云南勐海勐满金矿床的地球化学特征及成因  

Geochemical Characteristics and Genesis of the Mengman Carlin Type-like Gold Deposit in Menghai County,Yunnan Province

作　　者：杨贵来[1] 杨伟光 罗梅[3] 和中华 罗石生 杨柱平 王翔[3] 

机构地区：[1]中国地质大学地球科学与资源学院,北京100083 [2]云南地质矿产资源股份有限公司,云南昆明650215 [3]成都理工大学地球科学学院,四川成都610059

出　　处：《现代地质》2007年第4期667-674,共8页Geoscience

基　　金：国家重点基础研究发展规划项目(2004CB412603)

摘　　要：云南勐满金矿床是"三江"褶皱系南端的一个微细粒—红土复合型金矿床,矿床达中型规模,并具有成为大型金矿的找矿远景。赋矿层位为上元古界澜沧群片岩和中侏罗统碎屑岩及第四纪残坡积层。文章提供了勐满金矿的矿床地质特征、流体包裹体以及S、H、O和Pb同位素地球化学研究资料,并对矿床成因和成矿作用进行了分析。研究表明:勐满原生金矿床具有与卡林型金矿床类似的地质和地球化学特征;其成矿物源主要是上元古界澜沧群曼来组浅变质岩系和中侏罗统花开左组碎屑岩系;流体包裹体及S、H、O同位素研究一致显示成矿流体主要为大气降水。成矿作用经历了原始含矿岩系(矿源层)的形成阶段及金的活化、迁移和富集阶段。区域构造及岩浆活动是引起金矿活化迁移和富集的主要因素。进一步加强对含矿层位的岩相古地理与岩石学研究、加强控矿构造的分析、确定控矿构造的力学性质及与区域主干断裂之间的配套关系,是今后找矿工作中需要特别注意的问题。Mengman gold deposit in Yunnan is a middle scale composite micrograined-and laterite-type gold deposit, located at the south end of Sanjiang fold belt with a potential to become a large deposit for prospecting. The gold deposit is hosted in the schists of the Proterozoic Lancang Group, Middle Jurassic clastic rocks and Quaternary residual-slide rock and soil. This paper provides the data on geological setting, fluid inclusions and isotopic geochemistry of S, H, O, and Pb isotopes, and discusses the genesis of the gold deposit. The studies show that, the primary gold deposit is similar to Carlin-type gold deposit in geological and geochemical characteristics. The metal sources for mineralization are likely the Upper Proterozoic low-grade metamorphic rock series of the Manlai Formation of the Lancang Group, and the Middle Jurassic clastic rock series of the Huakaizuo Formation. The evidences from fluid inclusions and S, H, O and Pb isotopes indicate that ore-forming hydrothermal fluids mainly came from meteoric water. The mineralization of gold could be divided into two stages ： the formation of gold source materials （preliminary concentration of gold）, and the activation-migration-concentration of gold. The regional tectonic movement and magmatism are likely the major factors leading to activation, migration and concentration of gold. Therefore, it is important for the further prospecting to reinforce the study in petrology and petrofacies and paleogeography of the ore-bearing formations, and to reinforce the study of ore-controlling structures, their mechanical properties and the relationship with the major regional faults. 　

关 键 词：云南勐满 微细粒型金矿 矿床地球化学 矿床成因 

分 类 号：P618.51[天文地球—矿床学]