008
Yasnygina, T.A.Ivanov, A.V., Demonterova, E.I., Rasskazov, S.V., Yasnygina, T.A.Low Ti melts from the southeastern Siberian Traps large Igneous Province: evidence for a water rich mantle source?Journal of Earth System Science, Vol. 117, 1, pp. 1-21.Russia, SiberiaMelting
DS201012-0737
2010
Yasnygina, T.A.Soloveva, L.V., Yasnygina, T.A., Korolyuk, V.N., Egorov, K.N.Geochemical evolution of deep fluids in the mantle lithosphere of the Siberian Craton during the Middle Paleozoic kimberlite cycle.Doklady Earth Sciences, Vol. 434, 2, pp.1330-1336.RussiaGeochemistry - melting
DS201012-0738
2010
Yasnygina, T.A.Soloveva, L.V., Yasnygina, T.A., Kostrovitskii, S.I.Isotopic and geochemical evidence for a subduction setting during formation of the mantle lithosphere in the northeastern part of the Siberian Craton.Doklady Earth Sciences, Vol. 432, 2, pp. 799-803.RussiaSubduction
DS201212-0689
2012
Yasnygina, T.A.Soloveva, Kostrovitsky, S., Yasnygina, T.A.Fluid and magma transfer in subcontinental lithospheric mantle of the Siberian craton and its geochemical evolution.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, SiberiaGeochemistry
DS201312-0867
2012
Yasnygina, T.A.Soloveva, L.V., Yasnygina, T.A., Egorov, K.N.Metasomatic parageneses in deep seated xenoliths from pipes Udachnaya and Komosomolskaya Magnitinaya as indicators of fluid transfer through the manyle lithosphere of the Siberian Craton.Russian Geology and Geophysics, Vol. 53, 12, pp. 1291-1303.RussiaDeposit - Udachnaya, Komosomolskaya
DS1998-1614
1998
Yasuda, A.Yasuda, A., Fujii, T.Ascending subducted oceanic crust entwined with mantle plumesGeophysical Research Letters, Vol. 25, No. 10, May 15, p. 1561-MantlePlumes, Subduction
DS2002-1102
2002
Yasuda, A.Mube, K., Fujii, T., Yasuda, A.Composition of aqueous fluid coexisting with mantle minerals at high pressure and its bearing on the differentiation of the Earth's mantle.Geochimica et Cosmochimica Acta, Vol.66,12, June pp. 2273-86.MantleGeochemistry - melt
DS2003-0701
2003
Yasuda, A.Kenji, M., Takashi, O., Yasuda, A., Fujii, T.Connectivity of aqueous fluid in eclogite and its implications for fluid migration in theJournal of Geophysical Research, Vol. 108, B6, 10.1029/2002JB001960 June 6MantleEclogite, Water
DS200412-0973
2003
Yasuda, A.Kenji, M., Takashi, O., Yasuda, A., Fujii, T.Connectivity of aqueous fluid in eclogite and its implications for fluid migration in the Earth's interior.Journal of Geophysical Research, Vol. 108, B6, 10.1029/2002 JB001960 June 6MantleEclogite Water
DS200612-0913
2006
Yasuda, A.Mibe, K., Fujii, T., Yasuda, A., Ono, S.Mg Fe partitioning between olivine and ultramafic melts at high pressures.Geochimica et Cosmochimica Acta, Vol. 70, 3, Feb. 1, pp. 757-766.MantleMagmatism
DS1984-0712
1984
Yasuda, T.Sunagawa, I., Tsukamoto, K., Yasuda, T.Surface microtopographic and x ray topographic study of octahedral crystals of natural diamond from SiberiaMaterials Science of the Earth's Interior, Terra Sci. Publ, pp. 331=349RussiaCrystallography
DS1984-0713
1984
Yasuda, T.Sunagawa, I., Tsukamoto, K., Yasuda, T.Surface microtopographic and x-ray topographic study of octahedral crystals of natural diamond from SiberiaIn: Material Science of the Earth's Interior, D. Reidel Publ, pp. 331-349RussiaDiamond Morphology
DS1998-1423
1998
Yasuda, T.Sungagawa, I., Yasuda, T., Fukushima, H.Fingerprinting of two diamonds cut from the same roughGems and Gemology, Vol. 34, Winter, pp. 270-83.GlobalDiamond morphology, Topography, tomography, crystallography
DS200912-0695
2008
Yasuhara, A.Sinmyo, R., Ozawa, H., Jirose, K., Yasuhara, A., Endo, N., Sata, N., Ohishi, Y.Ferric iron content in (Mg,Fe) SiO3 perovskite and post-perocskite at deep lower mantle conditions.American Mineralogist, Vol. 93, 11/12 pp. 1899-1902.MantlePerovskite
DS201112-0969
2011
Yasuhara, A.Sinmyo, R., Hirose, K., Muto, S., Ohishi, Y., Yasuhara, A.The valence state and partitioning of iron in the Earth's lowermost mantle.Journal of Geophysical Research, Vol. 116, B7, B07205.MantleChemistry
DS200912-0456
2009
Yasunaga, K.Lu, T., Odaki, T., Yasunaga, K., Uesugi, H.A fancy reddish brown diamond with new optical absorption features.Journal of Gemmology, Vol. 31, 2-4, pp. 73-76.TechnologyDiamond colour
DS1989-1667
1989
Yatabe, S.M.Yatabe, S.M., Fabbri, A.G.Putting AI to work in geoscienceEpisodes, Vol. 12, No. 1, March pp. 10-17. Database # 17845GlobalComputer, Artificial Intelligence
DS1993-1791
1993
Yates, D.Yates, D., Matthews, D., Deakin, S.Hard rock diamond mining at Argyle Diamond Mines Pty. LtdAustralia Min. Met. Mawby Memorial Volume, Mon. 19, pp. 1443-1448.AustraliaMining, Deposit -Argyle
DS1993-1792
1993
Yates, D.Yates, D., Matthews, D., Deakin, S.Open pit mining at Argyle diamond mine, western AustraliaThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin) , Annual Meeting Abstracts LESS than approximately 10, Vol. 86, No. 968, March ABSTRACT p. 75.AustraliaMining, Mineral processing, Deposit -Argyle
DS2000-1040
2000
Yatsenko, G.M.Yatsenko, 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
DS1988-0392
1988
Yatsenko, V.G.Kvasnitsa, V.N., Krochuk, V.M., Melnikov, V.S., Yatsenko, V.G.Crystal morphology of graphite from magmatic rocks Of the Ukrainianshield.(Russian)Mineral Zhurn., (Russian), Vol. 10, No. 5, pp. 68-76RussiaCarbonatite
DS200412-0847
2004
Yatsevich, I.Honda, M., Phillips, D., Harris, J.W., Yatsevich, I.Unusual noble gas compositions in polycrystalline diamonds: preliminary results from the Jwaneng kimberlite, Botswana.Chemical Geology, Vol. 203, 3-4, Feb. 16, pp. 347-358.Africa, BotswanaMantle evolution, lithosphere, geochemistry
DS1995-2101
1995
Yatskevich, B.Yatskevich, B.Latest updates on Russian geological endowments and investment climate inRussiaWorld Mining Congress, Institute International Research held May, 5pRussiaEconomics -investment
DS1992-1718
1992
Yatsu, E.Yatsu, E.The nature of weathering: an introductionAmerican Journal of Science, Vol. 292, No. 3, March pp. 226-?GlobalWeathering, Overview -introduction
DS201902-0261
2019
Yatte, D.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.
DS2000-1041
2000
Yaukutake, T.Yaukutake, T.The inner core and the surface heat flow as clues to estimating the initial temperature of the Earth's core.Physical Earth and Planetary Interiors, Vol. 121, No.1-2, Sept. pp.103-37.MantleHeat flow
DS200512-0889
2005
Yaun, X.Ramesh, D.S., Kumar, M.R., Devi, E.U., Raju, P.S., Yaun, X.Moho geometry and upper mantle images of northeast India.Geophysical Research Letters, Vol. 32, 14, July 28, L14301IndiaGeophysics - seismics
DS2001-1283
2001
Yavez, F.Yavez, F.PYROX: a computer program for IMA pyroxene classification and calculation scheme.Computers and Geosciences, Vol. 27, No. 1, Feb. pp. 97-107.GlobalComputer - PYROX
DS200812-0022
2008
Yavouba, C.Allialy, M.E., Djro, S.C., Yavouba, C., Konamelan, A.N., Pothin, K.B., Yao, D.B., Yobou, R.Comparative geochemistry of Seguela kimberlites, South Africa Group II kimberlites and other worldwide kimberlites.9IKC.com, 3p. extended abstractAfrica, West Africa, Ivory CoastDeposit - Bobi, Toubabouko
DS1996-1577
1996
Yavuz, F.Yavuz, F.AMPHICAL: a quick basic program for determining the amphibole name from electron microprobe analysis..IMA.Computers and Geosciences, Vol. 22, No. 2, pp. 101-107GlobalComputer, Program - AMPHICAL
DS1997-1280
1997
Yavuz, F.Yavuz, F., Pztas, T.BIOTERM - a program for evaluting and plotting microprobe analyses of biotite from magmatic suitesComputers and Geosciences, Vol. 23, No. 8, pp. 897-907GlobalCopper porphyry, hydrothermal alteration, Computer - BIOTERM.
DS2001-1284
2001
Yavuz, F.Yavuz, F.PYROX: a computer program for the IMA pyroxene classification and calculation scheme.Computers and Geosciences, Vol. 27, No.1, pp. 97-107.GlobalComputer, Program - PYROX
DS2003-1527
2003
Yavuz, F.Yavuz, F.Evaluating micas in petrologic and metallogenic aspect: I definitions and structure of theComputers and Geosciences, Vol. 29, 10, pp. 1203-13.GlobalComputer - petrology
DS2003-1528
2003
Yavuz, F.Yavuz, F.Evaluating micas in petrologic and metallogenic aspect: II applications using theComputers and Geosciences, Vol. 29, 10, pp. 1215-28.GlobalComputer - petrology
DS200412-2177
2003
Yavuz, F.Yavuz, F.Evaluating micas in petrologic and metallogenic aspect: I definitions and structure of the computer program MICA+Computers & Geosciences, Vol. 29, 10, pp. 1203-13.TechnologyComputer - petrology
DS200412-2178
2003
Yavuz, F.Yavuz, F.Evaluating micas in petrologic and metallogenic aspect: II applications using the computer program MICA+Computers & Geosciences, Vol. 29, 10, pp. 1215-28.TechnologyComputer - petrology
DS1989-0251
1989
Yaw Kwarteng, A.Chavez, P.S. Jr., Yaw Kwarteng, A.Extracting spectral contrast in Land sat thematic mapper image dat a using selective principal componentanalysisPhotogrammetric Engineering and Remote Sensing, Vol. 55. No. 3, March, pp. 339-348.GlobalRemote Sensing, Landsat
DS1992-1719
1992
Yaxley, G.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
DS1997-0605
1997
Yaxley, G.Klemme, S., Yaxley, G., Foley, S.F., Horn, I.Trace element composition of carbonatite melts in the earth's uppermantle.Geological Association of Canada (GAC) Abstracts, POSTER.MantleCarbonatite
DS2000-0633
2000
Yaxley, G.Matsumoto, T., Honda, M., Yaxley, G.Noble gases in pyroxenites and metasomatised peridotites from Newer Volcanics, Mantle MetasomatismChemical Geology, Vol. 168, No. 1-2, July 1, pp. 49-74.Australia, SoutheastMetasomatism, Geochemistry
DS200612-0630
2006
Yaxley, G.Jacob, D., Resiberg, L., Yaxley, G.Processes of mantle refertilization and modification.Goldschmidt Conference 16th. Annual, S5-05 theme abstract 1/8p. goldschmidt2006.orgMantleCraton
DS200812-0426
2007
Yaxley, G.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
DS201312-0938
2013
Yaxley, G.Vasilyev, V., Yaxley, G., Hermann, J., O'Neill, H.Phase relations of carbonate eclogite during subduction and the effect of redox conditions on diamond - carbonate reactions.Goldschmidt 2013, 1p. AbstractTechnologyEclogite
DS201412-0944
2014
Yaxley, G.Vasilyev, P., Yaxley, G., Hermann, J., O'Neill, H., Berry, A.Experimental investigation of the effect of oxygen fugacity on diamond versus carbonate in carbon-bearing eclogites during deep subduction.Goldschmidt Conference 2014, 1p. AbstractMantleSubduction
DS201603-0431
2016
Yaxley, G.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
Yaxley, G.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?
DS201910-2310
2019
Yaxley, G.Yaxley, G., Foley, S.Mantle metasomatism, oxidation and kimberlite magma genesis.Goldschmidt2019, 1p. AbstractMantlediamond genesis

Abstract: High pressure experimental studies investigating the petrogenesis of kimberlites have focussed on the effects of CO2 and/or H2O on deep, partial melting of peridotite, or on locating the point of multiple saturation of peridotite phases on the liquidus of putative “primary” kimberlite melts in pressure-temperature space. These studies have failed to reach consensus regarding the source mineralogy or the pressure-temperature conditions of partial melting. An alternative hypothesis is that precursor melts to Group I kimberlites formed under conditions too reducing for carbonate stability, around the iron-wüstite (IW) buffer in the asthenospheric mantle below the cratonic lithosphere. The few experimental constraints on the nature of partial melts produced under these conditions suggest they are hydrous, highly olivine-normative and may contain a small dissolved carbonate component; they are not yet kimberlites at this early stage. Kimberlites have sampled large vertical sections of the cratonic lithospheric mantle in many locations, as garnet peridotite xenoliths. Studies of these xenoliths show that the cratonic mantle decreases in oxygen fugacity (ƒO2) with depth, reaching values ? IW near the base of the lithosphere at 6-7 GPa. However, many deep samples were metasomatically enriched and oxidised to ƒO2 values at which carbonate phases are stable [1,2]. Metasomatism in the deep cratonic mantle may also lead to enrichment in K2O, CaO, CO2 and H2O as modal metasomatic phases such as carbonates, phlogopite and clinopyroxene [3]. The asthenosphere-derived, reduced precursor melts to kimberlites may segregate from their source region and interact with this metasomatised lithosphere, dissolving these metasomatic components and evolving to high K/Na, CaO, CO2 and H2O-rich melts, which on modification during transport to the surface, may erupt as kimberlites.
DS1991-1907
1991
Yaxley, G.M.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
DS1994-1962
1994
Yaxley, G.M.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
Yaxley, G.M.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
DS1996-1578
1996
Yaxley, G.M.Yaxley, G.M.Origin of glass in mantle xenoliths from southeastern AustraliaGeological Society of Australia 13th. Convention held Feb., No. 41, abstracts p. 486.AustraliaXenoliths -glass
DS1997-1281
1997
Yaxley, G.M.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
Yaxley, G.M.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
Yaxley, G.M.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
Yaxley, G.M.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
DS1999-0818
1999
Yaxley, G.M.Yaxley, G.M.Phase relations of carbonated eclogite under Upper Mantle PT conditions - implications for carbonatite ..7th International Kimberlite Conference Nixon, Vol. 2, pp. 933-39.MantlePetrology - petrogenesis, experimental Ocean Island Basalt (OIB)., Carbonatite
DS1999-0819
1999
Yaxley, G.M.Yaxley, G.M., Kamenetsky, V.In situ origin for glass in mantle xenoliths from southeastern Australia:insights from trace elements...Earth and Planetary Science Letters, Vol. 172, No. 1-2, Oct. 15, pp. 97-110.AustraliaXenoliths - glass, Metasomatism
DS2000-0359
2000
Yaxley, G.M.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
Yaxley, G.M.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
DS2000-1042
2000
Yaxley, G.M.Yaxley, G.M.Experimental study of the phase and melting relations of homogeneous basalt and peridotite mixtures....Contributions to Mineralogy and Petrology, Vol. 139, No. 3, pp. 326-38.GlobalPetrogenesis - flood basalts
DS2001-0407
2001
Yaxley, G.M.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
DS200412-2141
2004
Yaxley, G.M.Woodland, A.B., Seitz, H.M., Yaxley, G.M.Varying behaviour of Li in metasomatised spinel peridotite xenoliths from western Victoria, Australia.Lithos, Vol. 75, 1-2, July pp. 55-66.AustraliaGeochemistry - trace element fingerprinting, petrogenet
DS200412-2179
2004
Yaxley, G.M.Yaxley, G.M., Brey, G.P.Phase relations of carbonate bearing eclogite assemblages from 2.5 to 5.5 GPa: implications for petrogenesis of carbonatites.Contributions to Mineralogy and Petrology, Vol. 146, 5, pp. 606-619.TechnologyCarbonatite, mineralogy
DS200512-1218
2004
Yaxley, G.M.Yaxley, G.M., Kamenetsky, V.S., Kamenetsky, M., Norman, M.D., Francis, D.Origins of compositional heterogeneity in olivine hosted melt inclusions from the Baffin Island picrites.Contributions to Mineralogy and Petrology, Vol. 148, 4, pp. 426-442.Canada, Nunavut, Baffin IslandPicrite
DS200612-0534
2006
Yaxley, G.M.Harlou, R., Pearson, D.G., Davidson, J.P., Kamenetsky, V.S., Yaxley, G.M.Source variability and crustal contamination of the Baffin Island picrites - coupled Sr isotope and trace element study of individual melt inclusions.Geochimica et Cosmochimica Acta, Vol. 70, 18, 1, p. 11, abstract only.Canada, Nunavut, Baffin IslandPicrite
DS200612-0592
2006
Yaxley, G.M.Hofer, H.E., Brey, G.P., Yaxley, G.M., Berry, A.J.Iron oxidation state determination in garnets by EPMA and XANES.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 256. abstract only.TechnologyGarnet geochemistry
DS200612-1568
2006
Yaxley, G.M.Yaxley, G.M.Carbonate eclogite in the upper mantle.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 6. abstract only.MantleEclogite geochemistry
DS200712-0910
2007
Yaxley, G.M.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
DS200712-1201
2007
Yaxley, G.M.Yaxley, G.M., O'Neill, H.St.C.A new experimental calibration of Ni Mg exchange between garnet and olivine at Upper mantle pressures - implications for Ni in garnet thermometry.Geological Association of Canada, Gac-Mac Yellowknife 2007, May 23-25, Volume 32, 1 pg. abstract p.88.MantleGeothermometry
DS200712-1202
2007
Yaxley, G.M.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
DS200812-0363
2008
Yaxley, G.M.Foley, S.F., Yaxley, G.M., Rosenthal, A., Rapp, R.P., Jacob, D.E.Experimental melting of peridotites in the presence of CO2 and H2O at 40 - 60 kbar.9IKC.com, 3p. extended abstractTechnologyPeridotite - melting
DS200812-0446
2008
Yaxley, G.M.Handler, M.R., Baker, J.A., Schiller, M., Bennett, V.C., Yaxley, G.M.Stable Mg isotope composition of Earth's mantle,Goldschmidt Conference 2008, Abstract p.A348.MantleGeochronology
DS200812-0572
2008
Yaxley, G.M.Kiseeva, E.S., Yaxley, G.M., Kamenetsky, V.S.The role of carbonated eclogite in kimberlite and carbonatite petrogenesis.9IKC.com, 3p. extended abstractMantleModels, eclogite
DS200812-0972
2008
Yaxley, G.M.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
DS200912-0382
2009
Yaxley, G.M.Kiseeva, E.S., Yaxley, G.M., Kamenetsky, V.S.Melting of carbonated eclogite at 3.5-5.5 GPa: an experimental study.Goldschmidt Conference 2009, p. A663 Abstract.MantleKimberlite genesis
DS200912-0838
2009
Yaxley, G.M.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
DS201012-0050
2010
Yaxley, G.M.Berry, A.J., Yaxley, G.M., Woodland, A.B., Foran, G.J.A XANES calibration for determining the oxidation state of iron in mantle garnet.Chemical Geology, Vol. 278, 1-2, Nov. pp. 31-37.TechnologyGarnet mineralogy
DS201012-0205
2009
Yaxley, G.M.Foley, S.F., Yaxley, G.M., Rosenthal, A., Buhre, S., Kisseeva, E.S., Rapp, R.P., Jacob, D.E.The composition of near solidus melts of peridotite in the presence of CO2 and H2O between 40 and 60 kbar.Lithos, Vol. 112 S pp. 274-283.MantleMineral chemistry
DS201012-0611
2010
Yaxley, G.M.Rapp, R.P., Norman, M.D., Laporte, D., Yaxley, G.M., Martin, H., Foley, S.F.Continent formation in the Archean and chemical evolution of the cratonic lithosphere: melt rock reaction experiments at 3-4 GPa and petrogenesisJournal of Petrology, Vol. 51, 6, pp. 1237-1266.MantleSanukitoids
DS201012-0638
2010
Yaxley, G.M.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
DS201112-0085
2011
Yaxley, G.M.Berry, A.J., Yaxley, G.M., Hanger, B.J., Woodland, A.B., De Jonge, M.D., Howard, D.L., Paterson, D.Quantitative mapping of the oxidation state of iron in mantle garnet.Goldschmidt Conference 2011, abstract p.522.TechnologyIndicator of diamond versus carbonate stability
DS201112-1135
2011
Yaxley, G.M.Yaxley, G.M., Berry, A.J., Kamenetsky, V.S., Woodland, A.B., Paterson, D., De Jong, M.D., Howard, D.L.Redox profile through the Siberian craton: Fe K edge XANES determination of Fe3/Fe2 in garnet from peridotite xenoliths in the Udachnaya kimberlite.Goldschmidt Conference 2011, abstract p.2217.RussiaThermobarometry
DS201212-0356
2012
Yaxley, G.M.Kiseeva, E.S., Litasov, K.D., Yaxley, G.M., Ohtani, E.Carbonated eclogite at 3.5-5.5 Gpa - the effect of the capsule material on solidus temperatures.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractTechnologyDiamond/carbon crystallography
DS201212-0357
2012
Yaxley, G.M.Kiseeva, E.S., Litasov, K.D., Yaxley, G.M., Ohtani, E., Kamenetsky, V.S.Phase relations of eclogite + 4% CO2 at 9-21 GPA: implications for diamond formation in the deep mantle.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractMantleDiamond genesis
DS201212-0358
2012
Yaxley, G.M.Kiseeva, E.S., Yaxley, G.M., Hermann, J., Litasov, K.D., Rosenthal, A., Kamenetsky, V.S.An experimental study of carbonated eclogite at 3 - 5-5 GPA - implications for silicate and carbonate metasomatism in the cratonic mantle.Journal of Petrology, Vol. 53, pp. 727-759.MantleMetasomatism
DS201212-0598
2012
Yaxley, G.M.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
Yaxley, G.M.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
DS201212-0802
2012
Yaxley, G.M.Yaxley, G.M., Berry, A.J., Kamenetsky, V.S., Woodland, A.B., Golovin, A.V.An oxygen fugacity profile through the Siberian craton - Fe K-edge XANES determinations of Fe3 Fe in garnets in peridotite xenoliths from the Udachnaya East kimberlite.Lithos, in press availableRussia, SiberiaDeposit - Udachnaya
DS201212-0803
2012
Yaxley, G.M.Yaxley, G.M., Berry, A.J., Kamenetsky, V.S., Woodland, A.B., Paterson, D., DeJonge, M.D., Howard, D.Application of Fe K-edge xanes determinations of Fe3+/OFE in garnet to peridotite xenoliths from the Udachnaya kimberlite.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, YakutiaDeposit - Udachnaya
DS201212-0804
2012
Yaxley, G.M.Yaxley, G.M., Berry, A.J., Kamenetsky, V.S., Woodland, A.B., Paterson, D., DeJonge, M.D., Howard, D.Application of Fe K-edge xanes determinations of Fe3+/OFE in garnet to peridotite xenoliths from the Udachnaya kimberlite.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, YakutiaDeposit - Udachnaya
DS201312-0077
2013
Yaxley, G.M.Berry, A.J., Yaxley, G.M., Hanger, B.J., Woodland, A.B., De Jonge, M.D., Howard, D.L., Paterson, D., Kamenetsky, V.S.Quantitative mapping of the oxidative effects of mantle metasomatism.Geology, Vol. 41, pp. 683-686.Africa, South AfricaDeposit - Wesselton
DS201312-0359
2013
Yaxley, G.M.Hanger, B.J., Yaxley, G.M., Berry, A.J., Kemenetsky, V.S., Paterson, D., Howard, D.L.Fe XANES measurements of Fe3 in garnet from the Kimberley pipe.Goldschmidt 2013, AbstractAfrica, South AfricaDeposit - Kimberley
DS201312-0486
2013
Yaxley, G.M.Kiseeva, E.S., Litasov, K.D., Yaxley, G.M., Ohtani, E., Kamenetsky, V.S.Melting and phase relations of carbonated eclogite at 9-21 GPa and the petrogenesis of alkali rich melts in the deep mantle.Journal of Petrology, Vol. 54, 8, pp. 1555-1583.MantleEclogite
DS201312-0487
2013
Yaxley, G.M.Kiseeva, E.S., Yaxley, G.M., Stepanov, A.S., Tkalcic, H., Litasov, K.D., Kamenetsky, V.S.Metapyroxenite in the mantle transition zone revealed from majorite inclusions in diamonds.Geology, Vol. 41, 8, pp. 883-886.MantleClassification - comparison majorites
DS201312-0543
2013
Yaxley, G.M.Litasov, K.D., Shatskiy, A., Ohtani, E., Yaxley, G.M.Solidus of alkaline carbonatite in the deep mantle.Geology, Vol. 41, pp. 79-82.MantleCarbonatite
DS201312-0993
2013
Yaxley, G.M.Yaxley, G.M., Berry, A.J., Woodland, A.B., Hanger, B.J., Kamenetsky, V.S.Xenoliths, XANES and redox related processes in the cratonic lithosphere.Goldschmidt 2013, 1p. AbstractMantleRedox
DS201412-0312
2014
Yaxley, G.M.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
DS201412-0338
2014
Yaxley, G.M.Hanger, B.J., Yaxley, G.M., Berry, A.J., Kamenetsky, V.S.Relationships between oxygen fugacity and metasomatism in the Kaapvaal subcratonic mantle, represented by garnet peridotite xenoliths in the Wesselton kimberlite, South Africa.Lithos, Vol. 212-215 pp. 443-452.Africa, South AfricaDeposit - Wesselton
DS201412-0617
2014
Yaxley, G.M.Nebel, O., Rapp, R.P., Yaxley, G.M.The role of detrital zircons in Hadean crustal research.Lithos, Vol. 190-191, pp. 313-327.MantleGeochronology
DS201412-1006
2013
Yaxley, G.M.Yaxley, G.M., Kamenetsky, V.S., Nichols, G.T., Maas, R., Belousova, E., Rosenthal, A., Norman, M.The discovery of kimberlites in Antarctica extends the vast Gondwanan Cretaceous province.Nature Communications, Dec. 17, 7p.AntarcticaPrince Charles Mountains
DS201506-0279
2015
Yaxley, G.M.Kamenetsky, V.S., Yaxley, G.M.Carbonate-silicate iquid immiscibility in the mantle propels kimberlite magma ascent.Geochimica et Cosmochimica Acta, Vol. 158, pp. 48-56.MantleCarbonatite, content of kimberlite melts
DS201510-1776
2015
Yaxley, G.M.Kamenetsky, V.S.,Park, J-W., Mungall, J.E., Pushkarev, E.V., Ivanov, A.V., Kamenetsky, M.B., Yaxley, G.M.Crystallization of platinum group minerals from silicate melts: evidence from Cr-spinel hosted inclusions in volcanic rocks.Geology, Vol. 43, 10, pp. 903-906.RussiaMeimechite

Abstract: The formation of platinum-group minerals (PGM) during magma differentiation has been suggested to be an important process in primitive magma evolution, but decisive textural evidence is difficult to obtain because PGM tend to be very small and very rare. We have investigated Cr-spinel phenocrysts from two oxidized magmas (Siberian meimechite and Vanuatu [Ambae Island] arc picrite) and one reduced magma (Uralian [Russia] ankaramite) for PGM inclusions and their platinum-group element (PGE) contents. We observed Os-Ir and Pt-Fe alloys entrapped as inclusions in Cr-spinel in all three suites of lava. The alloys may occur in association with PGE-bearing sulfides and co-trapped silicate melt. Cr-spinel crystals also contain measurable amounts of Os, Ir, Ru, and Rh, which are at concentrations 2×–100× higher than mantle values. Thermodynamic models indicate that the arc picrite and ankaramite melts were probably both saturated with the observed PGM phases, whereas the Os-Ir alloy grain observed in the meimechite is not in equilibrium with the “bulk” melt. Our results demonstrate that PGM (alloys and sulfides) occur as liquidus phases in primitive (unfractionated) melts at high temperature and at a variety of redox conditions, and that Cr-spinel is a significant host of PGE, either in the crystal structure or as PGM inclusions.
DS201610-1877
2016
Yaxley, G.M.Kamenetsky, V.S., Maas, R., Kamenetsky, M.B., Yaxley, G.M., Ehrig, K., Zellmer, G.F., Bindeman, I.N., Sobolev, A.V., Kuzmin, D.V., Ivanov, A.V., Woodhead, J., Schilling, J-G.Multiple mantle sources of continental magmatism: insights from "high-Ti" picrites of Karoo and other large igneous provinces.Chemical Geology, in press available 10p.Africa, South AfricaLIP magmatism

Abstract: Magmas forming large igneous provinces (LIP) on continents are generated by extensive melting in the deep crust and underlying mantle and associated with break-up of ancient supercontinents, followed by formation of a new basaltic crust in the mid-oceanic rifts. A lack of the unifying model in understanding the sources of LIP magmatism is justified by lithological and geochemical complexity of erupted magmas on local (e.g. a cross-section) and regional (a single and different LIP) scales. Moreover, the majority of LIP rocks do not fit general criteria for recognizing primary/primitive melts (i.e. < 8 wt% MgO and absence of high-Fo olivine phenocrysts). This study presents the mineralogical (olivine, Cr-spinel, orthopyroxene), geochemical (trace elements and Sr-Nd-Hf-Pb isotopes) and olivine-hosted melt inclusion compositional characteristics of a single primitive (16 wt% MgO), high-Ti (2.5 wt% TiO2) picrite with high-Mg olivine (up to 91 mol% Fo) from the Letaba Formation in the ~ 180 Ma Karoo LIP (south Africa). The olivine compositions (unusually high ?18O (6.17‰), high NiO (0.36-0.56 wt%) and low MnO and CaO (0.12-0.20 and 0.12-0.22 wt%, respectively)) are used to argue for a non-peridotitic mantle source. This is supported by the enrichment of the rock and melts in most incompatible trace elements and depletion in heavy rare earth elements (e.g. high Gd/Yb) that reflects residual garnet in the source of melting. The radiogenic isotopes resemble those of the model enriched mantle (EM-1) and further argue for a long-term enrichment of the source in incompatible trace elements. The enriched high-Ti compositions, strongly fractionated incompatible trace elements, presence of primitive olivine and high-Cr spinel in the Letaba picrites are closely matched by olivine-phyric rocks from the ~ 260 Ma Emeishan (Yongsheng area, SW China) and ~ 250 Ma Siberian (Maimecha-Kotuy region, N Siberia) LIPs. However, many other compositional parameters (e.g. trace element and ?18O compositions of olivine phenocrysts, Fe2 +/Fe3 + in Cr-spinel, Sr-Nd-Hf isotope ratios) only partially overlap or even diverge. We thus imply that parental melts of enriched picritic rocks with forsteritic olivine from three major continental igneous provinces - Karoo, Emeishan and Siberia cannot be assigned to a common mantle source and similar melting conditions. The Karoo picrites also exhibit some mineralogical and geochemical similarities with rocks and glasses in the south Atlantic Ridge and adjacent fracture zones. The geodynamic reconstructions of the continental plate motions since break-up of the Gondwanaland in the Jurassic support the current position of the source of the Karoo magmatism in the southernmost Atlantic. Co-occurrence of modern and recent anomalous rocks with normal mid-ocean ridge basalts in this region can be related to blocks/rafts of the ancient lithosphere, stranded in the ambient upper mantle and occasionally sampled by rifting-related decompressional melting.
DS201707-1328
2017
Yaxley, G.M.Giuliani, A.M., Tappe, S., Rooney, T.O., McCoy-West, A.J., Yaxley, G.M., Mezger, K.Editorial: the role of intraplate magmas and their inclusions in Earth's mantle evolution.Chemical Geology, Vol. 455, pp. 1-5.Mantlemagmatism

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 cores, 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.
DS201707-1337
2017
Yaxley, G.M.Kamenetsky, V.S., Maas, R., Kamenetsky, M.B., Yaxley, G.M., Ehrig, K., Zellmer, G.F., Bindeman, I.N., Sobolev, A.V., Kuzmin, D.V., Ivanov, A.V., Woodhead, J., Schilling, J-G.Multiple mantle sources of continental magmatism: insights from high Ti picrites of Karoo and other large igneous provinces.Chemical Geology, Vol. 455, pp. 22-31.Africa, South Africamagmatism

Abstract: Magmas forming large igneous provinces (LIP) on continents are generated by extensive melting in the deep crust and underlying mantle and associated with break-up of ancient supercontinents, followed by formation of a new basaltic crust in the mid-oceanic rifts. A lack of the unifying model in understanding the sources of LIP magmatism is justified by lithological and geochemical complexity of erupted magmas on local (e.g. a cross-section) and regional (a single and different LIP) scales. Moreover, the majority of LIP rocks do not fit general criteria for recognizing primary/primitive melts (i.e. < 8 wt% MgO and absence of high-Fo olivine phenocrysts). This study presents the mineralogical (olivine, Cr-spinel, orthopyroxene), geochemical (trace elements and Sr-Nd-Hf-Pb isotopes) and olivine-hosted melt inclusion compositional characteristics of a single primitive (16 wt% MgO), high-Ti (2.5 wt% TiO2) picrite with high-Mg olivine (up to 91 mol% Fo) from the Letaba Formation in the ~ 180 Ma Karoo LIP (south Africa). The olivine compositions (unusually high ?18O (6.17‰), high NiO (0.36–0.56 wt%) and low MnO and CaO (0.12–0.20 and 0.12–0.22 wt%, respectively)) are used to argue for a non-peridotitic mantle source. This is supported by the enrichment of the rock and melts in most incompatible trace elements and depletion in heavy rare earth elements (e.g. high Gd/Yb) that reflects residual garnet in the source of melting. The radiogenic isotopes resemble those of the model enriched mantle (EM-1) and further argue for a long-term enrichment of the source in incompatible trace elements. The enriched high-Ti compositions, strongly fractionated incompatible trace elements, presence of primitive olivine and high-Cr spinel in the Letaba picrites are closely matched by olivine-phyric rocks from the ~ 260 Ma Emeishan (Yongsheng area, SW China) and ~ 250 Ma Siberian (Maimecha-Kotuy region, N Siberia) LIPs. However, many other compositional parameters (e.g. trace element and ?18O compositions of olivine phenocrysts, Fe2 +/Fe3 + in Cr-spinel, Sr-Nd-Hf isotope ratios) only partially overlap or even diverge. We thus imply that parental melts of enriched picritic rocks with forsteritic olivine from three major continental igneous provinces – Karoo, Emeishan and Siberia cannot be assigned to a common mantle source and similar melting conditions. The Karoo picrites also exhibit some mineralogical and geochemical similarities with rocks and glasses in the south Atlantic Ridge and adjacent fracture zones. The geodynamic reconstructions of the continental plate motions since break-up of the Gondwanaland in the Jurassic support the current position of the source of the Karoo magmatism in the southernmost Atlantic. Co-occurrence of modern and recent anomalous rocks with normal mid-ocean ridge basalts in this region can be related to blocks/rafts of the ancient lithosphere, stranded in the ambient upper mantle and occasionally sampled by rifting-related decompressional melting.
DS201707-1338
2017
Yaxley, G.M.Kiseeva, E.S., Kamenetsky, V.S., Yaxley, G.M., Shee, S.R.Mantle melting versus mantle metasomatism - the chicken or the egg dilemma.Chemical Geology, Vol. 455, pp. 120-130.Mantlemetasomatism

Abstract: Most eclogitic mantle xenoliths brought to the surface exhibit a certain degree of enrichment with incompatible elements, usually attributed to the effect of mantle metasomatism by a putative metasomatic fluid. The metasomatic overprint is represented mainly by enrichments in Na, K, Ba, Ti and LREE and the original source of this fluid remains unknown. In this paper, we present a detailed petrological study of a typical eclogitic mantle xenolith from the Roberts Victor kimberlite mine in South Africa. We find that its textural and mineralogical features present strong evidence for incipient melting. The melting assemblage we observe did not necessarily require introduction of additional components, that is: in-situ melting alone could produce highly incompatible element enriched melt without involvement of a hypothetical and speculative “metasomatic event”. Due to the higher abundance in incompatible elements and lower solidus temperature than peridotites, mantle eclogites, some of which represent previously subducted oceanic crust, are much more plausible sources of mantle metasomatism, but on the other hand, they can be considered as highly metasomatised themselves. This brings us to the “chicken or egg” dilemma – was the secondary mineral assemblage in mantle lithologies a result or a source of mantle metasomatism?
DS201709-1991
2017
Yaxley, G.M.Goodarzi, P.Y., Berry, A.J., Pearson, D.G., Yaxley, G.M., Newville, M.Garnet as a recorder of metasomatism in the sub-continental lithospheric mantle. Goldschmidt Conference, abstract 1p.Africa, Namibiadeposit , Louwerensia

Abstract: Metasomatism by fluid or melt is commonly attributed as the cause of chemical and modal heterogeneity observed in peridotite xenoliths from the sub-continental lithospheric mantle. Documented manifestations are (1) perturbation of the oxygen fugacity (fO2), which may affect the stability of carbon-bearing phases, and (2) trace-element enrichment, typified by the shape of REEN patterns. Garnet, which contains Fe2+ and Fe3+ in measurable quantities, and exhibits prominent variation in REEN patterns between samples, may record the metasomatic history of the mantle. Here we report variations of fO2 and trace element concentrations for a suite of 22 garnet-bearing peridotite xenoliths from the Louwrensia kimberlite, south-central Namibia. The xenoliths span an estimated pressure range between 2.7 and 4.5 GPa. Fe3+/?Fe of garnet was determined by Fe K-edge XANES spectroscopy. Concomitant fO2 was calculated using the oxybarometer calibration of Miller et al. [1]. The trace element concentrations of all phases were determined by LA-ICP-MS. A global dataset comprising 454 garnet REEN patterns from 19 kimberlites has been compiled. The REEN pattern of each sample was fit to orthogonal polynomial functions that parameterise the abundance, slope, quadratic curvature, and cubic curvature [2]. Quadratic and cubic curvature correlate with abundance, albeit with considerable scatter. There is, however, an absence of correlation between REEN patterns and fO2, depth, or modal abundance. This is in contrast to correlations and trends observed for basaltic melts that clearly identify petrogenetic trends. The partitioning of REEs between garnet and co-existing phases in these samples highlights pronounced trace-element disequilibrium and hence question the validity of considering garnet REEN in isolation as a means of discerning metasomatic history
DS201712-2696
2018
Yaxley, G.M.Jollands, M.C., Hanger, B.J., Yaxley, G.M., Hermann, J., Kilburn, M.R.Timescales between mantle metasomatism and kimberlite ascent indicated by diffusion profiles in garnet crystals from periodotite xenoliths.Earth and Planetary Science Letters, Vol. 481, pp. 143-153.Africa, South Africadeposit - Wesselton

Abstract: Rare garnet crystals from a peridotite xenolith from the Wesselton kimberlite, South Africa, have distinct zones related to two separate episodes of mantle metasomatism. The garnet cores were firstly depleted through melt extraction, then equilibrated during metasomatism by a potentially diamond-forming carbonate-bearing or proto-kimberlitic fluid at 1100-1300?°C and 4.5-5.5 GPa. The garnet rim chemistry, in contrast, is consistent with later overgrowth in equilibrium with a kimberlite at around and . This suggests that the rock was physically moved upwards by up to tens of kilometres between the two metasomatic episodes. Preserved high Ca, Al and Cr contents in orthopyroxenes suggest this uplift was tectonic, rather than magmatic. Diffusion profiles were measured over the transitions between garnet cores and rims using electron microprobe (Mg, Ca, Fe for modelling, plus Cr, Mn, Ti, Na, Al) and nano Secondary Ion Mass Spectrometry (NanoSIMS; 89Y, along with 23Na, Ca, Cr, Fe, Mn and Ti) analyses. The short profile lengths (generally <10 ?m) and low Y concentrations (0.2-60 ppm) make the NanoSIMS approach preferable. Diffusion profiles at the interface between the zones yield constraints on the timescale between the second metasomatic event and eruption of the kimberlite magma that brought the xenolith to the surface. The time taken to form the diffusion profiles is on the order of 25 days to 400 yr, primarily based on modelling of Y diffusion along with Ca, Fe and Mg (multicomponent diffusion) profiles. These timescales are too long to be produced by the interaction of the mantle xenolith with the host kimberlite magma during a single-stage ascent to the crust (hours to days). The samples offer a rare opportunity to study metasomatic processes associated with failed eruption attempts in the cratonic lithosphere.
DS201805-0946
2018
Yaxley, G.M.Golovin, A.V., Sharygin, I.S., Kamenetsky, V.S., Korsakov, A.V., Yaxley, G.M.Alkali-carbonate melts from the base of cratonic lithospheric mantle: links to kimberlites.Chemical Geology, Vol. 483, pp. 261-274.Russiadeposit - Udachnaya

Abstract: Identification of the primary compositions of mantle-derived melts is crucial for understanding mantle compositions and physical conditions of mantle melting. However, these melts rarely reach the Earth's surface unmodified because of contamination, crystal fractionation and degassing, processes that occur almost ubiquitously after melt generation. Here we report snapshots of the melts preserved in sheared peridotite xenoliths from the Udachnaya-East kimberlite pipe, in the central part of the Siberian craton. These xenoliths are among the deepest mantle samples and were delivered by kimberlite magma from 180-230?km depth interval, i.e. from the base of the cratonic lithosphere. The olivine grains of the sheared peridotites contain secondary inclusions of the crystallized melt with bulk molar (Na?+?K)/Ca?~?3.4. Various Na-K-Ca-, Na-Ca-, Na-Mg-, Ca-Mg- and Ca-carbonates, Na-Mg-carbonates with additional anions, alkali sulphates and halides are predominant among the daughter minerals in secondary melt inclusions, whereas silicates, oxides, sulphides and phosphates are subordinate. These inclusions can be considered as Cl-S-bearing alkali-carbonate melts. The presence of aragonite, a high-pressure polymorph of CaCO3, among the daughter minerals suggests a mantle origin for these melt inclusions. The secondary melt inclusions in olivine from the sheared peridotite xenoliths and the melt inclusions in phenocrystic olivines from the host kimberlites demonstrate similarities, in daughter minerals assemblages and trace-element compositions. Moreover, alkali-rich minerals (carbonates, halides, sulphates and sulphides) identified in the studied melt inclusions are also present in the groundmass of the host kimberlites. These data suggests a genetic link between melt enclosed in olivine from the sheared peridotites and melt parental to the Udachnaya-East kimberlites. We suggest that the melt inclusions in olivine from mantle xenoliths may represent near primary, kimberlite melts. These results are new evidence in support of the alkali?carbonate composition of kimberlite melts in their source regions, prior to the kimberlite emplacement into the crust, and are in stark contrast to the generally accepted ultramafic silicate nature of parental kimberlite liquids.
DS201808-1755
2018
Yaxley, G.M.Jollands, M.C., Hanger, B.J., Yaxley, G.M., Hermann, J., Kilburn, M.R.Timescales between mantle metasomatism and kimberlite ascent indicated by diffusion profiles in garnet crystals from peridotite xenoliths.Earth and Planetary Science Letters, Vol. 481, 1, pp. 143-153.Mantlekimberlite

Abstract: Rare garnet crystals from a peridotite xenolith from the Wesselton kimberlite, South Africa, have distinct zones related to two separate episodes of mantle metasomatism. The garnet cores were firstly depleted through melt extraction, then equilibrated during metasomatism by a potentially diamond-forming carbonate-bearing or proto-kimberlitic fluid at 1100-1300?°C and 4.5-5.5 GPa. The garnet rim chemistry, in contrast, is consistent with later overgrowth in equilibrium with a kimberlite at around and . This suggests that the rock was physically moved upwards by up to tens of kilometres between the two metasomatic episodes. Preserved high Ca, Al and Cr contents in orthopyroxenes suggest this uplift was tectonic, rather than magmatic. Diffusion profiles were measured over the transitions between garnet cores and rims using electron microprobe (Mg, Ca, Fe for modelling, plus Cr, Mn, Ti, Na, Al) and nano Secondary Ion Mass Spectrometry (NanoSIMS; 89Y, along with 23Na, Ca, Cr, Fe, Mn and Ti) analyses. The short profile lengths (generally <10 ?m) and low Y concentrations (0.2-60 ppm) make the NanoSIMS approach preferable. Diffusion profiles at the interface between the zones yield constraints on the timescale between the second metasomatic event and eruption of the kimberlite magma that brought the xenolith to the surface. The time taken to form the diffusion profiles is on the order of 25 days to 400 yr, primarily based on modelling of Y diffusion along with Ca, Fe and Mg (multicomponent diffusion) profiles. These timescales are too long to be produced by the interaction of the mantle xenolith with the host kimberlite magma during a single-stage ascent to the crust (hours to days). The samples offer a rare opportunity to study metasomatic processes associated with failed eruption attempts in the cratonic lithosphere.
DS201810-2374
2018
Yaxley, G.M.Rosenthal, A., Yaxley, G.M., Crichton, W.A., Kovacs, I.J., Spandler, C., Hermann, J., Sandorne, J.K., Rose-Koga, E., Pelleter, A-A.Phase relations and melting of nominally 'dry' residual eclogites with variable CaO/Na2O from 3 to 5 Gpa and 1250 to 1500C; implications for refertilisation of upwelling heterogeneous mantle. Lithos, Vol. 314-315, pp. 506-519.Mantlemelting
DS201812-2822
2018
Yaxley, G.M.Jaques, A.L., Luguet, A., Smith, C.B., Pearson, D.G., Yaxley, G.M., Kobussen, A.F.Argyle deposit: Nature of the mantle beneath the Argyle AK1 lamproite pipe: constraints from mantle xenoliths, diamonds, and lamproite geochemistry.Society of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, pp. 119-144.Australia, western Australiadeposit - Argyle
DS201905-1034
2019
Yaxley, G.M.Golovin, A.V., Sharygin, I.S., Kamenetsky, V.S., Korsakov, A.V., Yaxley, G.M.Alkali-carbonate melts from the base of cratonic lithospheric mantle: links to kimberlites.Chemical Geology, Vol. 483, pp. 261-274.Russia, Yakutiadeposit - Udachnaya -East

Abstract: Identification of the primary compositions of mantle-derived melts is crucial for understanding mantle compositions and physical conditions of mantle melting. However, these melts rarely reach the Earth's surface unmodified because of contamination, crystal fractionation and degassing, processes that occur almost ubiquitously after melt generation. Here we report snapshots of the melts preserved in sheared peridotite xenoliths from the Udachnaya-East kimberlite pipe, in the central part of the Siberian craton. These xenoliths are among the deepest mantle samples and were delivered by kimberlite magma from 180-230?km depth interval, i.e. from the base of the cratonic lithosphere. The olivine grains of the sheared peridotites contain secondary inclusions of the crystallized melt with bulk molar (Na?+?K)/Ca?~?3.4. Various Na-K-Ca-, Na-Ca-, Na-Mg-, Ca-Mg- and Ca-carbonates, Na-Mg-carbonates with additional anions, alkali sulphates and halides are predominant among the daughter minerals in secondary melt inclusions, whereas silicates, oxides, sulphides and phosphates are subordinate. These inclusions can be considered as Cl-S-bearing alkali-carbonate melts. The presence of aragonite, a high-pressure polymorph of CaCO3, among the daughter minerals suggests a mantle origin for these melt inclusions. The secondary melt inclusions in olivine from the sheared peridotite xenoliths and the melt inclusions in phenocrystic olivines from the host kimberlites demonstrate similarities, in daughter minerals assemblages and trace-element compositions. Moreover, alkali-rich minerals (carbonates, halides, sulphates and sulphides) identified in the studied melt inclusions are also present in the groundmass of the host kimberlites. These data suggests a genetic link between melt enclosed in olivine from the sheared peridotites and melt parental to the Udachnaya-East kimberlites. We suggest that the melt inclusions in olivine from mantle xenoliths may represent near primary, kimberlite melts. These results are new evidence in support of the alkali?carbonate composition of kimberlite melts in their source regions, prior to the kimberlite emplacement into the crust, and are in stark contrast to the generally accepted ultramafic silicate nature of parental kimberlite liquids.
DS201912-2780
2019
Yaxley, G.M.Foley, S.F., Yaxley, G.M., Kjarsgaard, B.A.Kimberlites: from source to surface, insights from experiments.Elements, Vol. 15, 6, pp.Mantlepetrology
DS202001-0050
2020
Yaxley, G.M.Yaxley, G.M., Ghosh, S., Kiseeva, E.S., Mallick, A., Spandler, C., Thomson, A.R., Walter, M.J.Co2 rich melts in the earth.IN: Deep Carbon: past to present. Editors Orcutt, Danielle, Dasgupta, pp. 129-162.Mantlemelting

Abstract: This chapter reviews the systematics of partial melting of mantle lithologies - like peridotite and eclogite - in the presence of carbon dioxide. It discusses the composition of mantle-derived magmas generated in the presence of carbon dioxide and whether magmas erupted on Earth’s surface resemble carbonated magmas from the mantle. It reviews how the production of carbon dioxide-rich magma in the mantle varies as a function of tectonic settings - beneath continents and oceans and in subduction zones - and time.
DS202103-0414
2021
Yaxley, G.M.Sudholz, Z.J., Yaxley, G.M., Jaques, A.L., Brey, G.P.Experimental recalibration of the Cr-in-clinpyroxene geobarometer: improved precision and reliability above 4.5 Gpa.Contributions to Mineralogy and Petrology, Vol. 176, 10.1007/s0041 0-020-01768-z 21p. PdfMantlegeothermometry

Abstract: The pressure dependence of the exchange of Cr between clinopyroxene and garnet in peridotite is applicable as a geobarometer for mantle-derived Cr-diopside xenocrysts and xenoliths. The most widely used calibration (Nimis and Taylor Contrib Miner Petrol 139: 541-554, 2000; herein NT00) performs well at pressures below 4.5 GPa, but has been shown to consistently underestimate pressures above 4.5 GPa. We have experimentally re-examined this exchange reaction over an extended pressure, temperature, and compositional range using multi-anvil, belt, and piston cylinder apparatuses. Twenty-nine experiments were completed between 3-7 GPa, and 1100-1400 °C in a variety of compositionally complex lherzolitic systems. These experiments are used in conjunction with several published experimental datasets to present a modified calibration of the widely-used NT00 Cr-in-clinopyroxene (Cr-in-cpx) single crystal geobarometer. Our updated calibration calculates P (GPa) as a function of T (K), CaCr Tschermak activity in clinopyroxene (acpxCaCrTs), and Cr/(Cr?+?Al) (Cr#) in clinopyroxene. Rearranging experimental results into a 2n polynomial using multiple linear regression found the following expression for pressure: P(GPa)=11.03+(?T(K) ln(acpxCaCrTs)×0.001088)+(1.526×ln(Cr#cpxT(K))) where Cr#cpx=(CrCr+Al), acpxCaCrTs=Cr?0.81?Cr#cpx?(Na+K), with all mineral components calculated assuming six oxygen anions per formula unit in clinopyroxene. Temperature (K) may be calculated through a variety of geothermometers, however, we recommend the NT00 single crystal, enstatite-in-clinopyroxene (en-in-cpx) geothermometer. The pressure uncertainty of our updated calibration has been propagated by incorporating all analytical and experimental uncertainties. We have found that pressure estimates below 4 GPa, between 4-6 GPa and above 6 GPa have associated uncertainties of 0.31, 0.35, and 0.41 GPa, respectively. Pressures calculated using our calibration of the Cr-in-cpx geobarometer are in good agreement between 2-7 GPa, and 900-1400 °C with those estimated from widely-used two-phase geobarometers based on the solubility of alumina in orthopyroxene coexisting with garnet. Application of our updated calibration to suites of well-equilibrated garnet lherzolite and garnet pyroxenite xenoliths and xenocrysts from the Diavik-Ekati kimberlite and the Argyle lamproite pipes confirm the accuracy and precision of our modified geobarometer, and show that PT estimates using our revised geobarometer result in systematically steeper paleogeotherms and higher estimates of the lithosphere?asthenosphere boundary compared with the original NT00 calibration.
DS202105-0794
2021
Yaxley, G.M.Sudholz, Z.I., Yaxley, G.M., Jaques, A.L., Chen, J.Ni-in-garnet geothermometry in mantle rocks: a high pressure experimental recalibration between 1100 and 1325 C. ( diamond potential)Contributions to Mineralogy and Petrology, 176, 16p. PdfMantlegeothermobarometry

Abstract: The temperature-dependent exchange of Ni and Mg between garnet and olivine in mantle peridotite is an important geothermometer for determining temperature variations in the upper mantle and the diamond potential of kimberlites. Existing calibrations of the Ni-in-garnet geothermometer show considerable differences in estimated temperature above and below 1100 °C hindering its confident application. In this study, we present the results from new synthesis experiments conducted on a piston cylinder apparatus at 2.25-4.5 GPa and 1100-1325 °C. Our experimental approach was to equilibrate a Ni-free Cr-pyrope-rich garnet starting mixture made from sintered oxides with natural olivine capsules (Niolv ? 3000 ppm) to produce an experimental charge comprised entirely of peridotitic pyrope garnet with trace abundances of Ni (10-100 s of ppm). Experimental runs products were analysed by wave-length dispersive electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). We use the partition coefficient for the distribution of Ni between our garnet experimental charge and the olivine capsule (lnDNigrt/olv;NigrtNiolv), the Ca mole fraction in garnet (XCagrt; Ca/(Ca?+?Fe?+?Mg)), and the Cr mole fraction in garnet (XCrgrt; Cr/(Cr?+?Al)) to develop a new formulation of the Ni-in-garnet geothermometer that performs more reliably on experimental and natural datasets than existing calibrations. Our updated Ni-in-garnet geothermometer is defined here as: T(?C)=?8254.568((XCagrt×3.023)+(XCrgrt×2.307)+(lnDNigrtolv?2.639))?273±55 where DNigrt/olv=NigrtNiolv, Ni is in ppm, XCagrt = Ca/(Ca?+?Fe?+?Mg) in garnet, and XCrgrt= Cr/(Cr?+?Al) in garnet. Our updated Ni-in-garnet geothermometer can be applied to garnet peridotite xenoliths or monomineralic garnet xenocrysts derived from disaggregation of a peridotite source. Our calibration can be used as a single grain geothermometer by assuming an average mantle olivine Ni concentration of 3000 ppm. To maximise the reliability of temperature estimates made from our Ni-in-garnet geothermometer, we provide users with a data quality protocol method which can be applied to all garnet EPMA and LA-ICP-MS analyses prior to Ni-in-garnet geothermometry. The temperature uncertainty of our updated calibration has been rigorously propagated by incorporating all analytical and experimental uncertainties. We have found that our Ni-in-garnet temperature estimates have a maximum associated uncertainty of ± 55 °C. The improved performance of our updated calibration is demonstrated through its application to previously published experimental datasets and on natural, well-characterised garnet peridotite xenoliths from a variety of published datasets, including the diamondiferous Diavik and Ekati kimberlite pipes from the Lac de Gras kimberlite field, Canada. Our new calibration better aligns temperature estimates using the Ni-in-garnet geothermometer with those estimated by the widely used (Nimis and Taylor, Contrib Mineral Petrol 139:541-554, 2000) enstatite-in-clinopyroxene geothermometer, and confirms an improvement in performance of the new calibration relative to existing versions of the Ni-in-garnet geothermometer.
DS202203-0372
2021
Yaxley, G.M.Yaxley, G.M., Kjarsgaard, B.A., Jaques, A.L.Evolution of carbonatite magmas in the upper mantle and crust.Elements, Vol. 17, pp. 315-320.Mantlecarbonatite

Abstract: Carbonatites are the most silica-poor magmas known and are amongst Earth’s most enigmatic igneous rocks. They crystallise to rocks dominated by the carbonate minerals calcite and dolomite. We review models for carbonatite petrogenesis, including direct partial melting of mantle lithologies, exsolution from silica-undersaturated alkali silicate melts, or direct fractionation of carbonated silicate melts to carbonate-rich residual melts. We also briefly discuss carbonatite-mantle wall-rock reactions and other processes at mid- to upper crustal depths, including fenitisation, overprinting by carbohydrothermal fluids, and reaction between carbonatite melt and crustal lithologies.
DS202205-0717
2022
Yaxley, G.M.Sieber, M.J., Yaxley, G.M., Hermann, J.COH-fluid induced metasomatism of peridotites in the forearc mantle.Contributions to Mineralogy and Petrology, Vol. 177, 44, 10.1007/s00410-022-01905-w.Mantleperidotites

Abstract: Devolatilization of subducting lithologies liberates COH-fluids. These may become partially sequestered in peridotites in the slab and the overlying forearc mantle, affecting the cycling of volatiles and fluid mobile elements in subduction zones. Here we assess the magnitudes, timescales and mechanism of channelized injection of COH-fluids doped with Ca2+aq, Sr2+aq and Ba2+aq into the dry forearc mantle by performing piston cylinder experiments between 1-2.5 GPa and 600-700 °C. Cylindrical cores of natural spinel-bearing harzburgites were used as starting materials. Based on mineral assemblage and composition three reaction zones are distinguishable from the rim towards the core of primary olivine and orthopyroxene grains. Zone 1 contains carbonates?+?quartz?±?kyanite and zone 2 contains carbonates?+?talc?±?chlorite. Olivine is further replaced in zone 3 by either antigorite?+?magnesite or magnesite?+?talc within or above antigorite stability, respectively. Orthopyroxene is replaced in zone 3 by talc?+?chlorite. Mineral assemblages and the compositions of secondary minerals depend on fluid composition and the replaced primary silicate. The extent of alteration depends on fluid CO2 content and fluid/rock-ratio, and is further promoted by fluid permeable reaction zones and reaction driven cracking. Our results show that COH-fluid induced metasomatism of the forearc mantle is self-perpetuating and efficient at sequestering Ca2+aq, Sr2+aq, Ba2+aq and CO2aq into newly formed carbonates. This process is fast with 90% of the available C sequestered and nearly 50% of the initial minerals altered at 650 °C, 2 GPa within 55 h. The dissolution of primary silicates under high COH-fluid/rock-ratios, as in channelized fluid flow, enriches SiO2aq in the fluid, while CO2aq is sequestered into carbonates. In an open system, the remaining CO2-depleted, Si-enriched aqueous fluid may cause Si-metasomatism in the forearc further away from the injection of the COH-fluid into peridotite.
DS202102-0229
2020
Yazawa, E.Wang, W., Yazawa, E., Persaud, S., Myagkaya, E., D'Haenens-Johansson, U., Moses, T.M.Formation of the Matryoshka diamond from Siberia.Gems & Gemology , Vol. 56, 1, pp. 127-129.Russia, Siberiadiamond crystalography

Abstract: A freely moving diamond trapped inside another diamond was discovered in Siberia by Alrosa in 2019. The unusual diamond, nicknamed the “Matryoshka” after the traditional Russian nesting dolls, attracted widespread interest in how this feature formed.
DS1999-0360
1999
Yazeva, R.G.Kholodnov, V.V., Yazeva, R.G.Halogene in petrogensis and mineralizing processes in fossil geodynamic environments of continental margin...Geochemistry International, Vol. 37, No. 7, July pp. 624-31.Russia, UralsBelts - hydpercollisional environments, Tectonics
DS1986-0622
1986
Yazu, S.Onodera, A., Furono, K., Yazu, S.Synthetic diamond as a pressure generatorScience, Vol. 232, June 13, pp. 1419-1420GlobalDiamond morphology
DS1989-1129
1989
Yazu, S.Nisida, Y., Mita, Y., Mori, K., Okuda, S., Sato, S., Yazu, S.Color centers in annealing of neutron irradiated type 1B and 1A diamondsMater. Sci. forum, Vol. 38-41, Proc.Int.defects semicond. 15th.2, 561-565GlobalDiamond morpholoyg, Irradiated
DS1990-1472
1990
Yazu, S.Tomeoka, K., Ozima, M., Zashu, S., Sato, S., Yazu, S.X-ray micro-analysis of micro-inclusions in a Zaire coated diamond21st. Lunar And Planetary Science Conference, March 12-16, Houston, March 16 presentationDemocratic Republic of CongoDiamond morphology, X-ray microscopy
DS1992-1707
1992
YCXu, Shutong, Su W., Liu, YC, Jiang, LLDiamonds from high-pressure metamorphic rocks in eastern Dabie Mountains.*CHIChin. Sci. B., *CHI, Vol. 37, No. 2, January pp. 140-145. # H331ChinaMetamorphic rocks, Dabie Mountains
DS202102-0203
2021
YeLiu, Y., Huang, R., Wu, Ye, Zhang, D., Zhang, J., Wu, X.Thermal equation of state of phase egg ( AlSi03OH): implications for hydrous phases in the deep Earth.Contributions to Mineralogy and Petrology, Vol. 176, 8 doi.org/10.1007 /s00410-020- 01758-1 10p. PdfMantlesubduction
DS1989-1671
1989
Ye, .V.Yeroshenko, V.A., Sharkov, Ye, .V.Thermodynamics of complex systems and their application to magmaticprocessesInternational Geology Review, Vol. 31, No. 10, October pp. 969-985RussiaMagma, Thermodynamics
DS2002-1761
2002
Ye, D-N.Ye, K., Liu, J-B., Cong, B-L., Ye, D-N., Xu, P., Omori, S., Maruyama, S.Ultrahigh pressure (UHP) low Al titanites from carbonate bearing rocks in the Dabie shan Sulu UHP terrane, eastern China.American Mineralogist, Vol. 87, pp. 875-881.ChinaUHP - mineralogy, Dabie Shan area
DS200612-1590
2006
Ye, H.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
DS202110-1646
2021
Ye, H.Zheng, Y., Li, C., Liu, J., Wei, J., Ye, H.Diamond with nitrogen: states, control, and applications.Functional Diamond, Vol. 1, 1, pp. 63-82. doi.org/10.1080/ 26941112.2021.1877021Globalnitrogen

Abstract: The burgeoning multi-field applications of diamond concurrently bring up a foremost consideration associated with nitrogen. Ubiquitous nitrogen in both natural and artificial diamond in most cases as disruptive impurity is undesirable for diamond material properties, eg deterioration in electrical performance. However, the feat of this most common element-nitrogen, can change diamond growth evolution, endow diamond fancy colors and even give quantum technology a solid boost. This perspective reviews the understanding and progress of nitrogen in diamond including natural occurring gemstones and their synthetic counterparts formed by high temperature high pressure (HPHT) and chemical vapor deposition (CVD) methods. The review paper covers a variety of topics ranging from the basis of physical state of nitrogen and its related defects as well as the resulting effects in diamond (including nitrogen termination on diamond surface), to precise control of nitrogen incorporation associated with selective post-treatments and finally to the practical utilization. Among the multitudinous potential nitrogen related centers, the nitrogen-vacancy (NV) defects in diamond have attracted particular interest and are still ceaselessly drawing extensive attentions for quantum frontiers advance.
DS201312-0994
2013
Ye, H-M.Ye, H-M., Li, X-H., Lan, Z-W.Geochemical and Sr-Nd-Hf-O-C isotopic constraints on the origin of the Neoproterozoic Qieganbulake ultramafic carbonatite complex from the Tarim block, northwest China.Lithos, Vol. 182, pp. 150-164.ChinaCarbonatite
DS2001-0694
2001
Ye, K.Liu, J., Ye, K., Maruyama, Cong, FanMineral inclusions in zircon from gneisses in the ultrahigh pressure zone of the Dabie Mountains.Journal of Geology, Vol. 109, pp. 523-35.Chinaultra high pressure (UHP), geochronology, Dabie Shan area
DS2002-1567
2002
Ye, K.Su, W., You, Z., Cong, B., Ye, K., Zhong, Z.Cluster of water molecules in garnet from ultrahigh pressure eclogiteGeology, Vol. 30, No. 7, July pp. 611-14.China, easternUHP eclogite, Dabie Shan Mountains
DS2002-1747
2002
Ye, K.Xu, P., Liu, F., Ye, K., Wang, Q., Cong, B., Chen, H.Flake tectonics in the Sulu Orogen in eastern Chin a as revealed by seismic tomographyGeophysical Research Letters, Vol. 29,10,May15,pp.23-ChinaGeophysics - seismics
DS2002-1761
2002
Ye, K.Ye, K., Liu, J-B., Cong, B-L., Ye, D-N., Xu, P., Omori, S., Maruyama, S.Ultrahigh pressure (UHP) low Al titanites from carbonate bearing rocks in the Dabie shan Sulu UHP terrane, eastern China.American Mineralogist, Vol. 87, pp. 875-881.ChinaUHP - mineralogy, Dabie Shan area
DS2003-1547
2003
Ye, K.Zhang, R.Y., Liou, J.G., Yang, J.S., Ye, K.Ultrahigh pressure metamorphism in the forbidden zone: the Xugou garnet peridotiteJournal of Metamorphic Geology, Vol. 21, 6, pp. 539-50.ChinaUHP
DS200412-1157
2004
Ye, K.Liu, J., Ye, K.Transformation of garnet epidote amphibolite to eclogite, western Dabie Mountains, China.Journal of Metamorphic Geology, Vol. 22, 5, pp. 383-394.ChinaUHP, Dabie Shan
DS200412-2207
2003
Ye, K.Zhang, R.Y., Liou, J.G., Yang, J.S., Ye, K.Ultrahigh pressure metamorphism in the forbidden zone: the Xugou garnet peridotite.Journal of Metamorphic Geology, Vol. 21, 6, pp. 539-50.ChinaUHP
DS200612-0828
2006
Ye, K.Liu, J., Ye, K., Sun, M.Exhumation P T path of UHP eclogites in the Hong'an area, western Dabie Mountains, China.Lithos, Vol. 89, 1-2, June pp. 154-173.ChinaUHP, coesites
DS200712-1203
2007
Ye, K.Ye, K., Song, Y., Wu, J.Upward mantle wedge convection recorded by Zhimafang orogenic garnet lherzolite, Sulu UHP terrane, eastern China.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 258-259.ChinaUHP
DS200712-1204
2007
Ye, K.Ye, K., Song, Y., Wu, J.Upward mantle wedge convection recorded by Zhimafang orogenic garnet lherzolite, Sulu UHP terrane, eastern China.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 258-259.ChinaUHP
DS201112-0177
2011
Ye, K.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
Ye, K.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
DS201112-1136
2011
Ye, L.Ye, L., Li, J., Tseng, T-L., Yao, Z.A stagnant slab in a water bearing transition zone beneath northeast China: implications from regional SH waveform modelling.Geophysical Journal International, Vol. 186, 2, pp. 706-710.ChinaSubduction
DS201112-1137
2011
Ye, L.Ye, L., Tseng, T-L., Yao, Z.A stagnant slab in a water bearing mantle transition zone beneath northeast China: implications from regional SH waveform modelling.Geophysical Journal International, In press available,ChinaSubduction
DS202111-1788
2021
Ye, L.Sun, K., Zhao, Z., Zhang, L., Qiu, L., Liu, X., He, S., Ren, J., Ye, L., Cui, Y.Geochronology, petrography and Sr-Nd-Hf isotopes of Mbalizi carbonatite, southwestern Tanzania.Journal of African Sciences, Vol. 184, 104308, 12p. PdfAfrica, Tanzaniadeposit - Mbalizi

Abstract: The Mbalizi carbonatite is located in the middle of the Paleoproterozoic Ubendian Mobile Belt and the western branch of East Africa Rift, southwestern Tanzania. Calcite, dolomite, phlogopite, pyrochlore and apatite are found in the sample. Mineral chemistry studies have shown that the carbonatite phlogopite is linked to mantle-derived magmatism. The apatite is fluorapatite, means they are of magmatic origin. The analyses on two crystals of pyrochlore show high concentrations of Nb2O5, and therefore the Nb-oxide is classified as pyrochlore subspecies. Three types of zircon have been obtained from the Mbalizi carbonatite, including xenocrysts zircon, igneous zircon and metamorphic zircon. Zircon in-situ LA-ICP-MS U-Pb dating in this contribution indicates that the Mbalizi carbonatite was crystallized at ca. 116.0 ± 1.8 Ma. The ?Hf(t) values of igneous zircon ranging from ?13.9 to +5.7, indicates that the carbonatite parental magma was originated from the sub-continental lithospheric mantle, and evolves toward HIMU and EM. The whole-rock Sr-Nd isotopic data suggest more contribution of the HIMU and EM? material. We propose that the complex evolutionary history of the Ubendian Mobile Belt has stored the subduction oceanic crust which has the EM? and HIMU components, forming the compositional heterogeneity mantle beneath the Ubendian Mobile Belt. At 116.0 ± 1.8 Ma, with the extension stress field, deep faults cause the pressure reduction, resulting in reactive of the upwelling of the HIMU and EM? components. This provides the metamorphic conditions to induce the isotopic resetting and may result in large scatter of initial 176Hf/177Hf ratios of carbonatite melts.
DS200712-0005
2007
Ye, W.Ai,Y., Chen, Q-F., Zeng, F., Hong, X., Ye, W.The crust and upper mantle structure beneath southeastern China.Earth and Planetary Science Letters, Vol. 260, 3-4, pp. 549-563.ChinaTectonics
DS201112-1138
2011
Ye, Yu.Ye, Yu., Smyth, J.R., Frost, D.J.Structural study of the coherent dehydration of wadsleyite.American Mineralogist, Vol. 96, pp. 1760-1767.MantleThermal expansion
DS1993-1793
1993
Ye DelongYe DelongCriteria for discrimination of lamproite and their classification.*CHIDizhi Keji Qingbao, *CHI, No. 12, 1, pp. 39-46.ChinaLamproite, Classification
DS1993-1794
1993
Ye DelongYe DelongCriteria for the discrimination of lamproite and theirclassification.*CHIDizhi Keji Qingbao**CHI, Vol. 12, No. 1, pp. 39-46.ChinaLamproites
DS1991-1908
1991
Ye WeikunYe Weikun, Lu FengxiangThe characteristics and origins of ultrabasic volcanic rocks and their xenoliths from Lixian area, Gansu Province, P.R. of ChinaProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 454-455ChinaFoidite, Ultramafic xenoliths
DS2002-1762
2002
Yeates, G.Yeates, G.The resource and reserve reporting challenge for a global mining company. ( BHP Billiton).Australian Institute of Mining and Metallurgy, No. 3/2002, pp.63-66.AustraliaMineral reserves - definitions, disclosure framework, Regulatory arenas
DS1991-0084
1991
Yeates, M.G.Baxter, J.L., Yeates, M.G., Rowlands, A.T.Estimation of reserves and resources in shear zone hosted depositsAusIMM Proc, Vol. 296, No. 2, Nov. pp. 17-23AustraliaOre reserves, Geostatistics
DS201212-0805
2012
Yeats, C.Yeats, C.Drawing a line in the sand. Seabed mining ( not diamonds but interesting facts).Mining People and Environment, July, pp. 17-19.AustraliaMarine mining
DS1993-1795
1993
Yeats, R.S.Yeats, R.S.Converging more slowly.. Ventura BasinNature, Vol. 366, November 25, pp. 299-300CaliforniaTectonics, Basin
DS200512-1047
2005
Yedekar, D.B.Stephen, J., Singh, S.B., Yedekar, D.B.Evidence of elastic strength variation across the Central Indian Tectonic Zone: a support to the Proterozoic collisional tectonics.Current Science, Vol. 89, 1, pp. 190-194.IndiaTectonics
DS2002-0106
2002
YeeBarreto, A.M., Bezerra, F.H., Suguio, tatumi, Yee, Paiva, MunitaLate Pleistocene marine terrace deposits in northeastern Brasil: sea level change and tectonic implications.Paleogeography Paleoclimatology Palaeoecology, Vol.179,1-2,pp,57-69.Brazil, north eastGeomorphlogy - not specific to diamonds
DS1993-1796
1993
Yefimov, A.A.Yefimov, A.A., Potapova, T.A.high pressure metamorphic rocks of a new type: the lherzolite-gabbro-granulite series in the base of the ultramafic section in the Voykar ophiolite allochthon PolarDoklady Academy of Sciences USSR, Earth Science Section, Vol. 318, No. 6, pp. 148-153.Russia, Commonwealth of Independent States (CIS), Polar UralsOphiolite, Eclogites
DS1985-0750
1985
Yefimov, A.F.Yefimov, A.F., Yeskova, YE.M., Lebedeva, S.I., Levin, V. YA.Type Compositions of Accessory Pyrochlore in a Ural Alkali ComplexGeochemistry International, Vol. 22, No. 1, pp. 68-75RussiaAlkaline Rocks
DS1997-1073
1997
YefimovaSobolev, 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
DS1997-1074
1997
YefimovaSobolev, N.V., Yefimova, Reimers, Zakharchenko, MakhinMineral inclusions in diamonds of the Arkangelsk kimberlite provinceRussian Geology and Geophysics, Vol. 38, No. 2, pp. 379-393.RussiaDiamond inclusions, Deposit - Zolotitsky, Lomonosov, Karpinsky, Pionerskaya
DS1998-1228
1998
YefimovaReimers, L.F., Pokhilenko, Yefimova, SobolevUltramafic mantle assemblages from Sytykanskaya kimberlite pipe, Yakutia7th. Kimberlite Conference abstract, pp. 730-32.Russia, YakutiaXenoliths, mineral chemistry, Deposit - Sytykanskaya
DS1998-1329
1998
YefimovaShatsky, V.S., Zedgenizov, Yefimova, Rylov, De CorteA comparison of morphology and physical properties of microdiamonds From the mantle and crustal environments7th International Kimberlite Conference Abstract, pp. 797-9.Russia, YakutiaDiamond morphology - microdiamonds, Deposit - Udachanya, Sytykanskaya
DS1998-1372
1998
YefimovaSobolev, N.V., Yefimova, Channer, Anderson, BarronUnusual upper mantle beneath Guaniamo, Guyana Shield, Venezuela: evidence from diamond inclusions.Geology, Vol. 26, No. 11, Nov. pp. 971-974.VenezuelaEcogitic, peridotitic, ultrmafic type, Roraima Group
DS1999-0656
1999
YefimovaShatsky, V.S., Zedgenizov, Yefimova, Rylov, De CorteA comparison of morphology and physical properties of microdiamonds from the mantle and crustal environments.7th International Kimberlite Conference Nixon, Vol. 2, pp. 757-63.Russia, Kokchatav Massif, Australia, WesternMicro diamonds, metamorphic rocks, Deposit - Udachnaya, Sytykanskaya
DS2000-0908
2000
YefimovaSobolev, N.V., Sobolev, V.N., Snyder, Yefimova, TaylorSignificance of eclogitic and related parageneses of natural diamonds #2Snyder, Neal, Ernst, Plan. Petrology and Geochemistry, pp. 15-26.GlobalDiamond - morphology, Diamond - genesis
DS2001-0935
2001
YefimovaPokhilenko, N.P., Sobolev, McDonald, Hall, YefimovaCrystalline inclusions in diamonds from kimberlites of the Snap lake area: new evidence anomalous lithosphereDoklady Academy of Sciences, Vol. 381, No. 7, Sept/Oct. pp. 806-11.Northwest TerritoriesDiamond - inclusions, Deposit - Snap Lake
DS1995-1794
1995
Yefimova, E.Sobolev, N.V., Yefimova, E., Reimers, Zakharchenko, MakhinArkhangelsk diamond inclusionsProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 558-560.Russia, ArkangelskDiamond inclusions, Deposit -Lomonosov, Pionerskaya, Karpinski, Pomorskaya
DS1975-0656
1977
Yefimova, E.S.Yefimova, E.S., Bobolev, N.V.Abundance of Crystalline Inclusions in Yakutian DiamondsDoklady Academy of Sciences, Vol. 237, No. 6, pp. 231-4.Russia, Yakutia, SiberiaDiamond Morphology
DS1983-0641
1983
Yefimova, E.S.Yefimova, E.S., Sobolev, N.V., Pospelova, L.N.Sulfide Inclusions in Diamonds and their Paragenesis.(russian)Zap. Vses Mineral. Obshch., (Russian), Vol. 112, No. 3, pp. 300-310RussiaInclusions, Diamond Morphology
DS1984-0695
1984
Yefimova, E.S.Sobolev, N.V., Yefimova, E.S.Dominant calcsilicate association of crystalline inclusions in placer diamonds from southeastern AustraliaDoklady Academy of Science USSR, Earth Science Section, Vol. 274, Jan-Feb. pp. 148-152Australia, InverellPlacers, Inclusions
DS1985-0636
1985
Yefimova, E.S.Sobolev, N.V., Yefimova, E.S., Lavrentyev, YU.G., Sobolev, V.S.Dominant calc-silicate association of crystalline inclusions in placer diamonds from southeastern AustraliaDoklady Academy of Science USSR, Earth Science Section, Vol. 275, April pp. 148-152AustraliaNew South Wales, Diamond Morphology
DS1986-0768
1986
Yefimova, E.S.Sobolev, N.V., Sobolev, E.V., Yefimova, E.S.Some physical and chemical characteristics of diamonds from Copeton New south Wales. Reference to Proceedings 20th.International Gemmological Conference ptThe Australian Gemologist, Vol. 16, No. 3, p. 119. abstractAustraliaDiamond, Morphology
DS1986-0769
1986
Yefimova, E.S.Sobolev, N.V., Yefimova, E.S., Shermanina, E.I.Crystalline inclusions in alluvial diamonds from the Urals, USSRProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, p. 429RussiaDiamond inclusions
DS1989-0463
1989
Yefimova, E.S.Galimov, E.M., Sobolev, N.V., Yefimova, E.S.Isotopic composition of carbon of diamond bearing mineral inclusions From the northern Urals placers.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 9, pp. 1363-1370RussiaDiamond inclusions, Geochronology
DS1989-1378
1989
Yefimova, E.S.Shatsky, V.S., Sobolev, N.V., Yefimova, E.S.Morphological features of accessory microdiamonds from metamorphic Rocks of the earth's crustDiamond Workshop, International Geological Congress, July 15-16th. editors, pp. 94-95. AbstractRussiaMicrodiamond, Metamorphic rocks
DS1989-1422
1989
Yefimova, E.S.Sobolev, N.V., Galimov, E.M., Smith, C.B., Yefimova, E.S., MaltsevA comp study of the morphology, inclusions and C I composition of diamondsSoviet Geology and Geophysics, Vol. 30, No. 12, pp. 1-19AustraliaMicrodiamonds, Alluvial diamonds
DS1989-1426
1989
Yefimova, E.S.Sobolev, N.V., Sobolev, A.V., Pokhilenko, N.P., Yefimova, E.S.Chrome spinels coexisting with Yakutian diamondsDiamond Workshop, International Geological Congress, July 15-16th. editors, pp. 105-108. AbstractRussiaMineral chemistry, Chrome spinels
DS1990-0508
1990
Yefimova, E.S.Galimov, E.M., Sobolev, N.V., Yefimova, E.S., Shemanina, Ye.I.Carbon isotope composition of inclusion bearing diamonds from north UralplacersGeochemistry Int, Vol. 27, No. 4, pp. 131-138RussiaGeochronology CI, Placers
DS1991-1623
1991
Yefimova, E.S.Sobolev, N.V., Bakumenko, I.T., Yefimova, E.S., Pokhilenko, N.P.Morphological features of microdiamonds, sodium in garnet and potassium inpyroxenes content of two eclogite xenoliths from Udachnaya pipe(Yakutia).(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 321, No. 3, pp. 585-592Russia, Commonwealth of Independent States (CIS), YakutiaMicrodiamonds, Udachanya pipe
DS1991-1624
1991
Yefimova, E.S.Sobolev, N.V., Bakumenko, I.T., Yefimova, E.S., Pokhilenko, N.P.Pecularities of microdiamond morphology, sodium content in garnets andDoklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 321, No. 3, pp. 585-592. #hh968RussiaMicro-diamonds, Geochemistry
DS1991-1626
1991
Yefimova, E.S.Sobolev, N.V., Shvedenkov, G.Yu., Korolyuk, V.S., Yefimova, E.S.Nitrogen in chromites and olivines coexisting with diamondDoklady Academy of Science USSR, Earth Science Section, Vol. 309, No. 1-6, July pp. 193-195RussiaNatural diamond, Nitrogen
DS1995-1738
1995
Yefimova, E.S.Shimizu, N., Sobolev, N.V., Yefimova, E.S.Chemical heterogeneities of peridotitic inclusion garnets and juvenility ofdiamonds.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 526-528.Russia, YakutiaGeochemistry, Deposit -Mir, Udachnaya, Aikhal
DS1997-1038
1997
Yefimova, E.S.Shimizu, N., Sobolev, N.V., Yefimova, E.S.Chemical heterogeneities of garnets and juvenile character of peridotitic diamonds from Siberia.Russian Geology and Geophysics, Vol. 38, No. 2, pp. 356-372.Russia, SiberiaGeochemistry, Diamond inclusions, garnet zoning
DS1998-1342
1998
Yefimova, E.S.Shimizu, N., Sobolev, N.V., Yefimova, E.S.Trace element heterogeneities of in situ diamond inclusion garnets fromSiberia.7th International Kimberlite Conference Abstract, p. 807.Russia, SiberiaDiamond inclusions
DS1998-1373
1998
Yefimova, E.S.Sobolev, N.V., Yefimova, E.S., Channer, D., AndersonA unique eclogitic source of Guaniamo diamonds, Guyana Shield, Venezuela7th International Kimberlite Conference Abstract, pp. 829-31.Venezuela, GuyanaEclogites, Diamond genesis
DS1998-1374
1998
Yefimova, E.S.Sobolev, N.V., Yefimova, E.S., Koptil, V.I.Crystalline inclusions in diamonds in the northeast of the Yakutian diamondiferous province.7th International Kimberlite Conference Abstract, pp. 832-4.Russia, YakutiaDiamond inclusions, Deposit - Dianga
DS1999-0693
1999
Yefimova, E.S.Sobolev, N.V., Yefimova, E.S., Koptil, V.I.Mineral inclusions in diamonds in the northeast of the Yakutian Diamondiferous province.7th International Kimberlite Conference Nixon, Vol. 2, pp. 816-22.Russia, Siberia, YakutiaDiamond - inclusions, Deposit - Olenek, Anabar, Lena, Ebelyakh, Dianga
DS2000-0909
2000
Yefimova, E.S.Sobolev, N.V., Yefimova, E.S.Composition and petrogenesis of Ti oxides associated with diamondsInternational Geology Review, Vol. 42, No. 8, pp. 758-RussiaDiamond - inclusions, Petrology
DS2001-1296
2001
Yefimova, E.S.Zedgenizov, D.A., Yefimova, E.S.Ferropericlase inclusions in a diamond microcrystal from the Udachnaya kimberlite pipe Yakutia.Doklady Academy of Sciences, Vol. 3771, March/April pp. 319-21.Russia, YakutiaMicrodiamonds, Deposit - Udachnaya
DS2003-1305
2003
Yefimova, E.S.Sobolev, N.V., Loginova, A.M., Yefimova, E.S., Zedgenizov, D.A., Channer, D.Polymineralic eclogite inclusions in Guaniamo diamonds, Venezuela: evidence for8ikc, Www.venuewest.com/8ikc/program.htm, Session 2, POSTER abstractVenezuelaEclogites and Diamonds, Deposit - Guaniamo
DS2003-1306
2003
Yefimova, E.S.Sobolev, N.V., Loginova, A.M., Zedgenizov, D.A., Yefimova, E.S., Taylor,L.A.Mineral inclusions in diamonds from the Komsomolskaya and Krasnopresnenskaya8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractRussia, SiberiaDiamonds - inclusions, Deposit - Komosomolskaya, Krasnopresnenskaya
DS2003-1307
2003
Yefimova, E.S.Sobolev, N.V., Logvinova, A.M., Zedgenizov, D.A., Yefimova, E.S.Mineral inclusions in microdiamonds and macrodiamonds from kimberlites of Yakutia: a8 Ikc Www.venuewest.com/8ikc/program.htm, Session 3, AbstractRussia, Yakutia, SiberiaDiamonds - inclusions
DS200412-1870
2003
Yefimova, E.S.Sobolev, N.V., Logvinova, A.M., Zedgenizov, D.A., Yefimova, E.S.Mineral inclusions in microdiamonds and macrodiamonds from kimberlites of Yakutia: a comparative study.8 IKC Program, Session 3, AbstractRussia, Yakutia, SiberiaDiamonds - inclusions
DS1996-1347
1996
Yefimova, Ye. A.Sokolv, B.A., Piyp, V.B., Yefimova, Ye. A.Basement structure in the centre of the East European Craton, as inferred from seismic data.Doklady Academy of Sciences, Vol. 336, pp. 72-78.Russia, Arkangelsk, EuropeBasement -depth, Geophysics -seismics
DS1984-0591
1984
Yefimova, YE.S.Pokhilenko, N.P., Sobolev, N.V., Yefimova, YE.S.Xenolith of Broken Down Diamond Bearing Kyanite Eclogite From the Udachnaya Pipe, Yakutia.Doklady Academy of Science USSR, Earth Science Section., Vol. 266, No. 1-6, MAY PP. 90-94.Russia, YakutiaLherzolite, Geothermometry, Genesis, Diamond Morphology
DS1989-0760
1989
Yefremova, L.B.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
DS1991-0196
1991
Yegorkin, A.V.Bulin, N.K., Yegorkin, A.V.The application of seismic dat a to explore kimberlite magma regions of the northern Russian Platform*(in Russian)Sovetskaya Geologiya, (Russian), No. 10, pp. 82-91RussiaGeophysics -seismics, Timan-Pechora region
DS1986-0004
1986
Yegorov, A.Y.Afanasyev, V.P., Sibertsev, Y.M., Yegorov, A.Y.Minerals from kimberlites in ancient littoral reservoir rocks. (Russian)Izv. Vysshikh Uchn. Zaved. Geol. I Razveda (Russian), Vol. 2, pp. 48-54RussiaPetrology, Mineral chemistry
DS1998-1617
1998
Yegorov, D.G.Yegorov, D.G., et al.CHEMPET - calculation for the chemical systematics of igneous rocks Based on the CIPW norm.Computers and Geosciences, Vol. 24, No. 1, pp. 1-5GlobalAlkaline rocks, igneous petrology, Computer - program, CHEMPET.
DS1988-0126
1988
Yegorov, I.I.Chernysheva, Ye. A., Yegorov, I.I.Intrusive origin of melilitic rocks of the eastern SayanDoklady Academy of Science USSR, Earth Science Section, Vol. 290, No. 1-6, March pp. 152-153RussiaAlkalic complexes, Analyses
DS1980-0195
1980
Yegorov, I.S.Kravchenko, S.M., Yegorov, I.S., et al.Rare Earths and Strontium in Apatites As Indicators of Rock genesis for the Ultramafic Alkaline Formation of the Maymecha-kotny Province.Geochemistry International (Geokhimiya)., 1980, No. 12, PP. 1835-1843.RussiaRare Earth Elements (ree)
DS1987-0821
1987
Yegorov, I.V.Yegorov, I.V.Use of geomorphologic methods for the study of kimberlite fields.(Russian)Vestnik Leningradskogo Universiteta, Geol. Geogr., (Russian), Vol. 1987, No. 3, pp. 103-107RussiaGeomorphology
DS1988-0771
1988
Yegorov, I.V.Yegorov, I.V., Sorokin, M.Yu., Yaskevich, V.G.The experience of structural geomorphological studies in predicting kimberlite spatial distribution.(Russian)Geomorfologiya, (Russian), Vol. 1988, No. 3, pp. 24-28RussiaPetrology, Geomorphology
DS1990-1611
1990
Yegorov, I.V.Yegorov, I.V.Geomorphological methods in the exploration of kimberlite bodies.(Russian)Geomorfologiya, (Russian), Vol. 1990 No. 4, December pp. 24-31RussiaRemote sensing, Lineaments
DS1993-1797
1993
Yegorov, I.V.Yegorov, I.V.Geomorphological analysis of kimberlite bearing areas.(Russian)Geomorpholgiya, (Russian), Vol. 1993, No. 4, pp. 89-96.RussiaGeomorphology, Kimberlites
DS1981-0436
1981
Yegorov, K.N.Yegorov, K.N., et al.Study Methods and the Processing of Factual MaterialsIn: Odintsov, M.m. Editor., PP. 6-13.RussiaBlank
DS1982-0343
1982
Yegorov, K.N.Kostovitskiy, S.I., Yegorov, K.N.Development Mechanism of Kimberlite Pipe ChannelsVulkanologiya I Seismologiya., Vol. 1982, No. 1, PP. 3-12.RussiaBlank
DS1983-0642
1983
Yegorov, K.N.Yegorov, K.N.Sequence of olivine crystallization at the mantle stage ofkimberliteformation.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 271, No. 1, pp. 174-178RussiaMantle
DS1984-0491
1984
Yegorov, K.N.Maslovskaya, M.N., Yegorov, K.N., Kolosnitsyna, T.I., Brandt, S.Strontium Isotope Distribution Rubidium Strontium Age and Rare Alkalies of Micas from Yakutian Kimberlites.Doklady Academy of Science USSR, Earth Science Section., Vol. 266, No. 1-6, MAY PP. 149-152.RussiaGeochronology, Mir, Udachnaya
DS1984-0625
1984
Yegorov, K.N.Safronov, A.F., Yegorov, K.N., Makhotko, V.F.Thermal Regime of Crystallization of Kimberlite MeltDoklady Academy of Science USSR, Earth Science Section., Vol. 269, No. 1-6, SEPT. PP. 119-121.RussiaUdachnaya, Crystallography, Mineralogy
DS1985-0751
1985
Yegorov, K.N.Yegorov, K.N.Contact relationships between kimberlite injection phases in pipes with complex structuresInternational Geology Review, Vol. 27, No. 10, October pp. 1179-1191RussiaChemical Analyses
DS1985-0752
1985
Yegorov, K.N.Yegorov, K.N.Contact inter relations of kimberlites of different injection phases incomplex pipes.(Russian)Izvest. Akad. Nauk SSSR, ser. geol., (Russian), No. 9, pp. 23-35RussiaPetrography, Geology
DS1985-0753
1985
Yegorov, K.N.Yegorov, K.N.Mineral inclusions in basic minerals of kimberlites from Yakutia and their genetic importance.(Russian)Zapis. Vses. Mineral. Obshch., (Russian), Vol. 114, No.2, pp. 178-186RussiaPetrology
DS1985-0754
1985
Yegorov, K.N.Yegorov, K.N.The genetic significance of mineral inclusions in major minerals of YakutiakimberlitesInternational Geology Review, Vol. 27, No. 7, July pp. 824-833RussiaUdachnaya-vostochnaya Pipe, Paragenesis, Inclusions
DS1986-0883
1986
Yegorov, K.N.Yegorov, K.N.Modification of the isotopic composition of hydrogen and oxygen during the metasomatic transformation of kimberlites.(Russian)Doklady Academy of Sciences Nauk SSR, (Russian), Vol. 286, No. 2, pp. 429-433RussiaBlank
DS1986-0884
1986
Yegorov, K.N.Yegorov, K.N., Kornilova, V.P., Safonov, A.F., Filippov, N.D.Mica kimberlites in the Udachnaya-Vostochnaya pipe. (Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 291, No. 1, pp. 199-202RussiaMica, Deposit -Udachnaya
DS1987-0822
1987
Yegorov, K.N.Yegorov, K.N.Variation in carbon and oxygen isotope composition during metasomatic alteration of kimberliteDoklady Academy of Science USSR, Earth Science Section, Vol. 285, No. 6, pp. 175-178RussiaBlank
DS1989-1668
1989
Yegorov, K.N.Yegorov, K.N., Vladimirov, B.M., Zaborovskiy, V.V., et al.Find of a potassic trachyte dike near the Udachnaya kimberlite pipe, Yakutia #1Doklady Academy of Science USSR, Earth Science Section, Vol. 298, No. 1-6, pp. 116-119RussiaDeposit -Udachnaya, Trachyte dike
DS1989-1669
1989
Yegorov, K.N.Yegorov, K.N., Vladimirov, B.M., Zaborovskiy, V.V., NasurdinovFind of a potassic trachyte dike near the Udachnaya kimberlite pipe, Yakutia #2Doklady Academy of Science USSR, Earth Science Section, Vol. 298, No. 1-6, April pp. 116-118RussiaPetrography, Trachyte
DS1990-1612
1990
Yegorov, K.N.Yegorov, K.N., Bogdanov, G.V., Paradina, L.F.Main regularities of the chemistry of serpentinization of kimberlites.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 315, No. 5, pp. 1213-1217RussiaGeochemistry, Serpentinization -kimberlites
DS1991-1909
1991
Yegorov, K.N.Yegorov, K.N., Bogdanov, G.V., Zavyalov, L.L.New dat a on the kimberlite composition of the Zagadochnaya pipe(Yakut).(Russian)Izvest. Akad. Nauk SSS, Geol., (Russian), No. 11, November pp. 98-108Russia, YakutiaKimberlite, Zagadochnaya mineralogy
DS1992-1720
1992
Yegorov, K.N.Yegorov, K.N., Bogdanov, G.V., Pardina, L.F.The chemistry of the serpentinization of kimberliteDoklady Academy of Sciences USSR, Earth Science Section, Vol. 315, pp. 194-198.RussiaKimberlite, Alteration -serpentine
DS1995-2102
1995
Yegorov, K.N.Yegorov, K.N., Bezborodov, S.M., Mazilov, V.N.Volcanogenic sedimentary xenoliths in the Udacahnaya kimberlite pipeDoklady Academy of Sciences, Vol. 329, No. 2, Jan. pp. 109-113.RussiaXenoliths, Deposit -Udachanaya
DS1960-1053
1968
Yegorov, L.S.Yegorov, L.S., Rudyachenok, V.M., Surina, N.P.Tectonic Position of Ultrabasic Alkalic Rocks in the Maymecha-kotuy Province.Doklady Academy of Science USSR, Earth Science Section., Vol. 182, No. 1-6, PP. 19-22.RussiaKimberlite
DS1984-0785
1984
Yegorov, L.S.Yegorov, L.S.Rare Earth Element and Fluorine Contents of Apatite As Reflecting Formation Conditions, Alteration and Potential Mineralization for Rocks of the Foscorite Carbonatite.Geochemistry International (Geokhimiya), Vol. 21, No. 1, PP. 93-107.RussiaRare Earth Elements (ree), Carbonatite
DS1984-0786
1984
Yegorov, L.S.Yegorov, L.S.Relative Age of Melilite Rocks in Ijolite Carbonatite Plutons of the Karelia Kola Region.Doklady Academy of Science USSR, Earth Science Section., Vol. 265, No. 106, PP. 86-88.RussiaRelated Rocks
DS1985-0234
1985
Yegorov, L.S.Gilinskaya, L.G., Yegorov, L.S.Esr Spectra of Apatite from the Maymecha-kotuy IjolitecarbonatitecomplexGeochemistry International, Vol. 22, No. 5, pp. 1-8RussiaCarbonatite, Ijolite
DS1985-0755
1985
Yegorov, L.S.Yegorov, L.S.Alkaline Ultramafic Magmatism and Its Mineralization.(russian)Geol. Rudny. Mest., (Russian), Vol. 27, No. 4, pp.24-40RussiaMelilitite, Kimberlite
DS1989-1670
1989
Yegorov, L.S.Yegorov, L.S.Form, structure and development of the Guli ultramafic-alkalic and carbonatite plutonInternational Geology Review, Vol. 31, No. 12, December pp. 1226-1239RussiaCarbonatite, Guli
DS1993-0402
1993
Yegorov, L.S.Egorov, L.S., Yegorov, L.S., et al.Prospects of mineral detection associated with alkaline-ultrabasic rocks(Prince Charles Mountains).International Gondwana Symposium, III, Editors Findlay, Vol. 8, pp. 559-562.GlobalLamproite, Kimberlite, diamonds
DS1993-1798
1993
Yegorov, L.S.Yegorov, L.S.Phoscorites of the Maymecha-Kotuy ijolite carbonatite associationInternational Geology Review, Vol. 35, No. 4, April pp. 346-358.RussiaCarbonatite, Phoscorite -previously kamaforite
DS1994-1964
1994
Yegorov, L.S.Yegorov, L.S.Petrogeochemical and petrogenetic features of hypabyssal alkali ultrabasites Jetty Oasis PolzeniteGeochemistry International, Vol. 31, No. 8, pp. 24-40.AntarcticaPicrites, Prince Charles Mountains
DS1995-2103
1995
Yegorov, L.S.Yegorov, L.S., Melnik, A.Yu., Ukhanov, A.V.The first Antarctic occurrence of a dike kimberlite containing syngenetic calcite carbonatite schlieren.Doklady Academy of Sciences, Vol. 329, No. 2, Jan. pp. 104-108.AntarcticaKimberlite, Dike
DS1988-0772
1988
Yegorov, N.K.Yegorov, N.K., Ushchapovskaya, Z.F., Kashayev, A.A., et al.Zemkorite, a new carbonate from kimberlites of YakutiaDoklady Academy of Science USSR, Earth Science Section, Vol. 301, No. 4, July-Aug. pp. 142-146RussiaMineralogy, Zemkorite
DS1960-0467
1964
Yegorov, O.S.Koval'skiy, V.V., Yegorov, O.S.The Content of Xenoliths in Explosive Kimberlite Breccias And a Method of Calculating It.Geologii i Geofiziki, No. 11, PP. 140-143.RussiaBlank
DS1970-0218
1970
Yegorov, O.S.Zolnikov, G.V., Yegorov, O.S.Eutaxitic Structure of Kimberlites from Some Yakutian PipesGeologii i Geofiziki, No. 5, PP. 64-7L.RussiaBlank
DS1991-0056
1991
Yegorov, O.S.Balashov, Yu.A., Yegorov, O.S., Kolesov, G.M.The rare earth elements (REE) in Middle Bug basic and ultrabasic rocksGeochemistry International, Vol. 27, No. 10, pp. 124- 129RussiaHarzburgites -analyses, rare earth elements (REE) indicators
DS1983-0526
1983
Yegorova, N.F.Pyatenko, I.K., Yegorova, N.F., Zilberman, A.M., Chernysheva, YE. M.Immiscibility as a possible factor in the genesis of melanocratic members of the basaltseries, as illustrated by the central Ural rock complexDoklady Academy of Science USSR, Earth Science Section, Vol. 273, Nov. Dec. pp. 104-107RussiaPetrology Similar To Kimberlites
DS1985-0550
1985
Yegorova, N.F.Pyatenko, I.K., Yegorova, N.F., Zilberman, A.M., Chernysheva, Y.Immiscibility as a Possible Factor in the Genesis of MelanocDoklady Academy of Science USSR, Earth Science Section., Vol. 273, No. 1-6, PP. 104-107.Russia, UralsPicrite, Chemical Composition, Textures
DS200712-1044
2006
Yegorova, T.Stephenson, R.A., Yegorova, T., Brunet, M.F., Stovba, S., Wilson, M., Starostenko, V., Saintot, A., Kusznir, N.Late Paleozoic intra- and pericratonic basins on the East European Craton and its margins.Geological Society of London Memoir, No. 32, pp. 463-480.Europe, Baltic ShieldCraton
DS200412-2180
2004
Yegorova, T.P.Yegorova, T.P., Stephenson, R.A., Kostyuchenko, S.L., Baranova, E.P., Satrostenko, V.I., Popolitov, K.E.Structure of the lithosphere below the southern margin of the East European Craton ( Ukraine and Russia) from gravity and seismiTectonophysics, Vol. 381, 1-4, pp. 81-100.Europe, UkraineTectonics
DS1984-0590
1984
Yegranova, I.G.Podvysotskiy, V.T., Yegranova, I.G., Feoktistova, L.P.Magnetite in KimberliteDoklady Academy of Science USSR, Earth Science Section., Vol. 266, No. 1-6, MAY PP. 157-159.RussiaMineralogy, Inclusions, Udachanaya, Malaya Botuobuya, Daldyn
DS202103-0405
2021
Yegres, L.Schmitz, M., Ramirez, K., Mazuera, F., Avila, J., Yegres, L., Bezada, M., Levander, A.Moho depth map of northern Venezuela on wide-angle seismic studies.Journal of South American Earth Sciences, Vol. 107, 103088, 17p. PdfSouth America, VenezuelaGeophysics - seismics

Abstract: As part of the lithosphere, the crust represents Earth's rigid outer layer. Some of the tools to study the crust and its thickness are wide-angle seismic studies. To date, a series of seismic studies have been carried out in Venezuela to determine in detail the crustal thickness in the southern Caribbean, in the region of the Caribbean Mountain System in northern Venezuela, as well as along the Mérida Andes and surrounding regions. In this study, a review of the wide-angle seismic data is given, incorporating new data from the GIAME project for western Venezuela, resulting in a map of Moho depth north of the Orinoco River, which serves as the basis for future integrated models. Differences in Moho depths from seismic data and receiver function analysis are discussed. From the Caribbean plate, Moho depth increases from 20 to 25 km in the Venezuela Basin to about 35 km along the coast (except for the Falcón area where a thinning to less than 30 km is observed) and 40-45 km in Barinas - Apure and Guárico Basins, and Guayana Shield, respectively. Values of more than 50 km are observed in the Maturín Basin and in the southern part of the Mérida Andes.
DS1991-1910
1991
Yehuda, Z.Yehuda, Z.Fracture filling of diamondsInternational Gemological Symposium, June 20-24, 1991 Los Angeles, Gems and Gemology, Vol. 27, Spring, Program p. 1GlobalDiamond morphology
DS1992-1721
1992
Yekimova, T.V.Yekimova, T.V., Lavrova, L.D., Petrova, M.A.Diamond inclusions in rock-forming minerals of metamorphic rocks.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 322, No. 2, pp. 366-368RussiaDiamond inclusions, Metamorphic rocks
DS1987-0440
1987
Yekimova, T.Y.Martovitsky, V.P., Nedezhdina, Y.D., Yekimova, T.Y.Internal structure and morphology of small non-kimberlitediamonds.(Russian)Mineralog. Zhurnal, (Russian), Vol. 9, No. 2, April pp. 26-37RussiaCrystallography
DS1994-1965
1994
Yekimova, T.Ye.Yekimova, T.Ye., Lavrova, L.D., Petrova, M.A.Diamond inclusions in the rock forming minerals of metamorphic rocksDoklady Academy of Sciences Acad. Science USSR, Vol. 323, No. 2, June pp. 101-103.RussiaDiamond inclusions, Metamorphic rocks
DS1990-1526
1990
Yelisafenko, V.N.Vrublevskiy, V.V., Babanskiy, A.D., Troneva, N.V., Yelisafenko, V.N.Minerogenesis conditions of carbonatites of Kuznetsk Alatau.(Russian)Izv. Akad. Nauk SSSR Ser. Geol., (Russian), No. 12, pp. 65-81RussiaCarbonatite, Mineralogy
DS2003-1529
2003
Yeliseev, A.P.Yeliseev, A.P., Pkhilenko, N.P., Zedgenizov, D.A., Steeds, J.Features of coated diamonds from the Snap Lake King Lake kimberlite dyke system8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractNorthwest TerritoriesDiamonds - inclusions, Deposit - Snap Lake, King Lake
DS200712-1124
2006
Yeliseyev, A.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
DS1994-1966
1994
Yeliseyev, A.P.Yeliseyev, A.P., Nadolinnyy, V.A.New nickel containing paramagnetic centers in diamondDoklady Academy of Sciences USSR, Vol. 327, Oct. pp. 149-154.Russia, SiberiaDiamond morhology, Nickel Spectroscopy
DS1987-0383
1987
Yeliseyeva, S.V.Krutikhovskaya, Z.A., Yeliseyeva, S.V., Negrutsa, V.Z., SlivinskayaRegional magnetic anomalies of old shields and platforms as indicators of early Precambrian rift troughsDoklady Academy of Science USSR, Earth Science Section, Vol. 288, No. 1-6, pp. 72-75RussiaBlank
DS201312-0995
2013
Yelisseyev, A.Yelisseyev, A., Meng, G.S., Afanasyev, V., Pokhilenko, N., Pustovarov, V., Isakova, A., Lin, Z.S, Lin, H.Q.Optical properties of impact diamonds from the Popigai astroblemes.Diamond and Related Materials, Vol. 37, pp. 8-16.Russia, SiberiaMeteortic diamonds
DS201412-1007
2014
Yelisseyev, A.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
Yelisseyev, A.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
Yelisseyev, A.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.
DS202112-1922
2021
Yelisseyev, A.Chepurov, A., Sonin, V., Shcheglov, D., Zhimulev, E., Sitnikov, S., Yelisseyev, A., Chepurov, A.Surface porosity of natural crystals after the catalytic hydrogenation.Crystals, Vol. 11, 1341 9p pdfRussiadeposit - Popigai

Abstract: The study of diamond surfaces is traditionally undertaken in geology and materials science. As a sample material, two natural diamond crystals of type Ia were selected, and their luminescence and nitrogen state was characterized. In order to etch the surface catalytic hydrogenation was performed using Fe particles as an etchant. Micromorphology of the surface was investigated by scanning electron and laser confocal microscopy. It was demonstrated that etching occurred perpendicular to the crystal surface, with no signs of tangential etching. The average depth of caverns did not exceed 20-25 ?m with a maximal depth of 40 ?m. It is concluded that catalytic hydrogenation of natural type Ia diamonds is effective to produce a porous surface that can be used in composites or as a substrate material. Additionally, the comparison of results with porous microsculptures observed on natural impact diamond crystals from the Popigai astrobleme revealed a strong resemblance.
DS200912-0839
2009
Yelisseyev, A.A.P.A.Yelisseyev, A.A.P.A., Afanasiev, V.A.P.A., Ikorsky, V.A.N.A.Magnetic susceptibility of natural diamonds.Doklady Earth Sciences, Vol. 425, 2, pp. 330-333.TechnologyDiamond morphology
DS200412-2181
2004
Yelisseyev, A.P.Yelisseyev, A.P., Pokhilenko, N.P., Steeds, J.W., Zedgenizov, D.A., Afanasiev, V.P.Features of coated diamonds from the Snap Lake/King Lake kimberlite dyke, Slave Craton, Canada, as revealed by optical topographLithos, Vol. 77, 1-4, Sept. pp. 83-97.Canada, Northwest TerritoriesCoated diamonds, absorption, luminescence, nickel, nitr
DS200512-0760
2004
Yelisseyev, A.P.Nadolinnyi, V.A., Yreva, O.P., Yelisseyev, A.P., Pokhilenko, N.P., Chepurov, A.A.Disruption of B1 nitrogen defects in 1aB natural diamonds.Doklady Earth Sciences, Vol. 399A, Nov-Dec. pp. 1228-1272.Diamond morphology
DS201212-0045
2012
Yelisseyev, A.P.Baich, Yu.V., Feigelson, B.N., Yelisseyev, A.P., Chepuov, A.I.Nitrogen in corporation in octahedral diamonds grown in the Fe-Ni-C systemGeochemistry International, Vol. 50, 2, pp. 179-184.TechnologyDiamond genesis
DS201212-0806
2012
Yelisseyev, A.P.Yelisseyev, A.P., Afanasiev, V.P., Kopylova, M.G., Bulbak, T.A.The effect of metamorphic annealing and Betairradiation in optical properties of type 1AA diamonds.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, Ontario, RussiaDiamond - metamorphism
DS201502-0074
2015
Yelisseyev, A.P.Logvinova, A.M., Taylor, L.A., Fedorova, E.N., Yelisseyev, A.P., Wirth, R., Howarth, G., Reutsky, V.N., Sobolev, N.V.A unique Diamondiferous peridoite xenolith from the Udachnaya kimberlite pipe, Yakutia: role of subduction in diamond formation.Russian Geology and Geophysics, Vol. 56, 1, pp. 306-320.Russia, YakutiaDeposit - Udachnaya
DS201610-1910
2016
Yelisseyev, A.P.Sobolev, N.V., Wirth, R., Logvinova, A.M., Yelisseyev, A.P., Kuzmin, D.V.Retrograde isochemical phase transformations of majoritic garnets included in diamonds: a case study of subcalcic Cr-rich majoritic pyrope from a Snap Lake diamond, Canada.Lithos, in press available 11p.Canada, Northwest TerritoriesDeposit - Snap Lake

Abstract: Homogeneity of a peridotitic garnet inclusion in diamond demonstrating excess in Si concentration (i.e. presence of majorite component) was investigated by TEM using FIB prepared foils. The host diamond is a low-nitrogen brown stone, which can be related to type IIa with features of strong plastic deformation. The studied sample is represented by Ca-poor Cr-pyrope of harzburgitic (H) paragenesis from Snap Lake dyke, Canada The garnet had been previously reported to contain Si = 3.16 apfu. The revised examination of the sample, resulted in detection of extremely fine-grained symplectite consisting of low Ca-orthopyroxene, clinopyroxene, Cr-spinel and coesite completely located and isolated in the inner part of the garnet crystal, which forms a sharp interface with the surrounding homogeneous garnet. XRD study confirmed the presence of the minerals constituting the symplectite. EPMA showed an identical bulk chemistry of the nanometer-sized symplectite and garnet. Further polishing of the garnet inclusion on the same surface with diamond removed the symplectite, which possibly was present as a thin lens within garnet. The remaining garnet is completely homogeneous as checked by two profiles, and contains unusually high Ni (118.2 ppm) and depleted REE patterns. Estimated PT formation conditions of this garnet are 10.8 GPa and 1450 °C within asthenosphere. Symplectite testifies partial retrograde isochemical phase transformation of the examined garnet which is suggested to be caused by decompression along with plastic deformation of diamond within the coesite stability field at T > 1000 °C and depth no less than 100 km. Because previously published studies of rare majoritic garnets composition were performed by EPMA only, it is possible that the traces of partial phase transformation (symplectite formation) could have been overlooked without additional XRD and/or TEM/AEM studies.
DS201610-1919
2016
Yelisseyev, A.P.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.
DS201812-2901
2018
Yelisseyev, A.P.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.
DS201112-1139
2010
Yellapa, T.Yellapa,T., Chalapathi Rao, N.V., Chetty, T.R.K.Occurrence of lamproitic dykes at the margin of the Indravati Basin, Bastar Craton, central India.Journal of the Geological Society of India, Vol. 75, 4, pp. 632-643.IndiaLamproite
DS201012-0873
2010
Yellappa, T.Yellappa, T., Chapalapthi Rao, N.V., Chetty, T.R.K.Occurrence of lamproitic dykes at the northern margin of the Indravati Basin, Bastar Craton, central India.Journal of the Geological Society of India, Vol. 75, 4, April pp. 632-643.IndiaLamproite
DS201112-1140
2010
Yellappa, T.Yellappa, T., Chalapathi Rao, N.V., Chetty, TRK.Occurrence of lamproitic dykes at the northern margin of the Indravati basin, Bastar Craton, central India.Journal of the Geological Society of India, Vol. 75, pp. 632-643.India, ChhattisgarhLamproite
DS200812-1298
2007
Yellowknife Geoscience Forum, 35th.Yellowknife Geoscience Forum, 35th.Each diamond relevant abstract cited seperately35th. Yellowknife Geoscience Forum, Abstracts only p.CanadaAstracts only
DS1994-1967
1994
YellowkniferYellowkniferBad news doesn't end diamond prospectsYellowknifer, Wed. Aug. 10, p. 7.Northwest TerritoriesNews item, DHK, Kennecott
DS201012-0678
2010
Yelowitz, A.Scott, F., Yelowitz, A.Pricing anomalies in the market for diamonds: evidence of conformist behavior.Economic Enquiry ( Blackwell Pub.), Vol. 48, 2, pp. 353-368. IngentaGlobalEconomics
DS200612-1569
2005
Yelpaala, K.Yelpaala, K., Ali, S.H.Multiple scales of diamond mining in Akwatia, Ghana: addressing environmental and human development impact.Resources Policy, Vol. 30, 3, pp. 145-155.Africa, GhanaSocial environment
DS1998-1488
1998
Yelpi, L.Z.Tulcanaza Navarro, E., Yelpi, L.Z.Options for hedging mine planning scenerios to meet contingenciesEngineering and Mining Journal, Vol. 199, No. 5, May pp. 56-60GlobalEconomics, discoveries, risk, options, Hedging
DS1998-1492
1998
Yelpi, L.Z.Tuscanaza Navaro, E., Yelpi, L.Z.Options for hedging.. mine planning scenarios to meet contingencies.PartIII of IIIEngineering and Mining Journal, Vol. 199, No. 7, July pp. 46-49GlobalEconomics, mining, reserves, cost/price, discoveries
DS1991-1911
1991
Yelutin, A.V.Yelutin, A.V., Polyakov, V.P., Chernykh, R.O.Solubility of graphite and diamond in NIMN melt under the high pressure.(Russian)Doklady Academy of Sciences Nauk SSR, (Russian), Vol. 320, No. 4, pp. 864-867RussiaExperimental petrology, Graphite
DS1981-0437
1981
Yelyanov, M.D.Yelyanov, M.D., Timoshenko, I.L., Shevchenko, B.YE.The Weathering Mantle Section of CarbonatitesGeol. Zhurn., Vol. 41, No. 3, PP. 69-77.RussiaGeomorphology
DS1991-1048
1991
Yemelyanenko, Ye.P.Marakushev, A.A., Yemelyanenko, Ye.P., et al.Formation of the concentrically zoned structure of the Konderalkalic-ultrabasic plutonDoklady Academy of Science USSR, Earth Science Section, Vol. 311, Nove. 1-6, pp. 69-72RussiaAlkaline rocks, Konder
DS1988-0773
1988
Yemelyanov, V.N.Yemelyanov, V.N., Sibirtsev, Yu.M.Applying magnetic surveys to the exploration of buried ancientreservoirs.(Russian)Razv. I Okhr. Nedr. (Russian), No. 10, pp. 57-59RussiaYakutia, Geophysics
DS1993-1799
1993
Yen-Hong ShauYen-Hong Shau, Peacor, D.R., Essene, E.J.Formation of magnetic single-domain magnetite in ocean ridge basalts with implications for sea floor magnetismScience, Vol. 261, July 16, pp. 343-345Sea floorRifting, Tectonics
DS200512-0506
2004
Yeo, G.Kelley, L., Yeo, G.Preliminary investigation: sedimentology and provenance of the Wood Mountain Formation and derived glacial and glaciofluival sediments - context for KIM anomalies.Saskatchewan Geological Survey Summary of Investigations 2004, Vol. 2, pp. A 1-12.Canada, SaskatchewanKimberlite indicator minerals, geochemistry
DS201906-1355
2019
Yeow, H.Timmerman, S., Yeow, H., Honda, M., Howell, D., Jaques, A.L., Krebs, M.Y., Woodland, S., Pearson, D.G., Avila, J.N., Ireland, T.R.U-Th/He systematics of fluid rich 'fibrous' diamonds - evidence for pre- and syn-kimberlite eruption ages.Chemical Geology, Vol. 515, pp. 22-36.Africa, Democratic Republic of Congo, Botswanadeposit - Jwaneng

Abstract: The physical characteristics and impermeability of diamonds allow them to retain radiogenic 4He produced in-situ from radioactive decay of U, Th and Sm. This study investigates the U-Th/He systematics of fibrous diamonds and provides a first step in quantification of the uncertainties associated with determining the in-situ produced radiogenic 4He concentration. Factors determining the total amount of measured helium in a diamond are the initial trapped 4He, the in-situ produced radiogenic 4He, ?-implantation, ?-ejection, diffusion, and cosmogenic 3He production. Alpha implantation is negligible, and diffusion is slow, but the cosmogenic 3He component can be significant for alluvial diamonds as the recovery depth is unknown. Therefore, samples were grouped based on similar major and trace element compositions to determine possible genetically related samples. A correlation between the 4He and U-Th concentrations approximates the initial 4He concentration at the axis-intersect and age as the slope. In this study, the corrections were applied to eight fibrous cubic diamonds from the Democratic Republic of the Congo and two diamonds from the Jwaneng kimberlite in Botswana. A correlation exists between the 4He and U-Th concentrations of the group ZRC2, 3, and 6, and of the group CNG2, 3, and 4 and both correlations deviate significantly from a 71?Ma kimberlite eruption isochron. The U-Th/He dating method appears a promising new approach to date metasomatic fluid events that result in fibrous diamond formation and this is the first evidence that some fibrous diamonds can be formed 10s to 100s Myr before the kimberlite eruption.
DS1996-1141
1996
Yepes, H.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
DS1984-0787
1984
Yepishina, N.I.Yepishina, N.I., Nadezhdina, Y.D., Klyuyev, Y.A., Naletov.Hardness, viscosity and defects due to the fragility of continuousnatural lonsdaleite in natural diamonds.(Russian)Doklady Academy of Sciences Nauk. SSSR (Russian), Vol. 276, No. 1, pp. 232-234RussiaDiamond, Morphology
DS1986-0885
1986
Yepishina, N.I.Yepishina, N.I., Nadezhdina, Ye.D., Klyuyev, Yu.A., et al.Hardness and toughness in brittle fracture of natural lonsdaleite-containing polycrystalline diamondDoklady Academy of Science USSR, Earth Science Section, Vol. 276, No. 1-6, pp. 112-114RussiaPetrology, Natural diamonds
DS1860-0993
1897
Yeremeev, P.Jeremejew, P., Yeremeev, P.About the Diamonds from the Transvaal PremierObshch. Vses. Miner. Zap., Vol. 35, PP. 31-32. ALSO: ZEITSCHR. KRYST. (LEIPZIG), Vol. 3Africa, South Africa, TransvaalMineralogy, Alluvial Placers
DS1860-1089
1899
Yeremeev, P.Jeremejew, P., Yeremeev, P.Ueber Boortkrystalle aus TransvaalObshch. Vses. Miner. Zap., Vol. 36, PP. 35-36. ALSO: ZEITSCHR. KRYST. (LEIPZIG), Vol. 3Africa, South Africa, TransvaalBort, Mineralogy
DS1960-1232
1969
Yeremenko, G.K.Yeremenko, G.K., Polkanov, YU.A.Luminescence of Small Diamonds from Sandy Sediments of the Ukraine.Doklady Academy of Science USSR, Earth Science Section., Vol. 188, No. 4, PP. 149-151.RussiaKimberlite, Photoluminescence, Colour
DS1970-0175
1970
Yeremenko, G.K.Polkanov, YU.A., Yeremenko, G.K.Diamond Potential of the Southwest Margin of the Russian Platform.Kiev:, RussiaKimberlite, Kimberley
DS1984-0788
1984
Yeremenko, G.K.Yeremenko, G.K., Valter, A.A.Abyssal Inclusions of Proterozoic Camptonites of the Azov Region.Geolog. Zhurn., Vol. 44, No. 3, PP. 59-65.RussiaBlank
DS1990-1491
1990
Yeremenko, G.K.Valter, A.A., Kvasnitsa, V.N., Yeremenko, G.K.Structure, composition and optical properties of diamond paramorphs bygraphite.(Russian)Mineral. Zhurn., (Russian), Vol. 12, No. 3, pp. 3-16RussiaDiamond, Crystallography
DS1991-0446
1991
Yeremenko, G.K.Entin, A.R., Yeremenko, G.K., Tyan, O.K., Orlov, A.N.The francolite-groutite association: a new ore mineral type in the carbonatite rock associationDoklady Academy of Sciences, Earth Sci. Section, Vol. 307, No. 1-6, pp. 162-165RussiaCarbonatite, Alteration
DS1995-0992
1995
YeremeyevKononova, V.A., Bogatikov, O.A., Pervov, V.A., YeremeyevCentral Asian potassic magmatic rocks: geochemistry and formationconditions.Geochemistry International, Vol. 32, No. 2, pp. 23-42.Russia, AsiaAlkaline rocks, Geochemistry
DS1988-0066
1988
Yeremeyev, N.V.Bogatikov, O.A., Yeremeyev, N.V., Makhotkin, I.L., Kononova, V.A.Lamproites of the Aldan and central AsiaDoklady Academy of Science USSR, Earth Science Section, Vol. 290, No. 1-6, March pp. 154-157RussiaLamproite, Analyses
DS1988-0774
1988
Yeremeyev, N.V.Yeremeyev, N.V., Kononova, V.A., Makhotsin, I.L., et al.Native metals in lamproites of central AldanDokl. Acad. Sciences USSR Earth Science Section, Vol. 303, No. 6, pp. 167-171RussiaLamproites, Native metals
DS1993-1800
1993
Yeremeyv, N.V.Yeremeyv, N.V., Zhuravlev, .Z., Kononova, V.A., Pervov, V.A., Kramm, U.Source and age of the potassic rocks in the Ryabinov intrusion, centralAldan.Geochemistry International, Vol. 30, No. 6, pp. 105-112.Russia, AldanAlkaline rocks
DS1989-1128
1989
Yerkhov, V.A.Nikulin, V.I., Yerkhov, V.A., Pospeyev, V.I.Criteria for the prognosis of kimberlite fieldsInternational Geology Review, Vol. 31, No. 2, February pp. 186-195RussiaExploration, Kimberlite fields
DS1985-0236
1985
Yermolayev, V.V.Gladkikh, V.S., Lyapunov, S.M., Konova, M.I., Yermolayev, V.V.Geochemistry and Petrology of Volcanic Rocks in Maymecha Kotuy ProvinceGeochemistry International, Vol. 22, No. 1, pp. 157-167RussiaBlank
DS1984-0673
1984
Yermolayeva, L.A.Sinitsyn, A.V., Yermolayeva, L.A.The Problem of the Nature of Diamond Origins in Precambrian Placers.(russian)Zap. Vses. Min. Obsch.(Russian), Vol.113, No. 3, pp. 289-299RussiaDiamond, Placer
DS1985-0619
1985
Yermolayeva, L.A.Sinitsyn, A.V., Yermolayeva, L.A.The Problem of Precambrian Placer SourcesIn: International Symposium on metallogeny of the early Precambrian, Abtract volume in Eng. and Chinese pp. 33-34South Africa, India, BrazilPlacers
DS1975-0438
1976
Yermolenko, YU.P.Yermolenko, YU.P., Sobolev, V.K.Diamonds from Conglomerates of the Nadezhdin Suite Middle Devonian) of Northern Timan.Vyssh. Uchebn. Zaved. Izv. Geol. Razved., 1976, No. 12, PP. 159-161.RussiaBlank
DS1994-1968
1994
Yermolev, P.V.Yermolev, P.V.uranium-lead (U-Pb) (U-Pb) dating of lower crustal xenolithsGeochemistry International, Vol. 31, No. 5, pp. 70-77.MantleXenoliths, Geochronology
DS1989-1671
1989
Yeroshenko, V.A.Yeroshenko, V.A., Sharkov, Ye, .V.Thermodynamics of complex systems and their application to magmaticprocessesInternational Geology Review, Vol. 31, No. 10, October pp. 969-985RussiaMagma, Thermodynamics
DS202106-0937
2021
Yesares, L.Gomez-Arias, A., Yesares, L., Carabello, M.A., Maleke, M., Vermeulen, D., Nieto, J.M., van Heerden, E., Castillo, J.Environmental and geochemical characterization of alkaline mine wastes from Phalaborwa ( Palabora) complex, South Africa.Journal of Geochemical Exploration, Vol. 224, 106757, 13p. PdfAfrica, South Africadeposit - Palabora

Abstract: A detailed characterization of alkaline tailing ponds and waste rock dumps from Phalaborwa Igneous Complex (PIC) South Africa, has been accomplished. The study goes beyond the environmental characterization of mining wastes, offering the first insight towards the recycling of the wastes as alkaline reagent to neutralize acid industrial wastewater. To achieve these aims, tailings and waste rocks were characterized using a combination of conventional, novel and modified Acid Rock Drainage (ARD) prediction methodologies, as well as South African leachate tests, sequential extractions and pseudo-total digestions. The scarcity of Fe-sulphide minerals and the abundance of alkaline minerals indicated that PIC wastes are not ARD producers. The highest neutralization potential was found in the carbonatite rocks and East tailing samples (range between 289 and 801 kg CaCO3 eq/t). According to the National Environmental Management Waste Act (59/2008) of South Africa, tailing ponds and waste rock dumps from PIC classify as non-hazardous (Type 3 waste). The sequential extractions showed that the different fractions from most of the samples would mostly release sulphate and non-toxic elements, such as Ca, Mg, Na and K, which might be a concern if leached in high concentration. In addition, relatively high concentrations of radionuclides, such as U and Th (average of 6.7 and 36.3 mg/kg, respectively) are present in the non-labile fraction of PIC wastes, while the leachable concentrations were always below 0.006 mg/L. Among PIC wastes, East tailing would be the best option as alkaline reagent to neutralize acid wastewater because of its high neutralization potential and non-harmful leachate composition. In general, this study exposes the shortcomings in mine waste characterization, particularly for alkaline mine wastes, and introduces the assessment of potential revalorization as a novel practice in mine waste characterization that, if extended as a regular practice, would facilitate a circular economy approach to the mining industry with its consequent economic and environmental benefits.
DS1984-0789
1984
Yeske, L.A.Yeske, L.A.The Application of Hydrographic Survey Technology to the Mapping of In shore Diamonds Mines.Mar. Tech. Sci. Journal, Vol. 18, No. 4, PP. 23-27.VenezuelaBlank
DS1985-0750
1985
Yeskova, YE.M.Yefimov, A.F., Yeskova, YE.M., Lebedeva, S.I., Levin, V. YA.Type Compositions of Accessory Pyrochlore in a Ural Alkali ComplexGeochemistry International, Vol. 22, No. 1, pp. 68-75RussiaAlkaline Rocks
DS1995-1595
1995
Yesou, H.Rolet, J., Yesou, H., Besnus, Y.Satellite image analysis of circular anomalies and fracturing networks In the Amorican MassifMapping Sciences and Remote Sensing, Vol. 32, No. 1, Jan-Mar pp. 21-43FranceRemote Sensing, Structure
DS201412-1008
2014
Yeston, J.Yeston, J.The power of a pair of perovskites.Science, Vol. 345, 6204, Sept. 26, p. 1593.TechnologySolar cells
DS200712-0447
2007
Yeun, D.A.Hofmeister, A.M., Yeun, D.A.Critical phenomena in thermal conductivity: implications for lower mantle dynamics.Journal of Geodynamics, Vol. 44, 3-5, pp. 186-199.MantleGeothermometry
DS201607-1305
2016
Yeung, L.Lee, C-T. A., Yeung, L., McKenzie, N.R., Yokoyama, Y., Ozaki, K.Two step rise of atmospheric oxygen linked to the growth of continents. (carbon)Nature Geoscience, Vol. 9, 6, pp. 417-424.MantleCarbon

Abstract: Earth owes its oxygenated atmosphere to its unique claim on life, but how the atmosphere evolved from an initially oxygen-free state remains unresolved. The rise of atmospheric oxygen occurred in two stages: approximately 2.5 to 2.0 billion years ago during the Great Oxidation Event and roughly 2 billion years later during the Neoproterozoic Oxygenation Event. We propose that the formation of continents about 2.7 to 2.5 billion years ago, perhaps due to the initiation of plate tectonics, may have led to oxygenation by the following mechanisms. In the first stage, the change in composition of Earth's crust from iron- and magnesium-rich mafic rocks to feldspar- and quartz-rich felsic rocks could have caused a decrease in the oxidative efficiency of the Earth's surface, allowing atmospheric O2 to rise. Over the next billion years, as carbon steadily accumulated on the continents, metamorphic and magmatic reactions within this growing continental carbon reservoir facilitated a gradual increase in the total long-term input of CO2 to the ocean -atmosphere system. Given that O2 is produced during organic carbon burial, the increased CO2 input may have triggered a second rise in O2. A two-step rise in atmospheric O2 may therefore be a natural consequence of plate tectonics, continent formation and the growth of a crustal carbon reservoir.
DS1981-0438
1981
Yevdokimov, A.N.Yevdokimov, A.N., Bagdasarov, E.A.The Associations and Sequential Formations of Oxides of Chromium, Titanium, and Iron in Kimberlites and Porphyritic Picrites in the Kuonamka Region.Zapiski Vses. Mineral. Obsch., Vol. 110, No. 2, PP. 204-212.RussiaBlank
DS1982-0649
1982
Yevdokimov, A.N.Yevdokimov, A.N., Bagdasarov, E.A.Microcrystalline Ilmenite in Relation to Kimberlite Mass Of kuonam Region, Yakutia.Zap. Vses. Mineral. Obshch, Vol. 111, No. 5, PP. 570-581.RussiaMineralogy
DS1982-0650
1982
Yevdokimov, A.N.Yevdokimov, A.N., Bagdasarov, E.A.Compositions and Typical Chemical Features of Pyrope Garnets from Kimberlites in the Middle and Lower Kuonam Fields in Yakutia.International Geology Review, Vol. 24, No. 5, PP. 548-558.Russia, YakutiaGeochemistry, Mineralogy, Classification, Garnet
DS1982-0651
1982
Yevdokimov, A.N.Yevdokimov, A.N., Zilbershkaya, A.K., Khotina, M.I., Shishlov.Anisotropy of Pyrope and Almandine of Kimberlites in the Lower and Middle Kuonam, Yakutia.Zap. Vses. Mineral Obshch., Vol. 111, No. 2, PP. 247-250.RussiaBlank
DS1985-0756
1985
Yevdokimov, A.N.Yevdokimov, A.N., Bagdasarov, E.A.Ilmenites of kimberlites and associated placers in northeastern SiberianPlatform*(in Russian)Zapisk. Vses. Mineral. Obshch., (Russian), Vol.114, No. 2, pp. 201-212RussiaPetrology, Analyses
DS201012-0874
2010
Yevzerov, V.Ya.Yevzerov, V.Ya., Nikolaeva, S.B.Reconstruction of the surface of the Late Vaidal ice sheet in the area of Khibini and Lovozerskii mountain ranges on the Kola Peninsula.Doklady Earth Sciences, Vol. 430, 1, pp. 101-103.Russia, Kola PeninsulaGeomorphology
DS1986-0886
1986
Yezerskiy, V.A.Yezerskiy, V.A.high pressure polymorphs produced by shock transformation of coalsInternational Geology Review, Vol. 28, No. 2, pp. 221-228RussiaCarbonado
DS1988-0775
1988
Yfantis, E.A.Yfantis, E.A., Flatman, G.T.On sampling nonstationary spatial autocorrelated dataComputers and Geosciences, Vol. 14, No. 5, pp. 667-686. Database # 17381GlobalComputers, Program
DS201605-0863
2016
Y-GMa, L., Jiang, S-Y., Hofmann, A.W., Xu, Y-G, Dai, B-Z., Hou, M-L.Rapid lithospheric thinning of North Chin a craton: new evidence from Cretaceous mafic dikes in the Jiaodong Peninsula.Chemical Geology, Vol. 432, pp. 1-15.ChinaDikes

Abstract: The North China Craton is a classic case for the destruction of an ancient craton, in that it records the loss of more than 100 km of ancient refractory lithospheric mantle during the late Mesozoic and early Cenozoic. However, the mechanisms for this lithospheric thinning remain controversial in large part due to the lack of any systematic investigations of the Mesozoic asthenospheric mantle via its derived mafic rocks, which are key to understand the thinning processes. In this paper, we present detailed zircon U-Pb geochronology, elemental geochemistry, and Sr-Nd-Hf isotopic data for lamprophyres and diabase-porphyries of the Jiaodong Peninsula, in the eastern North China Craton in order to place constraints on models for lithospheric thinning. Our results show that the lamprophyres and diabase-porphyries are derived from the convective asthenospheric mantle via different degrees of partial melting, and that this mantle source was previously modified by carbonatitic liquids. Zircon LA-ICP-MS U-Pb dating suggests an emplacement age for these rocks of 123-121 Ma, the earliest evidence for asthenospherically-derived melts in the Jiaodong Peninsula so far. This emplacement age indicates that the thickness of the lithosphere in the Jiaodong Peninsula was relatively thin at that time. Co-occurrence of the asthenospheric and lithospheric mantle-derived mafic rocks as well as high-Mg adakites record a rapid transition from lithospheric to asthenospheric mantle sources, indicating that the lithosphere beneath the Jiaodong Peninsula was rapidly detached just prior to ca. 120 Ma. Lithospheric thinning of the North China Craton may have been initiated from the Jiaodong Peninsula and Bohai Sea and then propagated towards the interior of the craton.
DS201112-0567
2011
Y-HLan, T-G., Fan, H-R., Santosh, M., Hu, F-F., Yang, Y-H, Liu, Y.Geochemistry and Sr Nd Pb Hf isotopes of the Mesozoic Dadian alkaline intrusive complex in the Sulu orogenic belt, eastern China: implications for crust mantle interaction.Chemical Geology, Vol. 285, 1-4, pp. 97-114.ChinaAlkalic
DS1986-0563
1986
YiMerezhko, YiBoundaries of diamond metastable zone formation in the graphite stability range in the metal carbon system (Technical Note).(Russian)Zhurn. Fiz. Khim., (Russian), Vol. 60, No. 5, pp. 1250-1251RussiaDiamond morphology
DS200412-2085
2004
YiWang, Yi, Wen, L.Mapping the geometry and geographic distribution of a very low velocity province at the base of the Earth's mantle.Journal of Geophysical Research, Vol. 109, B10, B10305 dx.doi.org/10.1029/2004 JB002674MantleGeophysics - seismics, stratigraphy
DS200812-1241
2008
YiWang, Yi, Wen, L., Weidner, D.Upper mantle SH and P velocity structures and compositional model beneath southern Africa.Earth and Planetary Science Letters, Vol. 267, 3-4, pp.596-608.Africa, South AfricaGeophysics - seismics
DS201412-0792
2014
Yi, J.Selway, K., Yi, J., Karato, S-I.Water content of the Tanzanian lithosphere from magnetotelluric data: implications for cratonic growth and stability.Earth and Planetary Science Letters, Vol. 388, pp. 175-186.Africa, TanzaniaGeophysics
DS200612-0603
2006
Yi, L.Hou, Z., Tian, S., Yuan, Z., Xie, Y., Yin, S., Yi, L., Fei, H., Yang, Z.The Himalayan collision zone carbonatites in western Sichuan, SW China: petrogenesis, mantle source and tectonic implication.Earth and Planetary Science Letters, in pressAsia, ChinaCarbonatite
DS200912-0313
2009
Yi, L.Hou, Z., Tian, S., Xie, Y., Yang, Z., Yuan, Z., Yin, S., Yi, L., Fei, H., Zou, T., Bai, G., Li, X.The Himalayan Mianning Dechang REE belt associated with carbonatite alkaline complexes eastern Indo Asian collision zone, SW China.Ore Geology Reviews, Vol. 36, 1-3, pp. 65-89.ChinaCarbonatite
DS1992-1705
1992
Yiang RuiyangXu Weniang, Chi Xiaoguo, Yuan Chao, Yiang RuiyangThe upper mantle and lower crust in the central North Chin a PlatformInternational Symposium Cenozoic Volcanic Rocks Deep seated xenoliths China and its, Abstracts pp. 98-101ChinaMantle, Xenoliths
DS1996-1526
1996
YicanWen, Su, Shutong, Xu, Laili, J., Yican, LiuCoesite from quartz jadeitite in the Dabie Mountains, eastern ChinaMineralogical Magazine, Vol. 60, pp. 659-662.ChinaCoesite
DS1996-1525
1996
Yican, L.Wen, S., Shutong, X., Yican, L.Coesite from quartz jadeiite in the Dabie Mountains, eastern ChinaMineralogical Magazine, Vol. 60, No. 4, Aug. 1, pp. 659-662.ChinaMineralogy, Coesite
DS1991-1434
1991
Yielding, G.Roberts, A.M., Yielding, G., Freeman, B.The geometry of normal faultsGeological Society of London Special Publication, No. 56, 275pBaltic States, North Sea, Alps, Germany, Greece, EgyptStructure, fault, geophysics, seismics, Tectonics
DS1991-1435
1991
Yielding, G.Roberts, A.M., Yielding, G., Freeman, B.Geometry of normal faultsGeological Society of London Special Publ, No. 56, 264p. ISBN 0-903317-59-1 $ 110.25 United StatesBookEurope, Structure -normal faults
DS1991-1826
1991
Yielding, G.Walsh, J., Watterson, J., Yielding, G.The importance of small scale faulting in regional extensionNature, Vol. 351, No. 6325, May 30, p. 391-394GlobalStructure, Faulting - small scale
DS1991-1855
1991
Yielding, G.White, N., Yielding, G.Calculating normal fault geometries at depth: theory and examplesThe geometry of normal faults, editors Roberts, A.M., Yielding, G., No. 56, pp. 251-260GlobalStructure -faults, Fault geometry
DS200412-1113
2004
Yifei, D.Lei, Z., Jinhua, H., Yifei, D., Yulong, L.Assortment of deep mantle fluids and their products in kimberlites from China.Acta Geologica Sinica, Vol. 78, 1, pp. 118-120.ChinaGeochemistry, mineral chemistry
DS1995-2104
1995
YikangYikang, LiuInvestment possibilities and mineral resources exploration in ChinaProspectors and Developers Association of Canada (PDAC) Reprint, 16pChinaMineral resources, Economics
DS202205-0703
2021
Yildirim, B.Mansoor, M., Mansoor, M., Mansoor, M., Aksoy, A., Seyhan, S.N., Yildirim, B., Tahiri, A., Solak, N., Kazmanli, K., Er, Z., Czelej, K., Urgen, M.Ab-nitro calculation of point defect equilibria during heat treatment: nitrogen, hydrogen, and silicon doped diamond.Researchgate preprint Istanbul Technical University , 18p. PdfGlobaldiamond morphology

Abstract: Point defects are responsible for a wide range of optoelectronic properties in materials, making it crucial to engineer their concentrations for novel materials design. However, considering the plethora of defects in co-doped semiconducting and dielectric materials and the dependence of defect formation energies on heat treatment parameters, process design based on an experimental trial and error approach is not an efficient strategy. This makes it necessary to explore computational pathways for predicting defect equilibria during heat treatments. The accumulated experimental knowledge on defect transformations in diamond is unparalleled. Therefore, diamond is an excellent material for benchmarking computational approaches. By considering nitrogen, hydrogen, and silicon doped diamond as a model system, we have investigated the pressure dependence of defect formation energies and calculated the defect equilibria during heat treatment of diamond through ab-initio calculations. We have plotted monolithic-Kröger-Vink diagrams for various defects, representing defect concentrations based on process parameters, such as temperature and partial pressure of gases used during heat treatments of diamond. The method demonstrated predicts the majority of experimental data, such as nitrogen aggregation path leading towards the formation of the B center, annealing of the B, H3, N3, and NVHx centers at ultra high temperatures, the thermal stability of the SiV center, and temperature dependence of NV concentration. We demonstrate the possibility of designing heat treatments for a wide range of semiconducting and dielectric materials by using a relatively inexpensive yet robust first principles approach, significantly accelerating defect engineering and high-throughput novel materials design.
DS201012-0875
2010
Yilmaz, K.Yilmaz, K.Orogin of anorogenic lamproite like potassic lavas from the Denizli region in western Anatolia extensional province, Turkey.Mineralogy and Petrology, Vol. 99, 3, pp. 219-239.Europe, TurkeyLamproite
DS1990-1613
1990
Yilmaz, Y.Yilmaz, Y.Allochthonous terranes in the Tethyan middle East: Anatolia and surroundingregions.Phil. Transactions Royal Society. Lond., Vol. A331, pp. 611-24.TurkeyTectonics - orogen
DS1993-1801
1993
Yin, A.Yin, A., Oertel, G.Kinematics and strain distribution of a thrust related fold system in the Lewis Plate, northwestern Montana.Journal of Structural Geology, Vol. 15, No. 6, pp. 707-19.MontanaTectonics, structure
DS1996-1579
1996
Yin, A.Yin, A., Harrison, T.M.The tectonic evolution of AsiaCambridge University of Press, 650p. approx. $ 260.00 United StatesGlobalBook - table of contents, Tectonic evolution
DS200712-1205
2007
Yin, A.Yin, A., Manning, C.E., Lovera, O., Menold, C.A., Chen, X., Gehrels, G.Early Paleozoic tectonic and thermomechanical evolution of ultrahigh pressure (UHP) metamorphic rocks in the northern Tibetan Plateau, northwest China.International Geology Review, Vol. 49, 8, pp. 681-716.ChinaUHP
DS202003-0373
2020
Yin, A.Yin, A., Brandl, G., Kroner, A.Plate tectonics processes at ca 2.0 Ga: evidence from >600 km of plate convergence. Limpopo beltGeology, Vol. 48, pp. 103-107.Africa, South Africatectonics

Abstract: We addressed when plate-tectonic processes first started on Earth by examining the ca. 2.0 Ga Limpopo orogenic belt in southern Africa. We show through palinspastic reconstruction that the Limpopo orogen originated from >600 km of west-directed thrusting, and the thrust sheet was subsequently folded by north-south compression. The common 2.7-2.6 Ga felsic plutons in the Limpopo thrust sheet and the absence of an arc immediately predating the 2.0 Ga Limpopo thrusting require the Limpopo belt to be an intracontinental structure. The similar duration (?40 m.y.), slip magnitude (>600 km), slip rate (>15 mm/yr), tectonic setting (intracontinental), and widespread anatexis to those of the Himalayan orogen lead us to propose the Limpopo belt to have developed by continent-continent collision. Specifically, the combined Zimbabwe-Kaapvaal craton (ZKC, named in this study) in the west (present coordinates) was subducting eastward below an outboard craton (OC), which carried an arc equivalent to the Gangdese batholith in southern Tibet prior to the India-Asia collision. The ZKC-OC collision at ca. 2.0 Ga triggered a westward jump in the plate convergence boundary, from the initial suture zone to the Limpopo thrust within the ZKC. Subsequent thrusting accommodated >600 km of plate convergence, possibly driven by ridge push from the west side of the ZKC. As intracontinental plate convergence is a key modern plate-tectonic process, the development of the Limpopo belt implies that the operation of plate tectonics, at least at a local scale, was ongoing by ca. 2.0 Ga on Earth.
DS202111-1794
2021
Yin, B.Zuo, R., Wang, J., Yin, B.Visualization and interpretation of geochemical exploration data using GIS and machine learning methods. *** Not specific to diamondApplied Geochemistry, Vol. 134, 105111, 10p. PdfGlobalgeochemistry

Abstract: Geochemical exploration has provided significant clues for mineral exploration and has helped discover many mineral deposits. Although various methods, including classic statistics, multivariate statistics, geostatistics, fractal/multifractal models, and machine learning algorithms, have been successfully employed to process geochemical exploration data, efficient interpretation and visualization of geochemical exploration data in support of the discovery of mineral deposits remain challenging. In this study, a workflow for intelligent interpretation and visualization of geochemical exploration data, defined as processing geochemical survey data with support of a geographical information system (GIS) and machine learning algorithms, was proposed. The effectiveness of the intelligent interpretation and visualization of geochemical exploration data supported by GIS and machine learning algorithms was demonstrated using a case study of processing a regional-scale geochemical survey dataset collected from Sichuan Province, China. Future research should add more advanced mathematical and statistical models, such as deep learning algorithms, into GIS to support the intelligent interpretation and visualization of geochemical exploration data.
DS202111-1795
2021
Yin, B.Zuo, R., Wang, J., Yin, B.The processing methods of geochemical exploration data: past, present, and future. *** not specific to diamondApplied Geochemistry, Vol. 132, 105072 9p. PdfGlobalreview

Abstract: Geochemical exploration data is popular in mineral exploration in that it plays a notable role in discovering unknown mineral deposits. In this study, we review the state-of-the-art popular methods for processing geochemical exploration data and for identifying geochemical anomalies associated with mineralization. The distribution laws of geochemical elements concentrations, including normal, log-normal, power-law, and multimodal and complex distributions, have been extensively studied over the past several decades. Accordingly, methods for processing geochemical exploration data have shifted from classic statistics, multivariate statistics, geostatistics, to fractal/multifractal models and machine learning algorithms. Geochemical exploration data, as compositional data, suffer from the closure problem. We need first to open them using logratio transformation. In the future, deep learning algorithms will become a popular technique for mining geochemical exploration data and for extracting targets associated with mineralization in mineral exploration.
DS202202-0226
2021
Yin, J.N.Yin, J.N., Song, X.A review of major rare earth element and yttrium deposits in China.Australian Journal of Earth Sciences, Vol.1, pp. 1-25. pdfChinaREE

Abstract: Rare earth element and yttrium (REY) deposits are important strategic resources widely used in high-tech applications, such as solar cells and wind turbines. This paper summarises the temporal-spatial characteristics and genesis of REY deposits in China classified as alkaline carbonatite, ion-adsorption, placer, sedimentary metamorphism, marine sedimentary phosphorite and coal-hosted REY types. This study focuses on alkaline carbonatite and ion-adsorption deposits, because of their importance in terms of both exploitation and global reserves. The general characteristics, genesis, and enrichment of these REY deposit types are summarised, and eight districts have been identified as having prospectivity for REY, based on geological and geochemical data. An overview of these districts is presented, together with a detailed investigation of four important districts in terms of geological settings, mineralisation, regional deposit models and metallogenic prospect. KEY POINTS: 1) REY deposits in China can be classified as alkaline carbonatite, ion-adsorption, placer, sedimentary metamorphism and marine sedimentary phosphorite and coal-hosted REY types. 2) Ion-adsorption REY in the weathering profile of granitic rocks is strongly controlled by the resistance to weathering, climate, topography and layers of weathering crust. 3) Carbonatite and alkaline rocks are major hosts for REYs and commonly have high concentrations of REY-bearing accessory minerals. 4) Eight districts have been identified as having prospectivity for REY in China.
DS201911-2523
2019
Yin, P.Gao, Y., Yin, P.Determination of crystallite size of nanodiamond by raman spectroscopy.Diamond & Related Materials, Vol. 99, 107524Globalnanodiamond

Abstract: Although the phonon confinement model (PCM) was claimed to be successfully used to accurately calculate the size of larger Si nanocrystals, quantitative size characterization by Raman spectra still remains a challenge in the case of nanodiamonds due to its complexity. Here, we find that a local-mode model of Raman spectra developed recently can be employed to determine the bond number of the ordered diamond core in nanodiamonds, and then furtherly determine the size of nanodiamonds. The Raman lines of nanodiamonds of 3.0?nm, 2.0?nm, 2.2?nm, 3.3?nm, 3.7?nm 4.42?nm and 6.3?nm are calculated. Results are in good agreement with the measured Raman spectra. It not only provides a new approach to predict the size of nanodiamonds accurately by Raman spectra, but also helps to clarify issues in Raman spectra of nanodiamond and other carbon nanomaterials.
DS1998-0678
1998
Yin, Q.Jacobsen, S.B., Yin, Q.Models for the accretion and early differentiation of the EarthMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 694-5.MantleAccretion
DS200512-0927
2005
Yin, Q.Z.Saha, A., Basu, A.R., Jacobsen, S.B., Poreda, R.J., Yin, Q.Z., Yogodzinski, G.M.Slab devolatization and Os and Pb mobility in the mantle wedge of the Kamchatka arc.Earth and Planetary Science Letters, Advanced in press,Russia, KamchatkaGeochronology, slab
DS201112-0011
2011
Yin, Q-Z.Albaraede, F., Ballhaus, C., Lee, C.T.A., Yin, Q-Z., Blichert-Toft, J.The great volatile delivery to Earth.Goldschmidt Conference 2011, abstract p.420.MantleGeochronology - Pb
DS201312-0202
2013
Yin, Q-Z.DeBaille, V., O'Neill, C., Brandon, A.D., Haenecour, P., Yin, Q-Z., Mattielli, N., Trieman, A.H.Stagnant lid tectonics in early Earth revealed bu 142 Nd variations in late Archean rocks.Earth and Planetary Science Letters, Vol. 373, pp. 83-92.MantleConvection
DS202104-0616
2021
Yin, R.Wu, B., Hu, Y-Q., Bonnetti, C., Xu, C., Wang, R-C., Zhang, Z-S., Li, Z-Y., Yin, R.Hydrothermal alteration of pyrochlore group minerals from the Miaoya carbonatite complex, central China and its implications for Nb mineralization.Ore Geology Reviews, Vol. 132, 1040459, 16p. PdfChinadeposit - Miaoya

Abstract: Carbonatite represents a major host rock for niobium (Nb) resources worldwide. Both magmatic and post-magmatic metasomatic processes are crucial for Nb mineralization in carbonatites. However, the roles of these metasomatic processes are difficult to be evaluated due to their multiple origins and complexity of the physico-chemical conditions. In this study, we present detailed mineralogical investigations of pyrochlore group minerals and chemical U-Th-Pb geochronology of uraninite within the Miaoya carbonatite complex, aiming to better characterize the role of post-magmatic metasomatic events. The Miaoya complex (ca. 420-440?Ma) hosts the second largest carbonatite-related Nb deposit in China, mainly in the form of pyrochlore group minerals, ferrocolumbite and Nb-bearing rutile. Primary pyrochlore group minerals evolved from pyrochlore to uranpyrochlore, and ultimately reaching the betafite end-member during the magmatic stage. They have then experienced an episode of metasomatic events at 235.4?±?4.1?Ma, as determined by U-Th-Pb chemical ages of secondary uraninite. Fluids activity for uranpyrochlore alteration was concomitant with the hydrothermal reworking of REE mineralization, which was probably related to tectono-thermal events that occurred during the Triassic closure of the ancient Mianlue Ocean. During this process, hydration and decomposition of uranpyrochlore were characterized by the leaching of Na, Ca and F from its structure, the incorporation of Fe, Si, Sr and Ba from the fluids, and the final in situ replacement by secondary ferrocolumbite, uraninite and Nb-bearing rutile. In addition, parts of Nb and U liberated from uranpyrochlore by metamictization were then transported over distances of several hundreds of microns in relatively reducing (Fe, Si, S, CO2)-bearing fluids under high temperature, and were ultimately re-precipitated in amorphous Fe-Si-U-Nb-bearing oxide veins and poorly crystallized Nb-Ti-Ca-Fe-rich oxides. The relatively weak fluids activity failed to efficiently promote the Nb re-enrichment.
DS200612-0603
2006
Yin, S.Hou, Z., Tian, S., Yuan, Z., Xie, Y., Yin, S., Yi, L., Fei, H., Yang, Z.The Himalayan collision zone carbonatites in western Sichuan, SW China: petrogenesis, mantle source and tectonic implication.Earth and Planetary Science Letters, in pressAsia, ChinaCarbonatite
DS200912-0313
2009
Yin, S.Hou, Z., Tian, S., Xie, Y., Yang, Z., Yuan, Z., Yin, S., Yi, L., Fei, H., Zou, T., Bai, G., Li, X.The Himalayan Mianning Dechang REE belt associated with carbonatite alkaline complexes eastern Indo Asian collision zone, SW China.Ore Geology Reviews, Vol. 36, 1-3, pp. 65-89.ChinaCarbonatite
DS201508-0382
2015
Yin, S.Xie, Y., Li, Y., Hou, Z., Cooke, D.R., Danyushevsky, L., Dominy, S.C., Yin, S.A model for carbonatite hosted REE mineralization - the Mianning-Dechang REE belt, western Sichuan Province, China.Ore Geology Reviews, Vol. 70, pp. 595-612.ChinaCarbonatite
DS200812-0674
2008
Yin, X.Liu, D., Wilde, S.A, Wan, Y., Wu, J., Zhou, H., Dong, C., Yin, X.New U Pb and Hf isotopic dat a confirm Anshan as the oldest preserved segment of the North Chin a Craton.American Journal of Science, Vol. 308, 3, pp. 200-231.ChinaGeochronology
DS201702-0257
2017
Yin, Z.Yin, Z., Jiang, C., Chen, M., Lu, F., Quanli, C.Inclusions of a-quartz, albite and olivine in a mantle diamond.Gondwana Research, in press available, 29p.ChinaDeposit - Shengli no. 1

Abstract: Mineral inclusions in diamonds have been used to track potential information on the Earth's deep mantle. Here we report results from a detailed study on the mineral inclusions in a ca. 0.28 ct diamond from the Shengli No. 1 kimberlite in Mengyin County, Shandong Province, eastern China. Our study reveals the presence of ?-quartz, albite and olivine in the diamond. At an inferred depth of ca. 165 km for the diamond crystallization, the inclusions of ?-quartz and albite suggest the possible involvement of deep subducted crustal material, traces of which were captured during the diamond growth and magma migration.
DS202107-1140
2021
YingSun, Y., Teng, F-Z., Pang, K-N., Ying, J-F, Kuehner, S.Multistage mantle metasomatism deciphered by Mg-Sr-Nd-Pb isotopes in the Leucite Hills lamproite.Contributions to Mineralogy and Petrology, Vol. 176, 45, 10.1007/s00410-021-01801-9 pdfUnited States, Wyomingdeposit - Leucite Hills

Abstract: Cratonic lamproites bear extreme Sr?Nd?Pb isotopic compositions widely known as enriched mantle I (EMI), yet the origin of the EMI reservoir remains controversial. Here, we explore this issue by examining Mg?Sr?Nd?Pb isotopic compositions of lamproites from Leucite Hills, Wyoming, USA. The ?26Mg values vary from the range of the normal mantle to lower values (? 0.43 to ? 0.18 ‰), correlating with indices of the degree of carbonate metasomatism, an observation that can be best explained through mantle metasomatism by subducted carbonate-bearing sediments. With increasing extent of carbonate metasomatism, these samples display less extreme EMI Sr?Nd?Pb isotopic signatures, arguing for at least two metasomatic events that occurred in their mantle sources. The early metasomatic event associated with subducted continent-derived siliciclastic sediments led to the formation of the EMI Sr?Nd?Pb isotopic signatures while the recent carbonate metasomatism produced the light Mg isotopic signature but diluted the EMI Sr?Nd?Pb isotopic signatures. Our study indicates that a combination of Mg and Sr?Nd?Pb isotopes could be an effective tool in deciphering multiple-stage metasomatic events in mantle sources and places new constraints on the generation of enriched mantle reservoirs.
DS200412-2182
2004
Ying, J.Ying, J., Zhou, X., Zhang, H.Geochemical and isotopic investigation of the Laiwu-Zibo carbonatites from western Shandong Province, Chin a and implications forLithos, Vol. 75, 3-4, pp. 413-426.China, ShandongCarbonatite
DS200612-1570
2006
Ying, J.Ying, J., Zhang, H., Kita, N., Morishita, Y., Shimoda, G.Nature and evolution of Late Cretaceous lithospheric mantle beneath the eastern north Chin a craton: constraints from petrology and geochemistry from JunanEarth and Planetary Science Letters, in pressAsia, China, ShandongPeridotitic xenoliths
DS201012-0764
2010
Ying, J.Su, B., Zhang, H., Tang, Y., Chisonga, B., Qin, K., Ying, J., Sakyi, P.A.Geochemical syntheses among the cratonic, off-cratonic and orogenic garnet peridotites and their tectonic implications.International Journal of Earth Sciences, In press available, 21p.MantlePeridotite, geochemistry
DS201112-1015
2011
Ying, J.Su, B., Zhang, H., Tang, Y., Chisonga, B., On, K., Ying, J., Sakyi, P.A.Geochemical syntheses among the cratonic, off cratonic and orogenic garnet peridotites and their tectonic implications.International Journal of Earth Sciences, Vol. 100, 4, pp.695-715.MantleCraton, kimberlites mentioned
DS201412-0899
2014
Ying, J.Sun, Y., Ying, J., Zhou, X., Chu, Z., Su, B.Geochemistry of ultrapotassic volcanic rocks in Xiaogulihe NE China: implications for the role of ancient suducted sediments.Lithos, Vol. 208-209, pp. 53.66.ChinaSubduction
DS200512-1241
2005
Ying, J.F.Zhang, H.F., Sun, M., Zhou, X.H., Ying, J.F.Geochemical constraints on the origin of Mesozoic alkaline intrusive complexes from the North Chin a Craton and tectonic implications.Lithos, Vol. 81, 1-4, pp. 297-317.ChinaGeochemistry
DS200712-1067
2007
Ying, J-F.Tang, Y-J., Zhang, H-F., Nakamura, E., Moriguti, T., Kobayashi, K., Ying, J-F.Lithium isotopic systematics of peridotite xenoliths from Hannuoba, North Chin a Craton: implications for melt rock interaction in considerably thinned mantle lithospheric mantle.Geochimica et Cosmochimica Acta, Vol. 71, 17, Sept. 1, pp. 4327-4341.ChinaGeochronology
DS200812-1136
2008
Ying, J-F.Su, B-X., Zhang, H-F., Ying, J-F., Xiao, Y., Zhao, X-M.Nature and processes of the lithospheric mantle beneath the western Qinling: evidence from deformed peridotitic xenoliths in Cenozoic kamafugite from Haoiti, Gansu ProJournal of Asian Earth Sciences, Vol. 34, 3, pp. 258-274.ChinaKamafugite
DS200912-0738
2009
Ying, J-F.Su, B-X., Zhang, H-F., Ying, J-F., Xiao, Y., Zhao, X-M.Nature and processes of the lithospheric mantle beneath the western Qinling: evidence from deformed peridotitic xenoliths in Cenozoic kamafugite from Haoti Province.Journal of Asian Earth Sciences, Vol. 34, pp. 258-274.ChinaKamafugite
DS201012-0765
2010
Ying, J-F.Su, B-X., Zhang, H-F., Sakyi, P.A., Yang, Y-H., Ying, J-F., Tang, Y-J., Qin, K-Z., Xiao, Y., Zhao, Mao, MaThe origin of spongy texture in minerals of mantle xenoliths from the western Qinling, central China.Contributions to Mineralogy and Petrology, in press available, 18p.ChinaXenoliths
DS201012-0766
2010
Ying, J-F.Su, B-X., Zhang, H-F., Sakyi, P.A., Ying, J-F., Tang, Y-J., Yang, Y-H., Qin, K-Z., Xiao, Y., Zhao, X-M.Compositionally stratified lithosphere and carbonatite metasomatism recorded in mantle xenoliths from the Western Qinling (Central China).Lithos, Vol. 116, pp. 111-128.ChinaCarbonatite
DS201012-0888
2010
Ying, J-F.Zhang, H-F., Nakamura, E., Kobayashi, K., Ying, J-F., Tang, Y-J.Recycled crustal melt injection into lithospheric mantle: implication from cumulative composite and pyroxenite xenoliths.International Journal of Earth Sciences, Vol. 99, pp. 1167-1186.ChinaNorth China craton
DS201112-1027
2011
Ying, J-F.Tang, Y-J., Zhang, H-F., Nakamura, E., Ying, J-F.Multistage melt fluid peridotite interactions in the refertilized lithospheric mantle beneath the North Chin a craton: constrains from the Li Sr Nd isotopicContributions to Mineralogy and Petrology, Vol. 161, 6, pp.MantlePeridotitic xenoliths
DS201212-0710
2012
Ying, J-F.Su, B-X., Ying, J-F., Liu, P-P.Extremely high Li and low delta 7Li signatures in the lithospheric mantle.Chemical Geology, Vol. 292-293, pp. 149-157.MantleEclogite
DS201212-0716
2013
Ying, J-F.Tang, Y-L., Zhang, H-F., Ying, J-F., Su, B-X., Chu, Z.Y., Xiao, Y., Zhao, X-M.Highly heterogeneous lithospheric mantle beneath the Central Zone of the North Chin a Craton evolved from Archean mantle through diverse melt refertilization.Gondwana Research, Vol. 23, 1, pp. 130-140.ChinaMelting
DS201212-0812
2012
Ying, J-F.Zhang, H-F., Yang,Y-H., Santosh, M., Zhao, X-M., Ying, J-F., Xiao, Y.Evolution of the Archean and Paleoproterozoic lower crust beneath the Trans-North Chin a Orogen and the western block of the north Chin a craton.Gondwana Research, Vol. 22, 1, pp. 73-85.ChinaGeochronology, tectonics, cratons
DS201212-0813
2013
Ying, J-F.Zhang, H-F.,Zhu, R-X., Ying, J-F., Hu, Y.Episodic Wide spread magma underplating beneath the North Chin a craton in the Phanerozoic: implications for craton destruction.Gondwana Research, Vol. 23, 1, pp. 95-107.ChinaGeothermometry
DS201312-0900
2013
Ying, J-F.Tang, J-L., Zhang, H-F., Ying, J-F., Su, B-X.Wide spread fertilization of cratonic and circum-cratonic lithospheric mantle.Earth Science Reviews, Vol. pp. 45-68.MantleSubduction
DS1998-0417
1998
Ying, W.Fengziantq, L., Ying, W., Jianping, Z.Geochemical characteristics and emplacement ages of the Menghyinkimberlites, Shandong Province.International Geology Review, Vol. 40, No. 11, Nov. pp. 998-1007.China, ShandongGeochemistry, genesis, Deposit - Menghyin
DS2000-0290
2000
Ying, W.Fengxiang, L., Ying, W., Meihuam C., Jianping, Z.Geochemical characteristics and emplacement ages of the Mengyin kimberlites,Shandong Province.Snyder, Neal, Ernst, Plan. Petrology and Geochemistry, pp. 74-82.China, ShandongGeochemistry, Deposit - Mengyin
DS201709-2077
2017
Ying, Y.Ying, Y., Chen, W., Lu, J., Jiang, S-Y., Yang, Y.In situ U-Th-Pb ages of the Miaoya carbonatite complex in the South Qinling orogenic belt, central China.Lithos, in press available, 57p.Chinacarbonatite - Miaoya

Abstract: The Miaoya carbonatite complex in the South Qinling orogenic belt hosts one of the largest rare earth element (REE)-Nb deposits in China that is composed of carbonatite and syenite. The emplacement age of the complex and the geochronological relationship between the carbonatite and syenite have long been debated. In this study, in situ U-Th-Pb ages have been obtained for the constituent minerals zircon, monazite and columbite from carbonatite and syenite of the Miaoya complex, together with their chemical and isotopic compositions. In situ trace element compositions for zircon from carbonatite and syenite are highly variable. The zircon displays slightly heavy REE (HREE)-enriched chondrite-normalized patterns with no Eu anomaly and various light REE (LREE) contents. In situ Th-Pb dating for zircon from the Miaoya complex by laser ablation ICP-MS yields ages of 442.6 ± 4.0 Ma (n = 53) for syenite and 426.5 ± 8.0 Ma (n = 23) for carbonatite. Monazite from carbonatite and syenite shows similar chondrite-normalized REE patterns and yields a consistent Th-Pb age of ~ 240 Ma. Based on petrographic and chemical composition, columbite from the carbonatite can be identified into two groups. The columbite dispersed within carbonatite is characterized by slightly LREE-enriched chondrite-normalized REE patterns, whereas columbite associated with apatite is characterized by LREE-depleted trends. Columbite has been further determined to have a weighted mean 206Pb/238U age of 232.8 ± 4.5 Ma (n = 9) using LA-ICP-MS. Detailed geochronological and chemical investigations suggest that there were two major episodes of magmatic/metasomatic activities in the formational history of the Miaoya carbonatite complex. The early alkaline magmatism emplaced in the Silurian was related to the opening of the Mianlue Ocean, whereas the late metasomatism or hydrothermal overprint occurred during the Triassic South Qinling orogeny. The latter serves as the major ore formation period for both REE (e.g., monazite) and Nb (e.g., columbite).
DS202107-1111
2021
Ying, Y.Lu, J., Chen, W., Ying, Y., Jiang, S., Zhao, K.Apatite texture and trace element chemistry of carbonatite-related REE deposits in China: implications for petrogenesis.Lithos, Vol. 398-399, 106276 pdfChinaREE

Abstract: Apatite is a ubiquitous mineral in carbonatites, and incorporates a variety of trace elements including rare earth elements (REEs). In this study, the textural and chemical variations of apatite were examined in order to trace the magmatic and hydrothermal petrogenesis of three carbonatite-related REE deposits: Shaxiongdong, Miaoya, and Bayan Obo. Various apatite textures were revealed by cathodoluminescence and back-scattered electron imaging. Magmatic apatite, which occurs predominantly in samples from Shaxiongdong, is euhedral, and commonly shows oscillatory or growth zonation with a yellow-green luminescent core and a violet luminescent rim. Euhedral to subhedral metasomatic apatite from Miaoya and Bayan Obo has a turbid texture, with the majority of grains associated with exsolved monazite. Hydrothermal apatite from Bayan Obo, typically occurring as aggregates in close association with fluorite and barite, is anhedral, with green or light violet luminescence. The different apatite textures are characterised by distinct trace element compositions. Magmatic apatite contains the highest concentrations of Mn (avg. 457 ppm) and Sr (avg. 18,285 ppm) and is characterised by a steeply inclined REE chondrite-normalised pattern. Metasomatic apatite, which has undergone in situ dissolution-reprecipitation, contains lower Mn (avg. 272 ppm) and Sr (avg. 9945 ppm) concentrations. It is characterised by highly variable REE trends with an La/SmN ratio varying from 0.13 to 5.61, and lower average La/YbN, La/SmN, and Sr/Y ratios (46, 2.2, and 18, respectively) than magmatic apatite. Hydrothermal apatite that was precipitated from a fluid is characterised by convex upward chondrite-normalised REE distributions with the lowest La/YbN, La/SmN, and Sr/Y ratios (13, 0.69, and 5.8, respectively). The average concentrations of Mn and Sr in this apatite are 270 and 6610 ppm, respectively. There are no Eu anomalies (Eu/Eu* = 0.97) in the chondrite-normalised REE plots for any of the analysed apatite samples. The combined textural and compositional variations of apatite in the three deposits reflect diverse magmatic and hydrothermal processes, including: 1) mineral fractionation contributing to core-rim zoning within the Shaxiongdong magmatic apatite; 2) dissolution-reprecipitation inducing monazite precipitation in Miaoya and Bayan Obo metasomatic apatite; and 3) coprecipitation with fluorite and barite from fluids generating the Bayan Obo hydrothermal apatite. A compilation of published apatite compositions from other rock types demonstrates that trace element compositions of apatite can be used to differentiate crystallisation environments and differentiate apatite from other rock types. Apatite from carbonatite has high Sr, REEs, La/YbN, Th/U, and Sr/Y, and no Eu anomaly, compared with apatite from igneous silicate rocks (except ultramafic rocks), and iron-oxide copper gold (IOCG) or iron-oxide apatite (IOA) deposits.
DS201809-2009
2018
Ying, Y-C.Chen, W., Lu, J., Jiang, S-Y., Ying, Y-C., Liu. Y-S.Radiogenic Pb reservoir contributes to the rare earth element (REE) enrichment in South Qinling carbonatites.Chemical Geology, Vol. 494, pp. 80-95.Chinacarbonatites

Abstract: Carbonatite and related alkaline silicate rocks contain one of the most significant rare earth element (REE) reserves in the world. It is well-known that these REE deposits are characterized by a strong light REE enrichment with a steep fractionation from La to Lu in the chondrite-normalized diagram. However, the origin of their REE enrichment remains debatable. The Shaxiongdong (SXD) carbonatite in the South Qinling orogenic belt hosts one of the most important REE deposits in central China. In this study, in situ chemical and isotopic data have been obtained for carbonate minerals from the complex. Our results show that calcite has variable trace element abundances, especially REEs. In situ Pb isotope data for calcite reveal extreme variations of 206Pb/204Pb (18.05-31.71) and 207Pb/204Pb (15.49-16.36) ratios. Interestingly, Pb isotope variations display positive correlations with REE enrichments [i.e., (La/Yb)N and (La/Nd)N]. Calcite with extreme radiogenic Pb isotopic compositions displays upper mantle C and O isotopic compositions (?13Cavg?=??5.74‰, ?18Oavg?=?7.13‰) and depleted 87Sr/86Sr isotopic ratios (~0.7030). The observed various REE enrichments accompanying the variable Pb isotopic composition within SXD calcite possibly result from a closed-system metasomatic event. The U-bearing mineral (i.e., pyrochlore) accumulating abundant uranogenic lead since their Silurian formation serves as the radiogenic Pb and LREE source for the metasomatism. Alternatively, the chemical and isotopic composition observed might suggest involvement of two mantle sources (PREMA and the distinct radiogenic Pb mantle reservoir).
DS201904-0725
2019
Ying, Y-C.Chen, W., Ying, Y-C., Bai, T., Zhang, J-J., Jiang, S-Y., Zhao, K-D.In situ major and trace element analysis of magnetite from carbonatite related complexes: implications for petrogenesis and ore genesis.Ore Geology Reviews, Vol. 107, pp. 30-40.Chinacarbonatite

Abstract: Magnetite (Fe3O4) is one of the most common accessory minerals in magmatic rocks, and it can accommodate a wide variety of major, minor and trace elements that can be measured by laser ablation ICP-MS. In this study, we investigate the chemical compositions of magnetite from four carbonatite complexes (Oka, Mushgai Khudag, Hongcheon and Bayan Obo). The minor elements (Mg, Ti, Al, Mn) in magnetite vary significantly both within and between different complexes. High field strength elements (Zr, Hf, Nb, Ta, U, Th) are generally depleted in magnetite from carbonatite complexes, whereas K, Rb, Cs, Ca and P are commonly below detection limits. V and Zn display significant variations from tens to thousands of ppm. Co, Ni and Ga are present in ppm or tens of ppm, whereas Cu, Sr, Y, Ba and Pb are characterized by sub-ppm levels. Mo and Ge are identified at the ppm level, whereas a consistent concentration of 2-5?ppm is observed for Ge. The determined chemical compositions of magnetite from carbonatite complexes are quite distinguishable compared to those formed in silicate and sulfide melts. This is clearly shown using multielement variation diagrams, and the distinct signatures of carbonatite-related magnetite include strong positive anomalies of Mn and Zn and negative anomalies of Cu, Co and Ga. The discriminant diagrams of Ti vs. Zr?+?Hf, Ti vs. Nb?+?Ta and Ni/Cr vs. Ti are applicable for distinguishing magmatic and hydrothermal magnetite in carbonatite-related environments. In addition, the discriminant diagram of Zn/Co vs. Cu/Mo and Cu vs. Zr?+?Hf can be used to distinguish carbonatite-related magnetite from magnetite that formed in other environments.
DS202006-0960
2020
Ying, Y-C.Ying, Y-C., Chen, W., Simonetti, A., Jiang, S-Y., Zhao, K-D.Significance of hydrothermal reworking for REE mineralization associated with carbonatite: constraints from in situ trace element and C-Sr isotope study of calcite and apatite from the Miaoya carbonatite complex (China).Geochimica et Cosmochimica Acta, in press available 45p. PdfChinadeposit - Miaoya

Abstract: A majority of carbonatite-related rare earth element (REE) deposits are found in cratonic margins and orogenic belts, and metasomatic/hydrothermal reworking is common in these deposits; however, the role of metasomatic processes involved in their formation remains unclear. Here, we present a comprehensive in situ chemical and isotopic (C-Sr) investigation of calcite and fluorapatite within the Miaoya carbonatite complex located in the South Qinling orogenic belt, with the aim to better define the role of late-stage metasomatic processes. Carbonatite at Miaoya commonly occurs as stocks and dykes intruded into associated syenite, and can be subdivided into equigranular (Type I) and inequigranular (Type II) calcite carbonatites. Calcite in Type I carbonatite is characterized by the highest Sr (up to ?22,000?ppm) and REE (195-542?ppm) concentrations with slight LREE-enriched chondrite normalized patterns [(La/Yb)N?=?2.1-5.2]. In situ C and Sr isotopic compositions of calcite in Type I carbonatite define a limited range (87Sr/86Sr?=?0.70344-0.70365; ?13C?=??7.1 to ?4.2 ‰) that are consistent with a mantle origin. Calcite in Type II carbonatite has lower Sr (1708-16322?ppm) and REEs (67-311?ppm) and displays variable LREE-depleted chondrite normalized REE patterns [(La/Yb)N?=?0.2-3.3; (La/Sm)N?=?0.2-2.0]. In situ 87Sr/86Sr and d13C isotopic compositions of Type II calcite are highly variable and range from 0.70350 to 0.70524 and ?7.0 to ?2.2 ‰, respectively. Fluorapatite in Type I and Type II carbonatites is characterized by similar trace-element and isotopic compositions. Both types of fluorapatite display variable trace element concentrations, especially LREE contents, whereas they exhibit relatively consistent near-chondritic Y/Ho ratios. Fluorapatite is characterized by consistent Sr isotopic compositions with a corresponding average 87Sr/86Sr ratio of 0.70359, which suggests that fluorapatite remained relatively closed in relation to contamination. The combined geochemical and isotopic data for calcite and fluorapatite from the Miaoya complex suggest that carbonatite-exsolved fluids together with possible syenite assimilation during the Mesozoic metasomatism overprinted the original trace-element and isotopic signatures acquired in the early Paleozoic magmatism. Hydrothermal reworking resulted in dissolution-reprecipitation of calcite and fluorapatite, which served as the dominant source of REE mineralization during the much younger metasomatic activity. The results from this study also suggest that carbonatites located in orogenic belts and cratonic edges possess a great potential for forming economic REE deposits, especially those that have undergone late-stage metasomatic reworking.
DS201312-0890
2012
Ying, Y-J.Su, B-X., Zhang, H-F., Ying, Y-J., Hu, Y., Santosh, M.Metasomatized lithospheric mantle beneath the western Qinling, central China: insight into carbonatite melts in the mantle.Journal of Geology, Vol. 120, 6, pp. 671-681.ChinaCarbonatite
DS1990-1614
1990
Yingwei FeiYingwei Fei, Mysen, B.O., Ho-Wang MaoExperimental determination of the FO2 of the graphite/diamond COH fluid buffer up to a pressure of 15 GPaCarnegie Institution Geophysical Laboratory Annual Report of the Director, No. 2200, pp. 54-58GlobalExperimental petrology, Graphite/diamond-COH
DS1993-1783
1993
Yingxin ZhouXiping Wu, Yingxin ZhouReserve estimation using neural network techniquesComputers and Geosciences, Vol. 19, No. 4, pp. 567-576GlobalOre reserve estimation, Geostatistics
DS200512-1219
2004
Yiniemi, J.Yiniemi, J., Kozlovskaya, E., Hjelt, S-E., Komminaho, K., Ushakov, A.Structure of the crust and uppermost mantle beneath southern FIn land revealed by analysis of local events registered by the SVEKALAPKO seismic array.Tectonophysics, Vol. 394, 1-2, pp. 41-110.Europe, FinlandGeophysics - seismic, tomography
DS201511-1890
2015
Yip, C.K.Yip, C.K., Thompson, K.S.Diavik Diamond Mines Inc. NI 43-101 Technical Report.Diavik Diamond Mines Inc., March 18, 128p. Available pdfCanada, Northwest TerritoriesMicrodiamonds - responses
DS200612-1571
2006
Yirgu, G.Yirgu, G., Ebinger, C.J., Maguire, P.K.H.The Afar volcanic province within the East African Rift sytem.Geological Society of London, Special Publication, No. 259, 336p. $ 200.00Africa, East AfricaMantle plume, paleomagnetism
DS201412-0752
2014
Yirgu, G.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
DS201702-0239
2017
Yirgu, G.Rooney, T.O., Nelson, W.R., Ayalew, D., Hanan, B., Yirgu, G., Kappelman, J.Melting the lithosphere: metasomes as a source for mantle derived magmas.Earth and Planetary Science Letters, Vol. 461, pp. 105-118.MantleMetasomatism

Abstract: Peridotite constitutes most of the Earth's upper mantle, and it is therefore unsurprising that most mantle-derived magmas exhibit evidence of past equilibrium with an olivine-dominated source. Although there is mounting evidence for the role of pyroxenite in magma generation within upwelling mantle plumes, a less documented non-peridotite source of melts are metasomatic veins (metasomes) within the lithospheric mantle. Here we present major and trace element analyses of 66 lavas erupted from a small Miocene shield volcano located within the Ethiopian flood basalt province. Erupted lavas are intercalated with lahars and pyroclastic horizons that are overlain by a later stage of activity manifested in small cinder cones and flows. The lavas form two distinctive petrographic and geochemical groups: (A) an olivine-phyric, low Ti group (1.7-2.7 wt.% TiO2; 4.0-13.6 wt.% MgO), which geochemically resembles most of the basalts in the region. These low Ti lavas are the only geochemical units identified in the later cinder cones and associated lava flows; (B) a clinopyroxene-phyric high Ti group (3.1-6.5 wt.% TiO2; 2.8-9.2 wt.% MgO), which resembles the Oligocene HT-2 flood basalts. This unit is found intercalated with low Ti lavas within the Miocene shield. In comparison to the low Ti group, the high Ti lavas exhibit a profound depletion in Ni, Cr, Al, and Si, and significant enrichment in Ca, Fe, V, and the most incompatible trace elements. A characteristic negative K anomaly in primitive-mantle normalized diagrams, and Na2O > K2O, suggests a source rich in amphibole, devoid of olivine, and perhaps containing some carbonate and magnetite. While melt generation during rift development in Ethiopia is strongly correlated with the thermo-chemical anomalies associated with the African Superplume, thermobaric destabilization and melting of mantle metasomes may also contribute to lithospheric thinning. In regions impacted by mantle plumes, such melts may be critical to weakening of the continental lithosphere and the development of rifts.
DS202003-0348
2020
Yium Y.C.Lee, C.W.Y., Cheng, J., Yium Y.C., Chan, K., Lau, D., Tang, W.C., Cheng, K.W,m Kong, T., Hui, T.K.C., Jelezko, F.Correlation between EPR spectra and coloration of natural diamonds.Diamond & Related Materials, Vol. 103, 13p. PdfGlobaldiamond colour

Abstract: White diamonds color grading is one of the basic diamond evaluations. The color value based on a scale that ranges from D to Z, with D being the more colorless and more valuable, among other qualifications. As the diamond grade moves on this scale, its color appears more yellow progressively. This yellowish color, present only in Type I diamonds, is mainly due to the nitrogen related defects such as N3 center and C-center. The current color grading system is based on a visual method, where gemologist compares the sample with a Master Color set. However, this method is very subjective. Several defects responsible for light absorption in diamond are carrying electron spin and appear in Electron Paramagnetic Resonance (EPR) spectrum. In this study, we developed a new EPR based technique for a quantitative measurement of N3 center and C-center in diamond through quantitative EPR spectroscopy. The correlation between EPR spectra and color grades of diamond was established.
DS201708-1794
2017
Yi-Xiang, C.Yi-Xiang, C.Tracing Mg-rich fluids by Mg-O isotopes at slab-mantle interface in continental subduction zones: insights from the Mg-metasomatic rocks in western and eastern11th. International Kimberlite Conference, PosterChinaSubduction, metasomatism

Abstract: Fluids are important for mass transfer at the slab–mantle interface in subduction zones. However, it is usually difficult to trace fluids from specific sources in a subducting slab, especially those derived from dehydration of serpentinite. Coesite-bearing whiteschist at Dora-Maira in the Western Alps is characterized by strong Mg enrichment relative to the country rocks, which requires infiltration of Mg-rich fluids into the supracrustal rock. In order to constrain the origin of such Mg-rich fluids, we have performed an integrated study of whole-rock Mg and O isotopes, zircon U–Pb ages and O isotopes for the whiteschist and related rocks. Zircons in the whiteschist show two groups of U–Pb ages at ?262 Ma and ?34 Ma, respectively, for relict and newly grown domains. The Permian U–Pb ages of relict magmatic domains are consistent with the protolith age of host metagranite, suggesting that their common protolith is the Permian granite. The Tertiary U–Pb ages occur in coesite-bearing metamorphic domains, consistent with the known age for ultrahigh-pressure metamorphism. The metamorphic domains have ?18O values of ‰5.8–6.8‰, whereas the relict magmatic domains have high ?18O values of ‰?10‰. Such high ?18O values are also characteristic of the metagranite, indicating that the whiteschist protolith underwent metasomatism by metamorphic fluids with low ?18O value of f ‰?2–4‰. The whiteschist mostly has whole-rock ?26Mg values of ?0.07 to 0.72‰, considerably higher than country-rock ?26Mg values of ?0.54 to ‰?0.11‰. Thus, the metamorphic fluids are not only rich in Mg but also heavy in Mg isotopes. They were probably derived from the breakdown of Mg-rich hydrous minerals such as talc and antigorite in serpentinite at the slab–mantle interface in the subduction channel. Therefore, the dehydration of mantle wedge serpentinite during the subduction and exhumation of continental crust can provide the Mg-rich fluids responsible for the metasomatism of crustal rocks at subarc depths.
DS200412-0534
2004
Y-JFan, 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
DS201904-0804
2017
Y-JZhou, Z., Wang, G., Di, Y-J,m Gu, Y-C., Zhang, D., Zhu, W-p., Liu, C., Wu, C., Li, H., Chen, L.-z.Discovery of Mesoproterozoic kimberlite from Dorbed Benner, Inner Mongolia and its tectonic significance.Geochemistry International, doi:10.1002/gi.2939 14p.China, 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.”
DS1991-1475
1991
YkRuoff, A., Luo, H., Vanderbose, C., Vohra, YkGenerating near earth core pressures with Type IIA diamondsApplied Phys. Letters, Vol. 59, np. 2, November 18, pp. 2681-2682MantleDiamond morphology, Experimental petrology
DS2001-1285
2001
Yliniemi, J.Yliniemi, J., Tiira, T., Luosto, Komminaho, Giese, et al.EUROBRIDGE'95: deep seismic profiling within the East European CratonTectonophysics, Vol. 339, No. 1-2, pp. 153-75.EuropeGeophysics - seismics, Craton
DS2002-0896
2002
Yliniemi, J.Kozlovskaya, E., taran, L.N., Yliniemi, J., Giese, R., Karatayev, G.I.Deep structure of the crust along the Fennoscandia Sarmatia Junction Zone ( CentralTectonophysics, Vol. 358,1-4,pp. 97-120.Fennoscandia, Europe, UralsTectonics
DS200712-0483
2007
Yliniemi, J.Janik, T., Kozlovskaya, E., Yliniemi, J.Crust mantle boundary in the central Fennoscandian shield: constraints from wide angle P and S wave velocity models and new results of reflection profiling in FinlandJournal of Geophysical Research, Vol. 112, B4, B04302.Europe, FinlandGeophysics - seismics
DS1994-0183
1994
Yobou, R.Bonin, B., Yobou, R.The Proterozoic quartz syenite nepheline syenite association of Ninakri, Cote d'Ivoire, West Africa.Geological Association of Canada (GAC) Abstract Volume, Vol. 19, p.GlobalAlkaline rocks, Ninakri
DS200812-0022
2008
Yobou, R.Allialy, M.E., Djro, S.C., Yavouba, C., Konamelan, A.N., Pothin, K.B., Yao, D.B., Yobou, R.Comparative geochemistry of Seguela kimberlites, South Africa Group II kimberlites and other worldwide kimberlites.9IKC.com, 3p. extended abstractAfrica, West Africa, Ivory CoastDeposit - Bobi, Toubabouko
DS200612-1572
2006
Yoburn, J.B.Yoburn, J.B., Fouch, M.J., Arrowsmith, J.R., Keller, G.R.A new GIS driven geophysical database for the southwestern United States.In: Sinha, A.K. Geoinformatics: data to knowledge, GSA Special Paper, 397, 397,pp.249-268.United StatesGeophysics - data
DS1980-0067
1980
Yoder, H.S. Jr.Boctor, N.Z., Yoder, H.S. Jr.Distribution of Rare Earth Elements in Perovskite from Oka Carbonatite, quebec.Carnegie Institute Yearbook, FOR 1979 PP. 304-306.Canada, QuebecRelated Rocks, Mineralogy, Analyses
DS1982-0106
1982
Yoder, H.S. Jr.Boctor, N.Z., Yoder, H.S. Jr.Distribution of Rare Earth Elements in Perovskite from Melilite Bearing Rocks.Carnegie Institute Yearbook, FOR 1981 PP. 369-371.South AfricaRare Earth Elements (ree), Mineral Chemistry
DS1983-0137
1983
Yoder, H.S. Jr.Boctor, N.Z., Yoder, H.S. Jr.Petrology of Olivine Melilitites from Saltpetre Kop and Sutherland Commage Cape Province, South Africa.Carnegie Institute Yearbook, FOR 1982, PP. 264-267.South AfricaPetrology
DS1986-0081
1986
Yoder, H.S. Jr.Boctor, N.Z., Yoder, H.S. Jr.Petrology of some melilite bearing rocks from Cape Province Republic of South Africa: relationship to kimberlitesAmerican Journal of Science, Vol. 286, September pp. 513-539South AfricaMelilite
DS1986-0887
1986
Yoder, H.S. Jr.Yoder, H.S. Jr.Potassium rich rocks: phase analysis and heteromorphic relationsJournal of Petrology, Vol. 27, No. 5, pp. 1215-1228GlobalAlkaline rocks
DS1987-0823
1987
Yoder, H.S. Jr.Yoder, H.S. Jr., Boctor, N.Z., Hofmeister, A.Barium and titanium micas from olivine melilitite: a potential new endmember micaEos, abstractSouth AfricaSaltpetre Kop
DS1988-0776
1988
Yoder, H.S. Jr.Yoder, H.S. Jr.The great basaltic 'floods'South African Journal of Geology, Vol. 91, No. 2, June pp. 139-156. Database # 17382GlobalBasalt, Genesis
DS1989-1672
1989
Yoder, H.S. Jr.Yoder, H.S. Jr.Igneous and metamorphic facies of potassium rich rocks: coexisting assemblages in kalsilite-forsterite Larnite-Quartz at 950 deg C and 2KB with and without H2OGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A50. (abstract.)GlobalMelilite, Sanidine
DS1960-0883
1967
Yoder, H.S.JR.Tilley, C.E., Yoder, H.S.JR.The Pyroxenite Facies Conversion of Volcanic and Subvolcanic Melilite Bearing and Other Alkali Ultramafic Assemblages.Carnegie Institute Yearbook, FOR 1966, PP. 457-460.GlobalResearch
DS1960-0898
1967
Yoder, H.S.JR.Yoder, H.S.JR.Akermanite and Related Melilite Bearing AssemblagesCarnegie Institute Yearbook, FOR 1966, PP. 471-477.GlobalResearch
DS1960-1054
1968
Yoder, H.S.JR.Yoder, H.S.JR.Anorthite Akermanite and Albite Soda Melilite Reaction Relations.Carnegie Institute Yearbook, FOR 1967, PP. 105-108.GlobalResearch
DS1960-1055
1968
Yoder, H.S.JR.Yoder, H.S.JR., Schairer, J.F.The Melilite Plagioclase Incompatibility Dilemma in Igneousrocks.Carnegie Institute Yearbook, FOR 1968, PP. 101-105.GlobalResearch
DS1970-0857
1973
Yoder, H.S.JR.Yoder, H.S.JR.Akermanite-co2 Relationship of Melilite Bearing Rocks to Kimberlite.Carnegie Institute Yearbook, FOR 1972, PP. 449-457.Russia, South Africa, Canada, Quebec, Brome MountainExperimental Petrology
DS1975-0645
1977
Yoder, H.S.JR.Velde, D., Yoder, H.S.JR.Melilite and Melilite Bearing Igneous RocksCarnegie Institute Yearbook, FOR 1976, PP. 478-485.Hawaii, Canary IslandsRelated Rocks'mineralogy
DS1983-0643
1983
Yoder, H.S.JR.Yoder, H.S.JR., Boctor, N.Z.Olivine Melilitite from Saltpetre Kop, South AfricaEos, Vol. 64, No. 18, MAY 3RD. P. 341. (abstract.).South AfricaBlank
DS1985-0757
1985
Yoder, H.S.JR.Yoder, H.S.JR.Melilite Bearing LamprophyresGeological Association of Canada (GAC)., Vol. 10, P. A70. (abstract.).GlobalExperimental Petrology
DS1990-1615
1990
Yoder, H.S.Jr.Yoder, H.S.Jr.Potassium-rich rock diversity and experimentally determined contiguityCarnegie Institution Geophysical Laboratory Annual Report of the Director, No. 2200, pp. 76-80GlobalExperimental petrology, Kimberlite, phlogopite, monticellite
DS1991-0748
1991
Yoder, H.S.Jr.Huckenholz, H.G., Yoder, H.S.Jr., Kunzmann, T., Seiberl, W.The akermanite-gehlenite sodium melilite join at 950 C and 5 Kbar in the presence of CO2 and H2OCarnegie Institute Annual Report of the Director Geophysical Laboratory, No. 2250, pp. 75-81GlobalExperimental petrology, Melilite
DS1991-1912
1991
Yoder, H.S.Jr.Yoder, H.S.Jr.Potassium-rich rock Inter relationships determined experimentallyGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC)/SEG Annual Meeting May 27-29. Toronto, Ontario, Abstract, Vol. 16, p. A136. AbstractGlobalLamproite, Experimental petrology
DS200412-1967
2003
Yogiso, T.Tatsumi, Y., Yogiso, T.The subduction factory: its role in the evolution of the Earth's crust and mantle.Geological Society of London, Special Publication, Larter, Leat Intra-Oceanic Subduction, No. 219, pp. 55-80.MantleSubduction
DS201707-1377
2017
Yogodzinski, G.Turner, M., Turner, S., Blatter, D., Maury, R., Perfit, M., Yogodzinski, G.Water contents of clinopyroxenes from sub-arc mantle peridotitesIsland Arc, in press available 2p.Europe, Francemassif

Abstract: One poorly constrained reservoir of the Earth's water budget is that of clinopyroxene in metasomatised, mantle peridotites. This study presents reconnaissance Sensitive High-Resolution, Ion Microprobe–Stable Isotope (SHRIMP–SI) determinations of the H2O contents of (dominantly) clinopyroxenes in rare mantle xenoliths from four different subduction zones, i.e. Mexico, Kamchatka, Philippines, and New Britain (Tabar-Feni island chain) as well as one intra-plate setting (western Victoria). All of the sub-arc xenoliths have been metasomatised and carry strong arc trace element signatures. Average measured H2O contents of the pyroxenes range from 70 ppm to 510?ppm whereas calculated bulk H2O contents range from 88 ppm to 3?737?ppm if the variable presence of amphibole is taken into account. In contrast, the intra-plate, continental mantle xenolith from western Victoria has higher water contents (3?447?ppm) but was metasomatised by alkali and/or carbonatitic melts and does not carry a subduction-related signature. Material similar to the sub-arc peridotites can either be accreted to the base of the lithosphere or potentially be transported by convection deeper into the mantle where it will lose water due to amphibole breakdown.
DS201911-2562
2019
Yogodzinski, G.Siegrist, M., Yogodzinski, G., Bizimis, M., Fournelle, J., Churikova, T., Dektor, C., Mobley, R.Fragments of metasomatized forearc: origin and implications of mafic and ultramafic xenoliths from Kharchinsky volcano, Kamchatka.Geochemistry, Geophysics, Geosystems, Vol. 20, 9, pp. 4426-4456.Russiaxenoliths

Abstract: This paper presents the results of a study of rare rock fragments (xenoliths) that were transported from the Earth's deep interior to the surface during an eruption of Kharchinsky volcano, Kamchatka. The chemical compositions, mineralogy, and textures of the samples were studied with the goal of understanding the processes that affected rocks, which may play a role in the formation of magmas in the Kamchatka subduction zone. The key process that affected the xenoliths involved the addition of fluids and dissolved elements to the samples at temperatures of 500-700 °C. These fluids are derived from seawater that was transported to 30? to 50?km depths by subduction of the Pacific Plate beneath Kamchatka. Subsequent to the addition of fluid, there was a shift in the position of the Kamchatka?Pacific Plate boundary that led to an increase in temperature and the formation of small quantities of melt that crystallized to a distinctive group of secondary minerals that are present in the samples and that postdate (overprint) the initial effects of fluid addition. The final step in the evolution of the samples was infiltration by an Fe? and Mg?rich magma that crystallized principally amphibole?group minerals.
DS1995-2105
1995
Yogodzinski, G.M.Yogodzinski, G.M., Kay, R.W., Volynets, O.N., KoloskovMagnesian andesite in the western Aleutian Komandorsky region: Implications for slab melting - mantle wedge.Geological Society of America (GSA) Bulletin., Vol. 107, No. 5, pp. 509-519.Russia, AleutiansSubduction, Slab melt
DS200512-0927
2005
Yogodzinski, G.M.Saha, A., Basu, A.R., Jacobsen, S.B., Poreda, R.J., Yin, Q.Z., Yogodzinski, G.M.Slab devolatization and Os and Pb mobility in the mantle wedge of the Kamchatka arc.Earth and Planetary Science Letters, Advanced in press,Russia, KamchatkaGeochronology, slab
DS200512-0088
2005
Yogodzinski, Y.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
DS2001-0679
2001
Yokayama, Zyryanov..Letnikov, F.A., Watanabe, Kotov, Yokayama, Zyryanov..Problem of the age of metamorphic rocks of the Kokchetav Block, northern Kazakhstan.Doklady, Vol. 381A, Nov-Dec. pp. 1025-7.Russia, KazakhstanGeochronology
DS2002-1398
2002
Yokochi, R.Sano, Y., Yokochi, R., Terada, K., Chaves, M.L.,OzimaIon microprobe Pb Pb dating of carbonado, polycrystalline diamondPrecambrian Research, Vol. 113, No. 1-2, pp. 155-68.GlobalCarbonado, lead, geochronology
DS200412-2183
2004
Yokochi, R.Yokochi, R., Marty, B.A determination of the neon isotopic composition of the deep mantle.Earth and Planetary Science Letters, Vol. 225, 1-2, pp. 77-88.MantleGeochronology
DS1989-0017
1989
Yokota, S.Albin, S., Watkins, L., Ravi, K., Yokota, S.Diamond films for laser hardeningAppl. Phys. Letters, Vol. 54, No. 26, June 26, pp. 2728-2730GlobalDiamond filM., Synthetic diamonds
DS200412-0843
2004
Yokoyama, K.Hokada, T., Misawa, K., Yokoyama, K., Shiraishi, K., Yamaguchi, A.SHRIMP and electron microprobe chronology of UHT metamorphism in the Napier Complex, East Antarctica implications for zircon groContributions to Mineralogy and Petrology, Vol. 147, 1, pp. 1-20.AntarcticaGeochronology
DS200512-0934
2005
Yokoyama, K.Santosj, M., Tanaka, K., Yokoyama, K., Collins, A.S.Late Neoproterozoic Cambrian felsic magmatism along transcrustral shear zones in southern India: U Pb electron microprobe ages implications for amalagamtionGondwana Research, Vol. 8, 1, pp. 31-42.IndiaGeochronology, Gondwana supercontinent
DS2001-1286
2001
Yokoyama, M.Yokoyama, M., Liu, Y., Halim, N., Otofuji, Y.Paleomagnetic study of Upper Jurassic rocks from Sichuan Basin: tectonic aspects for collision....Earth and Planetary Science Letters, Vol. 193, No. 3-4, pp.273-85.ChinaTectonics, Block - Yangtze and North China
DS201607-1305
2016
Yokoyama, Y.Lee, C-T. A., Yeung, L., McKenzie, N.R., Yokoyama, Y., Ozaki, K.Two step rise of atmospheric oxygen linked to the growth of continents. (carbon)Nature Geoscience, Vol. 9, 6, pp. 417-424.MantleCarbon

Abstract: Earth owes its oxygenated atmosphere to its unique claim on life, but how the atmosphere evolved from an initially oxygen-free state remains unresolved. The rise of atmospheric oxygen occurred in two stages: approximately 2.5 to 2.0 billion years ago during the Great Oxidation Event and roughly 2 billion years later during the Neoproterozoic Oxygenation Event. We propose that the formation of continents about 2.7 to 2.5 billion years ago, perhaps due to the initiation of plate tectonics, may have led to oxygenation by the following mechanisms. In the first stage, the change in composition of Earth's crust from iron- and magnesium-rich mafic rocks to feldspar- and quartz-rich felsic rocks could have caused a decrease in the oxidative efficiency of the Earth's surface, allowing atmospheric O2 to rise. Over the next billion years, as carbon steadily accumulated on the continents, metamorphic and magmatic reactions within this growing continental carbon reservoir facilitated a gradual increase in the total long-term input of CO2 to the ocean -atmosphere system. Given that O2 is produced during organic carbon burial, the increased CO2 input may have triggered a second rise in O2. A two-step rise in atmospheric O2 may therefore be a natural consequence of plate tectonics, continent formation and the growth of a crustal carbon reservoir.
DS1994-1969
1994
Yolkin, E.A.Yolkin, E.A., et al.Paleogeographic reconstruction of western Altai Sayan area in the Ordovician -Silurian, Devonian geodynamicsRussian Geology and Geophysics, Vol. 35, No. 7-8, pp. 100-124China, AltaiTectonic, Paleoreconstruction
DS202106-0974
2021
Yomba, A.E.Tchoukeu, C.D.N., Baseka, C.A., Djomani, Y.P., Rousse, S., Etame,J., Llubes, M., Seoane,L., Mbang, C.S., Yomba, A.E.Crustal thickness, depth to the bottom of magnetic sources and thermal structure of the crust from Cameroon to Central African Republic: preliminary results for a better understanding of the origin of the Bangui Magnetic Anomaly.Journal of African Earth Sciences, Vol. 179, 104206, 21p. pdfAfrica, Cameroon, Central African Republicgeophysics

Abstract: The Bangui Magnetic Anomaly (BMA) is one of the largest magnetic anomalies in the world whose origin is still not known. This research investigated the crustal thickness, Curie depths and thermal structures in the Central African sub-regions - Cameroon, Central African Republic and adjacent countries - which are largely characterized by the Bangui Magnetic Anomaly. To achieve a better understanding and clearer idea of the location of the possible sources of the BMA, analyses of geothermal structures were conducted. Two potential methods were used: gravity to evaluate the crustal thickness and magnetics for geothermal analysis. Spectral analysis of gravity data shows that crustal thickness range between 14 and 55 km. The highest depths were found in Central African Republic. The lower values of crustal thickness were obtained in South-Chad basin with a minimum of roughly 14 km. Geothermal analysis is carried out using the Curie point depth, thermal gradient and heat-flow evaluations. The results show that the BMA is related to a thick crust of roughly 40 km. Depth to the bottom of possible sources does not exceed the lower crust. The mean Curie point depth estimated is 38 km with an error of ±2 km. Geothermal results also show the difference in the thermal behaviour between the crust in the Pan African and Precambrian domain. The mobile zone which constitutes the Pan African domain is associated with a thin crust of high heat-flow values of 65 mW/m2. However, the Precambrian domain beneath the BMA is associated with a thick crust with lower heat-flow values (roughly 45 mW/m2). The difference between crustal thickness and Curie point depths shows that all the sources of the BMA are crustal. The present results are in favour of a geological origin for the Bangui Magnetic anomaly.
DS200612-0005
2006
Yoneda, A.Aizawa, Y., Yoneda, A.P V T equation of state of MgSiO3 perovskite and MgO periclase: implications for lower mantle composition.Physics of the Earth and Planetary Interiors, Vol. 155, 1-2, pp. 87-95.MantleGeophysics - seismics, model
DS200912-0840
2009
Yoneda, A.Yoneda, A., Chen, G., Spetzler, H.A., Getting, I.G.The effect of composition, temperature and pressure on the elasticity of olivine and garnet: implications for interpreting seismic velocity variations in mantle.mantleplumes.org, 8p.MantleGeophysics - seismics
DS201805-0968
2018
Yoneda, A.Ono, K., Harada, Y., Yoneda, A., Yamamoto, J., Yoshiasa, A., Sugiyama, K., Arima, H., Watanabe, T.Determination of elastic constants of single crystal chromian spinel by resonant ultrasound spectroscopy and implications for fluid inclusion geobarometry.Physics and Chemistry of Minerals, Vol. 45, 3, pp. 237-247.Technologyxenolths

Abstract: We determined elastic constants of a single-crystal chromian spinel at temperatures from ?15 to 45 °C through the Rectangular Parallelepiped Resonance method. The sample is a natural chromian spinel, which was separated from a mantle xenolith. Elastic constants at an ambient temperature (T = 24.0 °C) are C 11 = 264.8(1.7) GPa, C 12 = 154.5(1.8) GPa and C 44 = 142.6(0.3) GPa. All the elastic constants decrease linearly with increasing temperature. The temperature derivatives are dC 11/dT = ?0.049(2) GPa/°K, dC 12/dT = ?0.019(1) GPa/°K and dC 44/dT = ?0.020(1) GPa/°K. As an implication of the elastic constants, we applied them to the correction of a fluid inclusion geobarometry, which utilizes residual pressure of fluid inclusion as a depth scale. Before entrainment by a magma, the fluid inclusions must have the identical fluid density in constituent minerals of a xenolith. It has been, however, pointed out that fluid density of fluid inclusions significantly varies with host mineral species. The present study elucidates that elastic constants and thermal expansion coefficients cannot explain the difference in fluid density among mineral species. The density difference would reflect the difference in the degree of plastic deformation in the minerals.
DS202003-0371
2020
Yoneda, A.Xie, L. , Yoneda, A., Andraught, D.Formation of bridgmanite-enriched layer at the top lower-mantle during magma ocean solificiation.Nature Communications, Vol. 11, pp. 1-10.Mantlebridgmanite

Abstract: Thermochemical heterogeneities detected today in the Earth’s mantle could arise from ongoing partial melting in different mantle regions. A major open question, however, is the level of chemical stratification inherited from an early magma-ocean (MO) solidification. Here we show that the MO crystallized homogeneously in the deep mantle, but with chemical fractionation at depths around 1000?km and in the upper mantle. Our arguments are based on accurate measurements of the viscosity of melts with forsterite, enstatite and diopside compositions up to ~30?GPa and more than 3000?K at synchrotron X-ray facilities. Fractional solidification would induce the formation of a bridgmanite-enriched layer at ~1000?km depth. This layer may have resisted to mantle mixing by convection and cause the reported viscosity peak and anomalous dynamic impedance. On the other hand, fractional solidification in the upper mantle would have favored the formation of the first crust.
DS200812-1150
2008
Yong, J.F.Tang, Y.J., Zhang, H.F., Yong, J.F., Zhang, J., Liu, X.M.Refertilization of ancient lithosphere mantle beneath the central North Chin a craton: evidence from petrology and geochemistry of peridotite xenoliths.Lithos, Vol. 101, 3-4, pp. 435-452.ChinaGeochemistry
DS202007-1159
2020
Yong, L.Li, W, Yang, Z., Chiaradia, M., Yong, L., Caho, Yu., Zhang, J.Redox state of southern Tibetan mantle and ultrapotassic magmas. Lhasa TerraneGeology, Vol. 48, 7, pp. 733-736. pdfAsia, Tibetalkaline rocks

Abstract: The redox state of Earth’s upper mantle in several tectonic settings, such as cratonic mantle, oceanic mantle, and mantle wedges beneath magmatic arcs, has been well documented. In contrast, oxygen fugacity (graphic) data of upper mantle under orogens worldwide are rare, and the mechanism responsible for the mantle graphic condition under orogens is not well constrained. In this study, we investigated the graphic of mantle xenoliths derived from the southern Tibetan lithospheric mantle beneath the Himalayan orogen, and that of postcollisional ultrapotassic volcanic rocks hosting the xenoliths. The graphic of mantle xenoliths ranges from ?FMQ = +0.5 to +1.2 (where ?FMQ is the deviation of log graphic from the fayalite-magnetite-quartz buffer), indicating that the southern Tibetan lithospheric mantle is more oxidized than cratonic and oceanic mantle, and it falls within the typical range of mantle wedge graphic values. Mineralogical evidence suggests that water-rich fluids and sediment melts liberated from both the subducting Neo-Tethyan oceanic slab and perhaps the Indian continental plate could have oxidized the southern Tibetan lithospheric mantle. The graphic conditions of ultrapotassic magmas show a shift toward more oxidized conditions during ascent (from ?FMQ = +0.8 to +3.0). Crustal evolution processes (e.g., fractionation) could influence magmatic graphic, and thus the redox state of mantle-derived magma may not simply represent its mantle source.
DS1992-1722
1992
Yong, R.N.Yong, R.N., Mohamed, A.M.O., Warkentin, B.P.Principles of contaminant transport in soilsElsevier, 327p. approx. $ 150.00 United StatesGlobalBook -ad, Landfill, environment
DS1995-2106
1995
Yong, S.Yong, S., Bourne, J.H.Possible compositional differences Archean Post Archean granulite terranes based on discriminant analysisMineralogy and Petrology, Vol. 54, No. 3-4, pp. 175-190AustraliaArchean, Geochemistry
DS201912-2836
2019
Yong, W.Yong, W., Secco, R.A., Littleton, J.A.H., Silber, R.A., Reynaold, E.The iron invariance: implications for thermal convection in Earth's core.Geophysical Research Letters, Vol. 46, 20, pp. 11065-110670.Mantlegeothermometry

Abstract: Earth's magnetic field is produced by a dynamo in the core that requires motion of the fluid Fe alloy. Both thermal convection, arising from the transport of heat in excess of conducted heat, and compositional convection, arising from light element exsolution at the freezing inner core boundary, are suggested as energy sources. The contribution of thermal convection (possibly ranging from nothing to significant) depends on thermal conductivity of the outer core. Our experimental measurements of electrical resistivity of solid and liquid Fe at high pressures show that resistivity is constant along the pressure?dependent melting boundary of Fe. Using our derived thermal conductivity value at the inner core (freezing) boundary, we calculate the heat conducted in the liquid outer core and find that thermal convection is needed to carry additional heat through the outer core to match the heat extracted through the core?mantle boundary.
DS2003-1530
2003
Yong, X.Yong, X., De Lian Liu, Dai, Jin-XingExtremely h2 rich fluid inclusions in eclogite from the Dabie Shan orogenic belt, EasternJournal of the Geological Society of India, Vol. 61, 1, Jan., pp. 101-102.ChinaUHP
DS2000-1043
2000
YongbeiYongbei, Zhang, Zhao, C., Xu, C.The characteristics of apatitic carbonatite of Proterozoic Kunyang Rift, Yunnan China.Igc 30th. Brasil, Aug. abstract only 1p.ChinaCarbonatititic tuff
DS1995-2107
1995
Yongfei, Z.Yongfei, Z.Oxygen isotope fractionation in TiO2, polymorphs and application to geothermometry of eclogites.Chinese Journal of Geochemistry, Vol. 14, No. 1, pp. 1-12.GlobalGeothermometry, Eclogites
DS1994-1970
1994
Yonggian ZhaiYonggian Zhai, Halls, H.C.Multiple episodes of dike emplacement along the northwestern margin of the Superior Province.Journal of Geophysical Research, Vol. 99, No. B11, Nov. 10, pp. 21, 717-732.ManitobaDikes, Molson swarm
DS200612-1573
2006
Yongliang, A.Yongliang, A., Lifei, Z., Li, X., Qu, J.Geochemical characteristics and tectonic implications of HP UHP eclogites and blueschists in southwestern Tian Shan China.Progress in Natural Science, Vol. 16, 6, June pp. 624-632.ChinaUHP
DS2003-1568
2003
Yongshun LiuZou, H.,Reid, M.R., Yongshun Liu, Yupeng Yao, Xisheng Xu, Qicheng FanConstraints on the origin of historic potassic basalts from northeast Chin a by U ThChemical Geology, Vol. 200, 1-2, Oct. 16, pp. 189-201.ChinaPhlogopite garnet bearing peridotite, melting, metasoma
DS200412-2239
2003
Yongshun LiuZou, H.,Reid, M.R., Yongshun Liu, Yupeng Yao, Xisheng Xu, Qicheng FanConstraints on the origin of historic potassic basalts from northeast Chin a by U Th disequilibrium data.Chemical Geology, Vol. 200, 1-2, Oct. 16, pp. 189-201.ChinaPhlogopite garnet bearing peridotite, melting, metasoma
DS201603-0390
2016
Yongue, R.F.Kanouo, N.S., Ekomane, E., Yongue, R.F., Njonfang, E., Zaw, K., Changian, M., Ghogomu, T.R., Lentz, D.R., Venkatesh, A.S.Trace elements in corundum, chrysoberyl, and zircon: application to mineral exploration and provenance study of the western Mamfe gem clastic deposits ( SW Cameroon, Central Africa).Journal of African Earth Sciences, Vol. 113, pp. 35-50.Africa, CameroonGeochemistry

Abstract: Trace element abundances in three indicator minerals (corundum, chrysoberyl, and zircon grains) from the western Mamfe gem placers, as determined by LA-ICP-MS analytical techniques, are shown to be sensitive to their crystallization conditions and source rock types. Corundum is dominantly composed of Al (standardized at 529,300 ppm), Fe (2496-12,899 ppm), and Ti (46-7070 ppm). Among element ratios, Fe/Mg (73-1107), Fe/Ti (0.5-245.0), Ti/Mg (1-175), and Ga/Mg (4-90) are generally higher whereas, Cr/Ga (<0.072) is low. The Fe (?12,899), Ga (?398), Mg (2-62), Cr (1.1-33.0), and V (3.0-93.0) contents (in ppm) mostly typify corundum grains formed in magmatic rocks, although some are metamorphic affiliated. A very higher Ti and significantly low Ga, Ta and Nb contents in some blue grains, suggest interesting concentrations of those high-tech metals in their source rocks. Chrysoberyl is dominantly composed of Al (standardized at 425,000 ppm) and Be (62701-64371 ppm). Iron (7605-9225 ppm), Sn (502-3394 ppm), and Ti (33-2251 ppm) contents are high, whereas Ga (333-608 ppm), Ta (<456.0 ppm), and Nb (<3.0 ppm) are significantly low. The high (Be and Sn) and significantly low Ga-Rb abundances, and Ta > Nb in the western Mamfe chrysoberyls show that they were crystallized in granitic pegmatites, with some of those source rocks being enriched in Ta and Sn. Zirconium oxide (ZrO2: standardized at 66.1 wt.%)) is the only major oxide in analysed coarse-grained zircons. Within the minor elementary suites: Hf (4576-12,565 ppm) and Y (48-2805 ppm) contents are significantly high. The trace element suites include: Th (7-1565 ppm), U (13-687 ppm), and ?REE (50-2161 ppm), whose values are significantly low. The (Yb/Sm)N, Ce/Ce*, and Eu/Eu* anomalies range from 1.0 to 227.0, 0 to 308, and 0.08 to 1.7 respectively. They are Hf-Y-HREE enriched and depleted zircons mainly crystallized in magmatic oxidized environments. They were mainly sorted from granitoids, syenites and kimberlites.
DS2003-1531
2003
Yong-XYong-X, Liu, D-L., Dai, J-X.Extremely H2 rich fluid inclusions in eclogite from Dabie Shan orogenic belt, easternJournal of the Geological Society of India, Vol. 61, Jan. pp. 101-2.China, eastEclogite
DS200412-2184
2003
Yong-XYong-X, Liu, D-L., Dai, J-X.Extremely H2 rich fluid inclusions in eclogite from Dabie Shan orogenic belt, eastern China.Journal of the Geological Society of India, Vol. 61, Jan. pp. 101-2.ChinaEclogite
DS1993-1790
1993
Yongzheng LuYang, Jianjun, Godard, G., Kienast, J-R., Yongzheng Lu, JinxiongUltrahigh pressure ( 60 Kbar) magnesite-bearing garnet peridotites from northeastern Jiangsu, China.Journal of Geology, Vol. 101, No. 5, September pp. 541-554.ChinaEclogites, Shandong Province
DS201607-1320
2016
Yonkee, A.Weil, A.B., Yonkee, A., Schultz, M.Tectonic evolution of a Laramide transverse structural zone: Sweetwater Arch, south central Wyoming.Tectonics, Vol. 35, 5, pp. 1090-1120.United States, Wyoming, Colorado PlateauSweetwater Arch

Abstract: Structural, anisotropy of magnetic susceptibility (AMS), and paleomagnetic data record patterns of layer-parallel shortening (LPS), vertical-axis rotation, and regional fault-fold evolution across the Sweetwater Arch, a major west to WNW trending, basement-cored Laramide uplift in Wyoming. The southern arch flank is bounded by a WNW striking reverse fault zone that imbricated basement and cover rocks, the northern flank is bounded by a west striking fault zone with a component of strike-slip and NW trending en echelon folds, and the eastern plunge transitions into an area of multiple-trending faults and folds. Synorogenic strata record major arch uplift from Maastrichtian to Early Eocene time, followed by arch collapse. LPS, with development of systematic minor fault sets and AMS lineations, preceded large-scale folding. LPS directions, estimated from both minor fault and AMS data, were oriented WSW along the northern flank, subparallel to Laramide regional shortening, but were refracted to the SSW along the southern flank, and to the west along the eastern arch plunge. Additional minor faults developed along steep fold limbs during continued shortening, with directions remaining SSW along the southern flank but becoming more variable along the eastern plunge where an increasingly heterogeneous stress field developed as additional faults were activated along basement heterogeneities. Vertical-axis rotation was limited along the arch flanks, whereas the eastern plunge underwent counterclockwise rotation. Deflections in shortening directions were partly related to basement heterogeneities, including weak supracrustal belts on the arch flanks, a strong granitic core, and local reactivation of Precambrian shear zones.
DS1992-1723
1992
Yonkee, W.A.Yonkee, W.A.Basement cover relations, Sevier orogenic belt, northern UtahGeological Society of America (GSA) Bulletin, Vol. 104, No. 3, March pp. 280-302UtahStructure, Sevier orogeny
DS200612-0207
2006
Yonsheng, D.Cai, L., Qingguo, Z., Yonsheng, D., Xiaopeng, H.Discovery of eclogite and its geological significance in Qiantang central Tibet.Chinese Science Bulletin, Vol. 51, 9, May pp. 1095-1100.China, TibetEclogite, tectonics
DS200612-1206
2006
YooSakai, T., Kondo, T., Ohtani, E., Terasaki, H., Miyahara, Yoo, Endo, Kuba, Suzuki, KikegawaWetting property at the core mantle boundary and core signature in plume source region.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p. 129.MantleGeophysics - seismics
DS202204-0546
2022
Yoo, K.Yoo, K., Park, I. Recovery of rare earth metals from nickel metal hydride batteries of electric vehicles.MDPI, Vol. 12, 1 , 11p.GlobalREE

Abstract: Nickel metal hydride (NiMH) batteries are extensively used in the manufacturing of portable electronic devices as well as electric vehicles due to their specific properties including high energy density, precise volume, resistance to overcharge, etc. These NiMH batteries contain significant amounts of rare earth metals (REMs) along with Co and Ni which are discarded due to illegal dumping and improper recycling practices. In view of their strategic, economic, and industrial importance, and to mitigate the demand and supply gap of REMs and the limited availability of natural resources, it is necessary to explore secondary resources of REMs. Therefore, the present paper reports a feasible hydrometallurgical process flowsheet for the recovery of REMs and valuable metals from spent NiMH batteries. More than 90% dissolution of REMs (Nd, Ce and La) was achieved using 2 M H2SO4 at 75 C in 60 min in the presence of 10% H2O2 (v/v). From the obtained leach liquor, the REMs, such as Nd and Ce, were recovered using 10% PC88A diluted in kerosene at eq. pH 1.5 and O/A ratio 1/1 in two stages of counter current extraction. La of 99% purity was selectively precipitated from the leach liquor in the pH range of 1.5 to 2.0, leaving Cu, Ni and Co in the filtrate. Further, Cu and Ni were extracted with LIX 84 at equilibrium pH 2.5 and 5, leaving Co in the raffinate. The developed process flow sheet is feasible and has potential for industrial exploitation after scale-up/pilot trails.
DS1991-1913
1991
Yoos, T.R.Yoos, T.R., Potter, C.J., Thigpen, J.L., Brown, L.D.The Cordilleran foreland thrust belt in northwestern Montana and northern Idaho from COCORP and industry seismic reflection dataAmerican Association Petrol. Geol, Vol. 75, No. 6, June pp. 1089-1106Montana, IdahoGeophysics -seismics, Tectonics
DS1989-0457
1989
Yorath, C.J.Gabrielse, H., Yorath, C.J.DNAG # 4. The Cordilleran orogen in CanadaGeoscience Canada, Vol. 16, No. 2, June pp. 67-83CordilleraTectonics-orogeny, Overview
DS1991-0523
1991
Yorath, C.J.Gabrielse, H., Yorath, C.J.Geology of the Cordilleran orogen in Canada. Part of DNAG series.Extracted pages from listing in the index under kimberlite and diatremeGeological Survey of Canada, Vol. 4, pp. 460, 461, 464, 465, 494, 495British ColumbiaBrief overview, Diatreme, kimberlite
DS1991-0524
1991
Yorath, C.J.Gabrielse, H., Yorath, C.J.Geology of the Cordilleran Orogen in Canada. DNAG volume seriesGeological Survey of Canada Geology of Canada DNAG series, No. 4, 840p. $ 80.00British Columbia, CordilleraRegional geology, Table of contents
DS1960-0828
1967
Yorck, D.Gittins, J.G., Macintyre, R.M., Yorck, D.The Ages of Carbonatite Complexes in Eastern CanadaCanadian Journal of Earth Sciences, Vol. 4, PP. 651-655.Canada, QuebecRelated Rocks
DS1985-0261
1985
York, D.Hanes, J.A., York, D., Hall, C.M.An 40 Ar-39 Ar geochronological and electron microprobe investigation of an Archean pyroxenite and its bearing on ancient atmospheric compositions.Canadian Journal of Earth Sciences, Vol. 22, pp. 947-58.MantleUltramafic Rocks - Not Specific To Diamonds, Argon, Geochronology
DS1989-0857
1989
York, D.Layer, P.W., Kroner, A., Mcwilliams, M., York, D.Elements of the Archean thermal history and apparent polar wander of the eastern Kaapvaal craton, Swaziland, from single grain dating andPaleomagnetismEarth and Planetary Science Letters, Vol. 93, No. 1, May pp. 23-34GlobalGeochronology
DS1990-0950
1990
York, D.Lopez Martinez, M., York, D.A comparative 40 Ar-39 Ar study of the Kapuskasing structural zone and the Wawa gneiss terrane: thermal and tectonic implicationsCanadian Journal of Earth Sciences, Vol. 27, No. 6, June pp. 787-793OntarioTectonics, Geochronology, Argon, Kapuskasing structural zo
DS1990-0951
1990
York, D.Lopez Martinez, M., York, D.A comparative 40Ar /39Ar study of the Kapuskasing structural zone and the Wawa gneiss terrane: thermal and tectonic implicationsCanadian Journal of Earth Sciences, Vol. 27, No. 6, June pp. 787-793OntarioTectonics, Wawa gneiss terrane
DS1992-0917
1992
York, D.Layer, P.W., Kroner, A., York, D.Pre-3000 Ma thermal history of the Archean Kaap Valley pluton, SouthAfricaGeology, Vol. 20, No. 8, August pp. 717-720South AfricaGeochronology, Barberton greenstone belt
DS1992-0960
1992
York, D.Lopez-Martinez, M., York, D., Hanes, J.A.A 40 Ar/39Ar geochronological study of komatiites and komatiitic basalts from the Lower On verwacht Volcanics: Barberton Mountainland, South AfricaPrecambrian Research, Vol. 57, No. 1-2, June pp. 91-120South AfricaKomatiites, Geochronology, Argon
DS1993-1802
1993
York, D.York, D.The earliest history of the earthScientific American, Vol. 268, No. 1, January pp. 90-96GlobalCrust, Geochronology
DS1997-1283
1997
York, D.York, D.A delightful dip for debunkers in search of lost timeInstitute Physics Publishing, Bristol, $ 20.00GlobalBook - review, Radiometric dating techniques
DS1970-0858
1973
York, YU.YU.York, YU.YU., Kashkarov, I.F., Polkanov, YU.A., Eremenko, G.K.Small (sand Size) Diamonds of the UkraineKiev: Izdat Naikova Dumka., 167P.Russia, UkraineKimberlite, Diamond, Kimberley
DS201805-0968
2018
Yoshiasa, A.Ono, K., Harada, Y., Yoneda, A., Yamamoto, J., Yoshiasa, A., Sugiyama, K., Arima, H., Watanabe, T.Determination of elastic constants of single crystal chromian spinel by resonant ultrasound spectroscopy and implications for fluid inclusion geobarometry.Physics and Chemistry of Minerals, Vol. 45, 3, pp. 237-247.Technologyxenolths

Abstract: We determined elastic constants of a single-crystal chromian spinel at temperatures from ?15 to 45 °C through the Rectangular Parallelepiped Resonance method. The sample is a natural chromian spinel, which was separated from a mantle xenolith. Elastic constants at an ambient temperature (T = 24.0 °C) are C 11 = 264.8(1.7) GPa, C 12 = 154.5(1.8) GPa and C 44 = 142.6(0.3) GPa. All the elastic constants decrease linearly with increasing temperature. The temperature derivatives are dC 11/dT = ?0.049(2) GPa/°K, dC 12/dT = ?0.019(1) GPa/°K and dC 44/dT = ?0.020(1) GPa/°K. As an implication of the elastic constants, we applied them to the correction of a fluid inclusion geobarometry, which utilizes residual pressure of fluid inclusion as a depth scale. Before entrainment by a magma, the fluid inclusions must have the identical fluid density in constituent minerals of a xenolith. It has been, however, pointed out that fluid density of fluid inclusions significantly varies with host mineral species. The present study elucidates that elastic constants and thermal expansion coefficients cannot explain the difference in fluid density among mineral species. The density difference would reflect the difference in the degree of plastic deformation in the minerals.
DS202008-1428
2020
Yoshiasa, A.Nishiyama, T., Ohfuji, H., Fukuba, K., Terauchi, M., Nishi, U., Harada, K., Unoki, K., Moribe, Y., Yoshiasa, A., Ishimaru, S., Mori, Y., Shigeno, M., Arai, S.Microdiamond in a low grade metapelite from a Cretaceous subduction complex, western Kyushu, Japan. ( UHP) Nishisonogi unitNature Scientific Reports, Vol. 10, 11645 11p. PdfAsia, Japanmicrodiamond

Abstract: Microdiamonds in metamorphic rocks are a signature of ultrahigh-pressure (UHP) metamorphism that occurs mostly at continental collision zones. Most UHP minerals, except coesite and microdiamond, have been partially or completely retrogressed during exhumation; therefore, the discovery of coesite and microdiamond is crucial to identify UHP metamorphism and to understand the tectonic history of metamorphic rocks. Microdiamonds typically occur as inclusions in minerals such as garnet. Here we report the discovery of microdiamond aggregates in the matrix of a metapelite from the Nishisonogi unit, Nagasaki Metamorphic Complex, western Kyushu, Japan. The Nishisonogi unit represents a Cretaceous subduction complex which has been considered as an epidote-blueschist subfacies metamorphic unit, and the metapelite is a member of a serpentinite mélange in the Nishisonogi unit. The temperature condition for the Nishisonogi unit is 450 °C, based on the Raman micro-spectroscopy of graphite. The coexistence of microdiamond and Mg-carbonates suggests the precipitation of microdiamond from C-O-H fluid under pressures higher than 2.8 GPa. This is the first report of metamorphic microdiamond from Japan, which reveals the hidden UHP history of the Nishisonogi unit. The tectonic evolution of Kyushu in the Japanese Archipelago should be reconsidered based on this finding.
DS201412-0403
2014
Yoshida, H.Imada, S., Ohta, K., Yagi, T., Hirose, K., Yoshida, H., Nagahara, H.Measurements of lattice thermal conductivity of MgO to core-mantle boundary.Geophysical Research Letters, Vol. 41, 13, pp. 4542-4547.MantleGeothermometry
DS1989-0255
1989
Yoshida, I.Chen Chia Fu, Huang, Yen.C., Hosomi, S., Yoshida, I.Effect of oxygen addition on microwave plasma CVD of diamond from CH4-H2mixtureMater. Res. Bulletin, Vol. 24, pp. 87-94GlobalDiamond synthesis
DS1999-0820
1999
Yoshida, K.Yoshimoto, M., Yoshida, K., Rachibana, T.Epitaxial diamond growth on sapphire in an oxidizing environmentNature, Vol. 399, No. 6734, May 27, pp. 340-341.GlobalDiamond - morphology
DS201312-0436
2013
Yoshida, K.Janak, M., Krogh Ravna, E.J., Kullerud, K., Yoshida, K., Milovsky, R., Hirajima, T.Discovery of diamond in the Tromso Nappe, Scandinavian Caledonides ( N. Norway).Journal of Metamorphic Geology, Vol. 31, 6, pp. 691-703.Europe, NorwayMicrodiamonds in gneiss
DS201502-0076
2014
Yoshida, K.Majka, J., Rosen, A., Janak, M., Froitzheim, N., Klonowska, I., Manecki, M., Sasinkova, V., Yoshida, K.Microdiamond discovered in the Seve Nappe ( Scandinavian Caledonides) and its exhumation by the "vacuum-cleaner" mechanism.Geology, Vol. 42, 12, pp. 1107-1110.Europe, SwedenSubduction, microdiamond
DS201504-0203
2015
Yoshida, K.Janak, M., Froitzheim, N., Yoshida, K., Sasinkova, V., Nosko, M., Kobayashi,T., Hirajima, T., Vrabec, M.Diamond in metasedimentary crustal rocks from Pohorje, eastern Alps: a window to deep continental subductionJournal of Metamorphic Geology, Vol. 33, 5, pp. 495-512.Europe, SloveniaSubduction
DS201505-0237
2014
Yoshida, K.Majka, J., Rosen, A., Janak, M., Froitzheim, N., Klonowska, I., Maneck, M., Sasinkova, V., Yoshida, K.Microdiamond discovered in the Seve Nappe (Scandinavian Caledonides) and its exhumation by the "vacuum-cleaner" mechanism.Geology, Vol. 42, 12, pp. 1107-110.EuropeMicrodiamonds
DS201602-0230
2016
Yoshida, K.Petrik, I., Janak, M., Froitzheim, N., Georgiev, N., Yoshida, K., Sasinkova, V., Konecny, P., Milovska, S.Triassic to Early Jurassic (c.200 Ma) UHP metamorphism in the Central Rhodopes: evidence from U-Pb-Th dating of monazite in diamond bearing gneiss from Chelelpare, Bulgaria.Journal of Metamorphic Geology, in press available, 44p.Europe, BulgariaGneiss - diamonds

Abstract: Evidence for ultrahigh-pressure metamorphism (UHPM) in the Rhodope Metamorphic Complex comes from occurrence of diamond in pelitic gneisses, variably overprinted by granulite facies metamorphism, known from several areas of the Rhodopes. However, tectonic setting and timing of UHPM are not interpreted unanimously. Linking age to metamorphic stage is a prerequisite for reconstruction of these processes. Here we use monazite in diamond-bearing gneiss from Chepelare (Bulgaria) to date the diamond-forming UHPM event in the Central Rhodopes. The diamond-bearing gneiss comes from a strongly deformed, lithologically heterogeneous zone (Chepelare Mélange) sandwiched between two migmatized orthogneiss units, known as Arda-I and Arda-II. Diamond, identified by Raman micro-spectroscopy, shows the characteristic band mostly centred between 1332 and 1330 cm?1. The microdiamond occurs as single grains or polyphase diamond + carbonate inclusions, rarely with CO2. Thermodynamic modelling shows that garnet was stable at UHP conditions of 3.5-4.6 GPa and 700-800 °C, in the stability field of diamond, and was re-equilibrated at granulite facies/partial melting conditions of 0.8-1.2 GPa and 750-800 °C. The texture of monazite shows older central parts and extensive younger domains which formed due to metasomatic replacement in solid residue and/or overgrowth in melt domains. The monazite core compositions, with distinctly lower Y, Th and U contents, suggest its formation in equilibrium with garnet. The U-Th-Pb dating of monazite using electron microprobe analysis yielded a c. 200 Ma age for the older cores with low Th, Y, U and high La/Nd ratio, and a c. 160 Ma age for the dominant younger monazite enriched in Th, Y, U and HREE. The older age of around 200 Ma is interpreted as the timing of UHPM whereas the younger age of around 160 Ma as granulite facies/partial melting overprint. Our results suggest that UHPM occurred in Late Triassic to Early Jurassic time, in the framework of collision and subduction of continental crust after the closure of Palaeotethys.
DS201604-0621
2016
Yoshida, K.Petrik, I., Janak, M., Froitzheim, N., Georgiev, N., Yoshida, K., Sasinkova, V., Konecny, P., Milovska, S.Triassic to Early Jurassic ( c. 200Ma) UHP metamorphism in the Central Rhodopes: evidence from U-Pb dating of monazite in diamond bearing gneiss from Chepelare ( Bulgaria).Journal of Metamorphic Geology, Vol. 34, 3, pp. 265-291.Europe, BulgariaUHP diamond bearing gneiss
DS201606-1105
2016
Yoshida, K.Petrik, I., Janak, M., Froitzheim, N., Georgiev, N., Yoshida, K., Sasinkova, V., Konecny, P., Milovska, S.Triassic to Early Jurassic ( c. 200Ma) UHP metamorphism in the central Rhodopes: evidence from U-Pb-Th dating of monazite in diamond bearing gneiss from Chepelare Bulgaria.Journal of Metamorphic Geology, Vol. 34, 3, pp. 265-291.Europe, BulgariaDiamonds in gneiss
DS201802-0218
2018
Yoshida, K.Akaogi, M., Kawahara, A., Kojitani, H., Yoshida, K., Anegawa, Y., Ishii, T.High pressure phase transitions in MgCr2O4 MgSiO4 composition: reactions between olivine and chromite with implications for ultrahigh pressure chromitites.American Mineralogist, Vol. 103, pp. 161-170.Mantlechromites
DS1996-1580
1996
Yoshida, M.Yoshida, M., Bindu, R.S., et al.Geochronologic constraints of granulite terranes of South India and their implications for Precambrian...Journal of Southeast Asian Sciences, Vol. 14, No. 3-4, pp. 137-147IndiaGeochronology
DS2002-1763
2002
Yoshida, M.Yoshida, M., Dashupta, S.Proterozoic evolution of the northeastern Canadian Shield: lithoprobe eastern Canadian shield onshore-offshore transect ECSOOT - summary.Geological Society of London (U.K.), 440p.$ 183.00 http://bookshop.geolsoc.org.ukGondwanaBook - geology, tectonics
DS2003-1532
2003
Yoshida, M.Yoshida, M., Windley, B.F., Dasgupta, S.Proterozoic East Gondwana: supercontinent assembly and breakupGeological Society of London, Special Publication, No. 206, 472p. $ 183. http://bookshop.geolsoc.org.ukGondwana, RodiniaBook
DS2003-1533
2003
Yoshida, M.Yoshida, M., Windley, B.F., Dasgupta, S.Proterozoic East Gondwana: super continent assembly and break-upGeological Society of London Special Paper, No. 206, 440p. $280. www.geosoc.orgRodinia, review, Book
DS200412-2185
2003
Yoshida, M.Yoshida, M., Jacobs, J., Santosh, M., Rajesh, H.M.Role of Pan African events in the Circum East Antarctic Orogen of East Gondwana: a critical overview.Proterozoic East Gondwana: Supercontinent assembly and Breakup. Ed. Yoshida , Geological Society of London Spe, No. 206, pp. 57-76.AntarcticaPlume, tectonics
DS200412-2186
2004
Yoshida, M.Yoshida, M., Ogawa, M.The role of hot uprising plumes in the initiation of plate like regime of three dimensional mantle convection.Geophysical Research Letters, Vol. 31, 5, March 16, DOI 10.1029/2003 GLO17376MantleHotspots
DS200412-2187
2003
Yoshida, M.Yoshida, M., Windley, B.F., Dasgupta, S.Proterozoic East Gondwana: supercontinent assembly and breakup.Geological Society of London, Special Publication, No. 206, 472p. $ 183. http://bookshop.geolsoc.org.ukGondwana, RodiniaTectonics - evolution Book
DS200512-1220
2004
Yoshida, M.Yoshida, M.Influence of two major phase transitions on mantle convection with moving and subducting plates.Earth Planets and Space, Vol. 56, 11, pp.1019-1033.MantleConvection
DS200612-1574
2006
Yoshida, M.Yoshida, M., Kageyama, A.Low degree mantle convection with strongly temperature and depth dependent viscosity in a three dimensional spherical shell.Journal of Geophysical Reesarch, Vol. 111, B3, B03412MantleGeophysics - seismics, convection
DS200612-1575
2005
Yoshida, M.Yoshida, M., Ogawa, M.Plume heat flow in a numerical model of mantle convection with moving plates.Earth and Planetary Science Letters, Vol. 239, 3-4, pp. 276-285.MantleConvection
DS201012-0876
2010
Yoshida, M.Yoshida, M.Preliminary three dimensional model of mantle convection with deformable, mobile continental lithosphere.Earth and Planetary Science Letters, Vol. 295, 1-2, pp. 205-218.MantleConvection
DS201012-0877
2010
Yoshida, M.Yoshida, M.Temporal evolution of the stress state in a supercontinent during mantle reorganization.Geophysical Journal International, Vol. 180, 1, pp. 1-22.MantleGeodynamics
DS201112-1141
2011
Yoshida, M.Yoshida, M., Santosh, M.Future supercontinent assembled in the northern hemisphere.Terra Nova, Vol. 23. 5, pp. 283-348.MantleConvection, density anomaly
DS201112-1142
2011
Yoshida, M.Yoshida, M., Santosh, M.Supercontinents, mantle dynamics and plate tectonics: a perspective based on conceptual vs. numerical models.Earth Science Reviews, Vol. 105, 1-2, pp. 1-24.MantleGeodynamics
DS201112-1143
2011
Yoshida, M.Yoshida, M., Santosh, M.Future supercontinent assembled in the northern hemisphere.Terra Nova, Vol. 23, 5, pp. 333-338.MantleGondwana
DS201212-0807
2012
Yoshida, M.Yoshida, M.Dynamic role of the rheological contrast between cratonic and oceanic lithospheres in the longevity of cratonic lithosphere: a three dimensional numerical study.Tectonophysics, Vol. 532-535, pp. 156-166.MantleConvection
DS201212-0808
2012
Yoshida, M.Yoshida, M., Tajima, F., Honda, S., Morishige, M.The 3D numerical modeling of subduction dynamics: plate stagnation and segmentation, and crustal advection in the wet mantle transition zone.Journal of Geophysical Research, Vol. 117, B4, B0104MantleSubduction
DS201312-0996
2013
Yoshida, M.Yoshida, M.The role of harzburgite layers in the morphology of subducting plates and behavior of oceanic crustal layers.Geophysical Research Letters, Vol. 40, 20, pp. 5387-5392.MantleSubduction
DS201312-0997
2013
Yoshida, M.Yoshida, M., Santosh, M.Mantle convection modeling of the the supercontinent cycle: introversion, extroversion or a combination?Geoscience Frontiers, in press availableMantleConvection
DS201412-1010
2014
Yoshida, M.Yoshida, M.A new conceptual model for whole mantle convection and the origin of hotspot plumes.Journal of Geodynamics, Vol. 78, pp. 32-41.MantleConvection
DS201610-1920
2016
Yoshida, M.Yoshida, M.Formation of a future supercontinent through plat motion-driven flow coupled with mantle downwellng flow.Geology, Vol. 44, 9, pp. 755-758.MantleCycles, convection

Abstract: Series of high-resolution numerical simulations of three-dimensional mantle convection were performed to examine the interaction between the drifting continental lithospheres and the underlying mantle structure for 250 m.y. from the present, and to predict the configuration of the future supercontinent. The density anomaly of the mantle interior was determined by the seismic velocity anomaly from global seismic tomography data sets, which contain well-resolved subducting slabs. The present-day plate motion was imposed for the first stage of the simulation as a velocity boundary condition at the top surface boundary, instead of a shear stress-free condition. The switching time from the plate motion boundary to shear stress-free conditions was taken as a free parameter. The results revealed that Australia, Eurasia, North America, and Africa will merge together in the Northern Hemisphere to form a new supercontinent within ?250 m.y. from the present. The continental drift was assumed to be realized by plate-scale mantle flow, rather than large-scale upwelling plumes. That is, continuously moving plates at the surface for the first stage of the simulation are mechanically coupled with the subducting slabs in the mantle; this enhances the underlying mantle downwelling flow. As a result, persistent continental drift can be reproduced for long future time periods even though top surface boundary conditions may switch in response to shear stress-free conditions. The configuration of the numerically reproduced future supercontinent in this study is broadly consistent with the hypothetical model of Amasia as indicated by previous findings from geological correlations and a paleogeographic reconstruction.
DS201904-0801
2019
Yoshida, M.Yoshida, M.On mantle drag force for the formation of a next supercontinent as estimated from a numerical simulation model of global mantle convection.Terra Nova, Vol. 31, 2, pp. 135-149.Mantleconvection

Abstract: Three?dimensional spherical mantle convection was simulated to predict future continental motion and investigate the driving force of continental motion. Results show that both the time required (?300 Ma from the present) and the process for the next supercontinent formation are sensitive to the choice of critical rheological parameters for mantle dynamics, such as a viscosity contrast between the upper and lower mantles and a yield strength of the lithosphere. From all the numerical models studied herein, mantle drag force by horizontal mantle flow beneath the continents may mostly act as a resistance force for the continental motion in the process of forming a new supercontinent. The maximum absolute magnitude of the tensional and compressional stress acting at the base of the moving continents is in the order of 100 MPa, which is comparable to a typical value of the slab pull force.
DS202007-1186
2020
Yoshida, M.Yoshida, M., Saito, S., Yoshozawa, K.Possible tectonic patterns along the eastern margin of Gondwanaland from numerical studies of mantle convection.Tectonophysics, Vol. 787, 228476, 12p. PdfMantleconvection

Abstract: Two end-member scenarios have been proposed for the tectonic situation along the eastern margins of Gondwanaland before Zealandia was formed ca. 100 million years ago (Ma), namely: (1) A subduction zone located far from the eastern margin of Zealandia, wherein Zealandia may have separated from Gondwanaland by plume push of an active hotspot plume.; (2) A subduction zone located along the eastern margin of Gondwanaland, wherein Zealandia possibly separated from Gondwanaland via trench/subduction retreat. Assuming that the thermal structure of the deep mantle and source of hotspot plumes remained relatively stationary over the last hundred million years, major hotspot plumes with a large buoyancy flux did not exist under Zealandia; the eastern margins of Gondwanaland were far from two large low-shear-velocity provinces under the Africa-Atlantic and South Pacific regions. Herein, through numerical studies of three-dimensional global mantle convection, we examined the mantle convection and surface tectonic patterns at ~100 Ma. The present model considered the real configuration of Gondwanaland at the model surface to observe long-term variations of mantle convection and the resulting surface tectonic conditions. The results demonstrate that the extensive subduction zones developed preferentially along the eastern margin of Gondwanaland when the temperature anomaly of the lower mantle was primarily dominated by high-temperature regions under present-day Africa-Atlantic and South Pacific regions. The results of this study support one of the proposed hypotheses, where the breakup at the eastern margins of Gondwanaland at ~100 Ma occurred via trench/subduction retreat.
DS202105-0801
2021
Yoshida, M.Yoshida, M., Yoshizawa, K.Continental drift with deep cratonic roots.Annual Review of Earth Planetary Sciences, Vol. 49, pp. 117-139.Mantletectonics

Abstract: The influence of the continental lithosphere and its root (or keel) on the continental drift of Earth is a key element in the history of plate tectonics. Previous geodynamic studies of mantle flow suggested that the cratonic root is moderately mechanically coupled with the underlying mantle, and stable continental drift on Earth's timescales occurs when the effective viscosity contrast between the continental lithosphere and the underlying mantle is approximately 103. Both geodynamics and seismological studies indicate that mechanically weak mobile belts (i.e., orogenic or suture zones) that surround cratons may play a role in the longevity of the cratonic lithosphere over geologically long timescales (i.e., over 1,000 million years) because they act as a buffer region against the high-viscosity cratons. Low-viscosity asthenosphere, characterized by slow seismic velocities, reduces the basal drag force acting on the cratonic root, which may also contribute to the longevity of the cratonic lithosphere.
DS202107-1146
2021
Yoshida, M.Yoshida, M., Yoshizawa, K.Continental drift with deep cratonic roots.Annual Review of Earth and Planetary Sciences, Vol. 49, pp. 117-139.Mantlecratons

Abstract: The influence of the continental lithosphere and its root (or keel) on the continental drift of Earth is a key element in the history of plate tectonics. Previous geodynamic studies of mantle flow suggested that the cratonic root is moderately mechanically coupled with the underlying mantle, and stable continental drift on Earth's timescales occurs when the effective viscosity contrast between the continental lithosphere and the underlying mantle is approximately 103. Both geodynamics and seismological studies indicate that mechanically weak mobile belts (i.e., orogenic or suture zones) that surround cratons may play a role in the longevity of the cratonic lithosphere over geologically long timescales (i.e., over 1,000 million years) because they act as a buffer region against the high-viscosity cratons. Low-viscosity asthenosphere, characterized by slow seismic velocities, reduces the basal drag force acting on the cratonic root, which may also contribute to the longevity of the cratonic lithosphere. The role of the continental lithosphere and its root on the continental drift is reviewed from recent geodynamic and seismological studies. The cratonic root is moderately mechanically coupled with the underlying mantle and deformed by mantle flow over geological timescales. Orogenic belts or suture zones that surround cratons act as a buffer to protect cratons and are essential for their longevity. Low-viscosity asthenosphere may reduce the basal drag acting on the cratonic root and also contribute to its stability and longevity.
DS1994-0964
1994
Yoshida, S.Kumazawa, M., Yoshida, S., Ito, T., Yoshioka, H.Archean Proterozoic boundary interpreted as a catastrophic collapse of the stable density stratification in the core.Journal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 50-59.MantleBoundary, Tidal cycles
DS200612-1007
2005
Yoshida, S.Okamoto, T., Sumita, I., Nakakuki, T., Yoshida, S.Deformation of a partially molten D' layer by small scale convection and the resulting seismic anistrophy and ultralow velocity zone.Physics of the Earth and Planetary Interiors, Vol. 153, 1-3, pp. 32-48.MantleBoundary
DS1985-0021
1985
Yoshida, T.Aoki, K.I., Yoshida, T., Yusa, K., Nakamura, Y.Petrology and Geochemistry of the Nyamuragira Volcano, ZaireJournal of VOLCANOLOGY, Vol. 25, No. 1-2, JUNE PP. 1-28.Central Africa, ZairePetrology
DS1986-0888
1986
Yoshida, T.Yoshida, T., Aoki, K.I.Geochemistry of some continental basaltsThe Science reports of the Tohoku University, Third series, Vol. XVI No. 3, Dec. pp. 367-394United StatesMinette, Alkaline rocks
DS1995-0720
1995
Yoshida, T.Haimila, N., Yoshida, T.Assessment report on the Chain Lake Diamod claims in the Hanna areaAlberta Geological Survey, MIN 19950029AlbertaExploration - assessment
DS200512-0445
2005
Yoshida, T.Honda, S., Yoshida, T.Effects of oblique subduction on the 3-D pattern of small scale convection within the mantle wedge.Geophysical Research Letters, Vol. 32, 13, July 16, L13307MantleGeophysics - seismics, subduction
DS2001-1137
2001
Yoshihara, A.Sumita, I., Hatakeyama, T., Yoshihara, A., Hamano, Y.Paleomagnetism of late Archean rocks of Hamersley basin, western Australia and the paleointensity...Physics of the Earth and Planetary Interiors, Vol. 128, No. 1-4, Dec. 10, pp. 223-41.AustraliaPaleomagnetism, Early Proterozoic
DS2000-0512
2000
Yoshii, T.Koketsu, K., Yoshii, T.A seismicity database and interactive retrieval tool: SeisviewComp. and Geosc., Vol. 26, No. 7, pp. 839-46.GlobalComputer - database, Geophysics - seismics
DS1991-1759
1991
Yoshikawa, M.Tzeng, T., Yoshikawa, M., Murakawa, M., Feldman, A.Applications of diamond films and related materials. Proceedings of the 1st International conference held Auburn Al. USA August 17-22, 1991Elsevier -Material Science Monograph, Vol. 73, 900p. ISBN 0-444-89162-5, approx. $ 243.00 United StatesGlobalDiamond technology, Applications -CVD.
DS201012-0878
2010
Yoshikawa, M.Yoshikawa, M., Kawamoto, T., Shibata, T., Yamamoto, J.Geochemical and Sr Nd isotopic characteristics and pressure temperature estimates of mantle xenoliths from French Massif Central: metasomatism and carbonatites..Geological Society of London Special Publication, No. 337, pp. 153-175.Europe, FranceCarbonatite
DS201212-0287
2012
Yoshikawa, M.Harvey, J., Yoshikawa, M., Hammond, S.J., Burton, K.W.Deciphering the trace element characteristics in Kilbourne Hole peridotite xenoliths: melt-rock interaction and metasomatism beneath the Rio Grande rift, SW USA.Journal of Petrology, Vol. 53, 8, pp. 1709-1742.United StatesXenoliths
DS200612-0995
2006
Yoshimitsu, J.Obayashi, M., Sugioka, H., Yoshimitsu, J., Fukao, Y.High temperature anomalies oceanward of subducting slabs at the 410 km discontinuity.Earth and Planetary Science Letters, Vol. 243, 1-2, Mar 15, pp. 149-158.MantleSubduction
DS200912-0543
2009
Yoshimitsu, J.Obayashi, M., Yoshimitsu, J., Fukao, Y.Tearing of stagnant slab.Science, Vol. 324, 5931, pp. 1173-1175.JapanSubduction
DS201412-0644
2013
Yoshimitsu, J.Obayashi, M., Yoshimitsu, J., Noelt, G., Fukao, Y., Shiobara, H., Sugioka, H., Miyamachi, H., Gao, Y.Finite frequency whole mantle P wave tomography: improvement of subducted slab images.Geophysical Research Letters, Vol. 40, 21, pp. 5652-5657.MantleTomography
DS1999-0820
1999
Yoshimoto, M.Yoshimoto, M., Yoshida, K., Rachibana, T.Epitaxial diamond growth on sapphire in an oxidizing environmentNature, Vol. 399, No. 6734, May 27, pp. 340-341.GlobalDiamond - morphology
DS200812-1299
2008
Yoshina, T.Yoshina, T., Manthilake, G., Matsuzaki, T., Katsura, T.Dry mantle transition zone inferred from the conductivity of wadsleyite and ringwoodite.Nature, Vol. 451, 7176, pp. 326-329.MantleGeochemistry
DS2002-1188
2002
Yoshino, T.Ono, S., Mibe, K., Yoshino, T.Aqueous fluid connectivity in pyrope aggregates: water transport into the deep mantle by a subducted oceanic crust without any hydrous minerals.Earth and Planetary Science Letters, Vol. 203, 3-4, pp. 895-903.MantleSubduction - water
DS200412-2075
2004
Yoshino, T.Walter, M.J., Kubo, A., Yoshino, T., Brodholt, J., Koga, K.T., Ohishi, Y.Phase relations and equation of state aluminous Mg silicate perovskite and implications for Earth's lower mantle.Earth and Planetary Science Letters, Vol. 222, 2, pp. 501-516.MantlePerovskite
DS200612-1576
2005
Yoshino, T.Yoshino, T., Takei, Y., Wark, D.A., Watson, E.B.Grain boundary wetness of texturally equilibrated rocks, with implications for seismic properties of the upper mantle.Journal of Geophysical Research, Vol. 110, B8, B08205, 10.1029/2004 JB003544MantleGeophysics - seismic
DS200712-1206
2007
Yoshino, T.Yoshino, T., Nishihara, Y., Karato, S.Complete wetting of olivine grain boundaries by a hydrous melt near the mantle transition zone.Earth and Planetary Science Letters, Vol. 256, 3-4, pp. 466-472.MantleMelting
DS200712-1207
2007
Yoshino, T.Yoshino, T., Yamazaki, D.Grain growth kinetics of CalrO3 perovskite and post-perovskite, with implications for rheology of D' layer.Earth and Planetary Science Letters, Vol. 255, 3-4, March 30, pp. 485-493.MantleD layer
DS201012-0347
2009
Yoshino, T.Katsura, T., Yoshino, T., Manthilake, G., Matsuzaki, T.Electrical conductivity of the major upper mantle minerals: a review.Russian Geology and Geophysics, Vol. 50, 12, pp. 1139-1145.MantleGeophysics - seismics
DS201012-0879
2010
Yoshino, T.Yoshino, T.Laboratory electrical conductivity measurement of mantle minerals.Surveysin Geophysics, Vol. 31, pp. 163-206.MantleGeophysics -magnetotellurics
DS201012-0880
2010
Yoshino, T.Yoshino, T., Laumonier, M., McIssac, E., Katsura, T.Electrical conductivity of basaltic and carbonatite melt bearing peridotites at high pressures: implications for melt distribution and melt fractionEarth and Planetary Science Letters, Vol. 295, 3-4, pp. 593-602.MantleMelting - upper
DS201112-0916
2011
Yoshino, T.Satish-Kumar, M., So, H., Yoshino, T., Kato, M., Hiroi, Y.Experimental determination of carbon isotope fractionation between iron carbide melt and carbon: 12 C-enriched carbon in the Earth's core?Earth and Planetary Science Letters, Vol. 310, 3-4, pp. 340-348.MantleCarbon
DS201212-0809
2013
Yoshino, T.Yoshino, T., Katsura, T.Electrical conductivity of mantle minerals: role of water.Annual Review of Earth and Planetary Sciences, Vol. 41, available April 2013MantleHydrous mineralogy
DS201212-0811
2012
Yoshino, T.Zhang, B., Yoshino, T., Wu, X., Matsuzaki, T., Shan, S., Katsura, T.Electrical conductivity of enstatite as a function of water content: implications for the electrical structure in the upper mantle.Earth and Planetary Science Letters, Vol. 357-358, pp. 11-20.MantleHT Hp hydrous conditions
DS201312-0998
2013
Yoshino, T.Yoshino, T., Katsura, T.Electrical conductivity of mantle minerals: role of water in conductivity anomalies.Annual Review of Earth and Planetary Sciences, Vol. 41, pp. 605-628.MantleGeophysics - seismics
DS201412-0556
2014
Yoshino, T.Martirosyan, N., Yoshino, T., Shatskiy, A., Chanyshev, A., Litasov, K.Kenetic study of Ca- carbonate - iron interaction. ( global geodynamic processes - diamond formation)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. AbstractMantleGeodynamics
DS201412-0557
2014
Yoshino, T.Martirosyan, N., Yoshino, T., Shatskiy, A., Chanyshev, A., Litasov, K.Effect of water on the stability of magnesite in the mantle under reduced conditions.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. AbstractMantleWater
DS201607-1324
2016
Yoshino, T.Zhao, C., Yoshino, T.Electrical conductivity of mantle clinopyroxene as a function of water content and its implication on electrical structure of uppermost mantle.Earth and Planetary Science Letters, Vol. 447, pp. 1-9.MantleWater content

Abstract: The electrical conductivity of San Carlos clinopyroxene aggregates with various water contents were measured under Ni -NiO buffer at 1.5 GPa and 600 -1200 K in a DIA-type apparatus. The conductivity increases with increasing water content in clinopyroxene. Hidden conduction mechanism was detected because of the much smaller iron content in clinopyroxene, which was usually covered by small polaron conduction in other nominally anhydrous minerals. The identified activation enthalpies ranged from 0.70 -0.75 eV to 1.23 -1.37 eV. Our result reveals that the dominant charge-carrying species in electrical conductivity could change with temperature and water content. At high temperatures relevant to asthenospheric condition, activation enthalpy for the conductivity agrees well with that for the hydrogen self-diffusion. The dominant charge carrier therefore might be M site vacancy. However, contrary to previous view that all hydrogens contribute to increasing conductivity equally, our result shows that only a limited amount (20% -40%) of hydrogen acts as effective charge carrier in clinopyroxene. On the other hand, the activation enthalpy for the conductivity at low temperatures is significantly lower than that for the hydrogen self-diffusion, similar to what has been observed in olivine and orthopyroxene. This type of conduction is probably caused by fast diffusion of specific hydrogen or fast hydrogen grain boundary diffusion. At low temperatures, the proton conduction of clinopyroxene is nearly one order and two orders of magnitude lower than those of olivine and orthopyroxene, respectively, and tends to converge at high temperatures. Using the present data combined with conductivity of olivine and orthopyroxene, a laboratory-based conductivity-depth profile in the uppermost mantle shows that hydrous clinopyroxene cannot account for the high conductive regions observed beneath the ocean floor near Eastern Pacific Rise. The presence of partial melt would be unavoidable.
DS201610-1880
2016
Yoshino, T.Kondo, N., Yoshino, T., Matsukage, K., Kogiso, T.Major element composition in an early enriched reservoir: constarints from 142 Nd/144 Nd isotope systematics in the earth Earth and high pressure melting experiments of a primitive peridotite,Progress in Earth and Planetary Science, Vol. 3, 25, Aug. 22MantleExperimental petrology

Abstract: The Accessible Silicate Earth (ASE) has a higher 142Nd/144Nd ratio than most chondrites. Thus, if the Earth is assumed to have formed from these chondrites, a complement low-142Nd/144Nd reservoir is needed. Such a low-142Nd/144Nd reservoir is believed to have been derived from a melt in the early Earth and is called the Early Enriched Reservoir (EER). Although the major element composition of the EER is crucial for estimating its chemical and physical properties (e.g., density) and is also essential for understanding the origin and fate of the EER, which are both major factors that determine the present composition of the Earth, it has not yet been robustly established. In order to determine the major element composition of the EER, we estimated the age and pressure-temperature conditions to form the EER that would best explain its Nd isotopic characteristics, based on Sm-Nd partitioning and its dependence on pressure, temperature, and melting phase relations. Our estimate indicates that the EER formed within 33.5 Myr of Solar System formation and at near-solidus temperatures and shallow upper-mantle pressures. We then performed high-pressure melting experiments on primitive peridotite to determine the major element composition of the EER at estimated temperature at 7 GPa and calculated the density of the EER. The result of our experiments indicates that the near-solidus melt is iron-rich komatiite. The estimated density of the near-solidus melt is lower than that of the primitive peridotite, suggesting that the EER melt would have ascended in the mantle to form an early crust. Given that high mantle potential temperatures are assumed to have existed in the Hadean, it follows that the EER melt was generated at high pressure and, therefore, its composition would have been picritic to komatiitic. As the formation age of the EER estimated in our study precedes the last giant, lunar-forming impact, the picritic to komatiitic crust (EER) would most likely have been ejected from the Earth by the last giant impact or preceding impacts. Thus, the EER has been lost, leaving the Earth more depleted than its original composition.
DS201902-0296
2019
Yoshino, T.Martirosyan, N.S., Shatskiy, A., Chanyshev, A.D., Litasov, K.D., Yoshino, T.Effect of water on the magnesium iron interaction, with implications for the fate of carbonates in the deep mantleLithos, Vol. 326-327, pp. 572-585.Mantlewater
DS201903-0531
2019
Yoshino, T.Martirosayan, N.S., Shatskiy, A., Chanyshev, A.D., Litasov, K.D., Podborodnikov, I.V., Yoshino, T.Effect of water on the magnesite-iron interaction, with implications for the fate of carbonates in the deep mantle.Lithos, Vol. 326-327, pp. 435-445.Mantleperidotite

Abstract: The subduction of carbonates beyond 250-300?km, where redox conditions favour the presence of metallic iron (Fe), will result in redox reactions with the Fe dispersed in the silicate rocks. Here, we studied the effect of water on the carbonate-Fe interaction in the hydromagnesite-Fe system at 6, 8 and 16?GPa and the peridotite-CO2-H2O-Fe system at 8?GPa, using a multianvil apparatus. In all of the studied samples, we observed the formation of magnesiowüstite, graphite and carbide. Additionally, in the peridotite-CO2-H2O-Fe system, magnesiowüstite reacted with pyroxenes, resulting in olivine enrichment. Kinetic calculations performed at 8?GPa showed that, at the pressure-temperature (P-T) parameters of the ‘hot’, ‘medium’ and ‘cold’ subduction, about 40, 12 and 4?vol% of carbonates, respectively, would be reduced in the hydrous system within 1 Myr, assuming direct contact with Fe. Based on the present results, it is suggested that carbonates will largely be consumed during the characteristic subduction time to the mantle transition zone by reaction with the reduced mantle in the presence of hydrous fluid.
DS1994-0964
1994
Yoshioka, H.Kumazawa, M., Yoshida, S., Ito, T., Yoshioka, H.Archean Proterozoic boundary interpreted as a catastrophic collapse of the stable density stratification in the core.Journal of the Geological Society of Japan, Vol. 100, No. 1, January pp. 50-59.MantleBoundary, Tidal cycles
DS200412-1716
2004
Yoshioka, N.Sachan, H.K., Mukherjee, B.K., Ogasawara, Y., Mauyama, S., Ishida, H., Muko, A., Yoshioka, N.Discovery of coesite from Indus Suture Zone (ISZ) Ladakh India: evidence for deep subduction.European Journal of Mineralogy, Vol. 16, 2, pp. 235-240.IndiaSubduction
DS200512-1221
2005
Yoshioka, N.Yoshioka, N., Ogasawara, Y.Cathodluminesence of microdiamond in dolomite marble from the Kokchetav massif - additional evidence for two stage growth in diamond.International Geology Review, Vol. 47, 7, pp. 703-715.RussiaMicrodiamonds
DS2001-0817
2001
Yoshioka, S.Murakami, T., Yoshioka, S.The relationship between the physical properties of the assumed pyrolite composition and depth distributionsPhysical Earth and Planetary Interiors, Vol. 125, No. 1-4, pp. 1-17.MantleGeophysics - seismics
DS200812-1181
2007
Yoshioka, S.Torii, Y., Yoshioka, S.Physical conditions producing slab stagnation: constraints of the Clapeyron slope, mantle viscosity retreat and dip angles.Tectonophysics, Vol. 445, 3-4, pp. 200-209.MantleSlab
DS1988-0777
1988
Yoshioka, T.Yoshioka, T., Imai, O., Ohara, H., Doi, A., Fujimori, N.Thin solid films of ceramic and diamond and their applicationSurf. Coat. Technol, Vol. 36, No. 1-2, pp. 311-318GlobalDiamond applications/coatings
DS201804-0754
2018
Yoshioka, T.Yoshioka, T., Wiedenbeck, M., Shcheka, S., Keppler, H.Nitrogen solubility in the deep mantle and the origin of Earth's primordial nitrogen budget.Earth and Planteray Science Letters, Vol. 488, pp. 134-143.Mantlenitrogen

Abstract: The solubility of nitrogen in the major minerals of the Earth's transition zone and lower mantle (wadsleyite, ringwoodite, bridgmanite, and Ca-silicate perovskite) coexisting with a reduced, nitrogen-rich fluid phase was measured. Experiments were carried out in multi-anvil presses at 14 to 24 GPa and 1100 to 1800?°C close to the Fe-FeO buffer. Starting materials were enriched in 15N and the nitrogen concentrations in run products were measured by secondary ion mass spectrometry. Observed nitrogen (15N) solubilities in wadsleyite and ringwoodite typically range from 10 to 250 ?g/g and strongly increase with temperature. Nitrogen solubility in bridgmanite is about 20 ?g/g, while Ca-silicate perovskite incorporates about 30 ?g/g under comparable conditions. Partition coefficients of nitrogen derived from coexisting phases are DNwadsleyite/olivine = 5.1 ± 2.1, DNringwoodite/wadsleyite = 0.49 ± 0.29, and DNbridgmanite/ringwoodite = 0.24 . Nitrogen solubility in the solid, iron-rich metal phase coexisting with the silicates was also measured and reached a maximum of nearly 1 wt.% 15N at 23 GPa and 1400?°C. These data yield a partition coefficient of nitrogen between iron metal and bridgmanite of DNmetal/bridgmanite???98, implying that in a lower mantle containing about 1% of iron metal, about half of the nitrogen still resides in the silicates. The high nitrogen solubility in wadsleyite and ringwoodite may be responsible for the low nitrogen concentrations often observed in ultradeep diamonds from the transition zone. Overall, the solubility data suggest that the transition zone and the lower mantle have the capacity to store at least 33 times the mass of nitrogen presently residing in the atmosphere. By combining the nitrogen solubility data in minerals with data on nitrogen solubility in silicate melts, mineral/melt partition coefficients of nitrogen can be estimated, from which the behavior of nitrogen during magma ocean crystallization can be modeled. Such models show that if the magma ocean coexisted with a primordial atmosphere having a nitrogen partial pressure of just a few bars, several times the current atmospheric mass of nitrogen must have been trapped in the deep mantle. It is therefore plausible that the apparent depletion of nitrogen relative to other volatiles in the near-surface reservoirs reflects the storage of a larger reservoir of nitrogen in the solid Earth. Dynamic exchange between these reservoirs may have induced major fluctuations of bulk atmospheric pressure over Earth's history.
DS200512-0348
2005
Yoshizawa, K.Goes, S., Simons, F.J., Yoshizawa, K.Seismic constraints on temperature of the Australian upper mantle.Earth and Planetary Science Letters, Vol. 236, 1-2, pp. 227-237.AustraliaGeophysics - seismics
DS200812-0354
2008
Yoshizawa, K.Fishwick, S., Heintz, M., Kennett, B.L.N., Reading, A.M., Yoshizawa, K.Steps in lithospheric thickness within eastern Australia, evidence from surface wave tomography.Tectonics, Vol. 27, TC 4009AustraliaTomography
DS202105-0801
2021
Yoshizawa, K.Yoshida, M., Yoshizawa, K.Continental drift with deep cratonic roots.Annual Review of Earth Planetary Sciences, Vol. 49, pp. 117-139.Mantletectonics

Abstract: The influence of the continental lithosphere and its root (or keel) on the continental drift of Earth is a key element in the history of plate tectonics. Previous geodynamic studies of mantle flow suggested that the cratonic root is moderately mechanically coupled with the underlying mantle, and stable continental drift on Earth's timescales occurs when the effective viscosity contrast between the continental lithosphere and the underlying mantle is approximately 103. Both geodynamics and seismological studies indicate that mechanically weak mobile belts (i.e., orogenic or suture zones) that surround cratons may play a role in the longevity of the cratonic lithosphere over geologically long timescales (i.e., over 1,000 million years) because they act as a buffer region against the high-viscosity cratons. Low-viscosity asthenosphere, characterized by slow seismic velocities, reduces the basal drag force acting on the cratonic root, which may also contribute to the longevity of the cratonic lithosphere.
DS202107-1146
2021
Yoshizawa, K.Yoshida, M., Yoshizawa, K.Continental drift with deep cratonic roots.Annual Review of Earth and Planetary Sciences, Vol. 49, pp. 117-139.Mantlecratons

Abstract: The influence of the continental lithosphere and its root (or keel) on the continental drift of Earth is a key element in the history of plate tectonics. Previous geodynamic studies of mantle flow suggested that the cratonic root is moderately mechanically coupled with the underlying mantle, and stable continental drift on Earth's timescales occurs when the effective viscosity contrast between the continental lithosphere and the underlying mantle is approximately 103. Both geodynamics and seismological studies indicate that mechanically weak mobile belts (i.e., orogenic or suture zones) that surround cratons may play a role in the longevity of the cratonic lithosphere over geologically long timescales (i.e., over 1,000 million years) because they act as a buffer region against the high-viscosity cratons. Low-viscosity asthenosphere, characterized by slow seismic velocities, reduces the basal drag force acting on the cratonic root, which may also contribute to the longevity of the cratonic lithosphere. The role of the continental lithosphere and its root on the continental drift is reviewed from recent geodynamic and seismological studies. The cratonic root is moderately mechanically coupled with the underlying mantle and deformed by mantle flow over geological timescales. Orogenic belts or suture zones that surround cratons act as a buffer to protect cratons and are essential for their longevity. Low-viscosity asthenosphere may reduce the basal drag acting on the cratonic root and also contribute to its stability and longevity.
DS202007-1186
2020
Yoshozawa, K.Yoshida, M., Saito, S., Yoshozawa, K.Possible tectonic patterns along the eastern margin of Gondwanaland from numerical studies of mantle convection.Tectonophysics, Vol. 787, 228476, 12p. PdfMantleconvection

Abstract: Two end-member scenarios have been proposed for the tectonic situation along the eastern margins of Gondwanaland before Zealandia was formed ca. 100 million years ago (Ma), namely: (1) A subduction zone located far from the eastern margin of Zealandia, wherein Zealandia may have separated from Gondwanaland by plume push of an active hotspot plume.; (2) A subduction zone located along the eastern margin of Gondwanaland, wherein Zealandia possibly separated from Gondwanaland via trench/subduction retreat. Assuming that the thermal structure of the deep mantle and source of hotspot plumes remained relatively stationary over the last hundred million years, major hotspot plumes with a large buoyancy flux did not exist under Zealandia; the eastern margins of Gondwanaland were far from two large low-shear-velocity provinces under the Africa-Atlantic and South Pacific regions. Herein, through numerical studies of three-dimensional global mantle convection, we examined the mantle convection and surface tectonic patterns at ~100 Ma. The present model considered the real configuration of Gondwanaland at the model surface to observe long-term variations of mantle convection and the resulting surface tectonic conditions. The results demonstrate that the extensive subduction zones developed preferentially along the eastern margin of Gondwanaland when the temperature anomaly of the lower mantle was primarily dominated by high-temperature regions under present-day Africa-Atlantic and South Pacific regions. The results of this study support one of the proposed hypotheses, where the breakup at the eastern margins of Gondwanaland at ~100 Ma occurred via trench/subduction retreat.
DS201708-1584
2015
Yosizawa, K.Yosizawa, K., Kennett, B.L.N.The lithosphere asthenosphere transition and radial anisotropy beneath the Australian continent.Geophysical Research Letters, Vol. 42, 10. pp. 3829-3846.Australiageophysics, seismic

Abstract: A new 3-D S wave speed model for the Australian region derived from multimode surface waves allows us to examine the nature of the lithosphere-asthenosphere transition (LAT) and its relation to radial anisotropy. In eastern Phanerozoic Australia the estimated depths of the LAT tie well with those from receiver functions. However, in the Archean and Proterozoic lithosphere in western and central Australia, the LAT derived from the surface wave model is generally much deeper than the discontinuities recognized from receiver functions and shows a smooth transition. There is significant radial anisotropy (SH?>?SV) in the upper lithosphere as well as in the LAT and the underlying asthenosphere. Strong anisotropy in the asthenosphere reflects the effects of present shear flow in the mantle beneath the continent. The lateral variation of lithospheric anisotropy correlates well with the suture zones between cratonic blocks, representing frozen anisotropy associated with the ancient tectonics of Australia.
DS1995-2108
1995
You, C.F.You, C.F., Spivack, A.J., Gieskes, J.M., RosenbauerExperimental study of boron geochemistry: implications for fluid processes in subduction zonesGeochimica et Cosmochimica Acta, Vol. 59, No. 12, pp. 2435-2442GlobalGeochemistry - experimental, Boron
DS1999-0124
1999
You, C.F.Chan, L.H., Leeman, W.P., You, C.F.Lithium isotopic composition of Central American volcanic arc lavas:implications for modificationChemical Geology, Vol. 160, No. 4, Sept. 2, pp. 255-80.GlobalMantle, Slab derived fluids
DS1996-1581
1996
You, C.-F.You, C.-F., Castillo, P.R., Spivack, A.J.Trace element behaviour in hydrothermal experiments: implications for fluid processes at shallow depths..Earth and Planetary Science Letters, Vol. 140, No. 1-4, May 1, pp. 41-52MantlePetrology -experimental, Subduction zones
DS201502-0127
2015
You, J.You, J.Geoscientists aim to magnify specialized web searching. GeoLink could become search hub for the geoscience community.Sciencemag.org, Vol. 347, 6217 Jan. 2, p. 11 ( 1p)TechnologyGeoLink
DS202110-1624
2021
You, Y.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.
DS2001-1315
2001
You, Z.Zhong, Z., Suo, S., You, Z., Zhang, H., Zhou, H.Major constituents of the Dabie collisional orogenic belt and partial melting in the ultrahigh pressure unitInternational Geology Review, Vol. 43, No. 3, March pp. 226-36.Chinaultra high pressure (UHP), Tectonics
DS2002-1567
2002
You, Z.Su, W., You, Z., Cong, B., Ye, K., Zhong, Z.Cluster of water molecules in garnet from ultrahigh pressure eclogiteGeology, Vol. 30, No. 7, July pp. 611-14.China, easternUHP eclogite, Dabie Shan Mountains
DS200412-2188
2004
You, Z.You, Z., Zhong, Z., Suo, S., Zhou, H.The high temperature garnet pyroxenite enclaves in the spinel bearing peridotie: evidence for partial melting of the upper mantlActa Geologica Sinica, Vol. 78, 1, pp. 89-96.ChinaUHP, magmatism
DS2002-0385
2002
Youbi, N.Doblas, M., Lopez Ruiz, J., Cebria, J.M., Youbi, N., De Groote, E.Mantle insulation beneath the West African Craton during the Precambrian Cambrian transition.Geology, Vol. 30, 9, Sept. pp. 839-42.West AfricaGeothermometry
DS2002-0386
2002
Youbi, N.Doblas, M., Lopez-Ruiz, J., Cebria, J-M., Youbi, N., Degroote, E.Mantle insulation beneath the West African craton during Precambrian - Cambrian transition.Geology, Vol. 30,9,Sept. pp. 839-42.West Africa, BrazilGeothermometry, African Craton
DS201312-0241
2013
Youbi, N.El Bahat, A., Ikenne, M., Soderlund, U., Cousens, B., Youbi, N., Ernst, R., Soulaimani, A., El Janati, M., Hafid, A.U PB baddeleyite ages and geochemistry of dolerite dykes in the Bas Draa In lier of the Anti-Atlas of Morocco: newly identified Ma event in the West African craton.Lithos, Vol. 174, pp. 85-98.Africa, MoroccoGeochronology
DS201312-0511
2013
Youbi, N.Kouyate, D., Soderlund, U., Youbi, N., Ernst, R., Hafid, A., Ikeene, M., Soulaimani, A., Betrand, H., El Janati, M., Rkha, C.U Pb baddeleyite and zircon ages of 2040 Ma, 1650 Ma and 885 Ma on dolerites in the West African Craton ( Anti-Atlas inliers) : possible links to break up of Precambrian supercontinents.Lithos, Vol. 174, pp. 71-84.AfricaGeochronology
DS201312-0999
2013
Youbi, N.Youbi, N., Kouyate, D., Soderlund, U., Ernst, R.E., Soulaimani, A., Hafid, A., Ikenne, M., El Bahat, A., Betrand, H., Chaham, K.R., Ben Abbou, M., Mortaji, A., El Ghorfi, M., Zouhair, M., El Janati, M.The 1750 Ma magmatic event of the West African Craton ( Anti-Atlas) Morocco.Precambrian Research, Vol. 236, pp. 106-123.Africa, MoroccoDike swarms
DS201509-0403
2015
Youbi, N.Jessell, M., Santoul, J., Baratoux, L., Youbi, N., Ernst, R.E., Metelka, V., Miller, J., Perrouty, S.An updated map of West African mafic dykes.Journal of African Earth Sciences, in press availableAfrica, West AfricaGeophysics - magnetics

Abstract: Studies of mafic dyke swarms may simultaneously provide information on the mechanical, geochemical, geochronological and magnetic environments at the time of their formation. The mafic intrusive history of different cratons can also be potentially used to unravel their assembly into their current configuration. The identification and classification of dykes is a first step to all these studies. Fortunately, even in regions with poor outcrop, we can use the strong magnetic response of mafic dykes to identify and map their extent. In West Africa the first maps of mafic dyke distribution were made over 40 years ago, but there are still large areas where there are almost no published data. In this paper we present a significantly updated map of mafic dykes for the West Africa Craton based in large part on new interpretations of the regional airborne magnetic database. This map includes the locations of over three thousand dykes across the craton, which locally shows several orientation clusters that provide a minimum estimate for the total number of dyke swarms in this region. Whilst we will have to wait until systematic dating of the different swarms is completed, we can demonstrate that there is a long and complex history of mafic magmatism across the craton, with up to 26 distinct dyke swarms mapped based according to their orientation. The mapping and dating of these swarms will provide key constraints on the assembly of the fragments that make up the modern continents.
DS201612-2350
2016
Youbi, N.Youbi, N., Ernst, R.E., Soderlund, U., Boumehdi, M.A., Bensalah, M.K., Aarab, E.M.Morocco, North Africa: a dyke swarm bonanza.Acta Geologica Sinica, Vol. 90, July abstract p. 15.Africa, MoroccoDykes
DS201805-0952
2017
Youbi, N.Ikenne, M., Lahna, A.A., Soderlund, U., Tassinar, C.C.G., Ernst, R.E., Pin, Ch., Youbi, N., El Aouli, EH., Hafid, A., Admou, H., Mata, J., Bouougri, EH., Boumehdi, M.A.New Mesoproterozoic age constraints for the Taghdout Group, Anti-Atlas ( Morocco): toward a new lithostratigra[hic framework for the Precambrian in the NW margin of the West African Craton.The First West African Craton and Margins International Workshop WACMA, Held Apr. 24-29. 1p. AbstractAfrica, Moroccogeochronology
DS201902-0261
2019
Youbi, N.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.
DS202004-0500
2020
Youbi, N.Ba, M.H., Ibough, H., Lo, K., Youbi, N., Jaffal, M., Ernst, R.E., Niang, A.J., Dia, I., Abdeina, E.H., Bensalah, M.K., Boumehdi, M.A., Soderlund, U.Spatial and temporal distribution patterns of Precambrian mafic dyke swarms in northern Mauritania ( West African Craton): analysis and results fro remote sensing interpretation, geographical information systems ( GIS), Google Earth TM images, and regionaArabian Journal of Geosciences, Vol. 13, , 209 orchid.org/ 0000-002-3287-9537Africa, Mauritaniacraton

Abstract: We used remote sensing, geographical information systems, Google Earth™ images, and regional geology in order to (i) improve the mapping of linear structures and understand the chronology of different mafic dyke swarms in the Ahmeyim area that belongs to the Archean Tasiast-Tijirit Terrane of the Reguibat Shield, West African craton, NW Mauritania. The spatial and temporal distributions with the trends of the dyke swarms provide important information about geodynamics. The analysis of the mafic dyke swarms map and statistical data allow us to distinguish four mafic dyke swarm sets: a major swarm trending NE-SW to NNE-SSW (80%) and three minor swarms trending EW to ENE-WSW (9.33%), NW-SE to WNW-ESE (9.06%), and NS (1.3%). The major swarms extend over 35 km while the minor swarms do not exceed 13 km. The Google Earth™ images reveal relative ages through crossover relationships. The major NE-SW to NNE-SSW and the minor NS swarms are the oldest generations emplaced in the Ahemyim area. The NW-SE-oriented swarm dykes which are cutting the two former swarms are emplaced later. The minor E-W to WSW-ENE swarms are probably the youngest. A precise U-Pb baddeleyite age of 2733?±?2 Ma has been obtained for the NNE-SSW Ahmeyim Great Dyke. This dyke is approximately 1500 m wide in some zone and extends for more than 150 km. The distinct mafic dyke swarms being identified in this study can potentially be linked with coeval magmatic events on other cratons around the globe to identify reconstructed LIPs and constrain continental reconstructions.
DS202111-1768
2021
Youbi, N.Gong, Z., Evans, D.A.D., Youbi, N., Lahna, A.A., Sodelund, U., Malek, M.A., Wen, B., Jing, X., Ding, J., Boumedhdi, M.A., Ernst, R.E.Reorienting the West African craton in Paleoproterozoic-Msoproterozoic supercontinent Nuna.Geology, Vol. 49, 10, pp. 1171-1176. pdfAfrica, west AfricaNuna

Abstract: The location of the West African craton (WAC) has been poorly constrained in the Paleoproterozoic-Mesoproterozoic supercontinent Nuna (also known as Columbia). Previous Nuna reconstruction models suggested that the WAC was connected to Amazonia in a way similar to their relative position in Gondwana. By an integrated paleomagnetic and geochronological study of the Proterozoic mafic dikes in the Anti-Atlas Belt, Morocco, we provide two reliable paleomagnetic poles to test this connection. Incorporating our new poles with quality-filtered poles from the neighboring cratons of the WAC, we propose an inverted WAC-Amazonia connection, with the northern WAC attached to northeastern Amazonia, as well as a refined configuration of Nuna. Global large igneous province records also conform to our new reconstruction. The inverted WAC-Amazonia connection suggests a substantial change in their relative orientation from Nuna to Gondwana, providing an additional example of large-magnitude cumulative azimuthal rotations between adjacent continental blocks over supercontinental cycles.
DS201212-0534
2012
Youmen, D.Owona, S., Tichomirowa, M., Ratschbacher, L., Ondoa, J.M., Youmen, D., Pfander, J., Tchoua, F.M., Affaton, P., Ekodeck, G.E.New igneous zircon Pb/Pb and metamorphic Rb/Sr ages in the Yaounde Group, Cameroon, Central Africa): implications for the Central African fold belt evolution close to the Congo Craton.International Journal of Earth Sciences, Vol. 101, 7, pp. 1689-1703.Africa, CameroonGeochronology
DS201212-0535
2012
Youmen, D.Owona, S., Tichomirowa, M., Ratschbacher, L., Ondoa, W.J., Youmen, D., Pfander, J., Tchoua, F.M., Affaton, P., Ekodeck, G.E.New igneous zircon Pb/Pb and metamorphic Rb/Sr ages in the Yaounde Group ( Cameron, Central Africa): implications for the Central African fold belt evolution close to the Congo Craton.International Journal of Earth Sciences, Vol. 101, pp. 1689-1703.Africa, CameroonGeochronology
DS1994-1248
1994
Younessi, R.Mucke, A., Younessi, R.Magnetite-apatite deposits Kiruna type along Sanandaj Sirjan zone and Bafqarea, calc alkaline and carbonatites.Mineralogy and Petrology, Vol. 50, pp. 219-244.IranCarbonatite
DS202103-0394
2021
Young, A.Merdith, A.S., Williams, S.E., Collins, A.S., Tetley, M.G., Mulder, J.A., Blades, M.L., Young, A., Armistead, S.E., Cannon, J., Zahirovic, S., Muller, R.D.Extending full plate tectonic models into deep time: linking the Neoproterozoic and the Phanerozoic.Earth Science Reviews, Vol. 214, 44p. PdfMantleplate tectonics

Abstract: Recent progress in plate tectonic reconstructions has seen models move beyond the classical idea of continental drift by attempting to reconstruct the full evolving configuration of tectonic plates and plate boundaries. A particular problem for the Neoproterozoic and Cambrian is that many existing interpretations of geological and palaeomagnetic data have remained disconnected from younger, better-constrained periods in Earth history. An important test of deep time reconstructions is therefore to demonstrate the continuous kinematic viability of tectonic motions across multiple supercontinent cycles. We present, for the first time, a continuous full-plate model spanning 1 Ga to the present-day, that includes a revised and improved model for the Neoproterozoic-Cambrian (1000-520 Ma) that connects with models of the Phanerozoic, thereby opening up pre-Gondwana times for quantitative analysis and further regional refinements. In this contribution, we first summarise methodological approaches to full-plate modelling and review the existing full-plate models in order to select appropriate models that produce a single continuous model. Our model is presented in a palaeomagnetic reference frame, with a newly-derived apparent polar wander path for Gondwana from 540 to 320 Ma, and a global apparent polar wander path from 320 to 0 Ma. We stress, though while we have used palaeomagnetic data when available, the model is also geologically constrained, based on preserved data from past-plate boundaries. This study is intended as a first step in the direction of a detailed and self-consistent tectonic reconstruction for the last billion years of Earth history, and our model files are released to facilitate community development.
DS202109-1481
2021
Young, A.Meredith, A.S., Williams, S.E., Collins, A.S., Tetley, M.G., Mulder, J.A., Blades, M.L., Young, A., Armistead, S.E., Cannon, J., Zahirovic, S., Muller, R.D.Extending full plate tectonic models into deep time: linking the Neoproterozoic and the Phanerozoic.Earth Science Reviews , Vol. 214, 103477, 44p. PdfMantleplate tectonics, Rodinia, Gondwana

Abstract: Recent progress in plate tectonic reconstructions has seen models move beyond the classical idea of continental drift by attempting to reconstruct the full evolving configuration of tectonic plates and plate boundaries. A particular problem for the Neoproterozoic and Cambrian is that many existing interpretations of geological and palaeomagnetic data have remained disconnected from younger, better-constrained periods in Earth history. An important test of deep time reconstructions is therefore to demonstrate the continuous kinematic viability of tectonic motions across multiple supercontinent cycles. We present, for the first time, a continuous full-plate model spanning 1 Ga to the present-day, that includes a revised and improved model for the Neoproterozoic-Cambrian (1000-520 Ma) that connects with models of the Phanerozoic, thereby opening up pre-Gondwana times for quantitative analysis and further regional refinements. In this contribution, we first summarise methodological approaches to full-plate modelling and review the existing full-plate models in order to select appropriate models that produce a single continuous model. Our model is presented in a palaeomagnetic reference frame, with a newly-derived apparent polar wander path for Gondwana from 540 to 320 Ma, and a global apparent polar wander path from 320 to 0 Ma. We stress, though while we have used palaeomagnetic data when available, the model is also geologically constrained, based on preserved data from past-plate boundaries. This study is intended as a first step in the direction of a detailed and self-consistent tectonic reconstruction for the last billion years of Earth history, and our model files are released to facilitate community development.
DS1992-1615
1992
Young, A.V.Wadge, G., Young, A.V., Mason, D.C.Simulation of geological processes using an expert systemJournal of Geology Society of London, Vol. 149, No. 3, May pp. 455-464GlobalComputers, Expert system
DS1996-0815
1996
Young, C.J.Lay, T., Young, C.J.Imaging scattering structures in the lower mantle by migration of long period S waves.Journal of Geophysical Research, Vol. 101, No. B9, Sept. 10, pp. 20, 023-40.MantleStructure, Geophysics -seismic
DS1987-0812
1987
Young, C.T.Wunderman, R.L., Young, C.T.Is the path of the Keweenawan midcontinent rift controlled by an older continental sutureGeological Society of America, Vol. 19, No. 7 annual meeting abstracts, p.900. abstracMidcontinentTectonics
DS2003-1534
2003
Young, D.A.Young, D.A.Mind over magma: the history of igneous petrologyPrinceton University Press, GlobalVolcanism, theories, petrography, geochemistry, dynamic
DS200412-2189
2003
Young, D.A.Young, D.A.Mind over magma: the history of igneous petrology.Princeton University Press, 681p.GlobalBook
DS1997-1284
1997
Young, D.N.Young, D.N., Zhao, J.X., McCulloch, M.T.Geochemical and Strontium-neodymium isotopic mapping of source provinces for the Mawson charnockites..Precambrian Research, Vol. 86, No. 1/2, Dec. 15, pp. 1-20AntarcticaTectonics - Proterozoic, Gondwana
DS200912-0841
2009
Young, E.D.Young, E.D., Tonui, E., Manning, C.E., Schauble, E., Macris, C.A.Spinel olivine magnesium isotope thermometry in the mantle and implications for the MG isotopic composition of Earth.Earth and Planetary Science Letters, Vol. 288, 3-4, pp. 524-533.MantleGeothermometry
DS201012-0881
2009
Young, E.D.Young, E.D., Tonui, E., Manning, C.E., Schauble, E., Macris, C.A.Spinel olivine magnesium isotope thermometry in the mantle and implications for the Mg isotopic composition of Earth.Earth and Planetary Science Letters, Vol. 288, pp. 524-533..MantleGeochemistry
DS201603-0433
2016
Young, E.D.Young, E.D., Kohl, I.E., Warren, P.H., Rubie, D.C., Jacobson, S.A., Morbidelli, A.Oxygen isotopic evidence for vigorous mixing during the moon forming giant impact.Science, Vol. 6272, pp. 493-496.MantleMeteorite

Abstract: Earth and the Moon are shown here to have indistinguishable oxygen isotope ratios, with a difference in ??17O of ?1 ± 5 parts per million (2 standard error). On the basis of these data and our new planet formation simulations that include a realistic model for primordial oxygen isotopic reservoirs, our results favor vigorous mixing during the giant impact and therefore a high-energy, high-angular-momentum impact. The results indicate that the late veneer impactors had an average ??17O within approximately 1 per mil of the terrestrial value, limiting possible sources for this late addition of mass to the Earth-Moon system.
DS202005-0744
2020
Young, E.D.Labidi, J., Barry, P.H., Bekaert, D.V., Broadley, M.W., Marty, B., Giunta, T., Warr, O., Sherwood Lollar, B., Fischer, T.P., Avice, G., Caracusi, A., Ballentine, C.J., Halldorsson, S.A., Stefansson, A., Kurz, M.D., Kohl, I.E., Young, E.D.Hydrothermal 15N15N abundances constrain the origins of mantle nitrogen.Nature, Vol. 580, 7803 pp. 367-371. Mantlenitrogen

Abstract: Nitrogen is the main constituent of the Earth’s atmosphere, but its provenance in the Earth’s mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earth’s accretion versus that subducted from the Earth’s surface is unclear1,2,3,4,5,6. Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare 15N15N isotopologue of N2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle ?15N (the fractional difference in 15N/14N from air), N2/36Ar and N2/3He. Our results show that negative ?15N values observed in gases, previously regarded as indicating a mantle origin for nitrogen7,8,9,10, in fact represent dominantly air-derived N2 that experienced 15N/14N fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the 15N15N data allow extrapolations that characterize mantle endmember ?15N, N2/36Ar and N2/3He values. We show that the Eifel region has slightly increased ?15N and N2/36Ar values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts11, consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has ?15N values substantially greater than that of the convective mantle, resembling surface components12,13,14,15, its N2/36Ar and N2/3He ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume ?15N values may both be dominantly primordial features.
DS1992-1248
1992
Young, G.Rainbird, R.H., Heaman, L.M., Young, G.Sampling Laurentia: detrital zircon geochronology offers evidence for an extensive Neoproterozoic river system originating from the Grenville orogenGeology, Vol. 20, No. 4, April pp. 351-354Victoria IslandShaler Group, Geochronology
DS201903-0553
2019
Young, G.Young, G.Aspects of the Archean- Proterozoic transition: how the great Huronian glacial event was inititated by rift-related uplift and terminated at the rift-drift transition during breakup of Lauroscandia.Earth-Science Reviews, Vol. 190, pp. 171-189.Canada, Africa, South Africasedimentology

Abstract: The Archean-Proterozoic transition was among the most important in geological history for it includes evidence of establishment of ‘modern-style’ plate tectonics, unprecedented paleoclimatic upheavals, and oxygenation of the atmosphere. The early Paleoproterozoic sedimentary record includes evidence of the world's first widespread glacial episodes, which have come to be known as the ‘Huronian Glacial Event’. None of these important changes coincides precisely with the accepted date of 2.5?Ga for the ‘boundary’ between the two great Precambrian eons. Rather, the geological record contains evidence of gradual transitions over many millions of years. For example the Archean sedimentary record in areas such as South Africa includes evidence of stable conditions (e.g. the Pongola Supergroup) that were not achieved in the Laurentian craton until much later during the Paleoproterozoic Era. The Pongola Supergroup in South Africa contains some of the world's oldest (c. 2.9?Ga) but locally developed glacial deposits. Many of these important changes are now considered to have been gradual and oscillatory in nature, including evidence of ‘whiffs of oxygen’ in Archean rocks, long before the Paleoproterozoic Great Oxidation Event. Oxidation of the oceans was also a long and extremely complex process, the details of which are still poorly understood. Glaciations near the beginning of the Paleoproterozoic Era have been considered by some to have been world-spanning ‘snowball Earth’ events. Repeated Huronian glaciations were probably brought about by weathering of Lauroscandia, the world's first ‘supercraton’, controlled by episodic rift-related uplifts during its disintegration. Among these glaciations only the third, represented by the Gowganda Formation and equivalents, was widespread throughout Lauroscandia. Because the two older glaciogenic units are known from only two locations in North America, their formation and preservation were probably controlled by local tectonic events. In like fashion, Paleoproterozoic glaciogenic units in South Africa and Western Australia appear to be local deposits from mountain glaciers formed during periods of tectonically generated (compressional?) uplift. The restricted distribution and diachronous nature of such tectonic events, and associated glaciogenic deposits, cast doubt on the viability of attempts at global correlations of individual Paleoproterozoic glaciogenic formations and on the existence of a Paleoproterozoic (or Neoproterozoic?) snowball Earth.
DS1860-1011
1897
Young, G.J.Young, G.J.The Working of Unstratified Mineral Deposits (1897)New York: Mcgraw Hill, 466P.Africa, South AfricaMining recovery
DS1920-0355
1927
Young, G.J.Young, G.J.The Working of Unstratified Mineral Deposits (1927)London: E. Benn., 466P.South AfricaMining Engineering
DS1930-0128
1932
Young, G.J.Young, G.J.Elements of MiningNew York, London: Mcgraw Hill, 707P.South AfricaMining Engineering
DS1982-0652
1982
Young, G.M.Young, G.M.Excursion 13b: Depositional Environments and Tectonic Setting of the Early Proterozoic Huronian Supergroup.International Association SEDIMENTOLOGIST FIELD EXCURSION GUIDEBOOK 13B, 79P.GlobalStratigraphy, Guidebook, Elliot, Hough Lake, Quirke Lake, Cobalt
DS1991-1914
1991
Young, G.M.Young, G.M.The geologic record of glaciation: relevance to the climatic history ofearthGeoscience Canada, Vol. 18, No. 3, pp. 100-108GlobalGlobal warming, Glaciation -climates, geomorphology
DS1992-1724
1992
Young, G.M.Young, G.M.Late Proterozoic stratigraphy and the Canada-Australia connectionGeology, Vol. 20, No. 3, March pp. 215-218Canada, Australia, GreenlandProterozoic, Stratigraphy
DS1993-1803
1993
Young, G.M.Young, G.M.Impacts, tillites and the breakup of Gondwanaland: a discussionJournal of Geology, Vol. 101, pp. 675-9.Geomorphology
DS1995-0525
1995
Young, G.M.Fedo, C.M., Nesbitt, H.W., Young, G.M.Unravelling the effects of potassium metasomatism in sedimentary rocks andpaleosols, with implications ..Geology, Vol. 23, No. 10, October pp. 921-924GlobalPaleosols, Paleoweathering
DS1995-2109
1995
Young, G.M.Young, G.M.Are Neoproterozoic glacial deposits preserved on the margins of Laurentia related to the fragmentation of two supercontinents?Geology, Vol. 23, No. 2, Feb. pp. 153-156GlobalPaleomagnetism, Proterozoic
DS1995-2110
1995
Young, G.M.Young, G.M.The Huronian Supergroup in the context of the Paleoproterozoic Wilson Cycle in the Great Lakes regionCan. Min. Northern Margin S. Canadian shield, Vol. 33, p.921.OntarioGrenville Province, Not specific to kimberlites
DS1999-0821
1999
Young, G.M.Young, G.M., Von Brunn, V., Gold, D.G.J., Minter, W.E.L.Earth's oldest reported glaciation: physical and chemical evidence from the Archean Mozaan Group ( 2.9GaJournal of Geology, Vol. 106, No. 5, Sept. pp. 523-38.South AfricaGeomorphology, Kaapvaal Craton, Pongola Group
DS200512-1222
2004
Young, G.M.Young, G.M.Earth's earliest extensive glaciations: tectonic setting and stratigraphic context of Paleoproterozoic glaciogenic deposits.American Geophysical Union, Geophysical Monograph, No. 146, pp. 161-182.Geomorphology - tectonics
DS201312-1000
2013
Young, G.M.Young, G.M.Precambrian supercontinents, glaciations, atmospheric oxygenation, metazoan evolution and an impact that have changed the second half of Earth history.Geoscience Frontiers, Vol. 4, 3, pp. 247-261.MantleHistory
DS1981-0428
1981
Young, J.Wilcox, J.D., Young, J.Arkansaw Incredible Diamond Mine StorySpecialty Printing Company, News Supplement., United States, Gulf Coast, Arkansas, PennsylvaniaHistory
DS200712-0213
2007
Young, J.P.Dai, S., Young, J.P., Begun, G.M., Mamantov, G.Temperature measurement by observation of the Raman spectrum of diamond.Applied Spectroscopy, Vol. 46, 2, pp. 375-377.TechnologySpectroscopy
DS201412-0813
2014
Young, K.R.Shinn, J.E., King, B., Young, K.R., Crews, K.A.Variable adaptations: micro-politics of environmental displacement in the Okavango Delta, Botswana.Geoforum, Vol. 57, pp. 21-29.Africa, BotswanaCSR
DS1900-0283
1904
Young, M.Young, M.Diamond from Gold Creek Brown County, IndianaLetter To Tiffany's., AUG. 29TH.United States, IndianaDiamond Occurrences
DS200512-1112
2005
Young, M.Utting, D., Little, E., Brown, O., Young, M., Taylor, J.Glacial geology, drift bedrock prospecting and related remote sensing application on northern Baffin Island, Nunavut.Geological Survey of Canada Open File, OF 4736 $ 15.00 1 colour posterCanada, NunavutRemote sensing
DS201312-0563
2013
Young, M.Machado, G., Bilodeau, C., Takpanie, R., St.Onge, M., Rayner, N., Skipton, D., From, R., MacKay, C., Young, M., Creason, G., Braden, Z.Regional bedrock mapping, Hall Peninsula, Nunavut.Geoscience Forum 40 NWT, abstract only p. 26Canada, NunavutMapping
DS201312-0916
2013
Young, M.K.Tkalcic, H., Young, M.K., Bodin, T., Ngo, S., Sambridge, M.The shuffling rotation of the Earth's inner core.Nature Geoscience, Vol. 6, pp. 497-502.MantleGeodynamics
DS201412-1011
2013
Young, M.K.Young, M.K., Tkalcic, H., Bodin, T., Sambridge, M.Global P wave tomography of Earth's lowermost mantle from partition modeling.Journal of Geophysical Research, Vol. 118, 10, pp. 5467-5486.MantleGeophysics - tomography
DS202011-2063
2020
Young, N.Thurston, M., Young, N., Gordon-Coker, C.Farewell to Wynand Kleingeld.Mathematical Geosciences, Vol. 52, pp. 971-973.GlobalKleingeld
DS200512-1223
2004
Young, R.Young, R.Dilemmas and advances in corporate social responsibility in Brazil.Natural Resources Forum, Vol. 28, 4, pp. 291-301.South America, BrazilEconomics - social responsibility
DS200612-0258
2005
Young, R.Clarke, G., Young, R.Unique upper stratigraphy of the A154N kimberlite.32ndYellowknife Geoscience Forum, POSTERCanada, Northwest TerritoriesGeology
DS200712-0754
2007
Young, R.Moss, S., Russel, J.K., Fomrades, G., Young, R., McLean, H.Crater in-fill at Diavik: facies architecture, textures, volcanic processes and implications.Geological Association of Canada, Gac-Mac Yellowknife 2007, 1 pg. abstract p.57-58.Canada, Northwest TerritoriesDiavik petrology
DS1991-0119
1991
Young, R.A.Billingsley, G.H., Weinrich, K.J., Huntoon, P.W., Young, R.A.Breccia pipes and geologic map of the southwestern Hualapai Indian reservation and vicinity, ArizonaUnited States Geological Survey (USGS) Open File, No. 86-0458-D, 33p. 2 mapsArizonaBreccia pipes, Map
DS2000-1044
2000
Young, R.A.Young, R.A., Burns, J.A., Sjogren, D.B., Kvill, D.Post glacial terraces of West Central Alberta and inferences models of subglacial and deglacial processesGeological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-511.AlbertaGeomorphology
DS1900-0415
1906
Young, R.B.Johnson, J.P., Young, R.B.The Relation of the Ancient Deposits of the Vaal River to The Palaeolithic Period of South Africa.Geological Society of South Africa Transactions, Vol. 9, PP. 53-56.Africa, South AfricaArchaeology, Geomorphology
DS1900-0463
1906
Young, R.B.Young, R.B.The Calcareous Rocks of Griqualand WestGeological Society of South Africa Transactions, Vol. 9, PP. 57-66.Africa, South AfricaGeology, Petrography
DS1900-0464
1906
Young, R.B.Young, R.B., Johnson, J.P.Glacial Phenomena in Griqualand WestGeological Society of South Africa Transactions, Vol. 9, PP. 34-39.Africa, South AfricaGeomorphology
DS1910-0392
1913
Young, R.B.Young, R.B.Note on the Diamonds in the BanketGeological Society of South Africa Transactions, Vol. 16, PP. 39-40.South AfricaMineralogy, Diamonds In Precambrian Conglomerate
DS1910-0547
1917
Young, R.B.Young, R.B.The Banket. a Study of the Auriferous Conglomerates of the Witwatersrand and the Associated Rocks.London: Gurney And Jackson., 125P.South AfricaDiamond, Kimberley
DS1950-0049
1950
Young, R.S.Young, R.S.The Diamond Research LaboratoryGems And Gemology, Vol. 6, No. 11, FALL, PP. 327-333.South AfricaHistory
DS1950-0155
1953
Young, R.S.Stent, C., Young, R.S.Mineral Dressing in Diamond MiningInstitute of Mining and Metallurgy., PP. 647-655.South AfricaPremier, Heavy Media, Diamond Recovery
DS1950-0197
1954
Young, R.S.Young, R.S.Cobalt in KimberliteAmerican MINERALOGIST., Vol. 39, No. 1-2, PP. 143-144.South AfricaMineralogy
DS1950-0247
1955
Young, R.S.Young, R.S., Bailey, R.A.A Mica Peridotite Dike Near Front Royal VirginiaVirginia Journal of Science, Vol. 6 PP. 282-283.Appalachia, VirginiaRelated Rocks, Petrography
DS1989-1673
1989
Young, R.W.Young, R.W.Crustal constraints on the evolution of the continental divide of easternAustraliaGeology, Vol. 17, No. 6, June pp. 528-530AustraliaGeophysics -Gravity, Tectonics
DS1992-1725
1992
Young, R.W.Young, R.W.Structural heritage and planation in the evolution of landforms in the EastKimberleyAustralian Journal of Earth Science, Vol. 39, pp. 141-151AustraliaStructure, Craton
DS2003-0341
2003
Young-ChungDobrzhinetskaya, 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
DS200412-0464
2003
Young-ChungDobrzhinetskaya, 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
DS1997-0074
1997
Younger, P.L.Banks, D., Younger, P.L., Banks, S.B.Mine water chemistry: the good, the bad and the uglyEnvironmental Geology, Vol. 32, No. 3, Oct. 1, pp. 157-GlobalEnvironmental, Mining - waste
DS1860-1050
1898
Younghusband, F.E.Younghusband, F.E.South Africa of TodayLondon:, Africa, South AfricaHistory
DS200912-0842
2009
Youngs, B.A.R.Youngs, B.A.R., Bercovici, D.Stability of a compressible hydrous melt layer above the transition zone.Earth and Planetary Science Letters, Vol. 278, 1-2, Feb. 15, pp. 78-86.MantleMelting
DS200912-0843
2009
Youngs, B.A.R.Youngs, B.A.R., Houseman, G.A.Formation of steep sided tomography from compositionally distinct dense material at the base of the mantle.Journal of Geophysical Research, Vol. 114, B4, B004404.MantleTomography
DS201811-2621
2018
Younus, F.Yang, H., Xiao, J., Yao, Z., Zhang, X., Younus, F., Melnik, R., Wen, B.Homogeneous and heterogenous dislocation nucleation in diamond.Diamond & Related Materials, Vol. 88, pp. 110-117.Mantlediamond morphology

Abstract: Dislocation nucleation plays a key role in plastic deformation of diamond crystal. In this paper, homogeneous and heterogeneous nucleation nature for diamond glide set dislocation and shuffle set dislocation is studied by combining molecular dynamics method and continuum mechanics models. Our results show that although heterogeneous dislocation nucleation can decrease its activation energy, the activation energy at 0?GPa for diamond heterogeneous nucleation is still in the range of 100?eV. For glide set and shuffle set homogeneous nucleation, their critical nucleation shear stress approaches to diamond's ideal shear strength which implies that those dislocations do not nucleate before diamond structural instability only by a purely shearing manner. While for glide set and shuffle set heterogeneous nucleation, their critical nucleation shear stresses are 28.9?GPa and 48.2?GPa, these values are less than diamond's ideal shear strength which implies that these dislocations may be nucleated heterogeneously under certain shear stress condition. In addition, our results also indicate there exists a deformation mode transformation for diamond deformation behavior at strain rate of 10?3/s. Our results provide a new insight into diamond dislocation nucleation and deformation.
DS202007-1139
2020
Youri, K.Eppelbaum, L.V., Youri, K.Significant tectono-geophysical features of the African-Arabian tectonic region: an overview.Geotectonics, Vol. 54, 2, pp. 266-283.AfricaArabian craton

Abstract: Satellite gravimetry is recognized now as powerful and reliable tool for regional tectono-geodynamic zonation. The studied region contains intricate geodynamical features (high seismological indicators, active rift systems and collision processes), richest structural arrangement (existence of mosaic blocks of oceanic and continental Earth’s crust of various age), and a number of high-amplitude gravity anomalies and complex geomagnetic pattern. The most hydrocarbon reserves and diamonds, gold, platinum and deposits occur in this region. Comprehensive analysis of satellite derived gravity data by different methodologies were used to develop a sequence of maps specifying crucial properties of the region deep structure. Combined analysis of the compiled gravity map and its transformations with obtained geological data allowed to detecting significant geotectonic features of lithosphere of the region. For instance, Zagros-Makran terrane was classified as a separately developing structural segment (element) of the Arabian craton. Detailed examination of numerous geological sources and their combined examination with the GPS pattern, paleomagnetic, tectonic, geoid isoline map, seismic and other data revealed some sophisticated tectono-geophysical feature apparently located in middle-lower mantle below the Arabian-African region.
DS202012-2213
2021
Youri, K.Eppelbaum, L.V., Ben-Avraham, Z., Youri, K., Kaban, M.K.Giant quasi-ring structure if the African-Arabian junction: results derived from the geological-geophsyical data integration.Geotectonics, Mantletectonics

Abstract: The tectonic-geodynamic characteristics of the North African-Arabian region are complicated by interaction of numerous factors. To study this interaction, we primarily used the satellite gravity data (retracked to the Earth's surface), recognized as a powerful tool for tectonic-geodynamic zonation. The applied polynomial averaging of gravity data indicated the presence of a giant, deep quasi-ring structure in the Eastern Mediterranean, the center of which is located under the Island of Cyprus. Simultaneously, the geometrical center of the revealed structure coincides with the Earth's critical latitude of 35?. A quantitative analysis of the obtained gravitational anomaly made it possible to estimate the depth of the upper edge of the anomalous body as 1650?1700 km. The GPS vector map coinciding with the gravitational trend indicates counterclockwise rotation of this structure. Review of paleomagnetic data on the projection of the discovered structure into the earth's surface also confirms its counterclockwise rotation. The analysis of the geoid anomalies map and seismic tomography data commonly approve presence of this deep anomaly. The structural and geodynamic characteristics of the region and paleobiogeographic data are consistent with the proposed physical-geological model. Comprehensive analysis of petrological, mineralogical, and tectonic data suggests a relationship between the discovered deep structure and near-surface processes. The revealed geological deep structure sheds light on specific anomalous effects in the upper crustal layer, including the high-intensity Cyprus gravity anomaly, counterclockwise rotation of the Mesozoic terrane belt, configuration of the Sinai plate, and the asymmetry of sedimentary basins along the continental faults.
DS202104-0574
2021
Youri, K.Eppelbaum, L.V., Ben-Avraham, Z., Youri, K., Cloetough, S., Kaban, M.K.Giant quasi-ring mantle structure in the African-Arabian junction: results derived from the geological-geophysical data integration.Geotectonics, 10.1134/S0016 85212010052Africageophysics - seismic

Abstract: The tectonic-geodynamic characteristics of the North African-Arabian region are complicated by interaction of numerous factors. To study this interaction, we primarily used the satellite gravity data (retracked to the Earth's surface), recognized as a powerful tool for tectonic-geodynamic zonation. The applied polynomial averaging of gravity data indicated the presence of a giant, deep quasi-ring structure in the Eastern Mediterranean, the center of which is located under the Island of Cyprus. Simultaneously, the geometrical center of the revealed structure coincides with the Earth's critical latitude of 35?. A quantitative analysis of the obtained gravitational anomaly made it possible to estimate the depth of the upper edge of the anomalous body as 1650?1700 km. The GPS vector map coinciding with the gravitational trend indicates counterclockwise rotation of this structure. Review of paleomagnetic data on the projection of the discovered structure into the earth's surface also confirms its counterclockwise rotation. The analysis of the geoid anomalies map and seismic tomography data commonly approve presence of this deep anomaly. The structural and geodynamic characteristics of the region and paleobiogeographic data are consistent with the proposed physical-geological model. Comprehensive analysis of petrological, mineralogical, and tectonic data suggests a relationship between the discovered deep structure and near-surface processes. The revealed geological deep structure sheds light on specific anomalous effects in the upper crustal layer, including the high-intensity Cyprus gravity anomaly, counterclockwise rotation of the Mesozoic terrane belt, configuration of the Sinai plate, and the asymmetry of sedimentary basins along the continental faults.
DS201902-0314
2019
Yousefi, M.Roshanravan, B., Aghajani, H., Yousefi, M., Kreuzer, O.An improved prediction-area plot for prospectivity analysis of mineral deposits ( not specific to diamonds).Natural Resources Research, doi.org/10.1007/s11053-018-9439-7 17p.Iranchromite

Abstract: In this paper an improved prediction-area plot has been developed. This type of plot includes performance measures similar to other existing methods (receiver operating characteristics, success-rate curves and ordinary prediction-area plots) and, therefore, offers a reliable method for evaluating the performance of spatial evidence maps and prospectivity models. To demonstrate the reliability of the improved prediction-area plot proposed, we investigated the benefits of augmented targeting criteria through remotely sensed exploration features, compared to only geological map-derived criteria, for mineral prospectivity analysis using as an example the podiform chromite deposits of the Sabzevar Ophiolite Belt, Iran. The application of the newly developed improved prediction-area plot to the prospectivity models generated in this study indicated that the augmented targeting criteria by using remote sensing data perform better than non-updated geological map-derived criteria, and that model effectiveness can be improved by using an integrated approach that entails geologic remote sensing.
DS1993-1804
1993
Youxue ZhangYouxue Zhang, Zindler, A.Distribution and evolution of carbon and nitrogen in earthEarth and Planetary Science Letters, Vol. 117, pp. 331-345.MantleGeochemical cycle, Carbon
DS1998-1618
1998
Youzhu, L.Youzhu, L.Deep xenoliths and Cenozoic pyroxene geotherm of east ChinaRussian Geology and Geophysics, Vol. 39, No. 3, pp. 353-60.China, eastern ChinaXenoliths, Geothermometry
DS201412-0092
2014
Y-QCampbell, I., Stepanov, A., Liang, H-Y., Allen, C., Norman, M., Zhang, Y-Q, Xie, Y-W.The origin of shoshonites: new insights from the Tertiary high-potassium intrusions of eastern Tibet.Contributions to Mineralogy and Petrology, Vol. 167, 3, pp. 1-22.Asia, TibetShoshonite
DS200512-0760
2004
Yreva, O.P.Nadolinnyi, V.A., Yreva, O.P., Yelisseyev, A.P., Pokhilenko, N.P., Chepurov, A.A.Disruption of B1 nitrogen defects in 1aB natural diamonds.Doklady Earth Sciences, Vol. 399A, Nov-Dec. pp. 1228-1272.Diamond morphology
DS1997-1127
1997
YruinSuvorov, V.D., Timirshin, Yruin, Parasotka, MatveevRatio of deep seated and near surface structures in the southern part Of the Yakutian kimberlite province.Russian Geology and Geophysics, Vol. 38, No. 5, pp. 1054-61.Russia, YakutiaGeophysics - seismics, Tectonics, structures
DS200712-1184
2007
Y-SWu, Y-B., Gao, S., Zhang, H-F., Wang, S-H., Jiao, W-F., Liu, Y-S, Yuan, H-L.Timing of UHP metamorphism in the Hongan area, western Dabie Mountains China: evidence from zircon Pb age, trace element and Hf isotope composition.Contributions to Mineralogy and Petrology, Vol. 155, 1, pp. 123-133.ChinaUHP
DS200812-1104
2008
YuSpetsius, Z.V., Zezekalo, M., Yu, Tarskhix, O.Y.Pecularities of mineralogy and petrography of the upper Muna field kimberlites: application to the lithospheric mantle composition.Deep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., 2008 pp. 137-146.Russia, SiberiaDeposit - Muna field
DS200912-0860
2009
YuZheng, 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
YuZheng, 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
DS201312-0293
2013
YuGao, S.S., Liu, Reed, Yu, Massinque, Mdala, Moidaki, Mutamina, Atekwana, Ingate, ReuschSeismic arrays to study African Rift initiation.EOS Transaction of AGU, Vol. 94, 24, June 11, pp. 213-214.Africa, southern AfricaGeophysics - seismics
DS201806-1250
2018
YuShule, Yu, Garnero, E.J.Ultralow velocity zone locations: a global assessment.Geochemistry, Geophysics, Geosystems, Vol. 19, 2, pp. 396-414.Mantlecore, boundary

Abstract: We have compiled all previous ultralow velocity zone (ULVZ) studies, and digitized their core?mantle boundary (CMB) sampling locations. For studies that presented sampling locations based on infinite frequency ray theory, we approximated Fresnel zones onto a 0.5° × 0.5° grid. Results for these studies were separated according to wave type: (1) core?reflected phases, which have a single location of ULVZ sampling (ScS, ScP, PcP), (2) core waves that can sample ULVZs at the core entrance and exit locations of the wave (e.g., SPdKS, PKKP, and PKP), and (3) waves which have uncertainties of ULVZ location due to long CMB sampling paths, e.g., diffracted energy sampling over a broad region (Pdiff, Sdiff). For studies that presented specific modeled ULVZ geographical shapes or PKP scatter probability maps, we digitized the regions. We present summary maps of the ULVZ coverage, as well as published locations arguing against ULVZ presence. A key finding is that there is not a simple mapping between lowermost mantle reduced tomographic velocities and observed ULVZ locations, especially given the presence of ULVZs outside of lowermost mantle large low velocity provinces (LLVPs). Significant location uncertainty exists for some of the ULVZ imaging wave types. Nonetheless, this compilation supports a compositionally distinct origin for at least some ULVZs. ULVZs are more likely to be found near LLVP boundaries, however, their relationship to overlying surface locations of hot spots are less obvious. The new digital ULVZ database is freely available for download.
DS201912-2795
2019
Yu, A.Krivovichev, S.V., Yakovenchuk, V.N., Panikorovskii, T.L., Savchenko, E.E., Pakhailova, Yu, A., Selivanova, E.A., Kadyrova, G.I., Ivanyuk, G.Yu.,Krivovchev, S.V.Nikmelnikovite: Ca 12 Fe 2+ Fe 3+3 Al3(SiO4) 6(OH)20: a new mineral from the Kovdor Massif ( Kola Peninsula, Russia)Doklady Earth Sciences, Vol. 488, 2, pp. 1200-1202.Russia, Kola Peninsuladeposit - Kovdor
DS202006-0959
2020
Yu, B.D.Yang, J.W., Park, J.H., Byun, M.G., Park, J., Yu, B.D., Hwan, N.M.Beyond carbon solvency effects of catalytic metal Ni on diamond growth.Diamonds & Related Materials, in press available, 27p. PdfGlobalnitrogen

Abstract: To understand the physical and chemical roles of catalytic metal Ni in the growth of diamond, ab-initio calculations of the structural, electronic, and kinetic properties of a Ni-covered C (111) surface were performed. Findings from this theoretical study highlight two important roles of Ni in addition to its carbon-solvency effect, widely known to play a catalytic role in the growth of diamond. The first role is to facilitate the formation of a thermodynamically stable Ni-C interface with a diamond bulk-like structure and the second is to induce surfactant-mediated growth enabling continuous layer-by-layer growth for diamond.
DS200412-2223
2004
Yu, C.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
DS200512-1261
2004
Yu, C.Zheng, J., Yu, C., Lu, F.Zircon geochronology and geochemistry of mafic xenoliths from Liaoning kimberlites: back the early evolution of the lower crust, north Chin a Craton.Science China Earth Sciences, Vol.47, 11, pp. 961-972. Ingenta 1045518755ChinaGeochronology - Liaoning
DS201412-1000
2014
Yu, C.Yang, J-J., Fan, Z.F., Yu, C., Yan, R.Coseismic formation of eclogite facies cataclastic dykes at Yangkou in the Chinese Sulu UHP metamorphic belt.Journal of Metamorphic Geology, Vol. 32, 9, pp. 937-960.ChinaUHP
DS201907-1556
2019
Yu, C.Kurinsky, N., Yu, C., Hochberg, Y., Cabrera, B.Diamond detectors for direct detection of sub-GeV dark matter.Physical Review, Vol. 99, June 15, 123005Spacediamond morphology

Abstract: We propose to use high-purity lab-grown diamond for the detection of sub-GeV dark matter. Diamond targets can be sensitive to both nuclear and electron recoils from dark matter scattering in the MeV and above mass range, as well as to absorption processes of dark matter with masses between sub-eV to 10's of eV. Compared to other proposed semiconducting targets such as germanium and silicon, diamond detectors can probe lower dark matter masses via nuclear recoils due to the lightness of the carbon nucleus. The expected reach for electron recoils is comparable to that of germanium and silicon, with the advantage that dark counts are expected to be under better control. Via absorption processes, unconstrained QCD axion parameter space can be successfully probed in diamond for masses of order 10 eV, further demonstrating the power of our approach.
DS200712-1239
2007
Yu, C.M.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
Yu, C.M.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
DS200912-0744
2009
Yu, C.M.Tang, H.Y., Zheng, J.P., Yu, C.M.Age and composition of the Rushan intrusive complex in the northern Sulu orogen, eastern China: petrogenesis and lithospheric mantle evolution.Geological Magazine, Vol. 146, 2, pp. 199-215.ChinaUHP
DS200912-0859
2009
Yu, C.M.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
DS201212-0826
2012
Yu, C.M.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
DS201312-0151
2013
Yu, C-Q.Chen, W-P., Yu, C-Q., Tseng, T-L., Wang, C-Y.Moho, seismogenesis, and rheology of the lithosphere.Tectonophysics, Vol. 609, pp. 491-503.MantleModels
DS200612-0812
2006
Yu, D.Li, H., Wang, L., Li, C., Hu, D., Yu, D.S wave velocity structure of the lithosphere beneath the western Dabie Mountain, China.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 15, abstract only.ChinaUHP, geophysics - seismics
DS201412-0383
2014
Yu, D.Huang, Q., Yu, D., Xu, B., Hu, W., Ma, Y., Wang, Y., Zhao, Z., Wen, B., He, J., Liu, Z., Tian, Y.Nanotwinned diamond with unprecedented hardness and stability.Nature, Vol. 510, June 12, pp. 250-253.TechnologyDiamond synthetic
DS201112-1166
2011
Yu, F.Zhang, Z.M., Shen, K., Liou, J.G., Dong, X., Wang, W., Yu, F., Liu, F.Fluid rock interactions during UHP metamorphism: a review of the Dabie Sulu orogen, east-central China.Journal of Asian Earth Sciences, Vol. 42, 3, pp. 316-329.ChinaUHP
DS201212-0820
2012
Yu, F.Zhang, Z.M., Shen, K., Liou, J.G., Dong, X., Wang, W., Yu, F., Liu, F.Fluid rock interactions during UHP metamorphism: a review of the Dabie-Sulu orogen, east central China.Journal of Asian Earth Sciences, Vo. 43, 3, pp. 316-329.ChinaUHP
DS201803-0487
2018
Yu, G.Yakovenchuk, V.N., Yu, G., Pakhomovsky, Y.A., Panikorovskii, T.L., Britvin, S.N., Krivivichev, S.V., Shilovskikh, V.V., Bocharov, V.N.Kampelite, Ba3Mg1.5,Sc4(PO4)6(OH)3.4H2O, a new very complex Ba-Sc phosphate mineral from the Kovdor phoscorite-carbonatite complex ( Kola Peninsula) Russia.Mineralogy and Petrology, Vol. 112, pp. 111-121.Russia, Kola Peninsulacarbonatite - Kovdor
DS201610-1872
2016
Yu, H.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.
DS201901-0086
2018
Yu, H.Wang, S., Yu, H., Zhang, Q., Zhao, Y.Absolute plate motions relative to deep mantle plumes.Earth and Planetary Science Letters, Vol. 490, 1, pp. 88-99.Mantlehotspots

Abstract: Advances in whole waveform seismic tomography have revealed the presence of broad mantle plumes rooted at the base of the Earth's mantle beneath major hotspots. Hotspot tracks associated with these deep mantle plumes provide ideal constraints for inverting absolute plate motions as well as testing the fixed hotspot hypothesis. In this paper, 27 observed hotspot trends associated with 24 deep mantle plumes are used together with the MORVEL model for relative plate motions to determine an absolute plate motion model, in terms of a maximum likelihood optimization for angular data fitting, combined with an outlier data detection procedure based on statistical tests. The obtained T25M model fits 25 observed trends of globally distributed hotspot tracks to the statistically required level, while the other two hotspot trend data (Comores on Somalia and Iceland on Eurasia) are identified as outliers, which are significantly incompatible with other data. For most hotspots with rate data available, T25M predicts plate velocities significantly lower than the observed rates of hotspot volcanic migration, which cannot be fully explained by biased errors in observed rate data. Instead, the apparent hotspot motions derived by subtracting the observed hotspot migration velocities from the T25M plate velocities exhibit a combined pattern of being opposite to plate velocities and moving towards mid-ocean ridges. The newly estimated net rotation of the lithosphere is statistically compatible with three recent estimates, but differs significantly from 30 of 33 prior estimates.
DS201911-2555
2019
Yu, H.Qiu, K., Yu, H., Wu, M., Geng, J., Ge, X., Gou, Z., Taylor, R.D.Discrete Zr and REE mineralization of the Baerzhe rare metal deposit, China.American Mineralogist, Vol. 104, pp. 1487-1502.ChinaREE

Abstract: Although REE (lanthanides + Sc + Y) mineralization in alkaline silicate systems is commonly accompanied with Zr mineralization worldwide, our understanding of the relationship between Zr and REE mineralization is still incomplete. The Baerzhe deposit in Northeastern China is a reservoir of REE, Nb, Zr, and Be linked to the formation of an Early Cretaceous, silica-saturated, alkaline intrusive complex. In this study, we use in situ laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analyses of zircon and monazite crystals to constrain the relationship between Zr and REE mineralization at Baerzhe. Three groups of zircon are identified and are differentiated based upon textural observations and compositional characteristics. Type Ia zircons display well-developed oscillatory zoning. Type Ib zircons are darker in cathodoluminescence images and have more irregular zoning and resorption features than type Ia zircons. In addition, type Ib zircons can locally occur as overgrowths on type Ia zircons. Type II zircons contain irregular but translucent cores and rims with oscillatory zoning that are murky brown in color and occur in aggregates. Textural features and compositional data suggest that types Ia and Ib zircon crystallized at the magmatic stage, with type Ia being least-altered and type Ib being strongly altered. Type II zircons, on the other hand, precipitated during the magmatic to magmatichydrothermal transition. Whereas the magnitude of the Eu anomaly is moderate in the barren alkaline granite, both magmatic and deuteric zircon exhibit pronounced negative anomalies. Such features are difficult to explain exclusively by feldspar fractionation and could indicate the presence of fluid induced modification of the rocks. Monazite crystals occur mostly through replacement of zircon and sodic amphibole; monazite clusters are also present. Textural and compositional evidence suggests that monazite at Baerzhe is hydrothermal. Types Ia and Ib magmatic zircon yield 207Pb-corrected 206Pb/238U ages of 127.2 ± 1.3 and 125.4 ± 0.7 Ma, respectively. Type II deuteric zircon precipitated at 124.9 ± 0.6 Ma. The chronological data suggest that the magmatic stage of the highly evolved Baerzhe alkaline granite lasted less than two million years. Hydrothermal monazite records a REE mineralization event at 122.8 ± 0.6 Ma, approximately 1 or 2 million years after Zr mineralization. We therefore propose a model in which parental magmas of the Baerzhe pluton underwent extensive magmatic differentiation while residual melts interacted with aqueous hydrothermal fluids. Deuteric zircon precipitated from a hydrosilicate liquid, and subsequent REE mineralization, exemplified by hydrothermal monazite, correlates with hydrothermal metasomatic alteration that postdated the hydrosilicate liquid event. Such interplay between magmatic and hydrothermal processes resulted in the formation of discrete Zr and REE mineralization at Baerzhe.
DS200612-1552
2005
Yu, H-M.Xia, Q-K., Sheng, Y-M., Yang, X-Z., Yu, H-M.Heterogeneity of water in garnets from UHP eclogites, eastern Dabie Shan, China.Chemical Geology, Vol. 224, 4, Dec. 20, pp. 237-246.ChinaUHP, Bixiling
DS201710-2239
2017
Yu, H-M.Li, W-Y., Huang, F., Yu, H-M., Xu, J., Halama, R., Teng, F-Z.Barium isotopic composition of the mantle constrained by carbonatites.Goldschmidt Conference, 1p. AbstractAfrica, Tanzania, east Africa, Canada, Europe, Germany, Greenlandcarbonatite

Abstract: Deep mantle origin and ultra-reducing conditions in podiform chromitite: diamonds, moissanite, and other unusual minerals in podiform chromitites from the Pozanti-Karsanti ophiolite, southern Turkey
DS201906-1364
2019
Yu, H-M.Zeng, Z., Li, X., Liu, Y., Huang, F., Yu, H-M.High precision barium isotope measurements of carbonates by MC-ICP-MS.Geostandards and Geoanalytical Research, Vol. 43, 2, pp. 291-300.Globalcarbonatites

Abstract: This study presents a high?precision method to measure barium (Ba) isotope compositions of international carbonate reference materials and natural carbonates. Barium was purified using chromatographic columns filled with cation exchange resin (AG50W?X12, 200-400 mesh). Barium isotopes were measured by MC?ICP?MS, using a 135Ba-136Ba double?spike to correct mass?dependent fractionation during purification and instrumental measurement. The precision and accuracy were monitored by measuring Ba isotope compositions of the reference material JCp?1 (coral) and a synthetic solution obtained by mixing NIST SRM 3104a with other matrix elements. The mean ?137/134Ba values of JCp?1 and the synthetic solution relative to NIST SRM 3104a were 0.21 ± 0.03‰ (2s, n = 16) and 0.02 ± 0.03‰ (2s, n = 6), respectively. Replicate measurements of NIST SRM 915b, COQ?1, natural coral and stalagmite samples gave average ?137/134Ba values of 0.10 ± 0.04‰ (2s, n = 18), 0.08 ± 0.04‰ (2s, n = 20), 0.27 ± 0.04‰ (2s, n = 16) and 0.04 ± 0.03‰ (2s, n = 20), respectively. Barium mass fractions and Ba isotopes of subsamples drilled from one stalagmite profile were also measured. Although Ba mass fractions varied significantly along the profile, Ba isotope signatures were homogeneous, indicating that Ba isotope compositions of stalagmites could be a potential tool (in addition to Ba mass fractions) to constrain the source of Ba in carbonate rocks and minerals.
DS201908-1786
2019
Yu, H-M.Li, W-Y., Yu, H-M., Xu, J., Halama, R., Bell, K., Nan, X-Y., Huang, F.Barium isotopic composition of the mantle: constraints from carbonatites.Geochimica et Cosmochimica Acta, in press available doi.org/10.1016 / j.gca.2019.06.041 36p.Africa, Tanzania, Canada, East Africa, Europe, Germany, Greenlanddeposit - Oldoinyo Lengai

Abstract: To investigate the behaviour of Ba isotopes during carbonatite petrogenesis and to explore the possibility of using carbonatites to constrain the Ba isotopic composition of the mantle, we report high-precision Ba isotopic analyses of: (1) carbonatites and associated silicate rocks from the only active carbonatite volcano, Oldoinyo Lengai, Tanzania, and (2) Archean to Cenozoic carbonatites from Canada, East Africa, Germany and Greenland. Carbonatites and associated phonolites and nephelinites from Oldoinyo Lengai have similar ?137/134Ba values that range from +0.01 to +0.03‰, indicating that Ba isotope fractionation during carbonatite petrogenesis is negligible. The limited variation in ?137/134Ba values from ?0.03 to +0.09‰ for most carbonatite samples suggests that their mantle sources have a relatively homogeneous Ba isotopic composition. Based on the carbonatites investigated in this work, the average ?137/134Ba value of their mantle sources is estimated to be +0.04?±?0.06‰ (2SD, n?=?16), which is similar to the average value of +0.05?±?0.06‰ for mid-ocean ridge basalts. The lower ?137/134Ba value of ?0.08‰ in a Canadian sample and higher ?137/134Ba values of +0.14‰ and?+?0.23‰ in two Greenland samples suggest local mantle isotopic heterogeneity that may reflect the incorporation of recycled crustal materials in their sources.
DS202006-0931
2020
Yu, H-M.Li, W-Ye., Yu, H-M., Xu, J., Halama, R., Bell, K., Nan, X-Y., Huang, F.Barium isotopic composition of the mantle: constraints from carbonatites.Geochimica et Cosmochimica Acta, Vol. 278, pp. 235-243. pdfAfrica, Tanzania, Canada, Europe, Germany, Greenlanddeposit - Oldoinyo Lengai

Abstract: To investigate the behaviour of Ba isotopes during carbonatite petrogenesis and to explore the possibility of using carbonatites to constrain the Ba isotopic composition of the mantle, we report high-precision Ba isotopic analyses of: (1) carbonatites and associated silicate rocks from the only active carbonatite volcano, Oldoinyo Lengai, Tanzania, and (2) Archean to Cenozoic carbonatites from Canada, East Africa, Germany and Greenland. Carbonatites and associated phonolites and nephelinites from Oldoinyo Lengai have similar ?137/134Ba values that range from +0.01 to +0.03‰, indicating that Ba isotope fractionation during carbonatite petrogenesis is negligible. The limited variation in ?137/134Ba values from ?0.03 to +0.09‰ for most carbonatite samples suggests that their mantle sources have a relatively homogeneous Ba isotopic composition. Based on the carbonatites investigated in this work, the average ?137/134Ba value of their mantle sources is estimated to be +0.04?±?0.06‰ (2SD, n?=?16), which is similar to the average value of +0.05?±?0.06‰ for mid-ocean ridge basalts. The lower ?137/134Ba value of ?0.08‰ in a Canadian sample and higher ?137/134Ba values of +0.14‰ and?+?0.23‰ in two Greenland samples suggest local mantle isotopic heterogeneity that may reflect the incorporation of recycled crustal materials in their sources.
DS202007-1160
2020
Yu, H-M.Li, W-Y., Yu, H-M., Xu, J., Halama, R., Bell, K., Nan, X-Y., Huang, F.Barium isotopic composition of the mantle: constraints from carbonatites.Geochimica et Cosmochimica Acta, Vol. 278, pp. 235-243.Mantlecarbonatite

Abstract: To investigate the behaviour of Ba isotopes during carbonatite petrogenesis and to explore the possibility of using carbonatites to constrain the Ba isotopic composition of the mantle, we report high-precision Ba isotopic analyses of: (1) carbonatites and associated silicate rocks from the only active carbonatite volcano, Oldoinyo Lengai, Tanzania, and (2) Archean to Cenozoic carbonatites from Canada, East Africa, Germany and Greenland. Carbonatites and associated phonolites and nephelinites from Oldoinyo Lengai have similar ?137/134Ba values that range from +0.01 to +0.03‰, indicating that Ba isotope fractionation during carbonatite petrogenesis is negligible. The limited variation in ?137/134Ba values from ?0.03 to +0.09‰ for most carbonatite samples suggests that their mantle sources have a relatively homogeneous Ba isotopic composition. Based on the carbonatites investigated in this work, the average ?137/134Ba value of their mantle sources is estimated to be +0.04?±?0.06‰ (2SD, n?=?16), which is similar to the average value of +0.05?±?0.06‰ for mid-ocean ridge basalts. The lower ?137/134Ba value of ?0.08‰ in a Canadian sample and higher ?137/134Ba values of +0.14‰ and?+?0.23‰ in two Greenland samples suggest local mantle isotopic heterogeneity that may reflect the incorporation of recycled crustal materials in their sources.
DS201510-1817
2015
Yu, J.Yu, J., LU, R.Color shift and pleochroism in Tanzanite.GSA Annual Meeting, Paper 300-6, 1p. Abstract only BoothTechnologyTanzanite

Abstract: Colored stones are increasingly accepted in China gem market in recent years. Tanzanite owing to its unique violetish blue color is readily recognized and attracts broad attention. Natural, unheated blue tanzanite is known for its trichroic colors in bluish violet, violetish blue, yellow-green. Much lesser known, tanzanite also exhibits metachromatism, a color shift, when illuminated by cold and warm light sources. However, limited existing reports and studies have been mostly descriptive on general gem deposit and basic gemological characteristics. Very little data exit on color shift and pleochroism distinctive to tanzanite. Quantitative analysis on these color characteristics under heating virtually is lacking, even though over 95% tanzanite materials on gem market are reported to have been heated to improve its appearance. This study presents direct observational results on color shift with controlled warm (`3200K) and cold (`6500K) light sources under polarization and known crystallographic orientations. Further quantitative analysis have been performed by polarized spectroscopic measurement on trichroic to dichroic color conversion in tanzanite samples from a set of heating experiments between 650 and 900 °C. Optimal heating temperature for these experiments was determined by thermal analysis (TG-DTA), which showed that tanzanite became unstable above 960 °C. Our optical observation and quantitative results revealed that a yellow-green coloration along the c-crystallographic direction converted and virtually merged into existing blue coloration after heating. Consequently, tanzanite converted from natural, unheated trichroic to heated dichroic.
DS2003-1535
2003
Yu, J.H.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
Yu, J-H.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
Yu, J-H.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
DS200412-2190
2003
Yu, J-H.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
Yu, J-H.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
DS200612-1577
2006
Yu, J-H.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
DS201312-0953
2013
Yu, J-H.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
DS1987-0332
1987
Yu, L.Kapustin, Yu, L.Characteristics of the development of magnesian metasomatism in the early stage calcite carbonatites.(Russian)Zap. Vses. Min. O-Va, (Russian), Vol. 116, No. 1, pp. 28-43RussiaMetasomatism, Carbonatite
DS1994-0877
1994
Yu, L.Kapustin, Yu, L.Geochemistry of kimberlite like rocks from dikes and explosion pipes in carbonatite complexes.Geochemistry International, Vol. 31, No. 6, pp. 27-45.RussiaCarbonatite, Geochemistry
DS200812-1314
2008
Yu, L.Zhang, Y., Bi, H., Yu, L., Sun, S., Qui, J., Xu, C., Wang, H., Wang, R.Evidence for metasomatic mantle carbonatitic magma extrusion in Mesoproterozoic ore hosting dolomite rocks in the middle Kunyang rift, central Yunnan China.Progress in Natural Science, Vol. 18, 8, pp. 965-974.ChinaCarbonatite
DS201412-0996
2014
Yu, L.Xu, Y., Cawood, P., Du, Y., Yu, L., Yu, W., Zhu, Y., Li, W.Linking south Chin a to northern Australia and India on the margin of Gondwana: constraints from detrital zircon U-Pb isotopes in Cambrian strata.Tectonics, Vol. 32, 6, pp. 1547-1558.ChinaGeochronology
DS2003-1555
2003
Yu, L.J.Zhao, Z.Y., Fang, A.M., Yu, L.J.High to ultrahigh pressure ductile shear zones in the Sulu UHP metamorphic belt, China:Terra Nova, Vol. 15, pp. 322-29.ChinaUHP, subduction
DS200412-2220
2003
Yu, L.J.Zhao, Z.Y., Fang, A.M., Yu, L.J.High to ultrahigh pressure ductile shear zones in the Sulu UHP metamorphic belt, China: implications for continental subductionTerra Nova, Vol. 15, pp. 322-29.ChinaUHP, subduction
DS200712-0191
2006
Yu, M.Clark, M.E., Brake, I., Huls, B.J., Smith, B.E., Yu, M.Creating value through application of flotation science and technology. ( mentions BHP diamonds)Minerals Engineering, Vol. 19, 5-6, May-July pp. 758-765.TechnologyMineral processing
DS201412-0377
2014
Yu, Q.Hsu, T., Lucas, A., Qiu, Z., Li, M.,Yu, Q.Exploring the Chinese gem and jewelry industry.Gems & Gemology, Vol. 50, 1, Spring, pp. 2-29.ChinaGemstones - economics
DS201812-2840
2018
Yu, S.Li, Y., Zhang, J., Mustofa, K.M.G., Wang, Y., Yu, S., Cai, Z., Li, P., Zhou, G., Fu, C., Mao, X.Petrogenesis of carbonatites in the Luliangshan region, North Qaidam, northern Tibet, China: evidence for recycling of sedimentary carbonate and mantle metasomatism within a subduction zone.Lithos, Vol. 322, pp. 148-165.China, Tibetcarbonatite

Abstract: Carbonatitic magmatism in subduction zones provides extremely valuable information on the cycling, behavior and storage of deep carbon within the Earth. It may also shed light on insights into crust-mantle interaction and mantle metasomatism within subduction zones. Origin of carbonatite has long been debated: all hypotheses need to reflect the different mineral assemblages and geochemical compositions of carbonatites and their diverse tectonic settings. Here we present a petrological, geochronological, geochemical and isotopic study of carbonatite bodies associated with orogenic peridotites, which occur as stocks or dykes with widths of tens to hundreds of meters in the Luliangshan region, North Qaidam, northern Tibet, China. On the basis of modal olivine (Ol) content, the studied samples were subdivided into two groups: Ol-poor carbonatite and Ol-rich carbonatite. Zircon grains from the Ol-poor carbonatite show detrital features, and yield a wide age spectrum between 400?Ma and 1000?Ma with a pronounced peak at ca. 410-430?Ma. By contrast, oscillatory zoned zircons and inherited cores show two relatively small Neoproterozoic age peaks at ca. 920 and 830?Ma. Zircon grains from the Ol-rich carbonatite sample are also distributed in a wide spectrum between 400 and 1000?Ma, with a pronounced peak at ca. 440?Ma and a slightly inferior peak at ca. 410?Ma. The oscillatory zoned zircons and inherited cores exhibit a smaller Neoproterozoic age peak at ca. 740?Ma. The pronounced peaks ranging from 430 to 410?Ma are consistent with the deep subduction and mantle metasomatic events recorded in associated ultramafic rocks. Both groups of carbonatites are characterized by enrichment of light rare earth elements (LREEs) with high (La/Yb)N values and pronounced negative Eu anomalies. They show high 87Sr/86Sr values (0.708156-0.709004), low 143Nd/144Nd values (0.511932-0.512013) and high ?18OV-SMOW values (+17.9 to +21.3‰). This geochemical and isotopic evidence suggests that these carbonatites were derived from remobilized sedimentary carbonate rocks. We propose that the primary carbonatite magma was formed by partial melting of sedimentary carbonates with mantle contributions. Sedimentary carbonates were subducted into the shallow upper mantle where they melted and formed diapirs that moved upwards through the hot mantle wedge. The case presented provides a rare example of carbonatite originating from sedimentary carbonates with mantle contributions and relevant information on the mantle metasomatism within a subduction zone.
DS1989-1516
1989
Yu, S.C.Tsai, J.W., Yu, S.C.Diamond synthesis from vapors at low pressure conditionsGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A116. (abstract.)GlobalDiamond synthetic
DS1990-1482
1990
Yu, S.C.Tsai, J.W., Yu, S.C.Diamond synthesis from vapours at low pressure conditionsProcess Mineralogy IX: editors, Petruk, W., Hagni, R.D. et al. TMS, No. IX:, pp. 607-614GlobalDiamond synthesis, Diamond crystallography
DS201012-0890
2010
Yu, S.Y.Zhang, J.X., Mattinson, C.G., Yu, S.Y., Li, J.P., Meng, F.C.U-Pb zircon geochronology of coesite bearing eclogites from the southern Dulan areas of the North Qaidam UHP terrane, northwestern China: spatially and temporallyJournal of Metamorphic Geology, Vol. 28, 9, pp. 955-978.ChinaUHP - subduction
DS201312-0539
2013
Yu, T.Liang, Q., Meng, Y., Yan, C., Krasnicki, S., Lai, J., Hemawan, K., Shu,H., Popov, D., Yu,T., Yang, W., Mao, H., Hemley, R.Developments in synthesis, characterization, and application of large high-quality CVD single crystal diamond.Journal of Superhard Materials, Vol. 35, 4, pp. 195-213.TechnologyDiamond synthetics
DS201801-0005
2018
Yu, T.Beyer, C., Rosenthal, A., Myhill, R., Crichton, W.A., Yu, T., Frost, D.J.An internally consistent pressure calibration of geobarometers applicable to the Earth's upper mantle using insitu XRD.Geochimica et Cosmochimica Acta, Vol. 222, Feb 1, pp. 421-435.Mantlegeobarometry

Abstract: We have performed an experimental cross calibration of a suite of mineral equilibria within mantle rock bulk compositions that are commonly used in geobarometry to determine the equilibration depths of upper mantle assemblages. Multiple barometers were compared simultaneously in experimental runs, where the pressure was determined using in-situ measurements of the unit cell volumes of MgO, NaCl, Re and h-BN between 3.6 and 10.4?GPa, and 1250 and 1500?°C. The experiments were performed in a large volume press (LVPs) in combination with synchrotron X-ray diffraction. Noble metal capsules drilled with multiple sample chambers were loaded with a range of bulk compositions representative of peridotite, eclogite and pyroxenite lithologies. By this approach, we simultaneously calibrated the geobarometers applicable to different mantle lithologies under identical and well determined pressure and temperature conditions. We identified discrepancies between the calculated and experimental pressures for which we propose simple linear or constant correction factors to some of the previously published barometric equations. As a result, we establish internally-consistent cross-calibrations for a number of garnet-orthopyroxene, garnet-clinopyroxene, Ca-Tschermaks-in-clinopyroxene and majorite geobarometers.
DS202104-0618
2020
Yu, T.Xu, M., Jing, Z., Bajgain, S.K., Mookherjee, M., Van Orman, J.A., Yu, T., Wang, Y.High pressure elastic properties of dolomite melt supporting carbonate-induced melting in deep upper mantle.Proceedings of the National Academy of Sciences PNAS, Vol. 117, 31, pp. 18285-18291. pdfMantlemelting

Abstract: Deeply subducted carbonates likely cause low-degree melting of the upper mantle and thus play an important role in the deep carbon cycle. However, direct seismic detection of carbonate-induced partial melts in the Earth’s interior is hindered by our poor knowledge on the elastic properties of carbonate melts. Here we report the first experimentally determined sound velocity and density data on dolomite melt up to 5.9 GPa and 2046 K by in-situ ultrasonic and sink-float techniques, respectively, as well as first-principles molecular dynamics simulations of dolomite melt up to 16 GPa and 3000 K. Using our new elasticity data, the calculated VP/VS ratio of the deep upper mantle (?180-330 km) with a small amount of carbonate-rich melt provides a natural explanation for the elevated VP/VS ratio of the upper mantle from global seismic observations, supporting the pervasive presence of a low-degree carbonate-rich partial melt (?0.05%) that is consistent with the volatile-induced or redox-regulated initial melting in the upper mantle as argued by petrologic studies. This carbonate-rich partial melt region implies a global average carbon (C) concentration of 80-140 ppm. by weight in the deep upper mantle source region, consistent with the mantle carbon content determined from geochemical studies.
DS2001-0496
2001
Yu, T.F.Hwang, S.L., Shen, P., Chu, H.T., Yu, T.F., Lin, C.C.Genesis of microdiamonds from melt and associated multiphase inclusions ingarnet of ultra high gneiss ..Earth and Planetary Science Letters, Vol. 188, No. 1, May 30, pp. 9-15.GermanyMicrodiamonds, ultra high pressure (UHP), Erzgebirge
DS200612-0614
2006
Yu, T-F.Hwang, S-L., Shen, P., Chu, H-T., Yu, T-F.A new occurrence and new dat a on akdalaite a retrograde mineral from UHP Whiteschist, Kokchetav Massif, northern Kazakhstan.International Geology Review, Vol. 48, 8, pp. 754-RussiaUHP
DS200512-1224
2005
Yu, W.Yu, W., Wen,L.,Niu, F.Seismic velocity structure in the Earth's outer core.Journal of Geophysical Research, Vol. 110, B2, B02302.MantleGeophysics - seismics
DS200712-1208
2007
Yu, W.Yu, W., Wen, L.Complex seismic anisotropy in the top of the Earth's inner core beneath Africa.Journal of Geophysical Research, Vol. 112, B8, B08304.AfricaGeophysics - seismics
DS201412-0996
2014
Yu, W.Xu, Y., Cawood, P., Du, Y., Yu, L., Yu, W., Zhu, Y., Li, W.Linking south Chin a to northern Australia and India on the margin of Gondwana: constraints from detrital zircon U-Pb isotopes in Cambrian strata.Tectonics, Vol. 32, 6, pp. 1547-1558.ChinaGeochronology
DS200612-1578
2006
Yu, W-C.Yu, W-C., Wen, L.Seismic velocity and attenuation structures in the top 400 km of the Earth's inner core along equatorial paths.Journal of Geophysical Research, Vol. 111, B7 B07308MantleGeophysics - seismics
DS200712-1209
2007
Yu, W-C.Yu, W-C., Wen, L.Complex seismic anisotropy in the top of the Earth's inner core beneath Africa.Journal of Geophysical Research, Vol. 112, B08304.AfricaGeophysics - seismics
DS200512-1225
2003
Yu, X.Yu, X., Mo, X., Liao, Z., Zhao, X., Su, Q.The petrological and mineralogical characteristics of Cenozoic kamafugite and carbonatite association from west Qinling area ( China).Periodico di Mineralogia, (in english), Vol. LXX11, 1. April, pp. 161-179.China, GansuTectonics
DS200612-1601
2006
Yu, X.Zhao, Z., Gautheron, C., Farley, K., Zhang, H., Yu, X., Mo, X.Subcontinental lithospheric mantle origin of the Cenozoic kamafugite in western Qinling, China: evidence from helium isotopes in mantle derived xenoliths.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 16 abstract only.ChinaKamafugite, geochronology
DS200712-0736
2006
Yu, X.Mo, X., Zhao, Z., Deng, J., Flower, M., Yu, X., Luo, Z., Li, Y., Zhou, S., Deng, G., Zhu, D.Petrology and geochemistry of post collisional volcanic rocks from the Tibetan plateau: implications for lithosphere heterogeneity and collision induced mantleGeological Society of America, Special Paper, No. 409, pp. 507-530.AsiaSubduction
DS200812-1280
2008
Yu, X.Xu, C., Qi, L., Huang, Z., Chen, Y., Yu, X., Wang, L., Li, E.Abundances and significance of platinum group elements in carbonatites from China.Lithos, in press available, 7p.ChinaCarbonatite
DS200812-1300
2008
Yu, X.Yu, X., Zhao, Z., Mo, X., Dong, G.Cenozoic alkaline and carbonatitic magmatism in northeastern Tibetan Plateau: implications for mantle plume.Goldschmidt Conference 2008, Abstract p.A1065.Asia, TibetCarbonatite
DS200912-0844
2009
Yu, X.Yu, X., Mo, X., Zhao, Z.Two types of Cenozoic potassic volcanic rocks and carbonatite and their geodynamic implications in western Qinling, NW China.Goldschmidt Conference 2009, p. A1491 Abstract.ChinaCarbonatite
DS201312-0346
2014
Yu, X.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
Yu, X.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
DS202103-0385
2020
Yu, X.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.
DS202205-0735
2022
Yu, X.Yu, X., Liu, F., Long, Z-Y.Li, H.B., Wang, H., Yu, X-Y.Color genesis of brown diamond from the Mengyin kimberlite, China.Crystals, March 23p.Chinadeposit - Mengyin

Abstract: The Mengyin diamondiferous kimberlite cluster in Shandong province is one of the three major sources of natural diamond in China, where many brown diamonds are mined, but the genesis of their color is still controversial. In this paper, studies including microscopic examination, optical properties of orthogonal polarization, low temperature photoluminescence spectra, infrared spectra, Raman spectra, ultraviolet-visible absorption spectra, luminescence of cathodoluminescence, and transmission electron microscopy have been carried out on the uncut brown diamonds and their slice samples to constrain on the color genesis of brown diamond from the Mengyin deposit. The results show that the brown color is dominantly caused by plastic deformation, and some samples are also caused by non-deformation-related defects and inclusions.
DS202110-1624
2021
Yu, X-Y.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.
DS202205-0735
2022
Yu, X-Y.Yu, X., Liu, F., Long, Z-Y.Li, H.B., Wang, H., Yu, X-Y.Color genesis of brown diamond from the Mengyin kimberlite, China.Crystals, March 23p.Chinadeposit - Mengyin

Abstract: The Mengyin diamondiferous kimberlite cluster in Shandong province is one of the three major sources of natural diamond in China, where many brown diamonds are mined, but the genesis of their color is still controversial. In this paper, studies including microscopic examination, optical properties of orthogonal polarization, low temperature photoluminescence spectra, infrared spectra, Raman spectra, ultraviolet-visible absorption spectra, luminescence of cathodoluminescence, and transmission electron microscopy have been carried out on the uncut brown diamonds and their slice samples to constrain on the color genesis of brown diamond from the Mengyin deposit. The results show that the brown color is dominantly caused by plastic deformation, and some samples are also caused by non-deformation-related defects and inclusions.
DS1996-0685
1996
Yu, Y.Jian, X., Olea, R.A., Yu, Y.Semivariogram modeling by weighted least squaresComputers and Geosciences, Vol. 22, No. 4, pp. 379-386GlobalComputer, Program -semi variograM.
DS200512-0413
2004
Yu, Y.Hearn, T.M., Wang, S., Ni, J.F., Xu, Z., Yu,Y., Zhang, X.Uppermost mantle velocities beneath Chin a and surrounding regions.Journal of Geophysical Research, Vol. 109, 11, DOI 10:1029/2003 JB002874ChinaGeophysics - seismics
DS200812-1282
2008
Yu, Y.Xu, W-L., Yang, D.B., Gao, S., Yu, Y., Pei, F.P.Mesozoic lithospheric mantle of the Central North Chin a craton: evidence from peridotite xenoliths.Goldschmidt Conference 2008, Abstract p.A1047.ChinaXenoliths
DS201012-0838
2010
Yu, Y.Wei, C.J., Li, J., Yu, Y., Zhang, J.S.Phase equilibration temperatures and metamorphic evolution of glaucophane bearing UHP eclogites from the western Dabie Shan terrane, central China.Journal of Metamorphic Geology, Vol. 28, 6, pp. 647-666.ChinaUHP
DS201512-1997
2015
Yu, Y.Yu, Y., Liu, K.H., Reed, C.A., Moidaki, M., Mickus, K., Atekwana, E.A., Gao, S.S.A joint receiver function and gravity study of crustal structure beneath the incipient Okavango Rift, Botswana.Geophysical Research Letters, Vol. 42, 20, pp. 8398-8405.Africa, BotswanaGeophysics - gravity

Abstract: Rifting incorporates the fundamental processes concerning the breakup of continental lithosphere and plays a significant role in the formation and evolution of sedimentary basins. In order to decipher the characteristics of rifting at its earliest stage, we conduct the first teleseismic crustal study of one of the world's youngest continental rifts, the Okavango Rift Zone (ORZ), where the magma has not yet breached the surface. Results from receiver function stacking and gravity modeling indicate that the crust/mantle boundary beneath the ORZ is uplifted by 4-5 km, and the initiation of the ORZ is closely related to lithospheric stretching. Possible decompression melting of the subcrustal lithosphere occurs beneath the ORZ, as evidenced by a relatively low upper mantle density based on the gravity modeling.
DS202105-0802
2021
Yu, Y.Yu, Y., Huang, X-L., Sun, M., Ma, J-L.B isotopic constraints on the role of H2O in mantle wedge melting.Geochimica et Cosmochimica Acta, Vol. 303, pp. 92-109, pdfMantlemelting

Abstract: The role of water on melting in the mantle wedge is still debated due to large uncertainty on the estimates of H2O flux beneath arcs. B has been proven as an effective proxy for water flux because B and H2O show similar chemical behaviors during subduction. The Habahe mafic dikes from the Chinese Altai were emplaced within a narrow area (<20?km from south to north) during the northward subduction of the Junggar Ocean in the middle Paleozoic. These dikes have been classified into four types with distinct geochemical and Sr-Nd-Hf-Pb isotopic compositions, which originated from mantle sources metasomatized by different subduction components, including melts from subducted sediments (Type-I, Type-IV), fluids from subducted sediments (Type-II), and melts from subducted oceanic crust (Type-III). We present B content and isotope data for the Habahe mafic dikes to investigate the influence of subduction components on melting in the mantle wedge. Type-I and -III mafic dikes all have negative ?11B values (?7.7‰ to ?5.0‰) with variable B contents (3.65-13.4?ppm) and B/Nb ratios (2.10-7.39), indicating B isotopically light features for the subducted sediments and oceanic crust. Type-II mafic dikes have lower B contents (3.97-9.90?ppm) and higher B/Nb ratios (7.07-14.4) than Type-I mafic dikes, with a wide range of ?11B values from ?7.8‰ to ?2.7‰. This suggests that their mantle source may have been metasomatized by fluids from subducted serpentinite besides fluids from subducted sediments. Type-IV mafic dikes have higher B contents (17.0-27.5?ppm) and B/Nb ratios (25.0-40.8), and heavier B isotopic compositions (?11B?=??2.9‰ to +3.5‰) than Type-I mafic dikes. This indicates involvement of fluids from the slab serpentinite in metasomatism of their mantle source in addition to melts from the subducted sediments. The Habahe mafic dikes show wide range of B/Nb ratios, suggesting that different amounts of water were added into their mantle sources. These dikes exhibit variable Zr/Yb and Nb/Yb ratios, and constantly low TiO2/Yb, indicating their formation through different degrees melting of depleted mantle sources. Their Zr/Yb and Nb/Yb ratios are negatively correlated with B/Nb, which reflects elevation of the melting degree of their mantle sources as increasing water input. Similar trends are also observed in basalts from global arcs and their major and trace elements correlate well with B/Nb ratios. Thus, water flux should play an important role on melting in the mantle wedge and control magma compositions of the arcs.
DS201112-1144
2011
Yu, Y.G.Yu, Y.G., Wentzcovitch, R.M., Vinograd, V.L., Angel, R.J.Thermodynamic properties of MgSiO3 majorite and phase transitions near 660 km depth in MgSiO3 and Mg2SiO4: a first principles study.Journal of Geophysical Research, Vol. 116, B02208 ( 19p)MantleThermodynamics
DS201212-0743
2012
Yu, Y.G.Valdez, M.N., Wu, Z., Yu, Y.G., Revenaugh,J., Wentzcovitch, R.M.Thermoeleastic properties of ringwoodite: its relationship to the 520 seismic discontinuity.Earth and Planetary Science Letters, Vol. 351-352, pp. 115-122.MantleGeophysics - seismics
DS1992-1726
1992
Yu XuehuiYu XuehuiMantle metasomatism and its fluids in western Qinling, Gansu: evidence from mantle xenoliths and gluboles in alkaline ultrabasic volcanic rocksInternational Symposium Cenozoic Volcanic Rocks Deep seated xenoliths China and its, Abstracts pp. 12-14ChinaMantle, Xenoliths
DS1994-1095
1994
Yu.A.Maltsev, K.A.Klyuyev, Yu.A.Nitrogen aggregation in diamonds and diamond formationGeochemistry International, Vol. 31, No. 4, pp. 99-102.GlobalDiamond genesis, Nitrogen
DS2000-0755
2000
Yu.M.Perchuk, L.L., Gerya, T.V., Yu.M.Comparative petrology and metamorphic evolution of the Limpopo (South Africa) and Lapland ( Fennoscandia)...Min. Petrol., Vol. 69, No. 1-2, pp. 69-108.South Africa, Scandinavia, LaplandHigh grade terrains - comparison, Petrology, metamorphism
DS200712-0347
2007
YuanGao, S., Rudnick, R.L., Xu, W-L., Yuan, Liu, Puchtel, Liu, Huang, WangRecycling deep cratonic lithosphere and generation of intraplate magmatism.Plates, Plumes, and Paradigms, 1p. abstract p. A307.ChinaAlkaline rocks, picrites
DS200812-0385
2008
YuanGao, S., Rudnick, R.L., Xu, Yuan, Liu, Walker, Puchtel, Liu, Huang, Wang, WangRecycling deep cratonic lithosphere and generation of intraplate magmatism in the North Chin a Craton.Earth and Planetary Science Letters, Vol. 270, 1-2, June 15, pp. 41-53.ChinaTectonics - delamination, picrites
DS200812-1172
2008
YuanTian, S., Hou, Ding, Yang, Yang, Yuan, Xie, Liu, Li.Ages of carbonatite and syenite from the Mianning Dechang REE belt in eastern Indo-Asian collision zone, SW Chin a and their geological significance.Goldschmidt Conference 2008, Abstract p.A947.ChinaCarbonatite
DS1989-0655
1989
Yuan, B.Holm, R.G., Jackson, R.D., Yuan, B.Surface reflectance factor retrieval from thematic mapper dataRemote Sensing Environ, Vol. 27, pp. 47-57. Database # 17792GlobalRemote Sensing, TEM.
DS201012-0137
2010
Yuan, B.Das Sharma, S., Ramesh, D.S., Li, X., Yuan, B., Sreenivas, B., Kind, R.Response of mantle transition zone thickness to plume bouyancy flux.Geophysical Journal International, Vol. 180, 1, pp. 49-58.MantlePlume
DS202001-0019
2019
Yuan, C.Huang, Z., Yuan, C., Long, X., Zhang, Y., Du, L.From breakup of Nuna to assembly of Rodinia: a link between the Chinese central Tianshen block and Fennoscandia.Tectonics, Doi.org/10.1029/ 2018TC005471China, Europe, Fennoscandiageochronology

Abstract: The transition from breakup of Nuna (or Columbia, 2.0-1.6 Ga) to assembly of Rodinia (1.0-0.9 Ga) is investigated by means of U?Pb and Lu?Hf data of detrital zircons from three Neoproterozoic metasedimentary rocks in the Central Tianshan Block (CTB), NW China. These data yield six age peaks around 1.0, 1.13, 1.34, 1.4-1.6, 1.75, and 2.6 Ga. Few zircons are detected between 2.0 and 2.5 Ga. The Paleoproterozoic to Neoproterozoic detrital zircons have Hf isotopic compositions (?22.1 to +13.0) similar to those of coeval magmatic rocks in the CTB, indicating a proximal provenance. These results, together with the geological evidence and the presence of 1.4 Ga orogenic granitoids in the CTB, rule out most cratons as the CTB sources but support a Fennoscandia ancestry. Zircon U?Pb ages and Hf isotopic compositions from the CTB and Fennoscandia suggest that from 1.8 to 1.4 Ga, the ?Hf(t) values increased toward more positive values, consistent with an exterior orogen characteristic that the lower crust was replaced by a juvenile arc crust. In contrast, from 1.4 to 0.9 Ga, zircon ?Hf(t) values decreased to more negative values, reflecting an interior orogen, characterized by enhanced contribution of recycled crustal material from collided continental fragments. This marked shift most likely reflected a transition from breakup of Nuna to assembly of Rodinia, accomplished by a transformation from an exterior orogen to an interior one.
DS2001-0275
2001
Yuan, H.Dueker, K., Yuan, H., Zurek, B.Thick structured Proterozoic lithosphere of the Rocky Mountain regionGsa Today, Dec. pp. 4-9.Colorado PlateauTectonics, tomography, seismics
DS2002-1764
2002
Yuan, H.Yuan, H., Dueker, K.Upper mantle tomographic VP and VS images of the Middle Rocky Mountains in Wyoming, Colorado and New Mexico: evidence for a thick heterogeneous chemical lithosphereGeological Society of America Annual Meeting Oct. 27-30, Abstract p. 473.Wyoming, Colorado, New MexicoTomography
DS200412-0489
2004
Yuan, H.Duecker, K., Yuan, H.Upper mantle P wave velocity structure from PASSCAL teleseismic transects across Idaho, Wyoming and Colorado.Geophysical Research Letters, Vol. 31, 8, April 28, DO 10.1029/2004 GLO19476United States, WyomingGeophysics - seismics
DS200412-1165
2004
Yuan, H.Liu, Y., Gao, S., Yuan, H., Zhou, L., Liu, X., Wang, X., Hu, Z., Wang, L.U Pb zircon ages and Nd, Sr, and Pb isotopes of lower crustal xenoliths from North Chin a Craton: insights on evolution of lowerChemical Geology, Vol. 211, 1-2, Nov. 8, pp. 87-109.ChinaGeochronology
DS200512-0651
2005
Yuan, H.Liu, Y., Gao, S., Lee, C.T.A., Hu, S., Liu, X.,Yuan, H.Melt peridotite interactions: links between garnet pyroxenite and high Mg# signature of continental crust.Earth and Planetary Science Letters, Vol. 234, pp. 39-57.MantleGeochemistry
DS200512-1226
2005
Yuan, H.Yuan, H., Dueker, K.Upper mantle tomographic Vp and Vs images of the Rocky Mountains in Wyoming, Colorado, New Mexico: evidence for a thick heterogeneous chemical lithosphere.American Geophysical Union, Geophysical Monograph, No. 154, pp. 329-346.United States,Wyoming, Colorado PlateauGeophysics - seismics, tectonics
DS200612-0830
2006
Yuan, H.Liu, X., Gao, S., Ling, W., Yuan, H., Hu, Z.Identification of 3.5 Ga detrital zircons from Yangtze Craton in South Chin a and the implication for Archean crust evolution.Progress in Natural Science, Vol. 16, 6, June pp. 663-666.ChinaGeochronology
DS201012-0882
2010
Yuan, H.Yuan, H., Romanowicz, B.Lithospheric layering in the North American craton.Nature, Vol. 466, August 26, pp. 1063-1068.United StatesGeophysics
DS201112-0611
2011
Yuan, H.Liu, J., Rudnick, R.L., Walker, R.J., Gao, S., Wu, F-y., Piccoli, P.M., Yuan, H., Xu, W-l., Xu, Yi-G.Mapping lithospheric boundaries using Os isotopes of mantle xenoliths: an example from the North Chin a Craton.Geochimica et Cosmochimica Acta, Vol. 75, 13, pp. 3881-3902.ChinaGeochronology
DS201112-1123
2011
Yuan, H.Wu, Y., Gao, S., Liu, X., Wang, J., Peng, M., Gong, H., Yuan, H.Two stage exhumation of the ultrahigh pressure metamorphic rocks from the Western Dabie Orogen, central China.Journal of Geology, Vol. 119, pp. 15-32.ChinaUHP
DS201112-1124
2011
Yuan, H.Wu, Y., Gao, S., liu, X., Wang, J., peng, M., Gong, H., Yuan, H.Two stage exhumation of ultrahigh pressure metamorphic rocks from the western Dabie orogen, Central China.Journal of Geology, Vol. 119, 1, Jan. pp. 15-31.ChinaUHP
DS201112-1125
2011
Yuan, H.Wu, Y., Gao, S., Liu, X., Wang, J., Peng, M., Gong, H., Yuan, H.Two stage exhumation of ultrahigh pressure metamorphic rocks from the western Dabie Orogen, central China.Journal of Petrology, Vol. 119, no. 1, pp. 15-31.ChinaUHP
DS201112-1145
2010
Yuan, H.Yuan, H., Romanowicz, B.Depth dependent azimuthal anisotropy in the western US upper mantle.Earth and Planetary Science Letters, Vol. 300, 3-4, pp. 385-394.United StatesGeophysics - seismics
DS201112-1146
2011
Yuan, H.Yuan, H., Romanowicz, B., Fischer, K., Abt, D.3-D shear wave radially and azimuthally anisotropic velocity model of the North American upper mantle.Geophysical Journal International, in press Jan. 17Canada, United StatesGeophysics - seismics
DS201312-0047
2013
Yuan, H.Bader, T., Ratschbacher, L., Franz, L., Yang, Z., Hofmann, M., Linneman, U., Yuan, H.The heart of Chin a revisited. 1. Proterozoic tectonics of the Qin Mountains in the core of supercontinent Rodinia.Tectonics, Vol. 32, 3, pp. 661-687.ChinaMagmatism - Dabie orogen
DS201312-1001
2013
Yuan, H.Yuan, H.Anisotropic velocity model of North America.GEM Diamond Workshop Feb. 21-22, Noted onlyCanadaGeophysics - seismics
DS201412-0249
2014
Yuan, H.Foster, K., Dueker, K., Schmandt, B., Yuan, H.A sharp cratonic lithosphere-asthenosphere boundary beneath the American Midwest and its relation to mantle flow.Earth and Planetary Science Letters, Vol. 402, pp. 82-89.United States, Colorado PlateauGeophysics - seismics
DS201412-1012
2014
Yuan, H.Yuan, H., French, S., Cupillard, P., Romanowicz, B.Lithospheric expression of geological units in central and eastern North America from full waveform tomography.Earth and Planetary Science Letters, Vol. 402, pp. 176-186.United StatesGeophysics - seismics
DS201511-1891
2015
Yuan, H.Yuan, H.Secular changes in Archean crust formation recorded in western Australia.Nature Geoscience, Vol. 8, 10, pp. 808-813.AustraliaGeophysics - seismics, subduction

Abstract: The formation mechanisms for early Archaean continental crust are controversial. Continental crust may have accumulated via horizontal accretion in modern-style subduction zones or via vertical accretion above upper mantle upwelling zones. However, the characteristics of the continental crust changes at the transition between the Archaean and Proterozoic eons, suggesting that continental crust did not form in subduction zones until at least the late Archaean. Here I use seismic receiver function data to analyse the bulk properties of continental crust in Western Australia, which formed and stabilized over a billion years in the Archaean. I find that the bulk seismic properties of the crust cluster spatially, with similar clusters confined within the boundaries of tectonic terranes. I use local Archaean crustal growth models to show that both plume and subduction processes may have had a role in creating crust throughout the Archaean. A correlation between crustal age and the bulk seismic properties of the crust reveals a trend: from about 3.5?Gyr ago (Ga) to the end of the Archaean, the crust gradually thickened and simultaneously became more evolved in composition. I propose that this trend reflects the transition between crust dominantly formed above mantle plumes, to crust formed in subduction zones-a transition that may reflect secular cooling of Earth’s mantl
DS201807-1539
2018
Yuan, H.Yuan, H., Bodin, T.A probabilistic shear wave velocity model of the crust in the central west Australian craton constrained by transdimensional inversion of ambient noise dispersion.Tectonics, June 12, DOI: 10.129/ 2017TC004834Australiageophysics - seismic

Abstract: The Capricorn Orogen in central Western Australia played important roles in initializing and finalizing the West Australian craton. Surface geological mapping and isotopic studies show that the crust has recorded over a billion years of tectonic history spanning from its crustal formation in the Archean to episodes of tectono?thermal events during the Proterozoic cratonization processes. The region therefore provides us with an ideal laboratory to characterize the seismic signature associated with tectonic processes. We constructed a crustal shear?wave velocity model of the core region of the orogen, the Glenburgh Terrane and its north boundary, by inverting the array group velocity dispersion data measured from a high density temporary array. A modified Bayesian Transdimensional tomography technique, which incorporates a smooth?varying regional reference velocity model and Moho topography, was used to invert for the crustal velocity variations. The inverted velocity model adds great detail to the intra?crustal structure, and provides complementary seismic velocity information to refine the regional tectonic processes. Distinct patterns in the velocity structure support that the Glenburgh Terrane is a microcontinent originated in the Archean, and favor the operation of Paleoproterozoic subduction/accretion leading to the 2.2 Ga Ophthalmian orogeny that initiated the assembly of the West Australian craton.
DS202002-0220
2019
Yuan, H.Xu, R., Liu, Y., Wang, X-C, Foley, S.F., Zhang, Y., Yuan, H.Generation of continental intraplate alkali basalts and deep carbon cycle.Earth Science Reviews, in press available, 38p. Doi.org/1010.1016 /jearsciev.2019.103073Globalcarbon

Abstract: Although the deep recycling of carbon has been proposed to play a key role in producing intraplate magmatism, the question of how it controls or triggers mantle melting remains poorly understood. In addition, generation of incipient carbonated melts in the mantle and their subsequent reaction with the mantle are critical processes that can influence the geochemistry of intraplate basalts, but the details of such processes are also unclear. Here we present geochemical evidence for the existence of pervasive carbonate melt in the mantle source of Cenozoic continental intraplate highly alkali basalts (SiO2 < 45 wt%), which are volumetrically minor but widespread in eastern China. The primary magma compositions of these basalts cannot be explained by either partial melting of a single mantle source lithology or mixing of magmas derived from distinct mantle sources, but can be adequately explained by carbonate-fluxed melting of eclogite and subsequent reaction between silica-rich melts and peridotite that ultimately transformed the initial carbonated silica-rich melts into silica-undersaturated alkalic magmas. The source of the carbonate is in subducted eclogites associated with the Pacific plate, which stagnated in the mantle transition zone (MTZ). The spatial distribution of the alkali basalts is in accord with large-scale seismic low-velocity anomalies in the upper mantle above the MTZ. Similar scenarios in central-western Europe and eastern Australia lead us to propose that reaction between carbonated silica-rich melt and peridotite may be a pivotal mechanism for the generation of continental intraplate alkali basalts elsewhere in the world.
DS202202-0228
2022
Yuan, H.Zhao, L., Tyler, I.M., Gorczk, W., Murdie, R.E., Gessner, K., Lu, Y., Smithies, H., Lia, T., Yang, J., Zhan, A., Wan, B., Sun, B., Yuan, H.Seismic evidence of two cryptic sutures in northwestern Australia: implications for the style of subduction during the Paleoproterozoic assembly of Columbia.Earth and planetary Science Letters, Vol. 579, 117343, 11p. PdfAustraliageophysics- seismics

Abstract: Plate tectonics, including rifting, subduction, and collision processes, was likely to have been different in the past due to the secular cooling of the Earth. The northeastern part of the West Australian Craton (WAC) has a complex Archean and Paleoproterozoic tectonic history; therefore, it provides an opportunity to study how subduction and collision processes evolved during the emergence of plate tectonics, particularly regarding the assembly of Earth's first supercontinent, Columbia. Because the northeastern boundary of the WAC and the southwestern boundary of the North Australian Craton (NAC) are covered by the Phanerozoic Canning Basin, the regional tectonic evolution has remained enigmatic, including how many tectonic elements were assembled and what may have driven rifting and subsequent collision events. Here, we use new passive-source seismic modeling to identify a seismically distinct segment of the lithosphere, the Percival Lakes Province, which lies east of the Pilbara Craton and is separated by two previously unknown southeast-trending lithosphere scale Paleoproterozoic sutures. We interpret that the northeastern suture, separates the Percival Lakes Province from the NAC, records the amalgamation of the WAC with the NAC. The southwestern suture separates the PLP from the reworked northeastern margin of the Pilbara Craton, including the East Pilbara Terrane and the Rudall Province. A significant upper mantle dipping structure was identified in the southwestern suture, and we interpret it to be a relic of subduction that records a previously unknown Paleoproterozoic collision that pre-dated the amalgamation of the WAC and NAC. By comparing our findings with previously documented dipping features, we show that the Paleoproterozoic collisions are seismically distinguishable from their Phanerozoic counterparts.
DS200512-0313
2004
Yuan, H.L.Gao, S., Rudnick, R.L., Yuan, H.L., Liu, X.M., Liu, Y.S., Xu, W.L., Ling, W.L., Ayers, K., Wang, X.C.,Wang, Q.H.Recycling lower continental crust in the North Chin a Craton.Nature, No. 7019, Dec. 16, pp. 892-896.ChinaSubduction
DS200612-0428
2006
Yuan, H.L.Gao, S., Rudnick, R.L., Xu, W.L., Yuan, H.L., Hu, Z.C., Liu, X.M.Lithospheric evolution of the North Chin a Craton: evidence from high Mg adakitic rocks and their entrained xenoliths.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 193, abstract only.ChinaGeochemistry
DS200612-1579
2006
Yuan, H.L.Yuan, H.L., Gao, S., Rudnick, R.L., Jin, Z.M., Walker, R.J.Re Os evidence for age and origin of peridotites from the Dabie Sulu UHP belt.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 10. abstract only.ChinaUHP, geochronology
DS200612-1547
2006
Yuan, H-L.Wu, F-Y., Walker, R.J., Yang, Y-H., Yuan, H-L., Yang, J-H.The chemical temporal evolution of lithospheric mantle underlying the North Chin a Craton.Geochimica et Cosmochimica Acta, Vol. 70, 19, pp. 5013-5034.ChinaDeposit - Tieling, Fuxian, Mengyin - geochemistry -SCLM
DS200712-1184
2007
Yuan, H-L.Wu, Y-B., Gao, S., Zhang, H-F., Wang, S-H., Jiao, W-F., Liu, Y-S, Yuan, H-L.Timing of UHP metamorphism in the Hongan area, western Dabie Mountains China: evidence from zircon Pb age, trace element and Hf isotope composition.Contributions to Mineralogy and Petrology, Vol. 155, 1, pp. 123-133.ChinaUHP
DS201112-1099
2011
Yuan, H-L.Wang, H., Wu, Y-B., Gao, S., Liu, X-C., Gong, H-J., Li, Q-L., Li, X-H., Yuan, H-L.Eclogite origin and timing in the North Qinling terrane, and their bearing on the amalgamation of the South and North Chin a blocks.Journal of Metamorphic Geology, in press available,ChinaCraton
DS200512-0589
2005
Yuan, I.Kumar, 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
DS200612-1580
2006
Yuan, J.C.C.Yuan, J.C.C., Peng, M-S., Meng, Y-f.Investigation by synchrotron X ray diffraction topography of the crystal structure defects in colored diamonds ( natural, synthetic and treated).GIA Gemological Research Conference abstract volume, Held August 26-27, p. 24. 1/2p.TechnologyX-ray diffraction
DS201312-1002
2013
Yuan, K.Yuan, K., Beghein, C.Seismic anisotropy changes across upper mantle phase transitions.Earth and Planetary Science Letters, Vol. 374, pp. 132-144.MantleDeep water cycle
DS201911-2534
2019
Yuan, L.Ishi, T., Huang, R., Myhill, R., Fei, H., Koemets, I., Liu, Z., Maeda, F., Yuan, L., Wang, L., Druzhbin, D., Yamamoto, T., Bhat, S., Farla, R., Kawazoe, T., Tsujino, N., Kulik, E., Higo, Y., Tange, H., Katsura, T.Sharp 660 km discontinuity controlled by extremely narrow binary post-spinel transition.Nature Geosciences, Vol. 12, pp. 869-872.Mantlediscontinuity

Abstract: The Earth’s mantle is characterized by a sharp seismic discontinuity at a depth of 660?km that can provide insights into deep mantle processes. The discontinuity occurs over only 2?km—or a pressure difference of 0.1?GPa—and is thought to result from the post-spinel transition, that is, the decomposition of the mineral ringwoodite to bridgmanite plus ferropericlase. Existing high-pressure, high-temperature experiments have lacked the pressure control required to test whether such sharpness is the result of isochemical phase relations or chemically distinct upper and lower mantle domains. Here, we obtain the isothermal pressure interval of the Mg-Fe binary post-spinel transition by applying advanced multi-anvil techniques with in situ X-ray diffraction with the help of Mg-Fe partition experiments. It is demonstrated that the interval at mantle compositions and temperatures is only 0.01?GPa, corresponding to 250?m. This interval is indistinguishable from zero at seismic frequencies. These results can explain the discontinuity sharpness and provide new support for whole-mantle convection in a chemically homogeneous mantle. The present work suggests that distribution of adiabatic vertical flows between the upper and lower mantles can be mapped on the basis of discontinuity sharpness.
DS202108-1276
2021
Yuan, Q.Chen, W., Lu, X.B., Cao, X.F., Yuan, Q., Wang, D.Genetic and ore forming ages of Fe-P-(Ti) oxide deposits associated with mafic-ultramafic-carbonatite complexes in the Kuluketage block, NW China.Australian Journal of Earth Sciences, Vol. 66, 7, pp. 1041-1062.Chinacarbonatite

Abstract: During the past 50 years, many geological and ore-deposit investigations have led to the discovery of the Fe-P-(Ti)-oxide deposits associated with mafic-ultramafic-carbonatite complexes in the Kuluketage block, northeastern Tarim Craton. In this paper, we discuss the genetic and ore-forming ages, tectonic setting, and the genesis of these deposits (Kawuliuke, Qieganbulake and Duosike). LA-ICP-MS zircon U-Pb dating yielded a weighted mean 206Pb/238U ages of 811?±?5?Ma, 811?±?4?Ma, and 840?±?5?Ma for Kawuliuke ore-bearing pyroxenite, Qieganbulake gabbro and Duosike ore-bearing pyroxenite, respectively. The CL images of the Kawuliuke apatite grains show core-rim structure, suggesting multi-phase crystallisation, whereas the apatite grains from Qieganbulake and Dusike deposits do not show any core-rim texture, suggesting a single-stage crystallisation. LA-ICP-MS apatite 207Pb-corrected U-Pb dating provided weighted mean 206Pb/238U ages of 814?±?21?Ma and 771?±?8?Ma for the Kawuliuke ores, and 810?±?7?Ma and 841?±?7?Ma for Qieganbulake and Duosike ores, respectively. The core-rim texture in apatite by CL imaging as well as two different ore-forming ages in the core and rim of the apatite indicate two metallogenic events for the Kawuliuke deposit. The first metallogenic period was magmatic in origin, and the second period was hydrothermal in origin. The initial ore-forming age of the Kawuliuke Fe-P-Ti mineralisation was ca 814?Ma and the second one was ca 771?Ma. On the other hand, the ore-forming ages of the Qieganbulake and Duosike deposits were ca 810?Ma and ca 841?Ma, respectively. Qieganbulake and Duosike deposits were of magmatic origin. Combined with previous geochronological data and the research on the tectonic background, we infer that the Kawuliuke, Qieganbulake and Duosike Fe-P-(Ti)-oxide deposits were formed in a subduction-related tectonic setting and were the product of subduction-related magmatism.
DS201312-0405
2013
Yuan, S.Hua, C., Zhili, Q., Taijin, L., Stern, R., Stachel, T., Yuan, S., Jian, Z., Jie, K., Shyu, P., Shecai, Q.Variations in carbon isotopic composition in the subcontinental lithospheric mantle beneath the Yangtze and North Chin a cratons; evidence from in-situ analysis of diamonds using SIMS.Chinese Science Bulletin, Vol. 58, 1, pp. 99-107ChinaCraton
DS2002-0850
2002
Yuan, X.Kind, R., Yuan, X., Saul, J., Nelson, D., Sobolev, S.V., Mechie, J., Zhao, W.Seismic images of crust and upper mantle beneath Tibet: evidence for Eurasian plateScience, No. 5596, pp. 1219-1221.Mantle, ChinaGeophysics - seismics
DS2002-1303
2002
Yuan, X.Ramesh, D.S., Kind, R., Yuan, X.Receiver function analysis of the North American crust and upper mantleGeophysical Journal International, Vol.150,1,pp.91-108.MantleGeophysics - seismics
DS2003-0811
2003
Yuan, X.Li, X., Kind, R., Yuan, X.Seismic study of upper mantle and transition zone beneath hotspotsPhysics of the Earth and Planetary Interiors, Vol. 136, 1-2, pp. 79-82.MantleBlank
DS2003-0812
2003
Yuan, X.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
DS2003-0813
2003
Yuan, X.Li, X., Yuan, X.Receiver functions in northeast Chin a - implications for slab penetrations into the lowerEarth and Planetary Science Letters, Vol. 216, 4, pp. 679-691.ChinaGeophysics - seismics
DS200412-1129
2003
Yuan, X.Li, X., Kind, R., Yuan, X.Seismic study of upper mantle and transition zone beneath hotspots.Physics of the Earth and Planetary Interiors, Vol. 136, 1-2, pp. 79-82.MantleGeophysics - seismics
DS200412-1130
2003
Yuan, X.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
DS200412-1131
2003
Yuan, X.Li, X., Yuan, X.Receiver functions in northeast Chin a - implications for slab penetrations into the lower mantle.Earth and Planetary Science Letters, Vol. 216, 4, pp. 679-691.ChinaGeophysics - seismics
DS200612-1332
2006
Yuan, X.Sodoudi, F., Yuan, X., Liu, Q., Chen, J.K.Lithospheric thickness beneath the Dabie Shan, central eastern Chin a from S receiver functions.Geophysical Journal International, Vol. 166, 3, pp. 1362-1367.ChinaGeophysics - seismics, UHP
DS200712-0623
2007
Yuan, X.Li, X., Yuan, X., Kind, R.The lithosphereasthenosphere boundary beneath the western United States.Geophysical Journal International, Vol. 170, 2, pp. 700-710.United StatesGeophysics - seismics
DS200912-0197
2009
Yuan, X.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
DS201412-0864
2013
Yuan, X.Sodoudi, F., Yuan, X., Kind, R., Lebedev, S., Adam, J., et al.Seismic evidence for stratification in composition and anisotropic fabric within the thick lithosphere of Kalahari craton.Geochemistry, Geophysics, Geosystems: G3, Vol. 14, 12, pp. 5393-5412.Africa, South AfricaGeophysics - seismics
DS200612-0603
2006
Yuan, Z.Hou, Z., Tian, S., Yuan, Z., Xie, Y., Yin, S., Yi, L., Fei, H., Yang, Z.The Himalayan collision zone carbonatites in western Sichuan, SW China: petrogenesis, mantle source and tectonic implication.Earth and Planetary Science Letters, in pressAsia, ChinaCarbonatite
DS200912-0313
2009
Yuan, Z.Hou, Z., Tian, S., Xie, Y., Yang, Z., Yuan, Z., Yin, S., Yi, L., Fei, H., Zou, T., Bai, G., Li, X.The Himalayan Mianning Dechang REE belt associated with carbonatite alkaline complexes eastern Indo Asian collision zone, SW China.Ore Geology Reviews, Vol. 36, 1-3, pp. 65-89.ChinaCarbonatite
DS1992-1728
1992
Yuan, Z.X.Yuan, Z.X., et al.Geological features and genesis of the Bayan Obo rare earth elements (REE) ore deposit, InnerMongolia, ChinaApplied Geochemistry, Vol.7, No. 5, September pp. 429-442ChinaRare earths carbonatite, Deposit -Bayan Obo
DS1992-1716
1992
Yuan CaoYang Ruiying, Yuan CaoA preliminary study on the trace element geochemistry of ultramafic inclusions in the eastern part of Lianoning-Jilin ChinaInternational Symposium Cenozoic Volcanic Rocks Deep seated xenoliths China and its, Abstracts pp. 103-104ChinaGeochemistry, Ultramafic
DS1992-1705
1992
Yuan ChaoXu Weniang, Chi Xiaoguo, Yuan Chao, Yiang RuiyangThe upper mantle and lower crust in the central North Chin a PlatformInternational Symposium Cenozoic Volcanic Rocks Deep seated xenoliths China and its, Abstracts pp. 98-101ChinaMantle, Xenoliths
DS1990-0648
1990
Yuan QilinHan Zongzhu, Yuan Qilin, Sheng Xingtu, NI BangfaThe garnet in eclogite and garnet peridotite in Labieshan Mountain areaInternational Mineralogical Association Meeting Held June, 1990 Beijing, Vol. 2, extended abstract p. 854-855ChinaGarnet, Eclogites
DS1990-1616
1990
Yuan ZhongxinYuan Zhongxin, Bai GeGeological features of Baiyan -Obo ore deposit and its genetic analyisInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 975ChinaCarbonatite, Baiyan -Obo
DS1992-1727
1992
Yuan ZhongxinYuan ZhongxinRare and rare earth mineral deposits related to alkaline igneous rocks and carbonatites in ChinaProceedings of the 29th International Geological Congress. Held Japan August 1992, Vol. 2, abstract p. 570ChinaCarbonatite
DS201511-1840
2015
Yuasa, M.Harada, Y., Hishinuma, R., Terashima, C., Uetsuka, H., Nakata, K., Kondo, T., Yuasa, M., Fujishima, A.Rapid growth of diamond and its morphology by in-liquid plasma CVD.Diamond and Related Materials, in press available, 16p.TechnologySynthetics

Abstract: Diamond synthesis and its morphology by in-liquid plasma chemical vapor deposition (CVD) method are investigated in this study. Diamond films were grown on Si substrates from mixed alcohol solution. Very high growth rate of 170 ?m/h was achieved by this method. Microcrystalline and nanocrystalline diamond films were formed in different conditions. In the case of microcrystalline film, the shapes of diamond grains depend on the location in the film. All morphological differences in this study can be explained by the same mechanism of conventional gas phase CVD method. It means diamond morphology by in-liquid plasma CVD method can be controlled by process parameters as well as gas phase CVD method.
DS200512-1263
2005
Yuchuan, C.Zhenyu, C., Yuchuan, C., Denghong, W., Xu, J., Zhou, J.Rutiles in eclogite from the Sulu UHPM terrane: a preliminary study.Mineral deposit Research: Meeting the Global Challenge. 8th Biennial SGA Beijing, Aug. 18-22, 2005. Springer, Chapter 7-3, pp. 731-734.ChinaUHP
DS200612-1612
2006
Yuchuan, C.Zhenyu, C., Yuchuan, C., Denghong, W., Jue, X., Jianxiong, Z.Rutiles in eclogites from the Sulu UHPM terrane: a preliminary study.Maor & Bierlein eds. Understanding ore systems through precise geochronology, isotope tracing, microgeochem., Chapter 7-36, pp.861-864.ChinaUHP
DS201705-0825
2017
Yudalevich, Z.A.Fershtater, G.B., Yudalevich, Z.A.Mantle metasomatism and magma formation in continental lithosphere: dat a on xenoliths in alkali basalts from the Makhtesh Ramon, Negrev Desert, Israel.Petrology, Vol. 25, 2, pp. 181-205.Asia, IsraelBasanites
DS1986-0120
1986
YudeCai 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
DS200712-1210
2007
Yudelman, D.Yudelman, D.Canadian diamond projects approach production decision....Advanced projects .. will the grades and values make them into mines?Diamonds in Canada Magazine, Northern Miner, June p. 20-22, 29-30.CanadaExploration projects
DS200812-1301
2007
Yudelman, D.Yudelman, D.Canadian diamond production: peaking or just taking off? Province by province brief overviewDiamonds in Canada Magazine, Northern Miner, November pp. 16-22.CanadaNews item - brief overview
DS200812-1302
2008
Yudelman, D.Yudelman, D.De Beers opening Canadian mines and minds.Northern Miner Diamonds in Canada, November pp. 6-11, 15-16.Canada, Northwest Territories, OntarioOverview - Snap Lake, Victor, De Beers
DS201412-0020
2014
Yudin, D.Ashchepkov, I., Remirs, L., Ntaflos, T., Vladykin, N., Logvinova, A., Travin, A., Yudin, D., Karpenko, K., Makovchuk, I., Palessky, S., Salikhov, R.Evolution of mantle column of pipe Sytykanskaya, Yakutia kimberlite.Goldschmidt Conference 2014, 1p. AbstractRussia, YakutiaDeposit - Sytykanskaya
DS201112-1095
2011
Yudin, D.S.Vrublevskii, V.V., Reverdatto, V.V., Izokh, A.E., Gertner, I.F., Yudin, D.S., Tishin, P.A.Neoproterozoic carbonatite magmatism of the Yenesei Ridge, central Siberia: 40AR39Ar geochronology of the Penchenga rock complex.Doklady Earth Sciences, Vol. 437, 2, pp. 443-448.Russia, SiberiaCarbonatite
DS201212-0559
2012
Yudin, D.S.Pokhilenko, L.N., Alifirova, T.A., Yudin, D.S.40Ar/39Ar dating of phlogopite of mantle xenoliths from kimberlite pipes of Yakutia: evidence for deep ancient metasomatism of the Siberian platform.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractRussia, YakutiaGeochronology
DS201212-0560
2012
Yudin, D.S.Pokhilenko, L.N., Aliflrova, T.A., Yudin, D.S.40Ar/39Ar dating of phlogopite of mantle xenoliths from kimberlite pipes of Yakutia: evidence for deep ancient metasomatism of the Siberian platform.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractRussia, SiberiaGeochronology
DS201312-0509
2013
Yudin, D.S.Kostrovitsky, S.I., Soloveva, L.V., Yakovlev, D.A., Suvorova, L.F., Sandimirova, G.P., Travin, A.V., Yudin, D.S.Kimberlites and megacrystic suite: isotope geochemical studies.Petrology, Vol. 21, 2, pp. 127-144.Russia, YakutiaDeposit - Udachnaya
DS201412-0023
2014
Yudin, D.S.Ashchepkov, I.V., Vladykin, N.V., Ntaflos, T., Yudin, D.S., Karpenko, M.A., Palesskiy, V.S., Khmelnikova, O.S.Deep seated xenoliths and xencrysts from Stykanskaya pipe: evidence for the evolution of the mantle beneath Alakit, Yakutia.Deep Seated Magmatism, its sources and plumes, Ed. Vladykin, N.V., pp. 203-229.RussiaDeposit - Stykanskaya
DS201412-1013
2014
Yudin, D.S.Yudin, D.S., Tomilenko, A.A., Travin, A.V., Agashev, A.M., Pokhilenko, N.P., Orihashi, yu.The age of the Udachnaya-East kimberlite: U/Pb and 40 Ar/39Ar data.Doklady Earth Sciences, Vol. 455, 1, pp. 288-290.RussiaDeposit - Udachnaya
DS201510-1758
2015
Yudin, D.S.Ashchepkov, I.V., Logvinova, A.M., Reimers, L.F., Ntaflos, T., Spetisus, Z.V., Vladykin, N.V., Downes, H., Yudin, D.S., Travin, A.V., Makovchuk, I.V., Palesskiy, V.S., KhmelNikova, O.S.The Sytykanskaya kimberlite pipe: evidence from deep seated xenoliths and xenocrysts for the evolution of the mantle beneath Alakit, Yakutia, Russia.Geoscience Frontiers, Vol. 6, 5, pp. 687-714.Russia, YakutiaDeposit - Sytykanskaya

Abstract: Mantle xenoliths (>150) and concentrates from late autolithic breccia and porphyritic kimberlite from the Sytykanskaya pipe of the Alakit field (Yakutia) were analyzed by EPMA and LAM ICP methods. In P-T-X-f(O2) diagrams minerals from xenoliths show widest variations, the trends P-Fe#-CaO, f(O2) for minerals from porphyric kimberlites are more stepped than for xenocrysts from breccia. Ilmenite PTX points mark moving for protokimberlites from the lithosphere base (7.5 GPa) to pyroxenite lens (5-3.5 GPa) accompanied by Cr increase by AFC and creation of two trends P-Fe#Ol ?10-12% and 13-15%. The Opx-Gar-based mantle geotherm in Alakit field is close to 35 mW/m2 at 65 GPa and 600 °C near Moho was determined. The oxidation state for the megacrystalline ilmenites is lower for the metasomatic associations due to reduction of protokimberlites on peridotites than for uncontaminated varieties at the lithosphere base. Highly inclined linear REE patterns with deep HFSE troughs for the parental melts of clinopyroxene and garnet xenocrysts from breccia were influenced by differentiated protokimberlite. Melts for metasomatic xenoliths reveal less inclined slopes without deep troughs in spider diagrams. Garnets reveal S-shaped REE patterns. The clinopyroxenes from graphite bearing Cr-websterites show inclined and inflected in Gd spectrums with LREE variations due to AFC differentiation. Melts for garnets display less inclined patterns and Ba-Sr troughs but enrichment in Nb-Ta-U. The 40Ar/39Ar ages for micas from the Alakit mantle xenoliths for disseminated phlogopites reveal Proterozoic (1154 Ma) age of metasomatism in early Rodinia mantle. Veined glimmerites with richterite - like amphiboles mark ?1015 Ma plume event in Rodinia mantle. The ?600-550 Ma stage manifests final Rodinia break-up. The last 385 Ma metasomatism is protokimberlite-related.
DS201510-1759
2014
Yudin, D.S.Ashchepkov, I.V., Vladykin, N.V., Ntaflos, T., Logvinova, A.M., Yudin, D.S., Karpenko, M.A., Paleeskiy, V.S., Alymova, N.V., Khmelnikova, O.S.Deep seated xenoliths and xencrysts from Sytykanskaya pipe: evidence for the evolution of the mantle beneath Alakit, Yakutia.Deep-seated magmatism, its sources and plumes, Proceedings of XIII International Workshop held 2014., Vol. 2014, pp. 203-232.Russia, YakutiaDeposit - Sytykanskaya

Abstract: The concentrate from two phases of the kimberlite (breccia and porphyritic kimberlite) and about 130 xenoliths from the Sytykanskaya pipe of the Alakit field (Yakutia) were studied by EPMA and LAM ICP methods. Reconstructions of the PTXfO2 mantle sections were made separately for the two phases. The porphyritic kimberlites and breccia show differences in the minerals although the layering and pressure interval remains the same. For the porphyritic kimberlite the trends P- Fe# - CaO in garnet, fO2 are sub-vertical while the xenocrysts from the breccia show stepped and curved trends possibly due to interaction with fluids. Minerals within xenoliths show the widest variation in all pressure intervals. PT points for the ilmenites which trace the magmatic system show splitting of the magmatic source into two levels at the pyroxenite lens (4GPa) accompanied by peridotite contamination and an increase in Cr in ilmenites. Two groups of metasomatites with Fe#Ol ~ 10-12% and 13-15% were created by the melts derived from protokimberlites and trace the mantle columns from the lithosphere base (Ilm - Gar - Cr diopside) to Moho becoming essentially pyroxenitic (Cr-diopside with Phl). The first Opx-Gar-based mantle geotherm from the Alakit field has been constructed from15 associations and is close to 35 mw/m2 in the lower part of mantle section but deviates to high temperatures in the upper part of the mantle section. The oxidation state for the protokimberlite melts determined from ilmenites is higher than for the other pipes in the Yakutian kimberlite province which probably accounts for the decrease in the diamond grade of this pipe. The geochemistry of the minerals (garnets and clinopyroxenes) from breccias, metasomatic peridotite xenoliths and pyroxenites systematically differ. Xenocrysts from the breccia were produced by the most differentiated melts and enriched protokimberlite or carbonatite; they show highly inclined nearly linear REE patterns and deep troughs of HFSE. Minerals of the metasomatic xenoliths are less inclined with lower La/Cen ratios and without troughs in spider diagrams. The garnets often show S-shaped patterns. Garnets from the Cr websterites show round REE patterns and deep troughs in Ba-Sr but enrichment in Nb-Ta-U. The clinopyroxenes reveal the inclined and inflected on Gd spectrums with variations in LREE due to AFC differentiation. The 40Ar-39Ar ages for micas from the Alakit field reveal three intervals for the metasomatism. The first (1154 Ma) relates to dispersed phlogopites found throughout the mantle column, and probably corresponds to the continental arc stage in the early stage of Rodinia. Veined highly alkaline and Ti-rich veins with richterite ~1015 Ma corresponds to the plume event within the Rodinia mantle. The ~600-550 Ma stage marks the final Rodinia break-up. The last one near 385 Ma is protokimberlite related.
DS201608-1452
2016
Yudin, D.S.Yudin, D.S., Tomilanko, A.A., Alifirova, T.A., Travin, A.V., Murzintsev, N.G., Pokhilenko, N.P.Results of 40 Ar/39 Ar dating of phlogopites from kelphyphitic rims around garnet grains ( Udachnaya- Vostochnaya pipe).Doklady Earth Sciences, Vol. 469, 1, pp. 728-731.RussiaDeposit - Udachnaya - Vostochnaya
DS201612-2315
2016
Yudin, D.S.Larionova, Yu.O., Sazonova, L.V., Lebedeva, N.M., Nosova, A.A., Tretyachenko, V.V., Travin, A.V., Kargin, A.V., Yudin, D.S.Kimberlite age in the Arkhangelsk province, Russia: isotopic geochronologic Rb-Sr and 40Ar/39Ar and mineralogical dat a on phlogopite.Petrology, Vol. 24, 6, pp. 562-593.Russia, Archangel, Kola PeninsulaDeposit - Ermakovskaya-7, Grib, Karpinski

Abstract: The paper reports detailed data on phlogopite from kimberlite of three facies types in the Arkhangelsk Diamondiferous Province (ADP): (i) massive magmatic kimberlite (Ermakovskaya-7 Pipe), (ii) transitional type between massive volcaniclastic and magmatic kimberlite (Grib Pipe), and (iii) volcanic kimberlite (Karpinskii-1 and Karpinskii-2 pipes). Kimberlite from the Ermakovskaya-7 Pipe contains only groundmass phlogopite. Kimberlite from the Grib Pipe contains a number of phlogopite populations: megacrysts, macrocrysts, matrix phlogopite, and this mineral in xenoliths. Phlogopite macrocrysts and matrix phlogopite define a single compositional trend reflecting the evolution of the kimberlite melt. The composition points of phlogopite from the xenoliths lie on a single crystallization trend, i.e., the mineral also crystallized from kimberlite melt, which likely actively metasomatized the host rocks from which the xenoliths were captured. Phlogopite from volcaniclastic kimberlite from the Karpinskii-1 and Karpinskii-2 pipes does not show either any clearly distinct petrographic setting or compositional differentiation. The kimberlite was dated by the Rb-Sr technique on phlogopite and additionally by the 40Ar/39Ar method. Because it is highly probable that phlogopite from all pipes crystallized from kimberlite melt, the crystallization age of the kimberlite can be defined as 376 ± 3 Ma for the Grib Pipe, 380 ± 2 Ma for the Karpinskii-1 pipe, 375 ± 2 Ma for the Karpinskii-2 Pipe, and 377 ± 0.4 Ma for the Ermakovskaya-7 Pipe. The age of the pipes coincides within the error and suggests that the melts of the pipes were emplaced almost simultaneously. Our geochronologic data on kimberlite emplacement in ADP lie within the range of 380 ± 2 to 375 ± Ma and coincide with most age values for Devonian alkaline-ultramafic complexes in the Kola Province: 379 ± 5 Ma; Arzamastsev and Wu, 2014). These data indicate that the kimberlite was formed during the early evolution of the Kola Province, when alkaline-ultramafic complexes (including those with carbonatite) were emplaced.
DS201704-0618
2017
Yudin, D.S.Aramastsev, A.A., Vesolovskiy, R.V., Travin, A.V., Yudin, D.S.Paleozoic tholeiitic magmatism of the Kola Peninsula: spatial distribution, age, and relation to alkaline magmatism.Petrology, Vol. 25, 1, pp. 42-65.Russia, Kola PeninsulaMagmatism - alkaline

Abstract: This paper focuses on the occurrences of tholeiitic magmatism in the northeastern Fennoscandian shield. It was found that numerous dolerite dikes of the Pechenga, Barents Sea, and Eastern Kola swarms were formed 380-390 Ma ago, i.e., directly before the main stage of the Paleozoic alkaline magmatism of the Kola province. The isotope geochemical characteristics of the dolerites suggest that their primary melts were derived from the mantle under the conditions of the spinel lherzolite facies. The depleted mantle material from which the tholeiites were derived shows no evidence for metasomatism and enrichment in high fieldstrength and rare earth elements, whereas melanephelinite melts postdating the tholeiites were generated in an enriched source. It was shown that the relatively short stage of mantle metasomatism directly after the emplacement of tholeiitic magmas was accompanied by significant mantle fertilization. In contrast to other large igneous provinces, where pulsed intrusion of large volumes of tholeiitic magmas coinciding or alternating with phases of alkaline magmatism was documented, the Kola province is characterized by systematic evolution of the Paleozoic plume-lithosphere process with monotonous deepening of the level of magma generation, development of mantle metasomatism and accompanying fertilization of mantle materials, and systematic changes in the composition of melts reaching the surface.
DS201707-1344
2016
Yudin, D.S.Larionova, Y.O., Sazonova, L.V., Lebedeva, N.M., Nosova, A., Tretyachenko, V.V., Travin, A.V., Kargin, A.V., Yudin, D.S.Kimberlite age in the Arkhangelsk province, Russia: isotopic geochronologic Rb-Sr and 40Ar/39Ar and mineralogical dat a on phlogopite.Petrology, Vol. 24, 6, pp. 562-593.Russiageochronology

Abstract: The paper reports detailed data on phlogopite from kimberlite of three facies types in the Arkhangelsk Diamondiferous Province (ADP): (i) massive magmatic kimberlite (Ermakovskaya-7 Pipe), (ii) transitional type between massive volcaniclastic and magmatic kimberlite (Grib Pipe), and (iii) volcanic kimberlite (Karpinskii-1 and Karpinskii-2 pipes). Kimberlite from the Ermakovskaya-7 Pipe contains only groundmass phlogopite. Kimberlite from the Grib Pipe contains a number of phlogopite populations: megacrysts, macrocrysts, matrix phlogopite, and this mineral in xenoliths. Phlogopite macrocrysts and matrix phlogopite define a single compositional trend reflecting the evolution of the kimberlite melt. The composition points of phlogopite from the xenoliths lie on a single crystallization trend, i.e., the mineral also crystallized from kimberlite melt, which likely actively metasomatized the host rocks from which the xenoliths were captured. Phlogopite from volcaniclastic kimberlite from the Karpinskii-1 and Karpinskii-2 pipes does not show either any clearly distinct petrographic setting or compositional differentiation. The kimberlite was dated by the Rb–Sr technique on phlogopite and additionally by the 40Ar/39Ar method. Because it is highly probable that phlogopite from all pipes crystallized from kimberlite melt, the crystallization age of the kimberlite can be defined as 376 ± 3 Ma for the Grib Pipe, 380 ± 2 Ma for the Karpinskii-1 pipe, 375 ± 2 Ma for the Karpinskii-2 Pipe, and 377 ± 0.4 Ma for the Ermakovskaya-7 Pipe. The age of the pipes coincides within the error and suggests that the melts of the pipes were emplaced almost simultaneously. Our geochronologic data on kimberlite emplacement in ADP lie within the range of 380 ± 2 to 375 ± Ma and coincide with most age values for Devonian alkaline–ultramafic complexes in the Kola Province: 379 ± 5 Ma; Arzamastsev and Wu, 2014). These data indicate that the kimberlite was formed during the early evolution of the Kola Province, when alkaline–ultramafic complexes (including those with carbonatite) were emplaced.
DS201712-2678
2017
Yudin, D.S.Chebotarev, D.A., Doroshkevich, A.G., Sharygin, V.V., Yudin, D.S., Ponomarchuk, A.V., Sergeev, S.A.Geochronology of the Chuktukon carbonatite massif, Chadobets uplift ( Krasnoyarsk Territory).Russian Geology and Geophysics, Vol. 58, pp. 1222-1231.Russiacarbonatite

Abstract: We present results of U-Pb (SHRIMP II) and Ar-Ar geochronological study of the rocks of the Chuktukon massif, which is part of the Chadobets alkaline-carbonatite complex, and of the weathering crust developed after them. Perovskite from picrites and monazite from the weathering crust were dated by the U-Pb (SHRIMP II) method, and rippite from carbonatites, by the Ar-Ar method. Rippite has first been used as a geochronometer. The estimated ages (252 ± 12 and 231 ± 2.7 Ma) testify to two magmatism pulses close in time (within the estimation error) to the stages of alkaline magmatism in the Siberian Platform (250-245 and 238-234 Ma). These pulses characterize, most likely, the processes accompanying and completing the activity of the mantle superplume that formed the Siberian Igneous Province at 250-248 Ma. The monazite-estimated age (102.6 ± 2.9 Ma) reflects the time of formation of the ore-bearing weathering crust on the massif rocks.
DS201908-1820
2019
Yudin, D.S.Veselovskiy, R.V., Thomson, S.N., Arzamastsev, A.A., Botsyun, S.B., Travin, A.V., Yudin, D.S., Samsonov, A.V., Stepanova, A.V.Thermochronology and exhumation history of the northeastern Fennoscandian Shield since 1.9 Ga: evidence from 40AR/39Ar and apatite fission track data from the Kola Peninsula.Tectonics, doi.org/10.1029 /2018TC005250Europe, Kola Peninsulageochronology

Abstract: Results from thermochronological studies have multiple applications to various problems in tectonics and landform evolution However, up to now a lack of thermochronological data from the northeastern Fennoscandian Shield has complicated the interpretation of tectonothermal evolution of the region Here, we use both new and previously published multimineral 40Ar/39Ar data (amphibole, mica, and feldspar) on the various Precambrian magmatic and metamorphic complexes to reconstruct the thermal history of NE Fennoscandia within the Kola Peninsula area in the interval 1900–360 Ma Using the apatite fission track method as well as a numerical model of the heating?cooling process of northeastern Fennoscandia's upper crust, we have reconstructed its thermal evolution for the interval 360–0 Ma According to our model, since Lapland?Kola orogenesis (1930–1905 Ma) northeastern Fennoscandia experienced a quasi?monotonous cooling with the average rate of ~0 15 °C/Myr, which is equal to an exhumation rate of ~1–2 m/Myr New apatite fission track data and time?temperature modeling reveal a “hidden” endogenous thermal event in the NE Fennoscandia that took place between 360 and 300 Ma This we attribute to an elevated geothermal gradient due to Baltica's drift over the African large low shear?wave velocity province in the lowest mantle and/or thermal blanketing by insulating Devonian?Carboniferous sedimentary/volcanic cover Our model is further supported by evidence of Late Devonian?Carboniferous rifting in the East and South?Western Barents Basin, as well as various 360–300 Ma magmatic events within SW Fennoscandia and the Baltic countries
DS201909-2103
2019
Yudin, D.S.Veselovskiy, R.V., Thomson, S.N., Arzamastsev, A.A., Botsyun, S., Travin, A.V., Yudin, D.S., Samsonov, A.V., Stepanova, A.V.Thermochronology and exhumation history of the northeastern Fennoscandian shield since 1.9 Ga: evidence from 40Ar/39/Ar and apatite fission track data from the Kola Peninsula.Tectonics, Vol. 38, 7, pp. 2317-2337.Europe, Fennoscandia, Kola Peninsulageochronology

Abstract: Results from thermochronological studies have multiple applications to various problems in tectonics and landform evolution. However, up to now a lack of thermochronological data from the northeastern Fennoscandian Shield has complicated the interpretation of tectonothermal evolution of the region. Here, we use both new and previously published multimineral 40Ar/39Ar data (amphibole, mica, and feldspar) on the various Precambrian magmatic and metamorphic complexes to reconstruct the thermal history of NE Fennoscandia within the Kola Peninsula area in the interval 1900-360 Ma. Using the apatite fission track method as well as a numerical model of the heating?cooling process of northeastern Fennoscandia's upper crust, we have reconstructed its thermal evolution for the interval 360-0 Ma. According to our model, since Lapland?Kola orogenesis (1930-1905 Ma) northeastern Fennoscandia experienced a quasi?monotonous cooling with the average rate of ~0.15 °C/Myr, which is equal to an exhumation rate of ~1-2 m/Myr. New apatite fission track data and time?temperature modeling reveal a “hidden” endogenous thermal event in the NE Fennoscandia that took place between 360 and 300 Ma. This we attribute to an elevated geothermal gradient due to Baltica's drift over the African large low shear?wave velocity province in the lowest mantle and/or thermal blanketing by insulating Devonian?Carboniferous sedimentary/volcanic cover. Our model is further supported by evidence of Late Devonian?Carboniferous rifting in the East and South?Western Barents Basin, as well as various 360-300 Ma magmatic events within SW Fennoscandia and the Baltic countries.
DS201911-2508
2019
Yudin, D.S.Ashchepkov, I.V., Mevedev, N.S., Yudin, D.S., Ntaflos, T., Makovchuk, I.V., Ivanov, A.S., Kiseeva, E.Mantle columns beneath Kosomolskaya and Zarnitsa kimberlite pipes: xenolith study.Goldschmidt2019, 1p. AbstractRussiadeposit - Kosomolskaya, Zarnitsa

Abstract: Mantle xenolith from Komsomolskya and Zarnitsa pie were used for the reconstryctions of mantle columns beneath theses kimberlite pipes. Relatively fresh mantle xenolith from Zarnitsa and Komsomolskaya pipes we used for PTX reconstructions of mantle sections. In Zarnitsa dunites - harburgites with richterite, Phl-Ilm veins, sheared lherzolites, pyroxenites (with amphibole) and eclogites and deformed peridotites. Mg -rich Gar and Opx formed stepped P-Fe# trend, Fe- enriched Cpx with Ilm were created mostly by protkimberlites. Sub Ca garnets rarely show U spikes while Ti rich show Th, U, Ta, Nb, Zr and peaks Many minerals demonstrate Th enrichment due to carbonitites. In mantle of Komsomolskaya pipe Phl is wide spreadin periditites from lherzolites ti dunites and in eclogites. There are 6 intervals with sharp division at 5 GPa.Mg eclogites prevae in lower part while fe- enriched in middle part. The Fe# rise is detevcted in lower and upper parts of mantle section. The TRE spiderdiagrams of grnets shows U -pb subduction peaks But Cpx mainly show n Th- peak. The ages of eclogites ogive 500-600 Ma (one 1525 MA) which is much less than in Zarnitsa or Udachnaya having Proterozoic - Archean ages.
DS202005-0754
2020
Yudin, D.S.Nosova, A.A., Kargin, A.V., Sazonova, L.V., Dubinina, E.O., Chugaev, A.V., Lebedeva, N.M., Yudin, D.S., Larionova, Y.O., Abersteiner, A., Gareev, B.I., Batalin, G.A.Sr-Nd-Pb isotopic systematic and geochronology of ultramafic alkaline magmatism of the southwestern margin of the Siberian craton: metasomatism of the sub-continental lithospheric mantle related to subduction and plume events.Lithos, Vol. 364-365, 21p. PdfRussia, Siberiadeposit - Ilbokich, Chadobets

Abstract: To provide new insights into the origin and evolution of ultramafic lamprophyres (UMLs) and their mantle source, we examined two UML (aillikite and damtjernite) occurrences of different ages in the western portion of the Siberian Craton (Ilbokich and Chadobets). New age, mineral and rock geochemistry, along with Sr-Nd-Pb-C-O isotope data was obtained. Our new 206Pb/238U perovskite age (399 ± 4 Ma) confirms the previously published Early Devonian age of the Ilbokich aillikite. RbSr isochron and 40Ar/39Ar dating yielded a Middle Triassic age (243 ± 3 Ma and 241 ± 1 Ma, respectively) for the Chadobets aillikites, indicating post-Trap emplacement of these rocks. Both UMLs are characterized by incompatible elements, including light rare earth element (LREE) enrichments (La is up to ×200 chondrite concentration), and strong fractionation of REEs ((La/Yb)n: 33-84). Despite the close geochemical affinity of both UMLs, the Nd isotopic compositions of aillikites, as well as the Pb isotopic composition of Chadobets and Ilbokich UMLs, do not overlap and are distinctly different from each other. The initial Sr and Nd isotopic compositions of the Ilbokich UMLs fall in within a narrow 87Sr/86Sr0 range (0.7032-0.7042) and ?Nd(T) (4.03-3.97). Chadobets UMLs have a similar Sr isotopic signature (87Sr/86Sr0: 0.7031-0.7043) and a more depleted Nd isotopic signature (?Nd(T) 4.09-5.08). The initial Pb isotope compositions of the Chadobets UMLs are moderately radiogenic, ranging between 206Pb/204Pb = 18.4-19.0, 208Pb/204Pb = 38.3-38.8, and are characterized by a narrow 207Pb/204Pb ratio between 15.5 and 15.6. The Ilbokich Pb isotope compositions are less variable and range between 206Pb/204Pb = 18.0-18.4, 208Pb/204Pb = 37.8-38.4 and 207Pb/204Pb ratios between 15.5 and 15.6. The oxygen isotopic composition of carbonate from both UMLs is characterized by highly variable ?18O values from +12.1 and up to +20.5‰ (SMOW). The isotopic composition of ?13C values range from ?1.3‰ to ?7.1. Based on the minor impact of crustal contamination in both aillikites, it is inferred that their radiogenic isotope composition reflects a mantle source signature. The mantle source of the Chadobets aillikites is likely to include carbonatitic magma as a metasomatic agent. In contrast, phlogopite-rich metasomes within the lithospheric mantle could have contributed more significantly to the Ilbokich aillikites. These metasomes could be formed during the Caledonian orogeny, which did not only affect the southwestern boundary of the Siberian Craton, but also expanded to the craton interior. This study provides additional support for the evolution of the south-western portion of the Siberian SCLM, ranging from mantle containing phlogopite enrichment domains during the Early Devonian to hydrous-phase reduced mantle in the Triassic due to the thermal impact of the Siberian Traps.
DS202006-0943
2020
Yudin, D.S.Novosa, A.A., Kargin, A.V., Sazonova, L.V., Dubinina, E.O., Chugaev, A.V., Lebedeva, N.M., Yudin, D.S., Larionova, Y.O., Abersteiner, A., Gareev, B.I., Batalin, G.A.Sr-N-Pb isotopic systematic and geochronology of ultramafic alkaline magmatism of the southwestern margin of the Siberian craton: metasomatism of the sub-continental lithospheric mantle related to subduction and plume events.Lithos, Vol. 364-365, 21p. PdfRussiaailikite, damjernite

Abstract: To provide new insights into the origin and evolution of ultramafic lamprophyres (UMLs) and their mantle source, we examined two UML (aillikite and damtjernite) occurrences of different ages in the western portion of the Siberian Craton (Ilbokich and Chadobets). New age, mineral and rock geochemistry, along with Sr-Nd-Pb-C-O isotope data was obtained. Our new 206Pb/238U perovskite age (399 ± 4 Ma) confirms the previously published Early Devonian age of the Ilbokich aillikite. RbSr isochron and 40Ar/39Ar dating yielded a Middle Triassic age (243 ± 3 Ma and 241 ± 1 Ma, respectively) for the Chadobets aillikites, indicating post-Trap emplacement of these rocks. Both UMLs are characterized by incompatible elements, including light rare earth element (LREE) enrichments (La is up to ×200 chondrite concentration), and strong fractionation of REEs ((La/Yb)n: 33-84). Despite the close geochemical affinity of both UMLs, the Nd isotopic compositions of aillikites, as well as the Pb isotopic composition of Chadobets and Ilbokich UMLs, do not overlap and are distinctly different from each other. The initial Sr and Nd isotopic compositions of the Ilbokich UMLs fall in within a narrow 87Sr/86Sr0 range (0.7032-0.7042) and ?Nd(T) (4.03-3.97). Chadobets UMLs have a similar Sr isotopic signature (87Sr/86Sr0: 0.7031-0.7043) and a more depleted Nd isotopic signature (?Nd(T) 4.09-5.08). The initial Pb isotope compositions of the Chadobets UMLs are moderately radiogenic, ranging between 206Pb/204Pb = 18.4-19.0, 208Pb/204Pb = 38.3-38.8, and are characterized by a narrow 207Pb/204Pb ratio between 15.5 and 15.6. The Ilbokich Pb isotope compositions are less variable and range between 206Pb/204Pb = 18.0-18.4, 208Pb/204Pb = 37.8-38.4 and 207Pb/204Pb ratios between 15.5 and 15.6. The oxygen isotopic composition of carbonate from both UMLs is characterized by highly variable ?18O values from +12.1 and up to +20.5‰ (SMOW). The isotopic composition of ?13C values range from ?1.3‰ to ?7.1. Based on the minor impact of crustal contamination in both aillikites, it is inferred that their radiogenic isotope composition reflects a mantle source signature. The mantle source of the Chadobets aillikites is likely to include carbonatitic magma as a metasomatic agent. In contrast, phlogopite-rich metasomes within the lithospheric mantle could have contributed more significantly to the Ilbokich aillikites. These metasomes could be formed during the Caledonian orogeny, which did not only affect the southwestern boundary of the Siberian Craton, but also expanded to the craton interior. This study provides additional support for the evolution of the south-western portion of the Siberian SCLM, ranging from mantle containing phlogopite enrichment domains during the Early Devonian to hydrous-phase reduced mantle in the Triassic due to the thermal impact of the Siberian Traps.
DS202003-0352
2020
Yudovskaya, M.Moore, A.,Yudovskaya, M., Prover, A., Blenkinsop, T.Evidence for olivine deformation in kimberlites and other mantle derived magmas during crustal emplacement. LemphaneContributions to Mineralogy and Petrology, Vol. 175, 9p. PdfAfrica, Lesothoolivine

Abstract: This paper highlights published and new field and petrographic observations for late-stage (crustal level) deformation associated with the emplacement of kimberlites and other mantle-derived magmas. Thus, radial and tangential joint sets in the competent 183 Ma Karoo basalt wall rocks to the 5 ha. Lemphane kimberlite blow in northern Lesotho have been ascribed to stresses linked to eruption of the kimberlite magma. Further examples of emplacement-related stresses in kimberlites are brittle fractures and close-spaced parallel shears which disrupt olivine macrocrysts. In each of these examples, there is no evidence of post-kimberlite regional tectonism which might explain these features, indicating that they reflect auto-deformation in the kimberlite during or immediately post-emplacement. On a microscopic scale, these inferred late-stage stresses are reflected by fractures and domains of undulose extinction which traverse core and margins of some euhedral and anhedral olivines in kimberlites and olivine melilitites. Undulose extinction and kink bands have also been documented in olivines in cumulates from layered igneous intrusions. Our observations thus indicate that these deformation features can form at shallow levels (crustal pressures), which is supported by experimental evidence. Undulose extinction and kink bands have previously been presented as conclusive evidence for a mantle provenance of the olivines—i.e. that they are xenocrysts. The observation that these deformation textures can form in both mantle and crustal environments implies that they do not provide reliable constraints on the provenance of the olivines. An understanding of the processes responsible for crustal deformation of kimberlites could potentially refine our understanding of kimberlite emplacement processes.
DS2000-0498
2000
Yue, D.A.Kido, M., Yue, D.A.The role of a low viscosity zone under a 660 km discontinuity in regional mantle layering.Earth and Planetary Science Letters, Vol.181, No.4, Sept.30, pp.573-83.MantleGeophysics - seismics, Discontinuity, convection
DS1983-0644
1983
Yue, M.Yue, M.How to Buy Gems. Five Part SeriesLapidary Journal, Vol. 37, No. 1, APRIL PP. 80-82.; No. 2, MAY PP. 338-342.; NOGlobalInvestment, Diamonds
DS202003-0362
2020
Yue, W.Sha, X., Yue, W., Zhang, H., Qin, W., She, D., Wang, C.Thermal stability of polycrystalline diamond compact sintered with boron coated diamond particles.Diamond & Related Materials, in press available, 34p. PdfGlobalboron

Abstract: The polycrystalline diamond compact (PDC), which consists of a polycrystalline diamond layer on a tungsten carbide (WC)/cobalt (Co) substrate, is extensively utilized as drilling bits. However, the poor thermal stability due to the graphitization and oxygen susceptibility of diamond severely limits the application of PDCs to high-temperature drilling work. In this study, a new PDC with improved thermal stability is successfully synthesized with boron (B)-coated diamond particles, which forms a uniform boron carbide (B4C) barrier. The as-received B4C phase acts as a protective barrier, which enhances the initial graphitization and oxidizing temperatures to 800 °C and 780 °C, respectively, which are ~100 °C and ~30 °C higher than those (700 °C and 750 °C) of the PDC sintered with uncoated diamond particles. The B4C barrier protects diamond grains from direct contact with the Co phase, prohibiting the cobalt-catalytic graphitization. In addition, the oxidation of the B4C barrier occurs prior to that of the diamond grains, which inhibits the PDC from oxidation.
DS2001-1287
2001
Yue, Y.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
DS1990-0763
1990
YueginJin, Yuegin, Taylor, L.A.Mantle and crustal xenoliths from a South Pacifichotspot: a fun visit toTaihiti Society IslandsGeological Society of America (GSA) Abstract Volume, Held Tuscaloosa, Alabama, April, Vol. 22, No. 4, p. 20. abstract onlyGlobalXenoliths, Hotspot
DS1990-1357
1990
Yuemin, G.Shuying, Q., Chujun, D., Yuemin, G.Study of prospecting mineralogy of spinel group in kimberlites in ChinaGems and Gemology, 15th, General Meeting, International Mineralogical, Vol. 26, Winter p. 310. AbstractChinaProspecting -spinel group, Diamond relationship
DS1996-0593
1996
Yuen, D.Hansen, U., Yuen, D.Potential role played by viscous heating in thermal chemical convection In the outer core.Geochimica Et Cosmochimica Acta, Vol. 60, No. 7, pp. 1113-23.MantleDensity - core, Model
DS200512-0849
2005
Yuen, D.Petford, N., Yuen, D., Rushmer, T.,Brodholt, J., Stackhouse, S.Shear induced material transfer across the core mantle boundary aided by the post perovskite phase transition.Earth Planets and Space, Vol. 57, 5, pp. 459-464.MantleMineralogy
DS200512-1098
2004
Yuen, D.Trampert, J.,Deschamps, F., Resovsky, J., Yuen, D.Probabilistic tomography maps chemical heterogeneities throughout the lower mantle.Science, Vol. 306, 5697, Oct 29, pp. 853-6.MantleTomography, geochemistry
DS200612-0586
2006
Yuen, D.Hirose, H., Karato, S., Comier, V., Brodholt, J., Yuen, D.Unsolved problems in the lowermost mantle.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 253. abstract only.MantleGeochemistry
DS1987-0273
1987
Yuen, D.A.Hansen, U., Yuen, D.A.Evolutionary structures in double diffusive convection in magma chambersGeophysical Research. Letters, Vol. 14, No. 11, November pp. 1099-1102GlobalBlank
DS1989-1149
1989
Yuen, D.A.Oldenburg, C.M., Spera, F.J., Yuen, D.A., Sewell, G.Dynamic mixing in magma bodies: theory, simulations and implicationsJournal of Geophysical Research, Vol. 94, No. B7, July 10, pp. 9215-9236GlobalMagma, Genesis
DS1990-0717
1990
Yuen, D.A.Honda, S., Yuen, D.A.Mantle convection with moving heat-source anomalies:geophysical and geochemical implicationsEarth and Planetary Science Letters, Vol. 96, pp. 349-366GlobalMantle, Heat flow -geochemistry/geophysics
DS1991-1001
1991
Yuen, D.A.Liu, M., Yuen, D.A., Zhao, W., Honda, S.Development of diapiric structures in the Upper mantle due to phasetransitionsScience, Vol. 252, June 24, pp. 1836-1839GlobalHot spot, Mantle
DS1992-1089
1992
Yuen, D.A.Morin, P.J., Yuen, D.A., Tanimoto, T., Yu-Shen ZhangVisualizing interactively the three dimensional structure of the earth'smantleEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 197MantleGeophysics, Structure
DS1993-0696
1993
Yuen, D.A.Honda, S., Yuen, D.A., Balachandar, S., Reuteler, D.Three-dimensional instabilities of mantle convection with multiple phasetransitionsScience, Vol. 259, February 26, pp. 1308-1311MantlePlumes, Tectonics
DS1994-1128
1994
Yuen, D.A.Matyska, C., Moser, J., Yuen, D.A.The potential influence of radiative heat transfer on the formation of megaplumes in the lower mantle.Earth and Planetary Science Letters, Vol. 125, pp. 255-266.MantlePlumes, Heat transfer
DS1994-1390
1994
Yuen, D.A.Podlachikov, Yu.Yu., Poliakov, A.N.B., Yuen, D.A.The effect of lithospheric phase transitions on subsidence of extending continental lithospheres.Earth and Planet. Science Letters, Vol. 124, No. 1-4, June pp. 95-104.MantleSubduction
DS1994-1971
1994
Yuen, D.A.Yuen, D.A., Cadek, O.P., Boehler, R., et al.Large cold anomalies in the deep mantle and mantle instability in theCretaceous.Terra Nova, Vol. 6, pp. 238-245.MantleGeophysics -seismics, Tomography
DS1995-0250
1995
Yuen, D.A.Cadek, O., Kyavlova, H., Yuen, D.A.Geodynamical implications from the correlation of surface geology and seismic tomographic structure.Earth and Planetary Science Letters, Vol. 136, pp. 615-627.MantleTomography, Geophysics -seismics
DS1995-1566
1995
Yuen, D.A.Reuteler, D.M., Balachander, S., Yuen, D.A.The generation of localized toroidal velocity patches from plume dynamics:implications spinning microplatesEos, Vol. 76, No. 46, Nov. 7. p.F633-4. Abstract.MantlePlumes, Geodynamics, Tectonics
DS1995-1825
1995
Yuen, D.A.Steinbach, V., Yuen, D.A.The effects of temperature dependent viscosity on mantle convection with the two major phase transitions.Physics of the Earth Plan. Interiors, Vol. 90, No. 1-2, July 1, pp. 13-36.MantleConvection
DS1995-2138
1995
Yuen, D.A.Zhang, S., Yuen, D.A.Formation of large scale linear upwelling plumes in mantle convection model with phase boundary depth 660km.Eos, Vol. 76, No. 46, Nov. 7. p.F634. Abstract.MantleConvection
DS1995-2139
1995
Yuen, D.A.Zhang, S., Yuen, D.A.The influences of lower mantle viscosity stratification on 3D spherical shell mantle convection.Earth and Planetary Science Letters, Vol. 132, pp. 157-166.MantleGeophysics -seismics, Lithosphere
DS1996-0319
1996
Yuen, D.A.Dabler, R., Yuen, D.A.The metastable olivine wedge in fast subducting slabs: constraints from thermo-kinetic coupling.Earth and Planetary Science Letters, Vol. 137, No. 1/4, Jan. 1, pp. 109-118.MantleGeodynamics, Subduction, plumes
DS1997-0651
1997
Yuen, D.A.Larsen, T.B., Yuen, D.A.Ultrafast upwelling bursting through the upper mantleEarth and Planetary Letters, Vol. 146, No. 3/4. Feb 1, pp. 393-400.MantlePlumes
DS1997-0834
1997
Yuen, D.A.Nakakuki, T., Yuen, D.A., Honda, S.The interaction of plumes with the transition zone under continents andoceans.Earth and Planetary Letters, Vol. 146, No. 3/4. Feb 1, pp. 379-392.MantlePlumes
DS1997-1149
1997
Yuen, D.A.Ten, A., Yuen, D.A., Malevsky, A.V.Fractal features in mixing of non-Newtonian and Newtonian mantleconvection.Earth and Planetary Letters, Vol. 146, No. 3/4. Feb 1, pp. 401-414.MantleMixing models
DS1998-0198
1998
Yuen, D.A.Cadek, O., Yuen, D.A., Machetel, P.New perspectives on mantle dynamics from high resolution seismic tomographic model P1200.Pure and Applied Geophys., Vol. 151, No. 2-4, Mar. 1, pp. 503-538.MantleGeophysics - seismics, Geodynamics
DS1998-1619
1998
Yuen, D.A.Yuen, D.A.Plumes originating from the transition zone: dynamical consequences on thermal and geochemical evolution.Geological Society of America (GSA) Annual Meeting, abstract. only, p.A208.MantlePlumes
DS1999-0394
1999
Yuen, D.A.Larsen, T.B., Yuen, D.A., Storey, M.Ultrafast mantle plumes and implications for flood basalt volcanism in the northern Atlantic region.Tectonophysics, Vol. 311, No. 1-4, Sept. 30, pp. 31-82.Baltic States, Quebec, Ungava, Finland, Sweden, NorwayMantle plumes, Flood basalts - review
DS1999-0635
1999
Yuen, D.A.Schott, B., Yuen, D.A., Schmeling, H.Viscous heating in heterogeneous media as applied to the thermal interaction between crust and mantle.Geophysical Research. Lett., Vol. 26, No. 4, Feb. 15, pp. 513-16.MantleGeothermometry
DS2000-0116
2000
Yuen, D.A.Brunet, D., Yuen, D.A.Mantle plumes pinched in the transition zoneEarth and Planetary Science Letters, Vol. 178, No. 1-2, May 15, pp.13-28.MantleMantle plumes, Genesis
DS2000-0194
2000
Yuen, D.A.Cserepes, L., Yuen, D.A.On the possibility of a second kind of mantle plumeEarth and Planetary Science Letters, Vol.183, No.1-2, Nov.30, pp.61-71.MantlePlumes, Hot spots
DS2000-0195
2000
Yuen, D.A.Cserepes, L., Yuen, D.A., Schroeder, B.A.Effect of the mid mantle viscosity and phase transition on 3D mantle convection.Physical Earth and Planetary Interiors, Vol. 118, No.1-2, pp. 135-48.MantleGeophysics - seismics
DS2000-0634
2000
Yuen, D.A.Matyska, C., Yuen, D.A.Profiles of the Bulletinen parameter from mantle convection modellingEarth and Planetary Science Letters, Vol. 178, No. 1-2, May 15, pp.39-46.MantleMantle plumes, Convection
DS2000-0810
2000
Yuen, D.A.Regenauer-Lieb, K., Yuen, D.A.Fast mechanisms for the formation of new plate boundariesTectonophysics, Vol.322, No.1-2, July10, pp.53-68.MantleTectonics, Plates
DS2000-0871
2000
Yuen, D.A.Schott, B., Yuen, D.A., Schmeling, H.The diversity of tectonics from fluid dynamical modeling of the lithosphere mantle systemTectonophysics, Vol.322, No.1-2, July10, pp.35-52.MantleTectonics, Geodynamics - model
DS2001-0575
2001
Yuen, D.A.Karato, S-I., Riedel, M.R., Yuen, D.A.Rheological structure and deformation of subducted slabs in the mantle transition zone: implications....Physics of the Earth and Planetary Interiors, Vol. 127, No. 1-4, Dec. 1, pp. 83-108.MantleCirculation, Subduction - geodynamics, rheology
DS2001-0741
2001
Yuen, D.A.Matyska, C., Yuen, D.A.Are mantle plumes adiabatic?Earth and Planetary Science Letters, Vol. 189, No. 3-4, July 15, pp. 165-76.MantlePlumes - thermodynamic, density, heat, pressure
DS2001-0931
2001
Yuen, D.A.Piromallo, C., Vincent, A.P., Yuen, D.A., Morelli, A.Dynamics of the transition zone under Europe inferred from wavelet cross spectra of seismic tomography.Physics of the Earth and Planetary Interiors, Vol. 125, No. 1-4, pp. 125-39.EuropeGeophysics - seismics
DS2001-1181
2001
Yuen, D.A.Van der Berg, A.P., Yuen, D.A., Steinbach, V.The effects of variable thermal conductivity on mantle heat transferGeophysical Research Letters, Vol. 28, No. 5, Mar. 1, pp. 875-8.MantleGeothermometry
DS2002-1014
2002
Yuen, D.A.Matyska, C., Yuen, D.A.Bullen's parameter: a link between seismology and geodynamical modellingEarth and Planetary Science Letters, Vol.198,3-4,pp.471-83., Vol.198,3-4,pp.471-83.GlobalGeodynamics
DS2002-1015
2002
Yuen, D.A.Matyska, C., Yuen, D.A.Bullen's parameter: a link between seismology and geodynamical modellingEarth and Planetary Science Letters, Vol.198,3-4,pp.471-83., Vol.198,3-4,pp.471-83.GlobalGeodynamics
DS2002-1076
2002
Yuen, D.A.Monnereau, M., Yuen, D.A.How flat is the lower mantle temperature gradient?Earth and Planetary Science Letters, Vol. 202, 1, pp.171-183.MantleGeothermometry
DS2002-1637
2002
Yuen, D.A.Van den Berg, A.P., Yuen, D.A., Allwardt, J.R.Non linear effects from variable thermal conductivity and mantle internal heating: implications for melting..Physics of the Earth and Planetary Interiors, Vol.129, 3-4, pp.359-75.MantleMelting - massive and secular cooling
DS2002-1639
2002
Yuen, D.A.Van denberg, A.P., Yuen, D.A.Delayed cooling of the Earth's mantle due to variable thermal conductivity and the formation of low conductivity zone.Earth and Planetary Science Letters, Vol.199,3-4,pp.403-13.MantleGeophysics - conductivity
DS2003-0460
2003
Yuen, D.A.Gerya, T.V., Yuen, D.A.Rayleigh Taylor instabilities from hydration and melting propel 'cold plumes' atEarth and Planetary Science Letters, Vol. 212, 1-2, pp. 47-62.MantleBlank
DS200412-0654
2003
Yuen, D.A.Gerya, T.V., Yuen, D.A.Rayleigh Taylor instabilities from hydration and melting propel 'cold plumes' at subduction zones.Earth and Planetary Science Letters, Vol. 212, 1-2, pp. 47-62.MantleMelting, plumes
DS200412-1764
2004
Yuen, D.A.Schott, B., Yuen, D.A.Influences of dissipation and rheology on mantle plumes coming from the DPrime layer.Physics of the Earth and Planetary Interiors, Vol. 146, 1-2, pp. 139-145.MantleGeodynamics, geothermometry
DS200412-2167
2004
Yuen, D.A.Yanagawa, T.K., Nakada, M., Yuen, D.A.A simplified mantle convection model for thermal conductivity stratification.Physics of the Earth and Planetary Interiors, Vol. 146, 1-2, pp. 163-177.MantleGeothermometry
DS200512-0697
2005
Yuen, D.A.Matyska, C., Yuen, D.A.The importance of radiative heat transfer on superplumes in the lower mantle with the new post perovskite phase change.Earth and Planetary Science Letters, Vol. 234, 1-2, pp. 71-81.MantleGeothermometry
DS200512-1115
2005
Yuen, D.A.Van den Berg, A.P., Rainey, E.S., Yuen, D.A.The combined influence of variable thermal conductivity, temperature and pressure dependent viscosity and core mantle coupling on thermal evolutionPhysics of the Earth and Planetary Interiors, Vol. 149, 3-4, pp. 259-278.MantleGeothermometry
DS200512-1116
2005
Yuen, D.A.Van den Berg, A.P., Rainey, E.S.G., Yuen, D.A.Dependent viscosity and core mantle coupling on thermal evolution.Physics of the Earth and Planetary Interiors, Vol. 149, 3-4, April 15, pp. 259-278.MantleGeothermometry
DS200612-0451
2006
Yuen, D.A.Gerya, T.V., Connolly, J.A.D., Yuen, D.A., Gorczyk, W., Capel, A.M.Seismic implications of mantle wedge plumes.Physics of the Earth and Planetary Interiors, Vol. 156, 1-2, June 16, pp. 59-74.MantleGeophysics - seismic, subduction, tomography, melting
DS200612-0452
2006
Yuen, D.A.Gerya, T.V., Connolly, J.A.D., Yuen, D.A., Gorczyk, W., Capel, A.M.Seismic implications of mantle wedge plumes.Physics of the Earth and Planetary Interiors, Vol. 156, 1-2, pp. 59-74.MantleSubduction zones, tomography, melting
DS200612-0561
2006
Yuen, D.A.Heir Majumder, C.A., Travis, B.J., Belanger, E., Richard, G., Vincent, A.P., Yuen, D.A.Efficient sensitivity analysis for flow and transport in the Earth's crust and mantle.Geophysical Journal International, Vol. 166, 2, pp. 907-922.MantleGeophysics - seismics
DS200612-0882
2006
Yuen, D.A.Matyska, C., Yuen, D.A.Lower mantle dynamics with the post perovskite phase change, radiative thermal conductivity, temperature and depth dependent viscosity.Physics of the Earth and Planetary Interiors, Vol. 154, 2, Feb. 16, pp. 196-207.MantleGeothermometry, core mantle boundary
DS200712-0373
2007
Yuen, D.A.Gorczyk, W., Gerya, T.V., Connolly, J.A.D., Yuen, D.A.Growth and mixing dynamics of mantle wedge plumes.Geology, Vol. 35, 7, pp. 587-590.MantleSubduction
DS200712-0374
2007
Yuen, D.A.Gorczyk, W.A., Gerya, T.V., Connolly, J.A.D., Burg, J-P., Yuen, D.A.Melting and mixing processes in mantle wedges.Plates, Plumes, and Paradigms, 1p. abstract p. A346.MantleMelting
DS200712-0703
2007
Yuen, D.A.Matyska, C., Yuen, D.A.Lower mantle material properties and convection models of multiscale plumes.Plates, plumes and Planetary Processes, pp. 137-164.MantleConvection
DS200712-0743
2007
Yuen, D.A.Monnereau, M., Yuen, D.A.Topology of the post perovskite phase transition and mantle dynamics.Proceedings of National Academy of Sciences USA, Vol. 104, 22, pp. 9156-9161. IngentaMantlePerovskite
DS200712-1025
2006
Yuen, D.A.Spera, F.J., Yuen, D.A., Giles, G.Tradeoffs in chemical and thermal variations in the post perovskite phase transition: mixed phase regions in the deep lower mantle?Physics of the Earth and Planetary Interiors, Vol. 159, 3-4, Dec. pp. 234-246.MantleGeothermometry
DS200812-0399
2008
Yuen, D.A.Gerya, T.V., Connolly, J.A.D., Yuen, D.A.Why is terrestrial subduction one-sided?Geology, Vol. 36, 1, pp. 43-46.MantleSubduction, slab dehydration
DS200812-0472
2007
Yuen, D.A.Hirose, K., Brodholt, J., Lay, T., Yuen, D.A.An introduction to post-perovskite: the last mantle phase transition.AGU American Geophysical Union Monograph, No. 174, pp. 1-8.MantlePerovskite
DS200812-1199
2008
Yuen, D.A.Van der Lee, S., Regenauer Lieb, K., Yuen, D.A.The role of water in connecting past and future episodes of subduction.Earth and Planetary Science Letters, Vol. 273, 1-2, Aug. 30, pp. 15-27.MantleSubduction
DS200812-1200
2008
Yuen, D.A.Van der Lee, S., Regenauer-Lieb, K., Yuen, D.A.The role of water in connecting past and future episodes of subduction.Earth and Planetary Science Letters, Vol. 273, pp. 15-27.MantleSubduction - water
DS200812-1303
2007
Yuen, D.A.Yuen, D.A., Matyska, C., Cadek, O., Kameyama, M.The dynamical influences from physical properties in the lower mantle and post perovskite phase transition.AGU American Geophysical Union Monograph, No. 174, pp. 249-270.MantleTectonics
DS201012-0084
2010
Yuen, D.A.Cadek, O., Yuen, D.A., Cizkova, H.Mantle viscosity inferred from geoid and seismic tomography by genetic algorithms: results for layered mantle flow.Physics and Chemistry of Minerals , Vol. 23, 9-10, pp. 865-872.MantleGeophysics - seismics
DS201012-0794
2010
Yuen, D.A.Tosi, N., Yuen, D.A., Cadek, O.Dynamical consequences in the lower mantle with the post perovskite phase change and strongly depth dependent thermodynamic and transport properties.Earth and Planetary Science Letters, Vol. 298, 1-2, Sept. 15, pp. 229-243.MantleGeothermometry
DS201112-1056
2011
Yuen, D.A.Tosi, N., Yuen, D.A.Bent shaped plumes and horizontal channel flow beneath the 660 km discontinuity.Earth and Planetary Science Letters, Vol. 312, 3-4, pp. 348-359.MantleGeophysics - seismics -not specific to diamonds
DS201412-0939
2014
Yuen, D.A.Van den Berg, A.P., Yuen, D.A.Is the lower mantle rheology Newtonian today?Geophysical Research Letters, Vol. 23, 16, pp. 2033-20136.MantleRheology
DS201503-0177
2015
Yuen, D.A.So, B-D., Yuen, D.A.Generation of tectonic over-pressure inside subducting oceanic lithosphere involving phase-loop of olivine-wadsleyite transition.Earth and Planetary Science Letters, Vol. 413, March 1, pp. 59-69.MantleSubduction
DS201506-0278
2015
Yuen, D.A.Justo, J.F., Morra, G., Yuen, D.A.Viscosity undulations in the lower mantle: the dynamical role of iron spin transition.Earth and Planetary Science Letters, Vol. 421, pp. 20-26.MantleCore
DS1990-1617
1990
Yuequn JinYuequn Jin, Taylor, L.A.Secondary textures in spinel peridotite xenoliths in Cenozoic basalts from eastern China: mantle process or surface phenomenon?International Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 805-807ChinaXenoliths, Basalt
DS1990-1618
1990
Yuequn JinYuequn Jin, Taylor, L.A.Probing into the mantle and crust through a South Pacific hot-spot: a studyof xenoliths from Tahiti, Society IslandsInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 807-808GlobalMantle, Xenoliths
DS2000-0940
2000
YufangSu, Yufang, Slottow, J., Mosea, A.Distributing proprietary geographic dat a on the World Wide Web - UCLA GIS dat abase and map server.Comp. and Geosc., Vol. 26, No. 7, pp. 741-50.GlobalComputer - GIS
DS1994-1576
1994
Yugan JinShangyou Nie, An Yin, Rowley, D.B., Yugan JinExhumation of the Dabie Shan ultra high pressure rocks and accumulation Of the Songpan Ganzi flysch sequence.Geology, Vol. 22, No. 11, November pp. 999-1002.ChinaMetamorphic rocks, Diamonds
DS201112-1122
2011
Yuhara, M.Wu, F-Y., Yang, Y-H.,Li, Q-L., Mitchell, R.H., Dawson, J.B., Brandl, G., Yuhara, M.In situ determination of U-Pb ages and Sr-Nd-Hf isotopic constraints on the petrogenesis of the Phalaborwa carbonatites complex, South Africa.Lithos, Vol. 127, 1-2, pp. 309-322.Africa, South AfricaCarbonatite, geochronology, Palaborwa
DS2003-1308
2003
YuiSobolev, N.V., Shatsky, V.S., Liou, J.G., Zhang, R.Y., Hwang, Shen, Chu, YuiAn origin of microdiamonds in metamorphic rocks of the Kokchetav Massif, northernEpisodes, Russia, KazakhstanBlank
DS200412-1871
2003
YuiSobolev, N.V., Shatsky, V.S., Liou, J.G., Zhang, R.Y., Hwang, Shen, Chu, Yui, Zayachkovsky, KasymovAn origin of microdiamonds in metamorphic rocks of the Kokchetav Massif, northern Kazakhstan. US Russian civilian research andEpisodes, December, pp. 290-294.Russia, KazakhstanGenesis - microdiamonds
DS200512-0455
2004
YuiHwang, S.L., Shen, P., Chu, H-T., Yui, T-F, Liou, J.G., Sobolev, N.V., Zhang, R-Y., Shatsky, V.S., ZayachkovskyKokchetavite: a new potassium feldspar polymorph from the Kokchetav ultrahigh pressure terrane.Contributions to Mineralogy and Petrology, Vol. 148, 3, pp. 380-RussiaUHP
DS200512-1247
2005
YuiZhang, 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
DS201112-1164
2011
Yui, F.Zhang, Z.M., Dong, X., Liou, J.G., Liu, F., Wang, W., Yui, F.Metasomatism of garnet periodite from Jiangzhuang, Sulu UHP belt: constraints on the interactions between crust and mantle rocks during subduction of cont. lithosphereJournal of Metamorphic Geology, in press availableChinaUHP
DS201112-1165
2011
Yui, F.Zhang, Z.M., Dong, X., Liou, J.G., Liu, F., Wang, W., Yui, F.Metasomatism of garnet peridotite from Jiangzhuang, southern Sulu UHP belt: constraints on the interactions between crust and mantle rocks during subduction of continentalJournal of Metamorphic Geology, Vol. 29, 9, pp. 917-937.ChinaUHP
DS1995-2111
1995
Yui, T.F.Yui, T.F., Rumble, D., Lo, C.H.Unusually low Delta O ultra high pressure metamorphic rocks from the SuluTerrain, eastern China.Geochimica et Cosmochimica Acta, Vol. 59, No. 13, July pp. 2859-2864.ChinaMetamorphic rocks, Sulu Terrain
DS1996-0673
1996
Yui, T.F.Jahn, B., Comichet, J., Yui, T.F.Ultrahigh epsilon neodymium eclogites from an ultrahigh pressure metamorphic terrane of China.Chemical Geology, Vol. 127, No. 1-3, Jan. 10, pp. 61-80.ChinaEclogites, Metamorphic rocks
DS1997-1285
1997
Yui, T.F.Yui, T.F., Riumble, C.H., Chen, C.H., Lo, C.H.Stable isotope characteristics of eclogites from the ultra-high pressure metamorphic terrain, China.Chemical Geology, Vol. 137, No. 1-2, May 1, pp. 135-148.China, east centralGeochronology, Eclogites
DS2001-0497
2001
Yui, T.F.Hwang, S.L., Shen, P., Yui, T.F., Chu, H.T.Defect microstructures of minerals as a potential indicator of extreme melt rapid and episodic exhumationEarth and Planetary Science Letters, Vol. 192, No. 1, pp. 57-63.Chinaultra high pressure (UHP) - ultrahigh pressure metamorphic rock, Orogens - continental collision
DS2003-0607
2003
Yui, T.F.Huang, S.L., Shen, P., Yui, T.F., Chu, H.T.Metal sulfur COH silicate fluid mediated diamond nucleation in Kokchetav ultra highEuropen Journal of Mineralogy, Vol. 15, 3, pp. 503-512.Russia, Kola PeninsulaBlank
DS200412-0856
2003
Yui, T.F.Huang, S.L., Shen, P., Yui, T.F., Chu, H.T.Metal sulfur COH silicate fluid mediated diamond nucleation in Kokchetav ultra high pressure gneiss.European Journal of Mineralogy., Vol. 15, 3, pp. 503-512.Russia, Kola PeninsulaUHP
DS200512-0473
2005
Yui, T.F.Jahn, B., Liu, X., Yui, T.F., Morin, N., Coz, M.B.High pressure/ultrahigh pressure eclogites from the Hongan Block, east central China: geochemical characterization, isotope disequilibrium, geochronologyContributions to Mineralogy and Petrology, Vol. 149, 5, pp. 499-526.Asia, ChinaUHP
DS201812-2819
2018
Yui, T.F.Hwang, S.L., Shen, P., Yui, T.F., Chu, H.T., Logvinova, A.M., Sobolev, N.V.Low energy phase boundary pairs and preferred crystallographic orientations of olivines in nanometer-sized ultrapotassic fluid inclusions of Aykhal diamond.Lithos, Vol. 322, pp. 392-404.Russiadeposit - Aykhal

Abstract: The healed internal conjugated cleavages at the core of Aykhal octahedral diamond sample AH2 were decorated with {111}dia-facetted ultrapotassic fluid/melt inclusion pockets containing nanosized graphite, phlogopite and olivine (Fo92) inclusions. These olivines are either rounded in pockets with ample fluid, or facetted by the {111}dia mold in the pockets with a fluid film. Transmission electron microscopy revealed two distinct crystallographic characteristics of olivine inclusions: (1) pronounced crystallographic texture of olivines grouped in specific diamond domain, and (2) frequent parallelism or sub-parallelism of specific low-energy faces of the two phases, mainly (010)ol, {120}ol, (001)ol and {111}dia, {110}dia, {100}dia in the order of decreasing preference, forming prominent (010)ol/{111}dia, (010)ol/{110}dia, (001)ol/{110}dia, {120}ol/{111}dia, and {120}ol/{110}dia low-energy phase boundaries with thin liquid film of 1-2?nm in between. These findings not only testify to the extremely low adhesion energies of olivine-diamond boundary pairs, but also imply that, in the presence of a fluid phase, the interfacial energetics and the energetically favored crystallographic orientations of olivine inclusions in diamond can be controlled simply by the settlement/attachment of low-energy facets of olivine crystals precipitating from the parental fluid upon the low-energy {111}dia or {110}dia surfaces of diamond. Such interfacial energetics control and the resultant low-energy boundary pairs are characteristically distinct from the common topotaxy or epitaxy between oxide/silicate mineral pairs, but are in a sense like the Van der Waals heteroepitaxy in artificial systems.
DS200512-0454
2005
Yui, T-F.Hwang, S.L., Shen, P., Chu, H-T., Yui, T-F., Liou, J.G., Sobolev, N.V., Shatsky, V.S.Crust derived potassic fluid in metamorphic microdiamond.Earth and Planetary Science Letters, Vol. 231, 3-4, March 15, pp. 295-306.Russia, SiberiaKokchetav massif
DS200512-0474
2005
Yui, T-F.Jahn, B-M., Liu, X., Yui, T-F., Morin, N., Bouhnik-Le Coz, M.High pressure ultrahigh pressure eclogites from the Hong an Block, east central China: geochemical characterization, isotope disequilibrium and geochronological controversy.Contributions to Mineralogy and Petrology, On lineChinaUHP
DS200612-0613
2006
Yui, T-F.Hwang, S.L., Chu, H-T., Yui, T-F., Shen, P., Schertl, H-P., Liou, J.G., Sobolev, N.V.Nanometer size P/K rich silica glass (former melt) inclusions in microdiamond from the gneisses of Kokchetav and Erzgebirge massifs: diversified...Earth and Planetary Science Letters, in pressRussia, Europe, GermanyUHP metamorphic microdiamonds, host rock buffering
DS200712-1228
2007
Yui, T-F.Zhang, R.Y., Li, T., Rumble, D., Yui, T-F., Li, L., Yang, J.S., Pan, Y., Liou, J.G.Multiple metasomatism in Sulu ultrahigh P garnet peridotite constrained by petrological geochemiscal investigations.Journal of Metamorphic Geology, Vol. 25, 2, pp. 149-164..ChinaUHP
DS201012-0300
2010
Yui, T-F.Hwang, S-L., Yui, T-F., Chu, H-T., Shen, P., Zhang, R-Y., Liou, J.G.An AEM study of garnet clinopyroxenite from the Sulu ultrahigh pressure terrane: formation mechanisms of oriented ilmenite, spinel, magnetite, amphibole andContributions to Mineralogy and Petrology, in press available, 14p.TechnologyUHP, Garnet inclusions in clinopyroxenes
DS201112-0460
2011
Yui, T-F.Hwang, S-L., Yui, T-F., Chu, H-T., Shen, P., Zhang, R-Y., Liou, J.G.An AEM study of garnet clinopyroxenite from the Sulu ultrahigh pressure terrane: formation mechanisms of oriented ilmenite, spinel, magnetite, amphibole garnetContributions to Mineralogy and Petrology, Vol. 161, 6, pp. 901-920.MantleChemistry
DS201505-0251
2015
Yui, T-F.Hwang, S-L., Shen, P., Chu, H-T., Yui, T-F., Lizuka, Y.Origin of rutile needles in star garnet and implications for interpreation of inclusion textures in ultrahigh pressure metamorphic rocks.Journal of Metamorphic Geology, Vol. Pp. 249-272.TechnologyUHP
DS2000-0855
2000
Yujing, H.Sassi, R., Harte, B., Carswell, D.A., Yujing, H.Trace element distribution in Central Dabie eclogitesContributions to Mineralogy and Petrology, Vol. 139, No. 3, pp. 298-315.China, east central ChinaEclogites, petrology, Dabie Shan, Deposit - Dabie Shan
DS2002-0360
2002
Yujing, H.Dawer, M., Xiuling, W., Yujing, H., Xin, M.Ultra structure of coesite - retrogressive metamorphic quartz and their interface transition belt from ultra high pressure metamorphic rocks.18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.72.MantleUHP, mineralogy, coesite
DS1993-0978
1993
Yujun YinMasaki Enami, Quija Zang, Yujun Yinhigh pressure eclogites in northern Jiangsu -southern Shandong Province, eastern China.Journal of Metamorphic Geology, Vol. 11, pp. 589-603.ChinaEclogites, metamorphism
DS1975-0707
1978
Yuki, H.Brummer, J.J., Yuki, H.Diamond Deposits in CanadaGemmol. Soc. Japan., Vol. 5, No. 3, PP. 26-28.GlobalDiamond Occurrences
DS1997-1286
1997
Yukon Mining and Exploration OverviewYukon Mining and Exploration OverviewYukon Field work and property descriptionsYukon Mining and Exploration Overview, YukonBook - table of contents, Fieldwork - exploration, properties
DS1860-0071
1868
Yule, H.Yule, H.Indian Diamonds 1868London: Hakluyt Soc. Publishing, P. 20.IndiaDiamond Occurrence
DS1860-0610
1888
Yule, H.Yule, H.The History of the Pitt DiamondLondon:, IndiaDiamonds Notable
DS200412-1113
2004
Yulong, L.Lei, Z., Jinhua, H., Yifei, D., Yulong, L.Assortment of deep mantle fluids and their products in kimberlites from China.Acta Geologica Sinica, Vol. 78, 1, pp. 118-120.ChinaGeochemistry, mineral chemistry
DS1994-1972
1994
Yulsman, T.Yulsman, T.Lost in the outback... Bungle Bungle Massif...Earth, December pp. 24-34.AustraliaKimberley region -layman's overview
DS1995-1743
1995
Yulsman, T.Shurkin, J., Yulsman, T.Assembling Asia.... migrating chains of volcanoesEarth, Vol. 4, No. 3, June pp. 52-59.AsiaTectonics, Gondwanaland
DS1991-1915
1991
Yund, R.A.Yund, R.A., Tullis, J.Compositional changes of minerals associated with dynamicrecrystallizationContributions to Mineralogy and Petrology, Vol. 108, pp. 346-355GlobalMineralogy, Structure/deformation
DS201809-2016
2018
YunfeiDuan, 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.
DS2003-1568
2003
Yupeng YaoZou, H.,Reid, M.R., Yongshun Liu, Yupeng Yao, Xisheng Xu, Qicheng FanConstraints on the origin of historic potassic basalts from northeast Chin a by U ThChemical Geology, Vol. 200, 1-2, Oct. 16, pp. 189-201.ChinaPhlogopite garnet bearing peridotite, melting, metasoma
DS200412-2239
2003
Yupeng YaoZou, H.,Reid, M.R., Yongshun Liu, Yupeng Yao, Xisheng Xu, Qicheng FanConstraints on the origin of historic potassic basalts from northeast Chin a by U Th disequilibrium data.Chemical Geology, Vol. 200, 1-2, Oct. 16, pp. 189-201.ChinaPhlogopite garnet bearing peridotite, melting, metasoma
DS200612-1581
2001
Yuqi, C.Yuqi, C.Concise regional geology of China. english versionGeological Publishing House, $ 80. US email gphzhj @hotmail.comChinaBook - geology
DS2001-1209
2001
YurevaVotyakov, S.L., Shchapova, Y.V., Chashchukhin, YurevaMetal oxygen bond ionicity in Cr spinels: quantum chemical calculation dataDoklady, Vol.383, No. 1-2, Feb-Mar. pp. 211-4.GlobalGeochemistry - chromium spinels, experimental geochemistry
DS201603-0434
2015
Yureva, O.P.Yureva, O.P., Rakhmanova, M.I., Nadolinny, V.A., Zedgenizov, D.A., Shatsjy, V.S., Kagi, H., Komarovskikh, A.Y.The characteristic photoluminesence and EPR features of super deep diamonds ( Sao-Luis, Brazil).Physics and Chemistry of Minerals, Vol. 42, 9, pp. 707-722.South America, BrazilDeposit - Sao-Luis

Abstract: Photoluminescence (PL) spectroscopy and electron paramagnetic resonance (EPR) were used for the first time to characterize properties of superdeep diamonds from the São-Luis alluvial deposits (Brazil). The infrared measurements showed the low nitrogen content (>50 of 87 diamonds from this locality were nitrogen free and belonged to type IIa) and simultaneously the extremely high level of nitrogen aggregation (pure type IaB being predominant), which indicates that diamonds under study might have formed under high pressure and temperature conditions. In most cases, PL features excited at various wavelengths (313, 473, and 532 nm) were indicative of different growth and post-growth processes during which PL centers could be formed via interaction between vacancies and nitrogen atoms. The overall presence of the 490.7 nm, H3, and H4 centers in the luminescence spectra attests to strong plastic deformations in these diamonds. The neutral vacancy known as the GR1 center has probably occurred in a number of crystals due to radiation damage in the post-growth period. The 558.5 nm PL center is found to be one of the most common defects in type IIa samples which is accompanied by the EPR center with g-factor of 2.00285. The 536 and 576 nm vibronic systems totally dominated the PL spectra of superdeep diamonds, while none of “normal” diamonds from the Mir pipe (Yakutia) with similar nitrogen characteristics showed the latter three PL centers.
DS200712-0307
2007
Yurevich, S.M.Fedorovich, A.N., Yurevich, S.M., Iljich,R.A.Prediction of and searching for kimberlites by multispectral satellite images (MSI) on the basis of the stability theory of frames and encoding images.IAGOD Meeting held August 2006, Abstract, 5p.TechnologyRemote sensing - hyperspectral
DS200712-1211
2006
Yurevich, S.M.Yurevich, S.M., Sergeevich, S.V.The contribution of remote sensing to diamond deposit prospecting on the Russian plate.IAGOD Meeting held August 2006, Abstract 1p.RussiaRemote sensing
DS1995-2026
1995
YurimotoWang, W., Takahashi, E., Yurimoto, SueonoInfluence of chromium on rare earth elements (REE) partition behaviour between garnet and basaltic melt.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 666-668.GlobalPetrology -experimental, rare earth elements (REE) -garnets
DS2002-1113
2002
YurimotoMurakami, M., Hirose, K., Yurimoto, Nakashima, TakafujiWater in Earth's lower mantleScience, No. 5561, Mar. 8, pp. 1885-6.MantleWater
DS2002-1175
2002
YurimotoO'Hara, Y., Stern, Ishii, Yurimoto, YamazakiPeridotites from the Mariana Trough: first look at the mantle beneath an active back-arc basin.Contribution to Mineralogy and Petrology, Vol.143,1,pp.1-18., Vol.143,1,pp.1-18.Mariana TroughPeridotites
DS2002-1176
2002
YurimotoO'Hara, Y., Stern, Ishii, Yurimoto, YamazakiPeridotites from the Mariana Trough: first look at the mantle beneath an active back-arc basin.Contribution to Mineralogy and Petrology, Vol.143,1,pp.1-18., Vol.143,1,pp.1-18.Mariana TroughPeridotites
DS1987-0824
1987
Yurimoto, H.Yurimoto, H., Sueno, S.Anion and cation partitioning between three pyroxenes, chrome spinel phenocrysts and the host boninite magma: an ion microprobe studyGeochemical Journal, Vol. 21, No. 3, pp. 85-104GlobalBlank
DS1990-0893
1990
Yurimoto, H.Kurosawa, M., Yurimoto, H., Sueno, S.Hydrogen distribution in San Carlos olivine #2International Mineralogical Association Meeting Held June, 1990 Beijing, Vol. 2, extended abstract p. 808-810CaliforniaPetrology, Olivines
DS1990-0894
1990
Yurimoto, H.Kurosawa, M., Yurimoto, H., Sueno, S., Matsumoto, K.Hydrogen distribution in San Carlos olivine #1Eos, Vol. 71, No. 28, July 10, p. 903. AbstractNew MexicoMantle, San Carlos olivine
DS1995-1933
1995
Yurimoto, H.Tsunogae, T., Yurimoto, H.Single zircon uranium-lead (U-Pb) geochronology of the Limpopo Belt by secondary ion massspectrometryGeochemical Journal, Vol. 29, No. 3, pp. 197-206South AfricaGeochronology, Limpopo Belt
DS1996-1505
1996
Yurimoto, H.Wang, W., Yurimoto, H., Sueno, S.rare earth elements (REE) in mantle garnets and mantle MetasomatismInternational Geological Congress 30th Session Beijing, Abstracts, Vol. 2, p. 393.MantleGeothermometry
DS1997-0867
1997
Yurimoto, H.Ohtani, E., Yurimoto, H., Seto, S.Element partitioning between metallic liquid, silicate liquid and Lower Mantle mineral: implications for corePhysics of the Earth and Plan. Interiros, Vol. 100, pp. 97-114.MantleGeothermometry, Heat transport, silicates
DS1997-1224
1997
Yurimoto, H.Wang, W., Sueno, S., Yurimoto, H., Takahashi, E.Geochemical study of eclogitic mineral inclusions from Chinese diamondsProceedings 30th. I.G.C., Pt. 15, pp. 185-198.ChinaEclogite, Diamond inclusions
DS1998-0004
1998
Yurimoto, H.Abe, N., Arai, S., Yurimoto, H.Petrology of the arc peridotite xenoliths: implications for geochemical evolution of the wedge mantle.7th International Kimberlite Conference Abstract, pp. 4-6.MantleXenoliths, Subduction
DS2000-0004
2000
Yurimoto, H.Abe, N., Arai, S., Shcheka, S., Yurimoto, H.Petrology of harzburgite and related xenoliths from Avacha volcano, Kamchatka Arc and its implication for..Igc 30th. Brasil, Aug. abstract only 1p.RussiaMantle - wedge mantle processes, Xenoliths
DS2001-0039
2001
Yurimoto, H.Arai, S., Kida, M., Abe, M., Yurimoto, H.Petrology of peridotite xenoliths in alkali basalt ( 11 Ma) from Boun, Korea: insight into upper mantle....Journal of Min. Petrol. Sciences, Vol. 96, No. 3, pp. 89-99.GlobalMantle mineralogy - East Asian continental margin
DS2002-0871
2002
Yurimoto, H.Komiya, T., Hayashi, M., Maryyama, S., Yurimoto, H.Intermediate P T type Archean metamorphism of the Isua supracrustal beltAmerican Journal of Science, Vol. 302, 9, pp. 806-26.GreenlandSubduction
DS2002-0872
2002
Yurimoto, H.Komiya, T., Maruyama, S., Hirata, T., Yurimoto, H.Petrology and geochemistry of MORB and OIB in the mid-Archean north pole regionInternational Geology Review, Vol. 44, No. 11, Nov. pp. 988-1016.Australia, westernMantle - geochronology
DS2003-0823
2003
Yurimoto, H.Litasov, K., Ohtani, E., Langenhorst, F., Yurimoto, H., Kubo, T., Kondo, T.Water solubility in Mg perovskites and water storage capacity in the lower mantleEarth and Planetary Science Letters, Vol. 211, 1-2, June 15, pp. 189-203.MantleWater storage
DS2003-0824
2003
Yurimoto, H.Litasov, K., Ohtani, E., Langenhorst, F., Yurimoto, H., Kubo, T., Kondo, T.Water solubility in Mg perovskites and water storage capacity in the lower mantleEarth and Planetary Science Letters, Vol. 211, 1-2, pp. 189-203.MantleBlank
DS200412-0960
2003
Yurimoto, H.Katayama, I., Hirose, K., Yurimoto, H., Nakashima, S.Water solubility in majoritic garnet in subducting oceanic crust.Geophysical Research Letters, Vol. 22, SDE 2 Nov. 15, 10.1029/2003 GLO18127MantleGeochemistry - subduction
DS200412-1144
2003
Yurimoto, H.Litasov, K., Ohtani, E., Langenhorst, F., Yurimoto, H., Kubo, T., Kondo, T.Water solubility in Mg perovskites and water storage capacity in the lower mantle.Earth and Planetary Science Letters, Vol. 211, 1-2, June 15, pp. 189-203.MantleWater storage
DS200512-0498
2005
Yurimoto, H.Katayama, I., Nakashima, S., Yurimoto, H.Water content in natural eclogite and implication for water transport into deep upper mantle.Lithos, In press,RussiaKokchetav Massif, UHP, subduction
DS200612-0669
2006
Yurimoto, H.Katayama, I., Nakashima, S., Yurimoto, H.Water content in natural eclogite and implications for water transport into the deep upper mantle.Lithos, Vol. 86, 3-4, Feb. pp. 245-259.Mantle, RussiaSprectroscopy, Kokchetav Massif, subduction, diamond
DS201312-0427
2013
Yurimoto, H.Imamura, K., Ogasawara, Y., Yurimoto, H., Kusakabe, M.Carbon isotope heterogeneity in metamorphic diamond from the Kokchetav UHP dolomite marble, northern Kazakhstan.International Geology Review, Vol. 55, 4, pp. 453-467.Russia, KazakhstanDeposit- Kokchetav
DS201603-0368
2015
Yurimoto, H.Chang, Y-Y., Jacobsen, S.D., Bina, C.R., Thomas, S-M., Smyth, J.R., Frost, D.J., Boffa Ballaran, T., McCammon, C.A., Hauri, E.H., Inoue, T., Yurimoto, H., Meng, Y., Dera, P.Comparative compressibility of hydrous wadsleyite and ringwoodite: effect of H2O and implications for detecting water in the transition zone.Journal of Geophysical Research,, Vol. 120, 12, pp. 8259-8280.MantleRingwoodite

Abstract: Review of recent mineral physics literature shows consistent trends for the influence of Fe and H2O on the bulk modulus (K0) of wadsleyite and ringwoodite, the major phases of Earth's mantle transition zone (410-660?km). However, there is little consensus on the first pressure derivative, K0??=?(dK/dP)P=0, which ranges from about 4 to >5 across experimental studies and compositions. Here we demonstrate the importance of K0? in evaluating the bulk sound velocity of the transition zone in terms of water content and provide new constraints on the effect of H2O on K0? for wadsleyite and ringwoodite by conducting a comparative compressibility study. In the experiment, multiple crystals of hydrous Fo90 wadsleyite containing 2.0 and 0.25?wt?% H2O were loaded into the same diamond anvil cell, along with hydrous ringwoodite containing 1.4?wt?% H2O. By measuring their pressure-volume evolution simultaneously up to 32?GPa, we constrain the difference in K0? independent of the pressure scale, finding that H2O has no effect on K0?, whereas the effect of H2O on K0 is significant. The fitted K0? values of hydrous wadsleyite (0.25 and 2.0?wt?% H2O) and hydrous ringwoodite (1.4?wt?% H2O) examined in this study were found to be identical within uncertainty, with K0? ~3.7(2). New secondary-ion mass spectrometry measurements of the H2O content of these and previously investigated wadsleyite samples shows the bulk modulus of wadsleyite is reduced by 7.0(5)?GPa/wt?% H2O, independent of Fe content for upper mantle compositions. Because K0? is unaffected by H2O, the reduction of bulk sound velocity in very hydrous regions of transition zone is expected to be on the order of 1.6%, which is potentially detectible in high-resolution, regional seismology studies.
DS201910-2312
2019
Yurimoto, H.Zedgenizov, D.A., Ragozin, A.L., Kagi, H., Yurimoto, H., Shatsky, V. S.SiO2 inclusions in sublithospheric diamonds.Geochemistry International, Vol. 57, 9, pp. 964-972.Mantlediamond inclusions

Abstract: The paper describes mineralogical characteristics of SiO2 inclusions in sublithospheric diamonds, which typically have complicated growth histories showing alternating episodes of growth, dissolution, and postgrowth deformation and crushing processes. Nitrogen contents in all of the crystals do not exceed 71 ppm, and nitrogen is detected exclusively as B-defects. The carbon isotope composition of the diamonds varies from ?13? = -26.5 to -6.7‰. The SiO2 inclusions occur in association with omphacitic clinopyroxenes, majoritic garnets, CaSiO3, jeffbenite, and ferropericlase. All SiO2 inclusions are coesite, which is often associated with micro-blocks of kyanite in the same inclusions. It was suggested that these phases have been produced by the retrograde dissolution of primary Al-stishovite, which is also evidenced by the significant internal stresses in the inclusions and by deformations around them. The oxygen isotope composition of SiO2 inclusions in sublithospheric diamonds (?18O up to 12.9‰) indicates a crustal origin of the protoliths. The negative correlation between the ?18O of the SiO2 inclusions and the ?13C of their host diamonds reflects interaction processes between slab-derived melts and reduced mantle rocks at depths greater than 270 km.
DS202106-0973
2021
Yurimoto, H.Tagawa, S., Sakamoto, N., Hirose, K., Hernlund, J., Ohishi, Y., Yurimoto, H.Experimental evidence for more hydrogen in Earth's core than in the oceans.Nature Communications, doi.org/10.1038/s41467-021-22035-0 Vol. 12 8p. PdfMantlehydrogen

Abstract: Hydrogen is one of the possible alloying elements in the Earth’s core, but its siderophile (iron-loving) nature is debated. Here we experimentally examined the partitioning of hydrogen between molten iron and silicate melt at 30-60 gigapascals and 3100-4600?kelvin. We find that hydrogen has a metal/silicate partition coefficient DH???29 and is therefore strongly siderophile at conditions of core formation. Unless water was delivered only in the final stage of accretion, core formation scenarios suggest that 0.3-0.6?wt% H was incorporated into the core, leaving a relatively small residual H2O concentration in silicates. This amount of H explains 30-60% of the density deficit and sound velocity excess of the outer core relative to pure iron. Our results also suggest that hydrogen may be an important constituent in the metallic cores of any terrestrial planet or moon having a mass in excess of ~10% of the Earth.
DS1995-1857
1995
Yurin, Yu.A.Suvarov, V.D., Yurin, Yu.A., Parasotka, B.S.Structure of the lower earth's crust and upper mantle of the western partof the Yakutian Diamondiferous provRussian Geology and Geophysics, Vol. 35, No. 11, pp. 107-Russia, YakutiaGeophysices -seismics, Diamondiferous province
DS1995-1858
1995
Yurin, Yu.A.Suvorov, V.D., Timirshin, K.V., Yurin, Yu.A., et al.Structure and evolution of the crust and uppermost mantle beneath Yakutian kimberlite Province -seismic dat a #1Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 592-593.Russia, YakutiaStructure, Geophysics -seismics
DS1997-1128
1997
Yurin, Yu.A.Suvorov, V.D., Yurin, Yu.A., Timirshin, K.V., et al.Structure and evolution of the crust and uppermost mantle beneath Yakutian kimberlite province -seismics #2Russian Geology and Geophysics, Vol. 38, No. 2, pp. 518-527.Russia, YakutiaStructure, geodynamics, Geophysics - seismics
DS200912-0529
2009
Yurjeva, O.P.Nadolinny, V.A., Yurjeva, O.P., Pokhilenko, N.P.EPR and luminescence dat a on the nitrogen aggregation in diamonds from Snap Lake dyke system.Lithos, In press - available 19p.Canada, Northwest TerritoriesDeposit - Snap Lake
DS1985-0758
1985
Yurkevich, Y.R.Yurkevich, Y.R.Large scale helicopter geochemical surveys in regions bearing Kimberlite pipes recovered from trap rocks.(Russian)Izv. Vyss. Uch. Zaved. Geol., (Russian), No. 2, pp. 122-124RussiaGeochemistry, Kimberlite
DS1985-0759
1985
Yurkevich, Y.R.Yurkevich, Y.R.Structural and tectonic localization of manifestation of kimberliticmagmatism.(Russian)Izvest. Vyss. Uch. Zaved., (Russian), No. 3, pp. 112-113RussiaRemote Sensing, Kimberlite
DS1981-0439
1981
Yurkevich, YU.R.Yurkevich, YU.R.Results of Gas Dat a in the Yakutia Kimberlite Province, on Trap Covered Surfaces.Izvest. Vyssh. Uched. Zaved. Geol. I. Raznd., No. 1, PP. 137-138.RussiaOrigin
DS1986-0845
1986
Yurkevich, Yu.R.Vorobev, S.A., Yurkevich, Yu.R.Geochemical prospecting for kimberlites under basaltic flows.(Russian)Izv. Vyssh. Uchen. Zaved. Geol. Razved.(Russian), No. 9, pp. 57-64RussiaGeochemistry, Prospecting
DS1987-0825
1987
Yurkevich, Yu.R.Yurkevich, Yu.R.Morphostructural analysis of kimberlite fields.(Russian)Razvedka I Okhrana Nedr., (Russian), Vol. 1987, No. 2, pp. 25-26RussiaBlank
DS201112-1156
2011
YuryevaZedgenizov, 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
DS202010-1852
2020
Yuryeva, O.Komarovskikh, A., Rakhmanova, M., Yuryeva, O., Nadolinny, V.Infrared, photoluminescence, and electron paramagnetic resonance characteristic features of diamonds from Aikhal pipe, (Yakutia).Diamond & Related Materials, Vol. 109, 108045, 9p. PdfRussiadeposit - Aikhal

Abstract: The diversity of the defects in the collection (50 samples) of diamonds from the Aikhal pipe (Yakutia) has been studied with IR, PL, and EPR spectroscopy. The specific features of crystals have been established; the obtained information leads to the discussion about the diamond formation and growth conditions. One of the specific features observed is a high concentration of platelets. According to the platelet behavior, most of the crystals are regular suggesting the growth temperature to be 1100-1200 °C. The concentrations of A and B defects have been evaluated and the same temperature conditions have been obtained according to the Taylor diagram. Using the EPR spectroscopy, the C and N3V centers have been found in many crystals suggesting the aggregation of nitrogen during residence in the mantle at high temperatures. An interesting feature has been observed in the PL spectra. For most crystals, the spectrum with ZPL at 563.5 nm is very intensive. The structure of the observed defect is remaining unknown, the spectrum disappears as a result of annealing at 600 °C indicating the interstitial-vacancy annihilation mechanism.
DS202012-2224
2020
Yuryeva, O.Komarovskikh, A., Rakmanova, M., Yuryeva, O., Nadolinny, V.Infrared, photoluminescence, and electron paramagnetic resonance characteristic features of diamonds from the Aikhal pipe ( Yakutia).Diamond and Related Materials, Vol. 109, 108045, 9p. PdfRussiadeposit - Aikhal

Abstract: The diversity of the defects in the collection (50 samples) of diamonds from the Aikhal pipe (Yakutia) has been studied with IR, PL, and EPR spectroscopy. The specific features of crystals have been established; the obtained information leads to the discussion about the diamond formation and growth conditions. One of the specific features observed is a high concentration of platelets. According to the platelet behavior, most of the crystals are regular suggesting the growth temperature to be 1100-1200 °C. The concentrations of A and B defects have been evaluated and the same temperature conditions have been obtained according to the Taylor diagram. Using the EPR spectroscopy, the C and N3V centers have been found in many crystals suggesting the aggregation of nitrogen during residence in the mantle at high temperatures. An interesting feature has been observed in the PL spectra. For most crystals, the spectrum with ZPL at 563.5 nm is very intensive. The structure of the observed defect is remaining unknown, the spectrum disappears as a result of annealing at 600 °C indicating the interstitial-vacancy annihilation mechanism.
DS2003-0991
2003
Yuryeva, O.P.Nadolinny, V.A., Shatsky, V.S., Sobolev, N.V., Twitchen, D.J., Yuryeva, O.P.Observation and interpretation of paramagnetic defects in Brazilian and Central AfricanAmerican Mineralogist, Vol.88, pp. 11-17.Brazil, Central African RepublicSpectroscopy - nitrogen
DS201212-0507
2012
Yuryeva, O.P.Nadolinny, V.A., Yuryeva,O.P., Rakhmanova, M.I., Shatsky, V.S., Palyanov, Y.N., Kupriyanov, I.N., Zedgenizov, D.A., Ragozin, A.L.Distribution of OK1, N3 and NU1 defects in diamond crystals of different habits.European Journal of Mineralogy, Vol. 24, 4, pp. 645-650.TechnologyDiamond morphology
DS201412-0721
2014
Yuryeva, O.P.Rakhmanova, M.I., Nadolinny, V.A., Yuryeva, O.P., Pokhilenko, N.P.Pecularities of nitrogen impurity aggregation in diamonds from the Sytykanskaya pipe, Yakutia.European Journal of Mineralogy, Vol. 27, 1, pp. 51-56.Russia, YakutiaDeposit - Sytykanskaya
DS201503-0170
2015
Yuryeva, O.P.Rakhmanova, M.I., Nadolinny, V.A., Yuryeva, O.P., Pokhilenko, N.P., Logvinova, A.M.Pecularities of nitrogen impurity aggregation in diamonds from the Sytykanskaya pipe, Yakutia.European Journal of Mineralogy, Vol. 27, pp. 51-56.Russia, YakutiaDeposit - Sytykanskaya
DS201509-0440
2015
Yuryeva, O.P.Yuryeva, O.P., Rakhmanova, M.I., Nadolinny, V.A., Zedgenizov, D.A., Shatsky, V.S., Kagi, H., Komarovskikh, A.Yu.The characteristic photoluminescence and EPR features of superdeep diamonds ( Sao Luis, Brazil).Physics and Chemistry of Minerals, In press available 16p.South America, Brazil, Mato GrossoDeposit - Juina area

Abstract: Photoluminescence (PL) spectroscopy and electron paramagnetic resonance (EPR) were used for the first time to characterize properties of superdeep diamonds from the São-Luis alluvial deposits (Brazil). The infrared measurements showed the low nitrogen content (>50 of 87 diamonds from this locality were nitrogen free and belonged to type IIa) and simultaneously the extremely high level of nitrogen aggregation (pure type IaB being predominant), which indicates that diamonds under study might have formed under high pressure and temperature conditions. In most cases, PL features excited at various wavelengths (313, 473, and 532 nm) were indicative of different growth and post-growth processes during which PL centers could be formed via interaction between vacancies and nitrogen atoms. The overall presence of the 490.7 nm, H3, and H4 centers in the luminescence spectra attests to strong plastic deformations in these diamonds. The neutral vacancy known as the GR1 center has probably occurred in a number of crystals due to radiation damage in the post-growth period. The 558.5 nm PL center is found to be one of the most common defects in type IIa samples which is accompanied by the EPR center with g-factor of 2.00285. The 536 and 576 nm vibronic systems totally dominated the PL spectra of superdeep diamonds, while none of "normal" diamonds from the Mir pipe (Yakutia) with similar nitrogen characteristics showed the latter three PL centers.
DS201511-1892
2015
Yuryeva, O.P.Yuryeva, O.P., Rakhmanova, M.I., Nadolinny, V.A., Zedgenizov, D.A., Shatsky, V.S., Kagi, H., Komarovskikh, A.Yu.The characteristic photoluminescence and EPR features of superdeep diamonds ( Sao-Luis, Brazil).Physics and chemistry of Minerals, Vol. 42, 9, pp. 707-722.South America, BrazilSao-Luis alluvials

Abstract: Photoluminescence (PL) spectroscopy and electron paramagnetic resonance (EPR) were used for the first time to characterize properties of superdeep diamonds from the São-Luis alluvial deposits (Brazil). The infrared measurements showed the low nitrogen content (>50 of 87 diamonds from this locality were nitrogen free and belonged to type IIa) and simultaneously the extremely high level of nitrogen aggregation (pure type IaB being predominant), which indicates that diamonds under study might have formed under high pressure and temperature conditions. In most cases, PL features excited at various wavelengths (313, 473, and 532 nm) were indicative of different growth and post-growth processes during which PL centers could be formed via interaction between vacancies and nitrogen atoms. The overall presence of the 490.7 nm, H3, and H4 centers in the luminescence spectra attests to strong plastic deformations in these diamonds. The neutral vacancy known as the GR1 center has probably occurred in a number of crystals due to radiation damage in the post-growth period. The 558.5 nm PL center is found to be one of the most common defects in type IIa samples which is accompanied by the EPR center with g-factor of 2.00285. The 536 and 576 nm vibronic systems totally dominated the PL spectra of superdeep diamonds, while none of "normal" diamonds from the Mir pipe (Yakutia) with similar nitrogen characteristics showed the latter three PL centers.
DS201612-2351
2016
Yuryeva, O.P.Zedgenizov, D.A., Kalinina, V.V., Reutsky, V.N., Yuryeva, O.P., Rakhmanova, M.I.Regular cuboid diamonds from placers on the northeastern Siberian platform.Lithos, Vol. 265, pp. 125-137.Russia, SiberiaDiamond morphology

Abstract: Alluvial placers of the northeastern Siberian Platform are characterized by a specific diamond population: regular cuboids, forming a continuous color series from yellowish-green to yellow and dark orange. This is the first comprehensive study of a large number of cuboid diamonds focusing on their morphology, N content and aggregation state, photoluminescence, C isotopic composition and inclusions. The cuboids are cubic (i.e. nearly flat faced) to subrounded crystals; most of them are resorbed. The cathodolominescence images and the birefringence patterns show that many cuboid diamonds record deformation. The cuboid diamonds are characterized by unusual FTIR spectra with the presence of C- (single nitrogen atom) and A- (pair of neighbour nitrogen atoms) centers, and two centers of unknown origin, termed X and Y. The presence of single substitutional nitrogen defects (C centers) in all cuboid diamonds testifies either storage in the mantle at relatively cool conditions or formation just prior to eruption of their host kimberlites. The studied diamonds are also characterized by the presence of specific set of luminescence centers: N3, H3, S1, NVo and NV?, some of which are suggested to have formed during deformation subsequent to diamond growth. The cuboid diamonds show a wide range of carbon isotope compositions from mantle-like values towards strongly 13C depleted compositions (? 6.1 to ? 20.2‰ ?13C). Combined with the finding of an eclogitic sulfide inclusion, the light carbon isotope compositions link the formation of the studied cuboids to deeply subducted basic protoliths, i.e. former oceanic crust.
DS201706-1111
2017
Yuryeva, O.P.Yuryeva, O.P., Rakhmanova, M.I., Zedgenizov, D.A.Nature of type 1aB diamonds from the Mir kimberlite pipe (Yakutia): evidence from spectroscopic observation.Physics and Chemistry of Minerals, in press available 13p.Russia, Yakutiadeposit - Mir
DS201711-2536
2017
Yuryeva, O.P.Yuryeva, O.P., Rakhmanova, M.I., Zedgenizov, D.A.Nature of type IaB diamonds from the Mir kimberlite pipe ( Yakutia): evidence from spectroscopic observation.Physics and Chemistry of Minerals, Vol. 44, 9, pp. 655-667.Russia, Yakutiadeposit - Mir

Abstract: In this study, the specific features of structural defects of type IaB diamonds from the Mir kimberlite pipe (Yakutian diamondiferous province) have been characterized using FTIR and photoluminescence spectroscopy. Mineral inclusions in these diamonds [olivine (Ol), orthopyroxene (OPx), chromite (Chr), sulphide (Sf)] correspond to associations of peridotite rocks at the base of the lithosphere. Nitrogen content in type IaB diamonds shows significant variations, suggesting different growth media and/or several growth stages. A specific feature of these diamonds is the absence or very small amount of platelets, which may be related to annealing during their long-term residence at the temperatures of the base of the lithosphere. All studied diamonds show the presence of hydrogen defects that are active in IR spectra with an intense line at 3107 cm?1, and additional weaker lines at 3085 and 3237 cm?1, which correlated with high nitrogen content. Type IaB diamonds are also characterized by the presence of nitrogen-nickel luminescence centres S2, S3 and 523.2 nm. This feature distinguishes them from superdeep diamonds with extreme nitrogen aggregation states, which clearly attest to different growth conditions and crystallization media of type IaB diamonds from the Mir kimberlite pipe.
DS201909-2086
2019
Yuryeva, O.P.Shatsky, V.S., Nadolinny, V.A., Yuryeva, O.P., Rakhamanova, M.I., Komarovskikh, A.Yu.Features of the impurity composition of diamonds from placers of the northeastern Siberian craton.Doklady Earth Sciences, Vol. 486, 2, pp. 644-646.Russia, Siberiadiamond morphology

Abstract: Diamond crystals from the Istok (25 crystals) and Mayat (49 crystals) placers were studied using the EPR, IR, and luminescence methods. The total content of impurity nitrogen in forms of A, B, and C (P1) centers ranges from 50 to 1200 ppm. According to the EPR spectroscopy, the presence of nitrogen C (P1), N3V and nitrogen-titanium OK1, N3, NU1 impurity centers was established in the investigated crystals. For 18 crystals from the Istok placer, the N3 nitrogen-titanium center was observed in the EPR spectra, but in the luminescence spectra there was no 440.3 nm system, which was previously attributed to the manifestation of the N3 defect. It is more likely that the nitrogen-titanium N3 EPR center corresponds to the electron-vibrational system 635.7 nm, which is observed in the luminescence spectra of these crystals. Crystals from the Istok placer contain the OK1, N3, and NU1 centers, but luminescence attributed to the oxygen-containing centers is absent in the region of 610-670 nm. For the Mayat placer crystals, the reverse situation was observed. The luminescence ascribed to the oxygen-containing centers was detected for 17 crystals, but there were no OK1, N3, and NU1 centers according to the EPR and luminescence. This result contradicts the arguments of a number of authors about the oxygen nature of these defects. For 5 crystals from the Mayat placer, the nickel impurity was registered. This indicates the presence of ultrabasic paragenesis diamond crystals in this placer.
DS202002-0211
2020
Yuryeva, O.P.Nadolly, V.A., Shatsky, V.S., Yuryeva, O.P., Rakhmanova, M.I., Komarovskikh, A.Yu., Kalinin, A.A., Palyanov, Yu.N.Formation features of N3V centers in diamonds from the Kholomolokh placer in the Northeast Siberian craton.Physics and Chemistry of Minerals, Vol. 47, 4, 7p. PdfRussia, Siberiadeposit - Khololmolokh

Abstract: In recent years, despite significant progress in the development of new methods for the synthesis of diamond crystals and in their post-growth treatment, many questions remain unclear about the conditions for the formation and degradation of aggregate impurity nitrogen forms. Meanwhile, they are very important for understanding (evaluating) the origin, age, and post-growth conditions of natural diamonds. In the present work, an attempt was made to analyze the causes of the formation of high concentrations of N3V centers in natural IaB-type diamonds from the Kholomolokh placer (the Northeast Siberian craton). The possibility of decay of B centers during the plastic deformation of diamonds is analyzed and experiments on the high-temperature annealing of diamonds containing B centers are reported. The formation of N3V centers during the destruction of the B centers at high-pressure annealing of crystals has been established by experiment. It is assumed that, in the post-growth period, diamond crystals were exposed to tectono-thermal stages of raising the superplumes of the Earth's crust of the Siberian craton.
DS202005-0774
2020
Yuryeva, O.P.Yuryeva, O.P., Rakhmanova, M.I., Zedgenizov, D.A., Kalinina, V.V.Spectroscopic evidence of the origin of brown and pink diamonds family from Internatsionalnaya kimberlite pipe ( Siberian craton).Physics and Chemistry of Minerals, Vol. 47, 20 doi.org/10/1007/ s00269-020-01088-5 19p. PdfRussiadeposit - International

Abstract: New spectroscopic data were obtained to distinguish the specific features of brown and pink diamonds from Internatsionalnaya kimberlite pipe (Siberian craton). It is shown that pink and brown samples differ markedly in the content and degree of aggregation of nitrogen defects. Pink diamonds generally have higher nitrogen content and a lower aggregation state compared to brown samples, which often show significant variations in nitrogen content and aggregation state between different growth zones. The 491 and 576 nm luminescent centres, which are signs of deformed brown diamonds, are absent or of low intensity in pink diamonds implying that high nitrogen content predominantly in A form in the pink diamonds had stiffened the diamonds against natural plastic deformation. The GR1 centre, formed by a neutrally charged vacancy, was observed only in pink diamonds, which may be due to their formation and storage in the mantle at lower-temperature conditions. Mineral inclusions indicate peridotitic and eclogitic paragenesis for studied brown and pink diamonds, respectively. It is suggested that brown diamonds have been formed in a primitive mantle at higher temperatures and/or stored there much longer.
DS202111-1778
2021
Yuryeva, O.P.Nadolinny, V.A., Komarovskikh, A.Yu., Rakhmanova, M.I.,Yuryeva, O.P., Shatsky, V.S., Palyanov, Yu.N. Guskova, M.I.New data on the N1 nitrogen paramagnetic center in brownish type IaAB diamonds from Mir pipe.Diamond and Related Materials, Vol. 120, 108638 6p. PdfRussiadeposit - Mir

Abstract: In this work, two brownish crystals from the Mir pipe attributed to type IaAB have been examined by a complex of spectroscopic methods: electron paramagnetic resonance, infrared, and photoluminescence spectroscopies. A combination of features such as brownish color, optical system 490.7 nm, and paramagnetic centers W7 and 490.7 points out to plastic deformation of the crystals. The W7 is known to be formed as a result of destruction of A-aggregates during plastic deformation while part of the N3V centrers can be formed due to the disruption of the B-aggregates. The narrow-line EPR spectra from the nitrogen-related N3V centers and the P1 centers indicate that the crystals were annealed after plastic deformation. Another feature of the crystals studied is the observation of the well-known paramagnetic N1 center with only two magnetically inequivalent positions (i.e. with two magnetically inequivalent directions of the C1-N1 fragments) instead of the previously reported four. Possible transformation pathways of the W7 center (N1-C1-C2-N2+) into the N1 center (N1-C-N2+) during the post-deformation annealing are considered.
DS202205-0713
2022
Yuryeva, O.P.Rakhmanova, M.I., Komarovskikh, A.Y., Ragozin, A.L., Yuryeva, O.P., Nadolinny, V.A.Sprectroscopic features of electron-irradiated diamond crystals from the Mir kimberlite pipe, Yakutia.Diamond and Related Materials, Vol. 126, 109057Russiadeposit - Mir

Abstract: The behavior of characteristic centers in diamond crystals from the Mir pipe (Yakutia) was investigated upon electron irradiation. A series of diamond crystals of different types was chosen for experiments based on the nitrogen content and aggregation parameters. In electron-irradiated diamonds of the IaAB type, a new characteristic photoluminescence system was found with a zero-phonon line (ZPL) at 615 nm together with phonon replicas of 41 and 90 meV. The phonons' energies pointed to multiphonon interactions with a quasilocal vibration of a vacancy. According to our data, the nitrogen-related defect responsible for this phenomenon contains a vacancy and may be accompanied by some other impurity. Conversely, in an almost nitrogen-free crystal, a specific system with the ZPL at 558 nm was noted. The center in question is known to be vacancy-related and was formed in type IIa crystals from the Mir pipe not only by electron irradiation but also by high-pressure high-temperature annealing when vacancies were released as a result of motion or annihilation of dislocations. Regardless of the nitrogen impurity, specific systems with the ZPL at 454, 491, and 492 nm were registered in the irradiated diamond crystals from the Mir pipe. To examine the generated defects, the irradiated diamond crystals were subjected to low-temperature annealing at ?600 °C. Although the 454 and 491 nm systems persisted, the annealing of the 492 nm system along with well-known 523.6, 489.0, and 503.4 nm (3H) centers indicated the interstitial-vacancy nature of the defect.
DS1985-0021
1985
Yusa, K.Aoki, K.I., Yoshida, T., Yusa, K., Nakamura, Y.Petrology and Geochemistry of the Nyamuragira Volcano, ZaireJournal of VOLCANOLOGY, Vol. 25, No. 1-2, JUNE PP. 1-28.Central Africa, ZairePetrology
DS1970-0835
1973
Yusa, Y.Suma, K., Yusa, Y., Kishada, N.Petrology of Peridotite Nodules from the Ndonyro Clnchoro Sanburn District Central Kenya.1st International Kimberlite Conference, EXTENDED ABSTRACT VOLUME, PP. 301-304.GlobalPetrology
DS1995-2112
1995
Yusfin, B.Yusfin, B.The Bamcredit bank: financing mining projects in SiberiaWorld Mining Congress, Institute International Research held May, 4pRussia, Siberia, AmurEconomics -investment
DS1992-0025
1992
Yu-ShenAnderson, D.L., Tanimoto, T., Zhang, Yu-ShenPlate tectonics and hotspots: the third dimensionScience, Vol. 256, June 19, pp. 1645-1651MantleHot spots, Shear velocity
DS1992-1089
1992
Yu-Shen ZhangMorin, P.J., Yuen, D.A., Tanimoto, T., Yu-Shen ZhangVisualizing interactively the three dimensional structure of the earth'smantleEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 197MantleGeophysics, Structure
DS1992-1729
1992
Yu-Shen ZhangYu-Shen Zhang, Tanimoto, T.Ridges, hot spots and their interaction as observed in seismic velocitymapsNature, Vol. 355, January 2, pp. 45-49GlobalHot spots, Geophysics
DS1993-1805
1993
Yu-Shen ZhangYu-Shen Zhang, Tanimoto, T.High resolution global upper mantle structure and plate tectonicsJournal of Geophysical Research, Vol. 98, No. B6, June 10, pp. 9793-9823.MantleTomography, Geophysics -seismics
DS1993-1806
1993
Yu-Shen Zhiang. Tanimoto, T.Yu-Shen Zhiang. Tanimoto, T.High resolution global upper mantle structure and plate tectonicsJournal of Geophysical Research, Vol. 98, No. B6, June 10, pp. 9793-9823MantleTectonics, Structure, Tomography, seismic
DS200712-0492
2006
Yusheng, W.Jianxin, Z., Jingsui, Y., Fabcong, M.,Yusheng, W., Huimin, Li., Cailai, W.U Pb isotopic studies of eclogites and their host gneisses in the Xitishan area of the North Qaidam mountains, western China: new evidence HP-UHP belt.Journal of Asian Earth Sciences, Vol. 28, 2-3, Nov. 15, pp. 143-150.ChinaUHP, Eclogites
DS1992-0026
1992
Yu-Sheng ZhangAnderson, D.L., Yu-Sheng Zhang, Tanimoto, T.Plume heads, continental lithosphere, flood basalts and tomographyGeological Society Special Publication Magmatism and the causes of the, No. 68, pp. 99-124GlobalMantle, Hotspots
DS200912-0174
2009
Yushkin, N.A.P.A.Divaev, F.A.K.A., Shumilova, T.A.G.A., Yushkin, N.A.P.A., Makeev, B.A.A.A.First occurrence of diamonds in shonkinite porphyrys of the northern Tamdytau ( Central Kyzylkumy, western Uzbekistan).Doklady Earth Sciences, Vol. 425, 2, pp. 216-218.Russia, UzbekistanDiamond - shonkinite
DS1970-0456
1971
Yushkin, N.P.Yushkin, N.P., Fishman, A.M.On the Origin of the Surfaces of Rounded Pyrope Grains From diamond Bearing Kimberlites.Izv. Vuzov. Geol. I Razv., No. 3.RussiaBlank
DS1994-0012
1994
Yusupov, I.S.Afanasev, V.P., Sobolev, N.V., Kirillov, E.A., Yusupov, I.S.Relative abrasive stability of pyrope and pyroilmenite -indicator minerals of kimberlite.(Russian)Doklady Academy of Sciences Nauk, Vol. 337, No. 3, July pp. 359-362.Russia, SiberiaMineralogy, Indicator minerals
DS1984-0560
1984
Yusupov, R.G.Novgordova, M.I., Yusupov, R.G., et al.Cubic silicon carbide intergrowth with graphite and diamonds inMumiyo.(Russian)Doklady Academy of Sciences Akademy Nauk SSSR, (Russian), Vol. 277, No.5 pp. 1222-1227RussiaMineralogy, Diamond
DS1993-1807
1993
Yusupov, R.G.Yusupov, R.G.Diamonds of orogenic regions, geochemical features and parageneticaccessories.(Russian)Geochemistry International (Geokhimiya), (Russian), No. 6, June pp. 852-861.RussiaGeochemistry, Diamond morphology
DS1994-1973
1994
Yusupov, R.G.Yusupov, R.G.Geochemical features and accessory mineral parageneses for orogenic regiondiamonds:Central, South Tien Shan.Geochemistry International, Vol. 31, No. 1, pp. 83-92.ChinaDiamond morphology, Geochemistry
DS1996-1582
1996
Yusupov, R.G.Yusupov, R.G., Polykovskiy, V.S., Mustafin, S.K.Native metals and nonmetals, carbides and silicides and the gas composition of their fluid inclusions...Doklady Academy of Sciences, Vol. 336, pp. 96-100.China, Tien ShanDiamond, Granulite ecologite
DS200912-0845
2009
Yusupov, R.G.Yusupov, R.G., Stanley, C.J., Welch, M.D., Spratt, J., Cressey, G., Rusmsey, M.S., Seltmann, R., IgamberdievMavlyanovite, Mn5813: a new mineral species from a lamproite diatreme, Chatkal Ridge, Uzbekistan.Mineralogical Magazine, Vol. 73, 1, Feb. pp. 43-50.RussiaLamproite mineralogy
DS200712-1101
2007
Yusupov, T.S.Sobolev.Urakaev, F.K., Shevchenko, V.S., Logvinoa, A.M., Madyukov, I.A., Petrushin, E.I., Yusupov,T.S.Sobolev.Mechano chemical processing of low grade diamond into nanocomposite materials.Doklady Earth Sciences, Vol. 415, 5, pp. 755-758.RussiaMining - mineral processing
DS2003-1538
2003
Yutkina, E.V.Yutkina, E.V., Kononova, V.A., Kozar, N.A., Lnyazkov, A.P.Sr Nd and geochemical compositions of kimberlite from the eastern Azov region, theirDoklady Earth Sciences, Vol. 391, 5, pp. 751-54.RussiaGeochemistry, geochronology
DS200412-2192
2004
Yutkina, E.V.Yutkina, E.V., Kononova, V.A., Bogatikov, O.A., Knyazkov, A.P., Kozar, N.A., Ovchinnikova, G.V., Levsky, L.K.Kimberlites of eastern Priazove ( Ukraine) and geochemical characteristics of their sources.Petrology, Vol. 12, 2, pp. 134-148.Europe, UkraineDevonian age, Arkangelsk, Terskii Bereg, Novolaspinakay
DS200412-2193
2003
Yutkina, E.V.Yutkina, E.V., Kononova, V.A., Kozar, N.A., Lnyazkov, A.P.Sr Nd and geochemical compositions of kimberlite from the eastern Azov region, their age and nature of the lithospheric source.Doklady Earth Sciences, Vol. 391, 5, pp. 751-54.RussiaGeochemistry, geochronology
DS200512-1227
2005
Yutkina, E.V.Yutkina, E.V., Kononova, V.A., Tsymbal, S.N., Levskii, L.K., Kiryanov, N.N.Isotopic geochemical specialization of mantle source of kimberlites from the Kirovograd complex, Ukrainian shield.Doklady Earth Sciences, Vol. 402, 4, pp. 551-555.Russia, UkraineGeochronology
DS201601-0025
2015
Yutkina, E.V.Kargin, A.V., Babarina, I.I., Bogatikov, O.A., Yutkina, E.V., Kondrashov, I.A.Paleproterozoic Kimozero kimberlite ( Karelian Craton): geological setting and geochemical typing.Doklady Earth Sciences, Vol. 465, 1, pp. 1135-1138.RussiaDeposit - Kimozero

Abstract: Geological and structural mapping of Paleoproterozoic Kimozero kimberlite with account for lithological facies and geochemical specialization provides evidence for the multiphase structure of the kimberlite pipe, which underwent fragmentation as a result of shear–faulting deformations. Two geochemical types of kimberlite (magnesium and carbonate) are distinguished.
DS201811-2554
2018
Yutkina, E.V.Bogatikov, O.A., Dokuchaev, A.Ya., Kargin, E.V., Yutkina, E.V., Kondrashov, I.A.Paleoproterozic kimberlites of the Lake Kimozero area, Karelian craton: ore mineralization in kimberlites and fault zones.Doklady Earth Sciences, Vol. 482, 1, pp. 1130-1133.Russiadeposit - Lake Kimozero

Abstract: Syngenetic and epigenetic ore mineralization was studied in Paleoproterozoic metakimberlites in the area of Kimozero Lake. In the Kimozero structure, redeposited ore mineralization is constrained to fracture and shear zones and consists of Fe-vaesite, Fe-Co-polydymite, millerite, Ni-pyrrhotite, pentlandite, chalcopyrite, Zn-bearing copper, galena, and Ni-pyrite. The composition of this mineralization is analogous to that of syngenetic mineralization in pyroclastic and coherent kimberlite, and its likely source was the kimberlite itself.
DS1993-1255
1993
Yuzhu LiPopov, V.S., Yuzhu LiThe basanites of the Nuishan volcanic cone, east China, as a result of the partial melting of primitive lherzolites.Geochemistry International, Vol. 30, No. 4, pp. 45-53.ChinaBasanite
DS202010-1850
2020
Yuzmukhametov, R.N.Kiseeva, E.S., Yuzmukhametov, R.N.Women at the dawn of diamond discovery in Siberia or how two women discovered the Siberian diamond province. Popugaeva and SarsadskhihBurek, C.V., Higgs, B. eds Celebrating 100 years of female fellowship of the Geological Society: Discovering forgotten histories. Geological Society of London Special Publ. 506, in press, 13p. PdfRussia, Siberiahistory

Abstract: Exploration for diamonds in the Soviet Union started in the 1940s, however it was not until the beginning of 1950s that the government acknowledged a strong need for locally mined diamonds. In this article, based on publications from Russian literature, we recount a story of two female geologists, Larisa Popugaeva and Natalia Sarsadskhih. Natalia was the head of the mineralogical laboratory who implemented a new methodology to search for mineral indicators of primary diamond deposits. Larisa was a young geologist who joined Natalia's team in 1953. The work of these women led to the discovery in 1954 of the first diamond deposit in the country - a kimberlite pipe "Zarnitsa". In 1954 Natalia was unable to go into the field, therefore the discovery was made by Larisa. Credit for this discovery, however, was claimed by the higher officials from the Amakinskaya expedition, one of the largest diamond exploration organisations in the country. Multiple efforts to restore justice did not succeed, with Larisa only being awarded the title of the "Discoverer" in 1970, and Natalia not until 1990. This article provides a description of Larisa's and Natalia's life up until the discovery of Zarnitsa, and a few significant events after.
DS1991-1916
1991
Yvon, J.Yvon, J., Marion, P., Michot, L., Villieras, F., Wagner, F.E.Development of mineralogy applications in mineral processingEur. Journal of Mineral, Vol. 3, No. 4, pp. 667-676GlobalMineral processing, overview
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
 
 

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