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A synthesis of iron deposits in the eastern Tianshan,NW China

Geoscience Frontiers 2020年第4期11卷 1271-1287页

作者： Jiahao Zheng Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

The northern Xinjiang region is one of the most significant iron metallogenic provinces in *** deposits are found mainly within three regions:the Altay,western Tianshan,and eastern Tianshan orogenic *** studies have elaborated on the genesis of Fe deposits in the Altay orogenic belt and western ***,the geological characteristics and mineralization history of iron deposits in the eastern Tianshan are still poorly *** this paper I describe the geological characteristics of iron deposits in the eastern Tianshan,and discuss their genetic types as well as metallogenic-tectonic settings,Iron deposits are preferentially distributed in central and southern parts of the eastern *** known iron deposits in the eastern Tianshan show characteristics of magmatic Fe-Ti-V(e.g.,Weiya and Niumaoquan),sedimentary-metamorphic type(e.g.,Tianhu),and iron skarn(e.g.,Hongyuntan).In addition to the abovementioned iron deposits,many iron deposits in the eastern Tianshan are hosted in submarine volcanic rocks with well-developed skarn mineral *** geological characteristics and magnetite compositions suggest that they may belong to distal *** zircon U-Pb analyses suggest that the Fe-Ti oxide ores from Niumaoquan and Weiya deposits were formed at 307.7±1.3 Ma and 242.7±1.9 Ma,*** with available isotopic age data,the timing of Fe mineralization in the eastern Tianshan can be divided into four broad intervals:Early Ordovician-Early Silurian(476-438 Ma),Carboniferous(335-303 Ma),Early Permian(295-282 Ma),and Triassic(ca.243 Ma).Each of these episodes corresponds to a period of subduction,post-collision,and intraplate tectonics during the Paleozoic and Mesozoic time.

关键词： Iron deposits Geological characteristics Ore-forming ages Genetic types Eastern Tianshan

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U–Pb LA-ICP-MS geochronology of polygenetic zircons from Beshta and Kamenistaya intrusions(the Greater Caucasus)

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Acta Geochimica 2022年第6期41卷 1019-1029页

作者： David Shengelia Leonid Shumlyanskyy Giorgi Chichinadze Tamara Tsutsunava Giorgi Beridze Irakli Javakhishvili Al.Janelidze institute of Geology of Iv.Javakhishvili Tbilisi State University TbilisiGeorgia School of Earth and Planetary Sciences Curtin UniversityPerthAustralia M.P.Semenenko institute of Geochemistry Mineralogy and Ore FormationKyivUkraine

The Beshta-Kamenistaya intrusions are located in the Main Range structural zone of the Greater *** are composed of tonalitic gneisses that genetically resemble granites of the tholeiitic series of the ophiolitic *** Beshta-Kamenistaya orthogneisses and associated rocks of the nappes differ markedly from those of the Main Range *** of them were overthrust to the Main Range zone during the Bretonian *** age of their protolith and the metamorphism are still not *** the zircon U-Pb LA-ICP-MS dating two age populations of zircons have been distinguished in the rocks of the Beshta-Kamenistaya *** age of the main population of zircons from orthogneisses is 426-300 *** age groups can be distinguished in this *** main group yielded a Concordia age of386.9±1.4 *** are also smaller peaks at 409-405,375-373,and 351 *** oldest ages(426-395 Ma)were detected in the core parts of the complex *** assume that the crystallization of the parental for orthogneisses rocks(tonalities)took place at 410-395 Ma,whereas the Concordia age of 386.9±1.4 Ma and a peak at 375-373 Ma correspond to the metamorphic *** whole metamorphic cycle,including progressive and regressive stages,occurred between 395 and 370 ***,dated in the Beshta-Kamenistaya intrusion at350 Ma and younger,correspond to the Late Variscan *** dated 3102-2769 Ma represent xenocrysts captured by the melts during their formation from the ancient rocks in the crystalline basement.

关键词： The Greater Caucasus Magmatism Metamorphism Orthogneisses U–Pb zircon dating

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Imaging disturbance zones ahead of a tunnel by elastic full-waveform inversion:Adjoint gradient based inversion *** space reduction using a level-set method

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Underground Space 2018年第1期3卷 21-33页

作者： Andre Lamert Luan T.Nguyen Wolfgang Friederich Tamara Nestorovic Seismology Institute of GeologyMineralogy and GeophysicsRuhr-Uniersity BochumGermany Reservoir Engineering and Rock Physics International Geothermal CenterBochuon University of Applied SciencesGermany Mechanics of Adaptive Systems Institute of Computational EngineeringRudhr-Umiversity BochumGermany

We present and compare twoﬂexible and effective methodologies to predict disturbance zones ahead of underground tunnels by using elastic full-waveform *** methodology uses a linearized,iterative approach based on misﬁt gradients computed with the adjoint method while the other uses iterative,gradient-free unscented Kalmanﬁltering in conjunction with a level-set *** the former does not involve a priori assumptions on the distribution of elastic properties ahead of the tunnel,the latter intro-duces a massive reduction in the number of explicit model parameters to be inverted for by focusing on the geometric form of potential disturbances and their average elastic *** imaging methodologies are validated through successful reconstructions of simple *** an application,we consider an elastic multiple disturbance *** using identical synthetic time-domain seismo-grams as test data,we obtain satisfactory,albeit different,reconstruction results from the two inversion *** computa-tional costs of both approaches are of the same order of magnitude,with the gradient-based approach showing a slight *** model parameter space reduction approach compensates for this by additionally providing a posteriori estimates of model parameter uncertainty.

关键词： Tunnel seismics Full waveform inversion Seismic waves Level-set method Adjoint method Kalman filter

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Composition of the Diamond Indicator Minerals on the Mitchell Chart――Criteria of CLIPPIR Diamonds in Kimberlites and Conditions of their Mantle Crystallization

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Acta Geologica Sinica(English Edition) 2021年第S1期95卷 121-124页

作者： Vladimir N.ZINCHENKO Alexandr S.IVANOV Igor V.ASHCHEPKOV CATOCA Mining Society СatocaAngola ALROSA Ltd. MirnyRussia V.S.Sobolev institute of Geology and mineralogy SB RAS NovosibirskRussia

In the last decade,researchers have been particularly interested in IIa CLIPPIR type diamonds,which differ in composition and physical characteristics from diamonds of peridotite related"P"and eclogite related"E"***(Moore,2009)sought them as mantle kimberlite related megacrysts,but light C isotopy and chemical features needs special explanation.

关键词： CLIPPIR diamonds kimberlite mantle pyrope clinopiroxene chromite ilmenite

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Geochemical signal of seasonality in annually laminated organic- carbonate sediments in Shira lake(Khakasia)

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 12-13页

作者： Ivan KALUGIN Andrey DARIN Denis ROGOZIN Gennady TRET'YAKOV Sobolev institute of Geology and mineralogy Siberian Branch Russian Academy of Sciences institute of Biophysics Siberian Branch Russian Academy of Sciences

1 Introduction The most valuable for the task of climate reconstruction are the time series with an annual resolution,which allows to reveal natural periodicity and pass to the search for mechanisms of regional and global climatic *** sediments of lakes are one of the best climate archives in addition to tree ring series,ice cores etc.

关键词： saline lake Shira seasonal sedimentation physicochemical modeling carbonates Ca/Sr ratio

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Melt inclusions in minerals of schorlomite-rich veins of the Hatrurim Basin,Israel:composition and homogenization temperatures

Melt inclusions in minerals of schorlomite-rich veins of the...

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First Meeting Asia Current Research on Fluid Inclusion

作者： V.V.Sharygin Ye.Vapnik E.V.Sokol V.S.Kamenetsky R.Shagam institute of mineralogy and petrography UIGGM SD RAS Novosibirsk Russia Department of Geological and Environmental Sciences Ben-Gurion University of the Negev Beer-Sheva Israel institute of mineralogy and petrography UIGGM SD RAS Novosibirsk Russia Centre for Ore Deposit Research University of Tasmania Hobart Tasmania 7001 Australia Department of Geological and Environmental Sciences Ben-Gurion University of the Negev Beer-Sheva Israel

Introduction The Hatrurim Basin is the largest occurrence of combustion metamorphism (CM) complex in Israel (Gross, 1977;Burg et al., 1991). The rocks of this CM complex ("Mottled Zone" or Hatrurim Formation) are localized around the Dead Sea Transform on the territory of Israel, Jordan and Syria. K-Ar and and 40Ar/39Ar dating indicates at least two major CM events: in Plio-Pleistocene (4.0-1.5 Ma) and in Miocene (16 Ma) (Gur et al., 1995). This CM complex was formed by wide-scale low-pressure and high-temperature (sanidinite facies) pyrogenic transformation of the Cretaceous protolith of carbonate and silicate-carbonate composition which is comparable to analogous sediments of the Middle East oil-and-gas province.

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Boron isotopic variations in tourmaline from metacarbonates and associated calc-silicate rocks from the Bohemian Massif: Constraints on boron recycling in the Variscan orogen

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Geoscience Frontiers 2021年第1期12卷 219-230页

作者： Lukas Krmcek Milan Novak Robert B.Trumbull Jan Cempirek Stanislav Houzar Department of Geological Sciences Faculty of ScienceMasaryk UniversityKotlarska 2CZ-61137BrnoCzech Republic institute of Geology of the Czech Academy of Sciences Rozvojova 269CZ-16502Prague 6Czech Republic Brno University of Technology Faculty of Civil EngineeringAdMaS CentreVeve■rí95CZ-60200BrnoCzech Republic GFZ German Research Centre for Geosciences TelegrafenbergD-14473PotsdamGermany Department of mineralogy and petrography Moravian MuseumZelnyTrh 6CZ-67401BrnoCzech Republic

Various metacarbonate and associated calc-silicate rocks form minor but genetically significant components of the lithological units in the Bohemian Massif of the Variscan orogen in Central *** rocks vary in terms of their lithostratigraphy,chemical composition and mineral assemblage(dolomite/calcite ratio,silicate abundance).Tourmaline is present in five paragenetic settings within the metacarbonate and calc-silicate ***Ⅰcomprises individual,euhedral,prismatic grains and grain aggregates in a carbonate-dominant(calcite±dolomite)matrix poor in ***Ⅱis characterized by euhedral to subhedral grains and coarse-to fine-grained aggregates in silicate-rich layers/nests within metacarbonate bodies whereas typeⅢoccurs as prismatic grains and aggregates at the contact zones between carbonate and associated silicate host ***Ⅳis in veins crosscutting metacarbonate bodies,and typeⅣtourmaline occurs at the exocontacts of elbaite-subtype granitic *** from the different settings shows distinctive compositional *** for typeⅠare Mg-rich compositions,with fluor-uvite>dravite>>*** from typeⅡsilicate-rich layers/nests are highly variable,corresponding to oxy-schorl,magnesio-foitite,Al-rich dravite and *** for typeⅢtourmalines are Ca,Ti-bearing oxy-dravite *** typeⅣveins feature dravite and fluor-uvite tourmaline compositions whereas typeⅤtourmaline is Li,F-rich *** is the only Bbearing phase in paragenetic typesⅠ-Ⅳ,where it is characterised by two principal ranges of B-isotope composition(δ^11B=-13‰to-9‰and-18‰to-14‰).These ranges correspond to regionally different units of the Moldanubian ***,the Svratka Unit(Moldanubian Zone s.l.)contains only isotopically lighter tourmaline(δ^11B=-18‰to-14‰),whereas metacarbonates in the Poli?ka unit(Teplá-Barrandian Zone)and Olesnice unit(Moravicum of the Moravo-Silesian Zone)has exclusively isotopically heav

关键词： Boron isotopes Tourmaline Metacarbonates Moldanubicum Variscan orogeny

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Interaction of polyhydroxy fullerenes with ferrihydrite：adsorption and aggregation

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Journal of Environmental Sciences 2018年第2期30卷 1-9页

作者： Jing Liu Runliang Zhu Tianyuan Xu Mingwang Laipan Yanping Zhu Qing Zhou Jianxi Zhu Hongping He Key Laboratory of mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development Guangzhou 510640 China University of Chinese Academy of Sciences Beijing 100049 China

The rapid development of nanoscience and nanotechnology, with thousands types of nanomaterials being produced, will lead to various environmental impacts. Thus,understanding the behaviors and fate of these nanomaterials is essential. This study focused on the interaction between polyhydroxy fullerenes（PHF） and ferrihydrite（Fh）, a widespread iron（oxyhydr）oxide nanomineral and geosorbent. Our results showed that PHF were effectively adsorbed by Fh. The adsorption isotherm fitted the D-R model well, with an adsorption capacity of 67.1 mg/g. The adsorption mean free energy of 10.72 k J/mol suggested that PHF were chemisorbed on Fh. An increase in the solution p H and a decrease of the Fh surface zeta potential were observed after the adsorption of PHF on Fh; moreover, increasing initial solution p H led to a reduction of adsorption. The Fourier transform infrared spectra detected a red shift of C–O stretching from 1075 to 1062 cm-1 and a decrease of Fe–O bending, implying the interaction between PHF oxygenic functional groups and Fh surface hydroxyls. On the other hand, PHF affected the aggregation and reactivity of Fh by changing its surface physicochemical properties. Aggregation of PHF and Fh with individual particle sizes increasing from 2 nm to larger than 5 nm was measured by atomic force microscopy. The uniform distribution of C and Fe suggested that the aggregates of Fh were possibly bridged by PHF. Our results indicated that the interaction between PHF and Fh could evidently influence the migration of PHF, as well as the aggregation and reactivity of Fh.

关键词： Nanoparticles Polyhydroxy fullerenes Ferrihydrite Adsorption Aggregation

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Low Temperature Synthesis of Zeolites of the Faujasite Family (FAU-EMT) Using Industrial Mineral Waste (FR) from Silane Production

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Journal of Materials Science and Chemical Engineering 2017年第11期5卷 1-13页

作者： Valeriy Petrov Josef-Christian Buhl institute of mineralogy Leibniz University Hannover Hannover Germany

Zeolite formation was investigated under low temperature conditions between 40°C - 25°C under insertion of a Si-rich filtration residue (FR) from waste water cleaning of the silane production. Syntheses were performed under open system conditions without stirring. The application of templates was excluded but gel formation was optimized by addition of citric acid. Beside a minimal consumption of process energy during synthesis under very low temperatures even FR was inserted without an expansive pre-treatment like calcination. Disordered intergrowths of FAU-EMT intermediates were obtained in each case, even at a temperature of only 25°C. The reaction products always occurred in two sequences, one at the bottom and another at the top of the reaction bin. A better crystallinity was detected for the latter products and the Si/Al ratio of these FAU-EMT members was close to 1.0 like in zeolite LSX. In contrast chemical analyses revealed an enrichment of Ca- and Mg- impurities from FR in the bottom products.

关键词： FAU-EMT Zeolites Disordered Intergrowths Industrial Waste 25°C Synthesis

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褶皱带橄榄岩-榴辉岩杂岩和稳定地块含金刚石岩筒的成因特征(英文)

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地学前缘 2007年第2期14卷 109-128页

作者： A.A. Marakushev A.V. Bobrov N.A. Paneyakh V.K. Garanin Department of Petrology Geological Faculty M.V. Lomonosov Moscow State University Leninskie Gory institute of Geology of Ore Deposits Mineralogy Petrography and Geochemistry Russian Academy of Sciences Staromonetnyi per. 35

金刚石母岩可以是榴辉岩、辉石岩、橄榄岩等多种岩石,它们与金刚石都是在地幔深处形成的,并上侵最终固结于地壳中。母岩中的金刚石等矿物在地壳中又发生准稳定生长。地壳中金伯利岩和钾镁煌斑岩岩浆作用对金刚石母岩侵入体进行改造,使... 详细信息

金刚石母岩可以是榴辉岩、辉石岩、橄榄岩等多种岩石,它们与金刚石都是在地幔深处形成的,并上侵最终固结于地壳中。母岩中的金刚石等矿物在地壳中又发生准稳定生长。地壳中金伯利岩和钾镁煌斑岩岩浆作用对金刚石母岩侵入体进行改造,使原生金刚石发生破碎、溶解、再生长等一系列变化,并形成巨晶、劣质金刚石和黑金刚石等新类型,这些现象不是在金刚石母岩形成之初发生的。

关键词：褶皱带稳定地块金刚石远景层状侵入体金伯利岩筒原生岩浆

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