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Genesis of the Jianbeigou Gold Deposit on the Southern Margin of the North China Craton: Insights from Fluid Inclusions, H-O-S Isotopes, and Pyrite in situ Trace Element Analyses
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作者 LI Fengchun ZENG Qingdong +5 位作者 ZHU Rixiang CHU Shaoxiong XIE Wei YU Bing WU Jinjian LI Xinghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期969-991,共23页
The Jianbeigou gold deposit is a typical lode gold deposit in the Qinling metallogenic belt, located on the southern margin of the North China Craton. Three stages of the hydrothermal process can be distinguished, inc... The Jianbeigou gold deposit is a typical lode gold deposit in the Qinling metallogenic belt, located on the southern margin of the North China Craton. Three stages of the hydrothermal process can be distinguished, including the quartz ± pyrite, quartz-polymetallic sulfide, and quartz-carbonate ± pyrite stages. From the early to late stages, the homogenization temperatures of primary fluid inclusions are 281–362°C, 227–331°C, and 149–261°C, respectively. The corresponding salinities estimated for these fluids are 3.9–9.9 wt%, 0.4–9.4 wt%, and 0.7–7.2 wt% Na Cl equiv. Combined with laser Raman spectroscopy data, the ore-forming fluid belongs to a H_(2)O-CO_(2)-Na Cl ± CH_4 system with medium–low temperature and salinity. The δ~(18)Ofluid and δD values for the quartz veins are-1.0‰ to 6.0‰ and-105‰ to-84‰, respectively, which indicates that the ore-forming fluid is of mixed source, mainly derived from magma, with a contribution from meteoric water. Pyrite has been identified into three generations based on mineral paragenetic sequencing, including Py1, Py2, and Py3. The pyrites have δ~(34)S sulfur isotopic compositions from three stages between 3.7‰ and 8.4‰, indicating that sulfur mainly originated from magma. Te, Bi, Sb, and Cu contents in pyrite were all high and showed a strong correlation with Au concentrations. Native gold and the Au-Ag-Bi telluride minerals were formed concurrently, and the As concentration was low and decoupled from the Au content. Therefore, Te, Bi, Sb and other low-melting point chalcophile elements play an important role for gold mineralization in arsenic-deficient ore-forming fluid. Combined with the geological setting, evolution of pyrite, and ore-fluids geochemistry, we propose that the Jianbeigou deposit can be classified as a magmatic–hydrothermal lode gold deposit. Gold mineralization on the southern margin of the North China Craton is related to Early Cretaceous magmatism and formed in an extensional setting. 展开更多
关键词 ore genesis h-o-s isotopes fluid inclusions in-situ trace element Jianbeigou gold deposit
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Metallogenesis and hydrothermal evolution of the Tonggou Cu deposit in the Eastern Tianshan:Evidence from fluid inclusions,H-O-S isotopes,and Re-Os geochronology 被引量:1
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作者 Xue-bing Zhang Chuan Chen +2 位作者 Fang Xia Ling-ling Gao Hong-yan Quan 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第6期2301-2312,共12页
The Tonggou Cu polymetallic deposit in the Bogda Orogenic Belt,Eastern Tianshan shows evidence for three stages of hydrothermal mineralization:early pyrite veins(Stage 1),polymetallic sulfide±epidote-quartz(Stage... The Tonggou Cu polymetallic deposit in the Bogda Orogenic Belt,Eastern Tianshan shows evidence for three stages of hydrothermal mineralization:early pyrite veins(Stage 1),polymetallic sulfide±epidote-quartz(Stage 2),and late-stage pyrite-calcite veins(Stage 3).Fluid inclusion petrography and microthermometry analyses indicate that the liquid-rich aqueous inclusions(L),vapour-rich aqueous inclusions(V),and NaCl daughter mineral-bearing three phase inclusions(S)formed during the main stage of mineralization,and that the ore fluids represent high-temperature and high-salinity H20-NaCl hydrothermal fluids that underwent boiling.Stable isotope(H,O)data indicate that the ore fluids of the Tonggou deposit were originally derived from magmatic water in Stage 2 and subsequently mixed with local meteoric water during Stage 3.Sulphur isotope compositions(6.7‰to 10.9‰)are consistent with theδ^34 S values of pyrite from the Qijiaojing Formation sandstone,indicating the primary source of the sulphur ore.Furthermore,chalcopyrite grains separated from the chalcopyrite-rich ore samples yield an isochron age of 303±12 Ma(MSWD=1.2).These results indicate that the Tonggou deposit is a transition between high-sulfidation and porphyry deposits which formed in the Late Carboniferous.It also suggests an increased likelihood for the occurrence of Cu(Au,Mo)in the Bogda Orogenic Belt,especially at locations where the Cu-Zn deposits are thicker;further deep drilling and exploration are encouraged in these areas. 展开更多
关键词 Fluid inclusion Stable isotope Chalcopyrite RE-OS GEOCHRONOLOGY Tonggou DEPOSIT The Eastern TIANSHAN
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Origin of ore-forming fluids in Qinggouzi stibnite deposit,NE China:Constraints from fluid inclusions and H-O-S isotopes
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作者 BAKHT Shahzad SUN Fengyue +4 位作者 WANG Linlin XU Chenghan YE Lina ZHU Xinran FAN Xingzhu 《Global Geology》 2021年第2期80-88,共9页
The Qinggouzi stibnite deposit is located in Huashan Town,Jilin Province,in the northeastern margin of North China Craton(NCC).It is controlled by fault structures,hosted within structurally controlled felsic dykes,pr... The Qinggouzi stibnite deposit is located in Huashan Town,Jilin Province,in the northeastern margin of North China Craton(NCC).It is controlled by fault structures,hosted within structurally controlled felsic dykes,predominantly surrounded by phyllite,schist and quartzite.This study presents the results of fluid inclusions studies,intending to determine the source of the fluid responsible for ore-formation,hence exploring its metallogenesis.The aqueous biphase inclusions are identified in the stibnite-bearing quartz veins of the deposit.Moreover,aqueous biphase inclusions are further classified into(1)biphase liquid-rich inclusions(1 a)and(2)biphase gas-rich inclusions(1 b)depending upon liquid to gas ratio trapped within the fluid inclusions.Homogenization temperatures for(1 a)and(1 b)range between 114.8℃to 422℃and 128.3℃to 267.5℃,respectively.1 a and 1 b have salinities of 0.18%to 16.14%NaCleqv and 1.22%to 12.88%NaCleqv,and density range from 0.43 to 1.02 g/cm^(3) and 0.81 to 0.98 g/cm^(3),respectively.Sulfur isotopic analysis indicatesδ34SV-CDT from 4.4×10-3 to 6.5×10^(-3),with an average of 5.2×10^(-3),whereas H isotopes values onδDV-SMOW standard are-100.8×10^(-3) and-107.5×10^(-3),while O isotopes data onδ18OV-SMOW standard range between 20.1×10^(-3) and 20.4×10-3.Fluid inclusions study,combining with sulfur and H-O isotopic data reveal that the ore-forming fluids originated from deep source and were subsequently contaminated by meteoric water.Hydrostatic pressure calculation shows that the minimum and maximum pressures are 11.65 and 42.33 MPa,and relevant depths of deposit are estimated to be 1.16 and 4.23 km.Finally,we inferred that Qinggouzi stibnite deposit is a medium-low temperature,low salinity hydrothermal deposit,which is formed by deep source and later contaminated by meteoric water,and is classified as epizonal deposit in terms of orogenic series. 展开更多
关键词 fluid inclusions S isotopes H-O isotopes METALLOGENESIS Qinggouzi stibnite deposit orogenic deposits
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Fluid inclusion and H-O-S-Pb isotope systematics of the Chayong Cu-polymetallic deposit,Sanjiang Metallogenic Belt,Qinghai Province,China
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作者 Jian Wang Hao Wang +3 位作者 Fengyue Sun Fei Wang Xiangwen Li Hongju Yue 《Acta Geochimica》 EI CAS CSCD 2024年第6期1153-1168,共16页
The Chayong Cu-polymetallic deposit is a recently discovered Cu-polymetallic deposit hosted in the Sanjiang Metallogenic Belt within the Tibetan Plateau of China to the northeast of the North Qiangtang terrane.The ore... The Chayong Cu-polymetallic deposit is a recently discovered Cu-polymetallic deposit hosted in the Sanjiang Metallogenic Belt within the Tibetan Plateau of China to the northeast of the North Qiangtang terrane.The ore body occurs in siltstone and is controlled by a northwest-trending fault structure.According to the associations,assemblages,and cutting relationships between ore veins,the hydrothermal mineralization period can be divided into three mineralization stages:(1)a molybdenite mineralization stage,(2)a Cu-polymetallic sulfide stage,and(3)a quartzcarbonate stage.Two types of fluid inclusions(FIs),namely,liquid and vapor-rich inclusions,are present in quartz as so ciated with sulfide minerals.Early-stage FIs are both iquid and vapor-rich,homogenized at temperatures ranging from 364.1 to 384.2℃,and have salinities ranging from0.70%to 9.60%NaCl equivalent(eqv).The middle-stage FIs are also both liquid-and vapor-rich,homogenized at temperatures ranging from 272.4 to 355.6℃,and have salinities ranging from 0.53%-17.10%NaCl eqv.The late-stage FIs are liquid,homogenized at temperatures ranging from 209.4to 255.3℃,and have salinities ranging from 0.35%-6.87%NaCl eqv.The samples from the deposit haveδ^(34)S values of-21.8‰to-19.2‰and-5.5‰to-6.0‰,suggesting that sulfur was derived from the host sediments and magmatic fluids,respectively.The metallic minerals within the deposit have^(206)Pb/^(204)Pb,^(207)Pb/^(204)Pb,and^(208)Pb/^(204)Pb values of 18.439-18.458,15.656-15.679,and 38.772-38.863,respectively,suggesting that the metals were derived from the upper crust and orogenic belts.The samples from the deposit haveδ^(18)O_(W)values of 2.99‰-7.99‰andδD_(W) values ranging from-84.4‰to-73.9‰,indicating that the pre-forming fluids were magmatic and mixed with minor amounts of meteoric water.The ore-forming fluid of the Chayong copper polymetallic deposit was a high-temperature,medium-to low-salinity H_(2)O-NaCl-CH_(4)-N_(2)±CO_(2)fluid system.The early high-temperature magmatic fluid,due to boiling,decreased in temperature,and via the mixing of meteoric water,gradually evolved towards the later-stage medium-to low-temperature and low-salinity fluid,causing nolybdenite mineralization and forming copper polymetallic sulfide veins and quartz carbonate veins. 展开更多
关键词 Fluid inclusions S isotope Pb isotope H-O isotope Chayong Cu-polymetallic deposit Sanjiang Metallogenic Belt YUSHU Qinghai
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Metallogenic Age and Ore-forming Material Sources of the Dahongshan Fe-Cu Deposit,Yunnan Province:Insights from Molybdenite Re-Os Dating and H-O-S-Pb Isotopes
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作者 YE Zifeng YANG Guangshu +2 位作者 YU Wenxiu CHEN Aibing JIA Fuju 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第6期1698-1718,共21页
The Dahongshan Fe-Cu(-Au)deposit is a superlarge deposit in the Kangdian metallogenic belt,southwestern China,comprising approximately 458 Mt of Fe ores(40%Fe)and 1.35 Mt Cu.Two main types of Fe-Cu(-Au)mineralization ... The Dahongshan Fe-Cu(-Au)deposit is a superlarge deposit in the Kangdian metallogenic belt,southwestern China,comprising approximately 458 Mt of Fe ores(40%Fe)and 1.35 Mt Cu.Two main types of Fe-Cu(-Au)mineralization are present in the Dahongshan deposit:(1)early submarine volcanic exhalation and sedimentary mineralization characterized by strata-bound fine-grained magnetite and banded Fe-Cu sulfide(pyrite and chalcopyrite)hosted in the Na-rich metavolcanic rocks;(2)late hydrothermal(-vein)type mineralization characterized by Fe-Cu sulfide veins in the hosted strata or massive coarse-grained magnetite orebodies controlled by faults.While previous studies have focused primarily on the early submarine volcanic and sedimentary mineralization of the deposit,data related to late hydrothermal mineralization is lacking.In order to establish the metallogenic age and ore-forming material source of the late hydrothermal(-vein)type mineralization,this paper reports the Re-Os dating of molybdenite from the late hydrothermal vein Fe-Cu orebody and H,O,S,and Pb isotopic compositions of the hydrothermal quartz-sulfide veins.The primary aim of this study was to establish the metallogenic age and ore-forming material source of the hydrothermal type orebody.Results show that the molybdenite separated from quartz-sulfide veins has a Re-Os isochron age of 831±11 Ma,indicating that the Dahongshan Fe-Cu deposit experienced hydrothermal superimposed mineralization in Neoproterozoic.The molybdenite has a Re concentration of 99.7-382.4 ppm,indicating that the Re of the hydrothermal vein ores were primarily derived from the mantle.The δ^(34)S values of sulfides from the hydrothermal ores are 2‰-8‰ showing multi-peak tower distribution,suggesting that S in the ore-forming period was primarily derived from magma and partially from calcareous sedimentary rock.Furthermore,the abundance of radioactive Pb increased significantly from ore-bearing strata to layered and hydrothermal vein ores,which may be related to the later hydrothermal transformation.The composition of H and O isotopes within the hydrothermal quartz indicates that the ore-forming fluid is a mixture of magmatic water and a small quantity of water.These results further indicate that the late hydrothermal orebodies were formed by the Neoproterozoic magmatic hydrothermal event,which might be related to the breakup of the Rodinia supercontinent.Mantle derived magmatic hydrothermal fluid extracted ore-forming materials from the metavolcanic rocks of Dahongshan Group and formed the hydrothermal(-vein)type Fe-Cu orebodies by filling and metasomatism. 展开更多
关键词 stable isotopes Re-Os dating ore-forming material Dahongshan Fe-Cu deposit Kangdian region
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Genesis of the Huoshenmiao Mo deposit in the Luanchuan ore district, China: Constraints from geochronology, ?uid inclusion, and H-O-Sisotopes 被引量:3
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作者 Sai Wang Bing Li +4 位作者 Xingkang Zhang Peng Wang Weiwei Chao Huishou Ye Yongqiang Yang 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第1期331-349,共19页
The Huoshenmiao δeposit is Mo skarn δeposit, located in the western part of the Luanchuan ore δistrict.Mineralization process can be δivided into a skarn and a quartz-sulfide episodes with six stages: prograde(I),... The Huoshenmiao δeposit is Mo skarn δeposit, located in the western part of the Luanchuan ore δistrict.Mineralization process can be δivided into a skarn and a quartz-sulfide episodes with six stages: prograde(I), retrograde(II), quartz-K-feldspar(III), quartz-molybdenite(IV), quartz-pyrite(V), and quartzcalcite(VI). A combined study of geochronology, fluid inclusion(FI), and stable isotopes was conducted to constrain the mineralization age, source of ore materials, as well as the origin and evolution of the ore-forming fluids. Molybdenite Ree Os δating indicates that the δeposit was formed in the Late Jurassic(~145 Ma). The δ^(34)S values of sulfides range from 3.0‰ to 7.1‰, implying that the ore materials in the δeposit are magmatic in origin. Three types and six subtypes of FIs are δistinguished, namely, aqueous two-phase(W_1-and W_2-type), δaughter mineral-bearing multiphase(S_1-and S_2-type), and CO_2-bearing three-phase(C_1-and C_2-type). In stages I and II, the W_1-type FIs δisplay homogenization temperatures(Th) from 496°C to >600°C, with salinities of 14.9-18.3 wt.% NaCl eqv. The FIs in stages III, IV and early stage V composed of coeval S-, C-and W-types, respectively homogenize at similar Th, suggesting the occurrence of boiling. The W1-type FIs in late stage V and stage VI, yield Th of 102-406°C and salinities of 0-4.7 wt.% NaCl eqv. The δD_(H_2O)and δ^(18) O(H_2O)values of the ore-forming fluids in quartz-sulfide episode vary from-112‰ to-76‰, and 11.0‰ to 1.0‰, respectively. All these above observations reveal that the early ore-forming fluids are magmatic in origin, and characterized by high temperature and moderate to high salinity, and gradually evolve to low temperature, low salinity meteoric water. The Huoshenmiao Mo δeposit is associated with the magmatism event induced by the protracted subduction of the Izanagi plate beneath the eastern China continent. The δecrease in temperature, salinity and f(O_2), as well as change of p H δue to boiling and fluid-rock interaction, are the main factors controlling Mo δeposition. 展开更多
关键词 Molybdenite Ree Os age Fluid inclusion h-o-s isotopes Huoshenmiao Mo deposit Luanchuan ore district
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Rising utilization of stable isotopes in tree rings for climate change and forest ecology 被引量:1
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作者 Ru Huang Chenxi Xu +3 位作者 Jussi Grießinger Xiaoyu Feng Haifeng Zhu Achim Bräuning 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期103-116,共14页
Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive re... Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive review.This study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope research.Overall,1475 publications were selected from the Web of Science Core Collection for 1974-2023.The findings are that:(1)numbers of annual publications and citations increased since 1974.From 1974 to 1980,there were around two relevant publications per year.However,from 2020 to 2022,this rose sharply to 109 publications per year.Likewise,average article citations were less than four per year before 1990,but were around four per article per year after 2000;(2)the major subjects using tree ring stable isotopes include forestry,geosciences,and environmental sciences,contributing to 42.5%of the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of Sciences(423),the Swiss Federal Institute for Forest,Snow and Landscape Research(227),and the University of Arizona(204).These achievements result from strong collaborations;(4)review papers,for example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly focus on climatology and ecology,with atmospheric CO_(2) one of the most popular topics.Since 2010,precipitation and drought have received increasing attention.Based on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are summarized.This study serves as an important attempt to understand the progress on the use of stable isotopes in tree rings,providing scientific guid-ance for young researchers in this field. 展开更多
关键词 Tree rings Stable isotopes Web of Science BIBLIOMETRIC
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胶东大尹格庄金矿成矿流体时空演化及矿床成因:来自流体包裹体、成矿元素和H-O-S-Pb同位素证据 被引量:2
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作者 严子清 石文杰 +6 位作者 张鹏涛 王勇军 邵玉宝 黄鑫 宋宇 谭俊 王治华 《地质科技通报》 CAS CSCD 北大核心 2024年第2期156-174,共19页
大尹格庄金矿位于招平成矿带中段,是胶东地区典型的构造蚀变岩型金矿床,储量达到超大型规模,但关于该矿床的成因类型尚存在较大争议。在详细野外地质调查的基础上开展了该矿床成因和成矿流体纵向变化特征研究。流体包裹体研究表明,成矿... 大尹格庄金矿位于招平成矿带中段,是胶东地区典型的构造蚀变岩型金矿床,储量达到超大型规模,但关于该矿床的成因类型尚存在较大争议。在详细野外地质调查的基础上开展了该矿床成因和成矿流体纵向变化特征研究。流体包裹体研究表明,成矿流体为中温、低盐度、中低密度的H_(2)O-CO_(2)-NaCl±CH_(4)体系。从成矿早期到晚期各阶段(Ⅰ~Ⅳ阶段)均一温度和盐度逐渐降低,密度逐渐增加。氢氧同位素组成显示成矿流体早期以岩浆水为主,后期有大气降水的混入,主成矿阶段可能存在流体沸腾作用;黄铁矿硫铅同位素组成表明成矿物质来源于深源壳幔混合岩浆。成矿过程和背景总体与胶东其他金矿床类似,形成于克拉通破坏环境。浅部与深部流体和物质组成的对比研究表明,在垂向纵深范围内成矿流体性质、金银成矿强度和金成色稳定一致,金沉淀具有宽泛而稳定的环境,指示大尹格庄金矿床深部仍然具有很大的成矿潜力和找矿空间。 展开更多
关键词 流体包裹体 h-o-s-Pb同位素 金成色 矿床成因 深部找矿 成矿流体 大尹格庄
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Geochronology and Ore Genesis of the Niujuan-Yingfang Pb-Zn-Ag Deposit in Fengning,Northern North China Craton:Constraints from Fluid Inclusions,H-O-S Isotopes and Fluorite Sr-Nd Isotopes
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作者 Xiang Yan Bin Chen +1 位作者 Xiaoxia Duan Zhiqiang Wang 《Journal of Earth Science》 SCIE CAS CSCD 2021年第1期81-102,共22页
The Niujuan-Yingfang Pb-Zn-Ag deposit in northern North China Craton(NCC)is hosted at the contact zone between Permian biotite monzogranite and Hongqiyingzi Group migmatitic gneiss.The orebodies are structurally contr... The Niujuan-Yingfang Pb-Zn-Ag deposit in northern North China Craton(NCC)is hosted at the contact zone between Permian biotite monzogranite and Hongqiyingzi Group migmatitic gneiss.The orebodies are structurally controlled by NE-trending F1 fault.Mineralization can be divided into three stages:(1)siliceous-chlorite-pyrite stage,(2)quartz-Ag-base metal stage,and(3)fluorite-calcite stage.Four types of fluid inclusions were identified,including:(1)liquid-rich aqueous inclusions,(2)vapor-rich inclusions,(3)liquid-rich,solid-bearing inclusions,and(4)CO2-bearing inclusions.Mi-crothermometric measurements reveal that from stage I to III,the homogenization temperatures range from 317 to 262℃,from 297 to 192℃,and from 248 to 151℃,respectively,and the fluid salinities are in the ranges from 1.1 wt.%to 6.5 wt.%,1.2 wt.%to 6.0 wt.%and 0.7 wt.%to 4.0 wt.%NaCl equiva-lents,respectively.Fluid boiling and cooling are the two important mechanisms for ore precipitation according to microthermometric data,and fluid-rock interaction is also indispensable.Laser Raman spectroscopic analyses indicate the fluid system of the deposit is composed of CO2-NaCl-H2O±N2.Me-tallogenic fluorites yielded a Sm-Nd isochron age of 158±35 Ma.Theδ34SV-CDt values of sulfides range from-1.3‰ to 6.3‰,suggesting that the sulfur may be inherited from the basement metamorphic ig-neous rocks.Hydrogen and oxygen isotopic compositions of quartz indicate a metamorphic origin for the ore-forming fluid,and the proportion of meteoric water increased during the ore-forming processes.Sr-Nd isotopes of fluorites show a crustal source for the ore-forming fluid,with primary metamorphic fluid mixed with meteoric water during ascent to lower crustal levels.Combined with the geological,metallogenic epoch,fluid inclusions,H-O-S and Sr-Nd isotopes characteristics of the deposit,we suggest that the Niujuan-Yingfang deposit belongs to the medium-low temperature hydrothermal vein-type Pb-Zn-Ag polymetallic deposit,with ore-forming fluids dominantly originated from metamorphic fluids. 展开更多
关键词 fluid inclusion GEOCHRONOLOGY h-o-s isotopes fluorite Sr-Nd isotopes Niujuan-Yingfang Pb-Zn-Ag deposit NCC
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Tracing nitrate sources in one of the world's largest eutrophicated bays(Hangzhou Bay):insights from nitrogen and oxygen isotopes
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作者 Zhi Yang Jianfang Chen +6 位作者 Haiyan Jin Hongliang Li Zhongqiang Ji Yangjie Li Bin Wang Zhenyi Cao Qianna Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期86-95,共10页
Eutrophication caused by inputs of excess nitrogen(N) has become a serious environmental problem in Hangzhou Bay(China),but the sources of this nitrogen are not well understood.In this study,the August 2019 distributi... Eutrophication caused by inputs of excess nitrogen(N) has become a serious environmental problem in Hangzhou Bay(China),but the sources of this nitrogen are not well understood.In this study,the August 2019 distributions of salinity,nutrients [nitrate(NO_(3)^(-)),nitrite,ammonium,and phosphate],and the stable isotopic composition of NO_(3)^(-)(δ^(15)N and δ^(18)O) were used to investigate sources of dissolved inorganic nitrogen(DIN) to Hangzhou B ay.Spatial distributions of nitrate,salinity,and nitrate δ^(18)O indicate that the Qiantang River,the Changjiang River,and nearshore coastal waters may all contribute nitrate to the bay.Based on the isotopic compositions of nitrate in these potential source waters and conservative mixing of nitrate in our study area,we suggest that the NO_(3)^(- )in Hangzhou B ay was likely derived mainly from soils,synthetic N fertilizer,and manure and sewage.End-member modeling indicates that in the upper half of the bay,the Qiantang River was a very important DIN source,possibly contributing more than 50% of DIN in the bay head area.In the lower half of the bay,DIN was sourced mainly from strongly intruding coastal water.DIN coming directly from the Changjiang River made a relatively small contribution to Hangzhou Bay DIN in August 2019. 展开更多
关键词 nitrogen isotopes oxygen isotopes nitrogen cycle nitrate sources Hangzhou Bay
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Geology and S-Pb isotope geochemistry of the Hatu gold deposit in West Junggar,NW China:Insights into ore genesis and metal source
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作者 Shen Han Zhenju Zhou +6 位作者 Xiaohua Deng Yanshuang Wu Xi Chen Abulimiti Aibai Yong Wang Xiaoyu Jia Yanjing Chen 《Acta Geochimica》 EI CAS CSCD 2024年第6期1205-1222,共18页
The Hatu gold deposit is the largest historical gold producer of the West Junggar,western China,with an Au reserve of about 62 t.The orebodies were controlled by NE-,EW-,and NW-trending subsidiary faults associated wi... The Hatu gold deposit is the largest historical gold producer of the West Junggar,western China,with an Au reserve of about 62 t.The orebodies were controlled by NE-,EW-,and NW-trending subsidiary faults associated with the Anqi fault.This deposit exhibits characteristics typical of a fault-controlled lode system,and the orebodies consist of auriferous quartz veins and altered wall rocks within Early Carboniferous volcano-sedimentary rocks.Three stages of mineralization have been identified in the Hatu gold deposit:the early pyrite-albite-quartz stage,the middle polymetallic sulfides-ankerite-quartz stage,and late quartz-calcite stage.The sulfur isotopic values of pyrite and arsenopyrite vary in a narrow range from-0.8‰to1.3‰and an average of 0.4‰,the near-zeroδ~(34)S values implicate the thorough homogenization of the sulfur isotopes during the metamorphic dehydration of the Early Carboniferous volcano-sedimentary rocks.Lead isotopic results of pyrite and arsenopyrite(^(206)Pb/^(204)Pb=17.889-18.447,^(207)Pb/^(204)Pb=15.492-15.571,^(208)Pb/^(204)Pb=37.802-38.113)are clustered between orogenic and mantle/upper crust lines,indicating that the lead was mainly sourced from the hostrocks within the Early Carboniferous Tailegula Formation.The characteristics of S and Pb isotopes suggest that the ore-forming metals of the Hatu orogenic gold deposit are of metamorphogenic origin,associated with the continental collision between the Yili-Kazakhstan and Siberian plates during the Late Carboniferous. 展开更多
关键词 Hatu gold deposit Sulfur isotope Lead isotope Orogenic gold deposit West Junggar
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Processes involving soil CO_(2)dynamic in a sector of Chaco-Pampean plain,Argentina:An isotope geochemical approach
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作者 Sanci Romina Panarello Héctor 《Acta Geochimica》 EI CAS CSCD 2024年第5期947-958,共12页
The magnitude and spatial variability of CO_(2)surface emissions and processes involving CO_(2)released to the atmosphere from the soils are relevant issues in the context of climate change.This work evaluated CO_(2)f... The magnitude and spatial variability of CO_(2)surface emissions and processes involving CO_(2)released to the atmosphere from the soils are relevant issues in the context of climate change.This work evaluated CO_(2)fluxes and^(13)C/^(12)C ratio of vegetation,organic matter,and soil gases from no disturbed soils of Chaco Pampean Plain(Argentina)with different soil properties and environmental conditions(PL and PA units).Soil organic decomposition from individual layers was accompanied byδ^(13)C of total organic carbon(δ^(13)C-TOC)values more enriched to depth.δ^(13)C-TOC values in the upper soil profile~ca.0–15 cm were like the plant community of this area(~−33 to−29‰)whileδ^(13)CTOC varied stronger bellow horizon A,till~−24‰.Bothδ^(13)C-TOC and soilδ^(13)C-CO_(2)were similar(~−24 to 26‰)at deeper horizons(~50–60 cm).Toward the superficial layers,δ^(13)C-TOC andδ^(13)C-CO_(2)showed more differences(till~4‰),due influence of the diffusion process.Horizon A layer(~0–20 cm)from both PL and PA units contained the most enrichedδ^(13)C-CO_(2)values(~−15–17‰)because atmospheric CO_(2)permeated the soil air.A simple two-component mixing model between sources(atmosphericδ^(13)C-CO_(2)and soil CO_(2))confirmed that process.Isotopically,CO_(2)fluxes reflected the biodegradation of C3 plants(source),diffusive transport,and CO_(2)exchange(atmosphere/soil).Soil moisture content appeared as a determining factor in the diffusion process and the magnitude of CO_(2)surface emissions(12–60 g·m^(−2)·d^(−1)).That condition was confirmed by CO_(2)diffusion coefficients estimated by air-filled porosity parameters and soil radon gradient model. 展开更多
关键词 Soil CO_(2) Carbon isotopes isotope fractionation Radon gases
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Determination of Carbon and Nitrogen Isotope Fractions in Asparagine, Aspartic Acid, Threonine and Methionine
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作者 Lamzira Pharulava Levani Eliashvili +1 位作者 Vakhtang Betlemidze Bachana Sulava 《American Journal of Analytical Chemistry》 CAS 2024年第1期30-42,共13页
The nomenclature for compounds that are modified with isotopes is growing every day. Compounds can be modified with isotopes either individually, in a functional group or groups, or completely with all atomic centers ... The nomenclature for compounds that are modified with isotopes is growing every day. Compounds can be modified with isotopes either individually, in a functional group or groups, or completely with all atomic centers of the element. This diversity of isotope-modified compounds increases the range of researches that can be studied using them. Compounds modified with isotopes of carbon-13 or nitrogen-15 can be converted into carbon monoxide, carbon dioxide and molecular nitrogen. Currently, only the average value of carbon-13 or nitrogen-15 isotopes can be determined. However, by directly determining the atomic share of these isotopes in organic compounds modified with isotopes, information about the isotopic centers of the element can be obtained. The atomic fraction of an element is defined as a single carbon or nitrogen isotope-modified center or centers, or all centers that are isotope-modified with that element at the same time. Carbon-13 or nitrogen-15 isotopes’ atomic fraction can be determined molecularly or with fragment ions of different elemental content, or both. This makes the method self-verifying, increasing the accuracy and reliability of the results obtained. Amino acids, such as asparagine, aspartic acid, methionine, and threonine, are essential for the human body. This proposed method of isotopic analysis will increase the possibilities for scientific research using these compounds. 展开更多
关键词 ASPARAGINE Aspartic Acid THREONINE METHIONINE Mass Spectrometer isotopic Analysis Atomic Share
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The source of lithium in Lakkor Co Salt Lake on Qinghai-Tibet Plateau,China:evidence from hydrochemical characteristics and boron isotope
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作者 Zheng Yan Li Bin Kai Li +2 位作者 Mao-Yong He Xue Qin Wen Jiang Di Zhou 《Acta Geochimica》 EI CAS CSCD 2024年第5期933-946,共14页
The availability of lithium resources is of great significance for the development of modern technologies,as well as for civil and military industries.The Qinghai-Tibet Plateau is a region known for its abundance of l... The availability of lithium resources is of great significance for the development of modern technologies,as well as for civil and military industries.The Qinghai-Tibet Plateau is a region known for its abundance of lithium-rich salt lakes.However,the specific origin of lithium in these lakes is still unknown,which hinders the advancement of the lithium resource business in this region.To research this issue,this study involved the collection of 20 samples from Lakkor Co Salt Lake on Qinghai-Tibet Plateau,encompassing samples of surface brine,cold springs,fresh lakes,and recharge rivers.The composition of anions and cations in these samples was determined.Furthermore,the analysis extensivelyutilizedthePiperthree-linediagram,Gibbs model,and ion proportion coefficient.The findings of this study indicate that as the moves from the recharge water system to salt lake,there is a transition in water type from strong carbonate to moderate carbonate and weak carbonate,as well as Na sulfate.This research based on a similar source of both lithium and boron,utilized ion correlation analysis and boron isotope study in the Lakkor Co area,and analyzed the source and transporting process of lithium.The main origin of lithium in Lakkor Co is the dissolution of lithiumrich rocks,recharge water systems,and deep hydrothermal fluids.These findings are highly significant in enhancing the foundational data of lithium-rich brine resources in the Qinghai-Tibet Plateau and are beneficial for assessing the future development of such deposits. 展开更多
关键词 LITHIUM Hydrochemical Li-rich Salt lake Boron isotope
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Catagenetic type of manganese ores:REE and isotope(δ^(13)C,δ^(18)O)geochemical features(on the example of the Usa deposit,Russia)
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作者 Vladimir N.Kuleshov Andrey Yu.Bychkov +1 位作者 Irina Yu.Nikolaeva Maria E.Tarnopolskaia 《Acta Geochimica》 EI CAS CSCD 2024年第6期1133-1152,共20页
Chemical(REE and major elements)and isotope(δ^(13)C,δ^(18)O)composition of carbonate manganese ores and manganese-bearing carbonates of the Usa deposit(Siberia,Russia)were studied.Received data on the composition of... Chemical(REE and major elements)and isotope(δ^(13)C,δ^(18)O)composition of carbonate manganese ores and manganese-bearing carbonates of the Usa deposit(Siberia,Russia)were studied.Received data on the composition of REE exhibit both the distinct negative(Ce/Ce*_(PAAS)<1)and positive(Ce/Ce*_(PAAS)>1)cerium anomalies and the positive Eu-anomaly(Eu/Eu*_(PAAS)>1).Negative Eu-anomalies are not observed.The contents of Mn,Fe,REE,and Ce-anomalies show a positive correlation with each other.Ce-anomalies and the amount of manganese and REE in relation to the carbon isotope composition(δ^(13)C)show a negative relationship and indicate that oxidized carbon of organic matter played an important role in the concentration of manganese and REE in manganese ores.The chemical and isotope composition of examined rocks indicates on secondary formation of Mnores.Two major phases and sources are distinguished in the ore-forming process characterized by diff erent chemical(REE and ore elements)and isotope composition:(i)highgrade manganese ores(with high contents of REE and light carbon isotope composition)and(ii)low-grade manganese ores(with low contents of REE and heavy carbon isotope composition). 展开更多
关键词 Manganese ore REE isotope composition CATAGENESIS CAMBRIAN Siberia
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A bulk extraction method to determine the stable isotope ratios of iron,nickel,copper,zinc,and cadmium in seawater using multi-collector inductively coupled plasma mass spectrometry
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作者 Zhan Shen Yuncong Ge +3 位作者 Jiahui Liu Wenkai Guan Wenfeng Hu Ruifeng Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期125-137,共13页
The oceanic trace metals iron(Fe),nickel(Ni),copper(Cu),zinc(Zn),and cadmium(Cd)are crucial to marine phytoplankton growth and global carbon cycle,and the analysis of their stable isotopes can provide valuable insight... The oceanic trace metals iron(Fe),nickel(Ni),copper(Cu),zinc(Zn),and cadmium(Cd)are crucial to marine phytoplankton growth and global carbon cycle,and the analysis of their stable isotopes can provide valuable insights into their biogeochemical cycles within the ocean.However,the simultaneous isotopic analysis of multiple elements present in seawater is challenging because of their low concentrations,limited volumes of the test samples,and high salt matrix.In this study,we present the novel method developed for the simultaneous analysis of five isotope systems by 1 L seawater sample.In the developed method,the NOBIAS Chelate-PA1 resin was used to extract metals from seawater,the AG MP-1M anion-exchange resin to purify Cu,Fe,Zn,Cd,and the NOBIAS Chelate-PA1 resin to further extract Ni from the matrix elements.Finally,a multi-collector inductively coupled plasma mass spectroscope(MC-ICPMS)was employed for the isotopic measurements using a doublespike technique or sample-standard bracketing combined with internal normalization.This method exhibited low total procedural blanks(0.04 pg,0.04 pg,0.21 pg,0.15 pg,and 3 pg for Ni,Cu,Fe,Zn,and Cd,respectively)and high extraction efficiencies(100.5%±0.3%,100.2%±0.5%,97.8%±1.4%,99.9%±0.8%,and 100.1%±0.2%for Ni,Cu,Fe,Zn,and Cd,respectively).The external errors and external precisions of this method could be considered negligible.The proposed method was further tested on the seawater samples obtained from the whole vertical profile of a water column during the Chinese GEOTRACES GP09 cruise in the Northwest Pacific,and the results showed good agreement with previous related data.This innovative method will contribute to the advancement of isotope research and enhance our understanding of the marine biogeochemical cycling of Fe,Ni,Cu,Zn,and Cd. 展开更多
关键词 trace metal stable isotopes seawater bulk extraction
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Nitrogen isotope stratigraphy of the Early Cambrian successions in the Tarim Basin:Spatial variability of nitrogen cycling and its implication for paleo-oceanic redox conditions
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作者 Bi Zhu Xuefeng Li +1 位作者 Lu Ge Yongquan Chen 《Acta Geochimica》 EI CAS CSCD 2024年第4期785-801,共17页
The Early Cambrian represents a critical time period characterized by extraordinary biological innovations and dynamic redox conditions in seawaters.Nitrogen isotopic signatures of ancient sediments have the potential... The Early Cambrian represents a critical time period characterized by extraordinary biological innovations and dynamic redox conditions in seawaters.Nitrogen isotopic signatures of ancient sediments have the potential to elucidate the evolutionary path of marine redox states and the biogeochemical nitrogen cycle within the water column of the Early Cambrian ocean.While existing research on this topic has predominantly focused on South China,the exploration of other continental margins has been limited,leaving contradictory hypotheses untested.In this study,pairedδ^(15)N andδ^(13)C org analyses were performed on the Lower Cambrian successions from the Shiairike section(inner ramp)and Well Tadong 2(deep shelf/basin)in the northwestern and eastern Tarim Basin,respectively.Our data from the Shiairike section reveal a discernible shift in the operation of different nitrogen cycles for the black chert-shale unit,also referred to as the black rock series in Chinese literature,of the Yurtus Formation(Fortunian stage to lower Stage 3).Oscillatingδ^(15)N values for its lower part are suggestive of alternating anaerobic assimilation of NH 4+and denitrification/anammox.This is likely attributed to a shallow,unstable chemocline consistent with the upwelling and incursion of deep,anoxic waters during a major transgression.In contrast,aerobic nitrogen cycling,indicated by positiveδ^(15)N values of>2‰,dominated the upper part alongside a reduction in upwelling intensity.On the other hand,theδ^(15)N signatures of Xishanbulake and Xidashan Formations of Well Tadong 2,which encompass a time interval from the Cambrian Fortunian Age to Age 4,are indicative of N_(2)fixation by diazotrophs as the major nitrogen source.The two studied intervals,although not time-equivalent,exhibit separated states of nitrogen cycling at least during the deposition of the Yurtus black rock series.The spatially different nitrogen cycling of the studied sections is compatible with a redox-stratified ocean during the deposition of the Yurtus black rock series.The build-up of a NO_(3)−reservoir and aerobic nitrogen cycling in seawater was largely restricted to near-shore settings whereas anaerobic nitrogen cycling dominated by N_(2)fixation served as the main nitrogen uptake pathway in off-shore settings. 展开更多
关键词 Nitrogen isotopes Early Cambrian TARIM Black rock series
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Rebuilding the theory of isotope fractionation for evaporation of silicate melts under vacuum condition
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作者 Jie Wang Yun Liu 《Acta Geochimica》 EI CAS CSCD 2024年第4期661-676,共16页
Isotope eff ects are pivotal in understanding silicate melt evaporation and planetary accretion processes.Based on the Hertz-Knudsen equation,the current theory often fails to predict observed isotope fractionations o... Isotope eff ects are pivotal in understanding silicate melt evaporation and planetary accretion processes.Based on the Hertz-Knudsen equation,the current theory often fails to predict observed isotope fractionations of laboratory experiments due to its oversimplified assumptions.Here,we point out that the Hertz-Knudsen-equation-based theory is incomplete for silicate melt evaporation cases and can only be used for situations where the vaporized species is identical to the one in the melt.We propose a new model designed for silicate melt evaporation under vacuum.Our model considers multiple steps including mass transfer,chemical reaction,and nucleation.Our derivations reveal a kinetic isotopic fractionation factor(KIFF orα)αour model=[m(^(1)species)/m(^(2)species)]^(0.5),where m(species)is the mass of the reactant of reaction/nucleation-limiting step or species of diffusion-limiting step and superscript 1 and 2 represent light and heavy isotopes,respectively.This model can eff ectively reproduce most reported KIFFs of laboratory experiments for various elements,i.e.,Mg,Si,K,Rb,Fe,Ca,and Ti.And,the KIFF-mixing model referring that an overall rate of evaporation can be determined by two steps jointly can account for the eff ects of low P_(H2)pressure,composition,and temperature.In addition,we find that chemical reactions,diffusion,and nucleation can control the overall rate of evaporation of silicate melts by using the fitting slope in ln(−ln f)versus ln(t).Notably,our model allows for the theoretical calculations of parameters like activation energy(E_(a)),providing a novel approach to studying compositional and environmental eff ects on evaporation processes,and shedding light on the formation and evolution of the proto-solar and Earth-Moon systems. 展开更多
关键词 EVAPORATION Kinetic isotopic fractionation Chemical kinetics Hertz-Knudsen equation CAIS
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Precise and accurate Ga isotope ratio measurements of geological samples by multi-collector inductively coupled plasma mass spectrometry
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作者 Yuxu Zhang Pan Qiao +2 位作者 Chuanwei Zhu Haifeng Fan Hanjie Wen 《Acta Geochimica》 EI CAS CSCD 2024年第6期1054-1064,共11页
Gallium isotope is a potential geochemical tool for understanding planetary processes,environmental pollution,and ore deposit formation.The reported Ga isotope compositions(δ^(71)Ga NIST994 values)of some internation... Gallium isotope is a potential geochemical tool for understanding planetary processes,environmental pollution,and ore deposit formation.The reported Ga isotope compositions(δ^(71)Ga NIST994 values)of some international geological standards,such as BCR-2 and BHVO-2 basalts,exhibit inconsistencies between diff erent laboratories.During mass spectrometry analysis,we found thatδ^(71)Ga NIST994 values of geological standards with or without the correction of the interference of^(138)Ba^(2+)(mass/charge ratio=69)on 69 Ga show signifi cant isotope off sets,and thus effi cient separation of Ba and correcting the interference of^(138)Ba^(2+)are both crucial to obtain accurateδ^(71)Ga values.By comparingδ^(71)Ga NIST994 values(relative to NIST SRM 994 Ga)of the same geostandards from diff erent laboratories,we suggest that the isotopic heterogeneity from NIST SRM 994 Ga is one of the key reasons for the inconsistencies inδ^(71)Ga NIST994 values of BCR-2 and BHVO-2.To facilitate inter-laboratory comparisons,we measured the Ga isotopic compositions of 11 geological reference materials(including Pb-Zn ore,bauxite,igneous rocks,and loess)and two Ga solution standards(NIST SRM 3119a and Alfa Aesar).Theδ^(71)Ga NIST994 andδ^(71)Ga IPGP values of these reference materials vary from 1.12‰to 2.63‰and−0.13‰to 1.38‰,respectively,and can be used to evaluate the precision and accuracy of Ga isotope data from diff erent laboratories. 展开更多
关键词 Ga isotopes MC-ICP-MS Reference materials Chemical purification Ba interference
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南秦岭柞水-山阳矿集区金盆梁金矿床成因——来自流体包裹体及C-H-O-S-Pb同位素的制约
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作者 葛战林 顾雪祥 +5 位作者 章永梅 高永宝 郝迪 郑艳荣 刘明 王辉 《矿床地质》 CAS CSCD 北大核心 2024年第4期877-898,共22页
金盆梁是南秦岭柞水-山阳矿集区勘查的一处微细浸染型金矿床,矿床成因与成矿机制尚不清楚。矿体产于上泥盆统桐峪寺组粉砂质板岩和钙质板岩中,以浸染状、脉状金锑矿化为主,成矿过程可划分为3个阶段:毒砂-黄铁矿-硅化阶段(Ⅰ)、石英-辉锑... 金盆梁是南秦岭柞水-山阳矿集区勘查的一处微细浸染型金矿床,矿床成因与成矿机制尚不清楚。矿体产于上泥盆统桐峪寺组粉砂质板岩和钙质板岩中,以浸染状、脉状金锑矿化为主,成矿过程可划分为3个阶段:毒砂-黄铁矿-硅化阶段(Ⅰ)、石英-辉锑矿-白铁矿±锑氧化物阶段(Ⅱ)和方解石-石英阶段(Ⅲ)。流体包裹体及C-H-O-S-Pb同位素研究结果显示,Ⅱ阶段主要为金锑矿化,以H_(2)O-NaCl两相包裹体占绝对优势,成矿流体属于中温(200~290℃)、低盐度(w(NaCl_(eq))为0~6.0%)、低密度(0.64~0.99 g/cm^(3))的H_(2)O-NaCl±CO_(2)体系,以循环大气降水为主。无矿化的Ⅲ阶段主要发育H_(2)O-NaCl两相包裹体,含少量CO_(2)-H_(2)O-NaCl±CH_(4)、纯CO_(2)±CH_(4)及含子晶多相包裹体,流体以中低温(140~280℃)、低盐度(w(NaCl_(eq))为2.0%~8.0%)、低密度(0.68~1.02 g/cm^(3))的富CO_(2)-H_(2)O-NaCl±CH_(4)体系为主,或存在少量高温、高盐度、高密度H_(2)O-NaCl体系的岩浆热液混入。硫化物δ^(34)S值为较大负值(−12.50‰~−10.20‰),Pb同位素组成具上地壳源铅特征,成矿物质主要来源于围岩地层。综合研究表明,金盆梁金矿的成因类型属于卡林型金矿,水-岩反应(围岩硫化作用)是金富集沉淀的主要机制。 展开更多
关键词 矿床成因 流体包裹体 C-h-o-s-Pb同位素 金盆梁金矿床 南秦岭
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