Sources of ore-forming fluids and metallic materials in the Jinwozi lode gold deposit,eastern Tianshan Mountains of China

【作者】 刘伟； 李新俊； 邓军；

【Author】 LIU Wei,LI Xinjun~1 &DENG Jun 1.Key Laboratory of Research for Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100101,China; 2.School of the Earth and Land Resources,China University of Geosciences(Beijing),Beijing 100083,China

【机构】 Key Laboratory of Research for Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences； School of the Earth and Land Resources,China University of Geosciences(Beijing)；

【摘要】 <正>This paper presents gas compositions and H-,O-isotope compositions of sulfide-and quartz-hosted fluid inclusions,and S-,Pb-isotope compositions of sulfide separates collected from the principal Stage 2 ores in Veins 3 and 210 of the Jinwozi lode gold deposit,eastern Tianshan Mountains of China.Fluid inclusions trapped in quartz and sphalerite are dominantly primary.H- and O-isotopic compositions of pyrite-hosted fluid inclusions indicate two major contributions to the ore-forming fluid that include the degassed magma and the meteoric-derived but rock ¹⁸O-buffered groundwater.However,H-and O-isotopic compositions of quartz-hosted fluid inclusions essentially suggest the presence of groundwater.Sulfide-hosted fluid inclusions show considerably higher abundances of gaseous species CO₂,N₂,H₂S,etc.than quartz-hosted ones.The linear trends among inclusion gaseous species reflect the mixing tendency between the gas-rich magmatic fluid and the groundwater.The relative enrichment of gaseous species in sulfide-hosted fluid inclusions. coupled with the banded ore structure indicating alternate precipitation of quartz with sulfide minerals, suggests that the magmatic fluid has been inputted to the ore-forming fluid in pulsation.Sulfur and lead isotope compositions of pyrite and galena separates indicate an essential magma derivation for sulfur but the multiple sources for metallic materials from the mantle to the bulk crust.更多还原

【Abstract】 This paper presents gas compositions and H-,O-isotope compositions of sulfide-and quartz-hosted fluid inclusions,and S-,Pb-isotope compositions of sulfide separates collected from the principal Stage 2 ores in Veins 3 and 210 of the Jinwozi lode gold deposit,eastern Tianshan Mountains of China.Fluid inclusions trapped in quartz and sphalerite are dominantly primary.H- and O-isotopic compositions of pyrite-hosted fluid inclusions indicate two major contributions to the ore-forming fluid that include the degassed magma and the meteoric-derived but rock ¹⁸O-buffered groundwater.However,H-and O-isotopic compositions of quartz-hosted fluid inclusions essentially suggest the presence of groundwater.Sulfide-hosted fluid inclusions show considerably higher abundances of gaseous species CO₂,N₂,H₂S,etc.than quartz-hosted ones.The linear trends among inclusion gaseous species reflect the mixing tendency between the gas-rich magmatic fluid and the groundwater.The relative enrichment of gaseous species in sulfide-hosted fluid inclusions. coupled with the banded ore structure indicating alternate precipitation of quartz with sulfide minerals, suggests that the magmatic fluid has been inputted to the ore-forming fluid in pulsation.Sulfur and lead isotope compositions of pyrite and galena separates indicate an essential magma derivation for sulfur but the multiple sources for metallic materials from the mantle to the bulk crust.更多还原