南祁连裕龙沟铜镍硫化物矿床Re-Os同位素物质来源示踪研究  

Re-Os Isotopic Analysis of the Yulonggou Cu-Ni Sulfide Deposit in the South Qilian Mountain

作　　者：高永宝[1,2] 李文渊[1] 张照伟[1,2] 李超[3] 周利敏[3] 郭周平[1] 张江伟[1] 李侃[1] 钱兵[1] 王亚磊[1] 谭文娟[1] 

机构地区：[1]西安地质矿产研究所,陕西西安710054 [2]长安大学地球科学与国土资源学院,陕西西安710054 [3]国家地质实验测试中心,北京100037

出　　处：《地球学报》2012年第6期899-906,共8页Acta Geoscientica Sinica

基　　金：中国地质调查局地质调查项目(编号:1212011121088;1212011121092;1212011220897和1212010911032);国家自然科学基金项目(编号:40772062;41102050);"十一五"国家科技支撑计划项目(编号:2006BAB01A01)联合资助

摘　　要：南祁连日月山—化隆基性-超基性岩带发育多个与铜镍矿化有关的岩体,岩石类型主要有角闪辉石岩、辉长岩、苏长岩、辉石岩、辉橄岩等,其中裕龙沟基性杂岩体形成于(442.4±1.6)Ma。通过对裕龙沟铜镍矿床稀疏浸染状矿石中硫化物的Re-Os及S同位素物质来源示踪研究,其187Os/188Os初始比值为0.2239～0.2757,γOs为80～123,δ34S为0.8‰～2.4‰,表明其物质来源具有壳-幔混合特征,壳源Os的加入量为20%～28%,地壳物质的加入可能是裕龙沟岩体富集成矿的重要因素。There are lots of intrusive rocks composed of amphibole pyroxenite, gabbro, norite, pyroxenite and augite peridotite in Riyueshan-Hualong basic-ultrabasic rock belt of South Qilian Mountain, which are related to copper-nickel mineralization. The Yulonggou basic complex was formed at （442.4±1.6） Ma. Re and Os concentrations as well as Os and S isotopic analyses were obtained for sulfides in disseminated sulfide ores from the Yulonggou Cu-Ni deposit, with the purpose of assessing the role of crustal contamination in the formation of the Yulonggou Cu-Ni deposit. The initial ^187Os/^188Os ratios are from 0.2239 to 0.2757, the yos values are from 80 to 123, and the δ34S values are from 0.8‰ to 2.4‰; these data suggest that the ore-forming materials were derived from both the mantle and the crust. The content of crust-derived Os is estimated to be 20%-28%. The crustal contamination might have been one of the most important factors for copper and nickel accumulation in the Yulonggou intrusion.

关 键 词：RE-OS同位素 铜镍硫化物矿床 裕龙沟 化隆 南祁连 

分 类 号：P611.11[天文地球—矿床学] P597.2[天文地球—地质学]