青海双朋西金铜矿床的成矿流体特征及流体来源  

CHARACTERISTICS OF ORE-FORMING FLUID AND GENESIS OF THE SHUANGPENGXI GOLD-COPPER DEPOSITIN QINGHAI PROVINCE

作　　者：傅晓明[1] 戴塔根[1] 息朝庄 刘伟 刘旭[1] 

机构地区：[1]中南大学地学与环境工程学院,长沙410083 [2]湖南有色金属控股集团,长沙410015

出　　处：《地质找矿论丛》2010年第1期24-29,共6页Contributions to Geology and Mineral Resources Research

基　　金：国家973项目(编号2002CG412607);国家科技攻关项目(编号2004BA615-02);湖南省自然科学基金(编号07JJ6071)资助

摘　　要：通过对双朋西金铜矿床流体包裹体岩相学、测温学及矿石铅、硫同位素等的分析,研究成矿流体性质和演化、成矿流体来源。结果表明:流体包裹体主要为气液两相包裹体,另有少量液相和含子矿物包裹体。包裹体液相成分阳离子以Na+,K+,Ca2+为主,阴离子主要以SO42-,Cl-为主;气相以H2O,CO2为主。均一温度范围为210~370℃和370~460℃,盐度3.0%~6.5%,密度集中于0.600~0.800 g/cm3,压力主要为8.0~20.0 MPa,为中高温、中等盐度、中等密度、中等压力的成矿流体。铅同位素206Pb/204Pb为18.058~18.710,207Pb/204Pb为15.581~15.641,208Pb/204Pb为38.191~38.531,δ(34S)为+3.1×10-3^+6.2×10-3,平均值为+4.42×10-3,成矿流体铅、硫同位素来源为壳幔混合源。Based on study of the fluid inclusion, thermometry and isotope analyses, the characteristics of ore-forming fluid, fluid evolution and the origin of Shuangpengxi gold-copper deposit were discussed and systematically studied. The results showed that these inclusions are generally consisted of 2 （gas and liquid） phases, and minor liquid and solid sub-mineral phase. The liquid phase includes cations dominated by Na^＋ ,K^＋ ,Ca^＋2 and ions by SO4^2- ,Cl^- and gas phase H2O,CO2. The homogenization temperature, salinity and density and pressure of the fluid inclusions are medium ones ranged from 210℃ to 460℃ ,and 3.0% to 6.5%,and 0. 600 to 0. 800 g/cm^3 ,and 8.0 to 20.0 MPa, respectively. Analysis of ^206Pb/^204Pb is in range of 18. 058-18. 710, ^207Pb/^204Pb 15. 581-15. 641, ^208Pb/^204Pb 38. 191-38. 531; δ（^34S） value ＋3.1×10^-3-＋6.2 ×10^-3 （average ＋4.42×10^-3） indicating the crust-mantle mixed origin of Pb and S.

关 键 词：成矿流体 包裹体 双朋西金铜矿 青海省 

分 类 号：P611[天文地球—矿床学] P618[天文地球—地质学]