北祁连山石居里铜矿硅、铅、硫同位素组成特征  

Silicon-lead-sulfur isotopic constitution of Shijuli copper deposits of North Qilian Mountains

作　　者：宋忠宝[1] 杨合群[1] 邬介人[1] 

机构地区：[1]西安地质矿产研究所,陕西西安710054

出　　处：《西北地质》2003年第2期83-86,共4页Northwestern Geology

基　　金：国土资源大调查项目"甘肃北祁连山错沟-寺大隆一带铜矿预测与评价"(编号200010200152);"甘肃省石居里一带铜矿评价"(编号:K4.2.3.4)资助

摘　　要：石居里铜矿是北祁连山典型的塞浦路斯型铜矿,通过对矿石和围岩的硅、铅和硫同位素研究,作者认为,硅同位素组成δ30Si(-0.9‰～-0.2‰)与火山岩的δ30Si范围一致(落在火山岩范围内),由此可知是火山成因的产物。矿石中黄铁矿、黄铜矿的铅同位素组成同各矿区范围玄武岩的铅同位素组成相近,以此为线索结合Rona(1983)的试验规律,推断本区成矿金属主要来源于蚀变玄武岩。硫同位素δ34S值变化于1.5‰～8.88‰,矿化剂硫来源于火山岩源与海水源的不同比例混合。Shijuli copper deposits are typical Cyprustype ones in the western part of North Qilian Mountains On the basis of the siliconleadsulfur isotope constitution of the ores and wall rocks in Shijuli ore area, the author thinks that it is volcanic genesis The δ30Si(-09‰～-02‰) from jaspilite and quartz of ores show that they are consistent with ones of basaltic rocks Lead isotope compositions of pyrites and chlcopyrites are similar to those of basalts in the area Thus, it is considered that the lead from ores comes mainly from altered basalts However, sulfur in the deposits may be the results of reactions to different degrees between seawater and basaltic rocks, because δ34S in pyrites and chlcopyrites varies between 15‰～888‰

关 键 词：石居里 塞浦路斯型矿床 稳定同位素 北祁连山 

分 类 号：P611[天文地球—矿床学]