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Acta Geologica Sinica(English Edition) 2024年第3期98卷 641-656页

作者： WANG Qiuyu CHEN Shouming ZHANG Hongrui LI Saisai SinoProbe Laboratory Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Guangxi Key Laboratory of Hidden Metallic ore Deposit Exploration GuilinGuangxi 541004China

High-silica granitoids record the formation and evolution of the continental crust.A new intrusive complex has been recognized among silicic volcanic rocks of the Weixi arc,Southwest *** intrusions consist of granites,granitic porphyries,and *** U-Pb age data indicate that the Weixi granitoids formed at 248-240 Ma and were coeval with silicic volcanic rocks of the Weixi *** Weixi granitoids are enriched in Rb,Th,and U,depleted in Ba,Sr,Nb,Ta,and Ti,and have high light/heavy rare earth element ratios and slightly negative Eu *** Weixi granitoids have negative ε_(Nd)(t)values(-9.8 to-7.8)and negative zircon ε_(Hf)(t)values(-12.02 to-5.11).The geochemical and isotopic features suggest the Weixi granitoids were derived by partial melting of ancient crustal *** Weixi granitoids and silicic volcanic rocks were derived from the same magma by crystal accumulation and melt extraction,respectively,and they record the formation of a continental arc in the central Sanjiang orogenic belt.

关键词： granitoids geochemistry crystal accumulation continental crust Sanjiang orogen

Origin of water in the Moon

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National Science Review 2024年第6期11卷 10-12页

作者： Hejiu Hui Ziyan Han Kang Shuai State Key Laboratory of Mineral deposits Research & Lunar and Planetary Science institute School of Earth Sciences and Engineering Nanjing University CAS Center for Excellence in Comparative Planetology CAS Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics

It has been well known since the Apollo era that the Moon is relatively depleted in volatiles as a result of the Moonformation impact and the subsequent planetary differentiation. The lunar interior was believed to have been extremely dry [1]. The discovery of indigenous water (a collective term for H-bearing species OH, H2O, etc.) in various lunar materials [2–5] has driven a paradigm shift in our knowledge of water in the Moon, from a dry to a wet Moon.

关键词： LUNAR HYDROGEN TERRESTRIAL INTERIOR

The Origin of Mesozoic A-type Granitoids,Fujian Province,Southeast China:Insights from Geochronology,Mineralogy and Geochemistry

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 630-640页

作者： XIE Qifeng DONG Yunpeng CAI Yuanfeng ZHAI Mingguo XIAO Aifang ZHANG Hong Zijin School of geology and Mining Fuzhou UniversityFuzhou 350108China State Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China State Key Laboratory for Mineral deposits Research Nanjing UniversityNanjing 210023China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still *** results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 Ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.The Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock *** samples are enriched in HFSEs(i.e.,Ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of *** the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_(N),10000×Al/Ga,Rb/Nb and Nb/Ta etc.,they were proved to be alkaline A-type *** the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization *** values of ε_(Hf)(t)and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement *** comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate.

关键词： A-type granitoid geochronology extension subduction Mesozoic Southeast China

A New Discovery of Mineralization as Subseafloor Hydrothermal Replacement in the Duddar Super-Large SEDEX Lead-Zinc Deposit in Pakistan

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Journal of Earth Science 2024年第3期35卷 1075-1078页

作者： Huishan Zhang Yucai Song Jianing Sun Jun Hong Yasir Shaheen Khalil Yanguang Li Haidi Zhang Zhihua Wang MNR Key Laboratory for the Study of Focused Magmatism and Giant ore deposits Xi’an Center of Geological SurveyChina Geological SurveyXi’an 710054China institute of geology Chinese Academy of Geological SciencesBeijing 100037China Chengdu Center of Geological Survey China Geological SurveyChengdu 610081China China Huaye Group Co. LtdBeijing 100037China Geological Survey of Pakistan Islamabad 44000Pakistan

0 INTRODUCTION Sedimentary exhalative(SEDEX)lead-zinc deposit was traditionally considered as a result of submarine hydrothermal exhalation,including exhalative plume and brine pool models(Izanloo et al.,2022;Spinks et al.,2021;Maghfouri et al.,2020;Sangster,2020,2018;Huang et al.,2019;Rajabi et al.,2015;Goodfellow and Lydon,2007;Large et al.,2005,2001;Peng et al.,2000;Goodfellow et al.,1993;Figures 1a,1b).However,recognition of mineralization as subseafloor hydrothermal replacement in a few SEDEX deposits has challenged the traditional consideration(Magnall et al.,2023,2021,2020a,b;Hayward et al.,2021;Figure 1c).Researchers come to believe that subseafloor replacement rather than submarine exhalation is a dominant process for SEDEX mineralization,but this needs to be examined through more case studies.

关键词： submarine mineralization seafloor

What Controls the Distribution of ore Veins in Quartz Vein-type Tungsten deposits: Constrains from Fan-shaped Mineralization in SE China

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Journal of Earth Science 2024年

作者： Gui-Cong Fang Deng-Hong Wang Fu-Qiang Yang Zhan-Xu Ni Chang-Shuai Huang Ping Wang Meng Feng Zuo-Hai Feng Guangxi Key Laboratory of Hidden Metallic ore deposits Exploration， College of Earth Science， Guilin University of Technology Collaborative Innovation Center for Exploration of Nonferrous Metal deposits and Efficient Utilization of Resources By the Province and Ministry，Guilin University of Technology institute of Mineral Resources， Chinese Academy of Geological Sciences Guangxi Zhuang Autonomous Region institute of Geophysical Exploration Geological Team No.271 of Guangxi Zhuang Autonomous Region China Nonferrous Metal Guilin Research institute of geology for Mineral Resources Co.， Ltd Guangdong Geologic Survey institute

Quartz vein-type tungsten deposits are a common W deposit type. Their ore vein distribution was previously considered to be controlled by regional horizontal tectonic stress. In this paper， 14 tungsten deposits with fan-shaped mineralization in SE China are summarized， and the relations between their ore veins and granite and the ore-forming structural stress field are analyzed. These deposits have a post-magmatic hydrothermal genesis and involve the formation of two sets of veins with similar strike and opposite dips at the top of the ore-causative granite bodies， forming a vertical fan-shaped profile. Their ore veins were coeval with the underlying granite bodies， and generally extend along the long axis of the granite. In such fan-shaped ore formation， the stress is highly focused at the top of the granite and gradually weakens outward. The maximum principal stress (σ1) is perpendicular to the granite contact surface， and radiates outward from the pluton. Meanwhile， the minimum principal stress (σ3) forms an arc-shaped band parallel to the contact surface. Our findings， together with published numerical modeling indicate that the emplacement dynamics of granitic magma (rather than regional horizontal tectonic stress) are essential controls on the distribution of ore veins in quartz vein-type tungsten deposits.

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Mineralogy and geochemistry of trachytic rocks from the Lichi Volcanics, Eastern Himalaya: insights into the Kerguelen mantle plume activity in the Eastern Himalayan Region

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Acta Geochimica 2024年第1期43卷 180-197页

作者： Pallabi Basumatary Deepshikha Borah Hiredya Chauhan Tribujjal Prakash Bibhuti Gogoi Department of geology Cotton UniversityGuwahatiAssam 781001India Wadia institute of Himalayan geology DehradunUttarakhand 248001India

The Lichi volcanics are a suite of mafic-intermediate-felsic rocks and are considered coeval with the Abor volcanics(~132 Ma) of the Siang window in the Eastern Himalaya. Here, we present the first report of trachytic rocks from the Lichi volcanics, which are exposed in the Ranga valley, along the Kimin-Yazali road section in the Eastern Himalayan Region, Northeast India. The trachytes occur in close association with sandstones of the Gondwana Group of rocks and are characterised based on field, petrographical, and geochemical *** fine-grained trachytes are composed of alkali feldspar, biotite, plagioclase, sodic-amphibole, apatite, illmenite, and titanite. The REE profiles of the evolved trachytic rocks(higher SiO_(2)content) display fractionated trends. The fractionation of accessory mineral phases, like apatite and titanite, was possibly responsible for the strongly fractionated REE patterns of the evolved *** trachytic rocks demonstrate high apatite saturation temperatures of 988 ± 14 ℃(1σ, n = 8). The Aluminium Saturation Index(< 1.1) and binary discrimination diagrams of these peralkaline trachytes define their affinity with A-type granitoids. Elemental ratios like Y/Nb, Nb/U,and Ce/Pb signify that the Lichi trachytes are differentiated products of mantle-derived ocean island basalts. Trace elemental discrimination diagrams Th/Yb versus Nb/Yb, Y versus Nb, and Y + Nb versus Rb reflect a within-plate tectonic regime for the trachytes. From the results presented in this work, we infer that the development of rifting events during the breakup of eastern Gondwana due to the onset of Kerguelen plume activity further led to underplating of basic magma in lower crustal levels. These parental basaltic magmas underwent fractionation processes forming differentiated trachyandesites and *** into consideration the similarities recorded between the Lichi volcanics and Abor volcanics, this study supports the idea that Kerguelen plume ac

关键词： Peralkaline trachytes Trachyandesites A-type granitoids Apatite saturation temperature Abor volcanics Eastern Gondwana

Newly identified Au-Ag-Bi-Te mineralization in the Aydindere skarn Fe and Cu deposit， Giresun， NE Turkey: implications of gold mineralization during retrograde skarn evolution

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Journal of Earth Science 2024年

作者： Ahmet Sasmaz Vitaliy Sukach Serhiy Bondarenko Hryhorii Aleksiienko Hengameh Erfanian Kaseb Bilge Sasmaz Sergiy Kurylo Oleksandr Hrinchenko Volodymyr Somka Panagiotis Voudouris Department of geology， Firat University Faculty of geology and Geoenvironment， National and Kapodistrian University of Athens Mineralogy and ore Formation of National Academy of Science， M.P.Semenenko institute of Geochemistry 3. Department of Petroleum Engineering， Eqbal Lahoori institute of Higher Education

This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit， within the Pontides Tectonic Unit， northeastern Turkey. The mineralization is developed in the skarn zone at the contact between Upper Cretaceous andesite-pyroclastic rocks and a Paleocene-Eocene I-type granitoid. The principal ore minerals of the Aydindere Fe-Cu deposit are oxides (magnetite)， sulfides (pyrite-chalcopyrite-galena-sphalerite)， tellurides/sulfotellurides (tetradymite， hessite)， sulfosalts (wittichenite， emplectite， aikinite) and native gold-electrum. Skarn minerals include anhydrous phases (garnet) formed in a prograde stage and hydrous phases (amphibole， epidote， chlorite)， which were formed in a retrograde stage in association with quartz， adularia， apatite and late calcite. Sulfides， tellurides and sulfosalts are introduced during the retrograde stage. The Au-Ag-Bi-Te mineralization was detected for the first time within the western ore body of the Aydindere deposit， and occurs in calcite-bearing sulfide bodies that cut magnetite-garnet-amphibole-epidote skarns with magnetite ores of different grade， including massive magnetite. Chlorite geothermometry indicates formation of the Au-Ag-Bi-Te mineralization at temperatures between 300 and 250 °C， during the retrograde skarn evolution. Assuming the temperature is ～275°C， logfS2= -10.5 to -13， logfO2= -37 to -33， and logfTe2values range from approximately -12 to -8.5 were estimated. The available mineralogical and geological data (presences of magnetite， oxidized-type tellurides/sulfotellurides， and andraditic garnets， and absence of pyrrhotite and arsenopyrite) suggest that Aydindere is an oxidized Au-bearing skarn deposit. The discovery of Au-Ag-Bi-Te mineralization at Aydindere increases its productivity and requires more detailed exploration in the deposit for precious (Au， Ag) and critical (Bi， Te) metals.

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Spatial continuous modeling of early Cenozoic carbon cycle and climate

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National Science Review 2024年第4期11卷 30-32页

作者： Yonggang Liu Jian Zhang Haoyue Zuo Zhilin He Jiaqi Guo Qifan Lin Haonan Yu Jiawenjing Lan Jing Han Zhihong Song Zihan Yin Liang Zhao Yongyun Hu Zhengtang Guo Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Key Laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences

The partial pressure of atmospheric CO2（pCO2） is determined by the carbon cycle that involves climate, biogeochemistry, and plate tectonics. In this cycle,atmospheric CO2is converted into organic carbon and carbonates by biological activities and silicate weathering, and buried as sediments. The sediments on the ocean floor are subducted into the Earth’s interior, and subsequently converted back into CO2and outgassed into the atmosphere.

关键词： ATMOSPHERIC CO2

Age and petrogenesis of the newly discovered Early Permian granite in the Kumtor gold field， Kyrgyz Tien-Shan

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Journal of Earth Science 2024年

作者： Kyiazbek Asilbekov Rustam Orozbaev Etienne Skrzypek Christoph Hauzenberger Elena Ivleva Daniela Gallhofer Jian-Feng Gao Nikolay Pak Anatoliy Shevkunov Anatoliy Bashkirov Aizat Zhaanbaeva institute of geology， National Academy of Sciences of the Kyrgyz Republic institute of Earth Sciences， University of Graz State Key Laboratory of ore Deposit Geochemistry， institute of Geochemistry， Chinese Academy of Sciences Kumtor Gold Company CJSC

Permian intrusions are widespread in the Middle and Southern Tien Shan， with fewer occurrences in the Northern Tien-Shan. Notably， many of these intrusions are spatially associated with a variety of ore deposits， indicating a significant link between magmatic activity and mineralization processes in these areas. We studied granite samples recently recovered from drilling in the Kumtor gold field to evaluate their potential relationships with gold mineralization. We report major and trace element geochemistry， zircon U-Pb age and Hf isotope data for this so-called Kumtor granite. The Kumtor granite is metaluminous to peraluminous and belongs to the high-K and calc-alkaline series with I-type geochemical characteristics. The relatively high K2O and Na2O concentrations and low high field strength elements （HFSE） and heavy rare earth elements （HREE）， the presence of biotite within these I-type granites， together with their low zircon saturation temperatures （731–779 °C）， suggest that they were likely derived from a hydrous source formed by dehydration melting of mica-bearing， medium- to high-K metabasaltic rocks. Our zircon U-Pb dating results indicate that the Kumtor granite intruded at 293 ± 1.7 Ma， which is consistent with the age range of other Middle Tien-Shan granitoids. The zircon Hf isotopic composition is εHf（t）= –7.56 to –5.05， indicating an ancient （1.39 to 1.52 Ga） crustal origin. Petrographical， geochemical and geochronological data indicate that the Kumtor granite is similar to leuco-granites of the Terekty complex. Our results indicate that the Kumtor granite was emplaced in the early Permian in a post-collision setting and may have temporal and genetic relationships with gold mineralization.

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Global paleobiogeography of Albian—Cenomanian(mid-Cretaceous)marine ostracods

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Journal of Palaeogeography 2024年第2期13卷 212-236页

作者： Bernardo Vázquez-García Jorge Villegas-Martín Gerson Fauth Leonardo Borghi Aristóteles De Moraes Rios Netto Post-Graduate Program in geology Unisinos UniversitySao LeopoldoRSBrazil Technological institute of Paleoceanography and Climate Change-Itt Oceaneon Unisinos UniversitySao LeopoldoRSBrazil Laboratory of Sedimentary geology(Lagesed) Department of GeologyInstitute of GeosciencesUFRJ-Federal Universityof Riode JaneiroBrazil Labmicro Department of GeologyInstitute of GeosciencesUFRJ-Federal University of Rio de JaneiroBrazil

Despite their potential for providing important information for paleobiogeography,studies using ostracod assemblages compiled from global datasets have been scarce so *** this study,the paleogeographic implications of the relationship between different ostracod assemblages are analyzed and discussed for the Albian and *** compiled an ostracod dataset at the genus level,with 168 genera for the Albian and 174 for the Cenomanian,to which different multivariate statistical methods of grouping were *** affinity between different ostracod assemblages from different regions allowed for the delineation of 30 operational geographic units(OGUs)for the Albian,and 32 OGUs for the Cenomanian,grouped in three paleobiogeographic units(PBUs;Megatethys,Persia,and Austral)and one sub-unit(PBSU;Maghreb associated to the Megatethys).The Maghreb PBSU showed minor changes between the Albian and *** relationship among the OGUs grouped in each PBU is related to different factors,such as eustatic sea level events,similar climatic zones,and marine current circulation patterns.A relationship was observed between the Gabon and Nigeria OGUs with the Persia PBU,which suggests a direct east—west connection between them during the *** affinity observed in the Austral PBU between the South American,South African,and Australian regions during the Albian can be explained by their relative geographic isolation due to the Walvis Ridge *** eventual flooding of this barrier led to the relationship observed between the SE Brazilian and Bolivian regions with the Austral ***,the data also suggested that the separation of the Indian subcontinent from the Austral PBU took place during the Cenomanian.

关键词： Operational geographic units Paleobiogeographic units Albian Cenomanian Marine ostracods