西秦岭降扎地区寒武系层控金矿床中Au-Se共同富集成矿机制  

Mechanism of Au and Se co- enrichment in Cambrian Stratabound Gold Deposits in Jiangzha, Western Qinling Mountains, China

作　　者：刘家军[1] 郑明华[2] 刘建明[3] 卢文全[4] 刘显凡[2] 

机构地区：[1]中国科学院地球化学研究所矿床地球化学开放研究实验室,贵州贵阳550002 [2]成都理工学院矿床地质研究所,四川成都610059 [3]中国科学院矿物资源探查研究中心,北京100101 [4]国土资源部矿产综合利用研究所,四川成都610041

出　　处：《地球化学》2001年第2期155-162,共8页Geochimica

基　　金：国家自然科学基金资助项目! (49773197);中国科学院 1997年度"百人计划"资助项目;国家重点基础发展规划资助项目!(G1999043208)

摘　　要：西秦岭降扎地区寒武系中的层控金矿床，产于由碳质硅岩和碳质板岩组成的硅岩建造中。研究表明，无论是围岩还是金矿石，均普遍含有较高的硒，达到工业综合利用的要求，在局部地段甚至可以圈出独立的硒矿体。在金矿石中，硒主要呈独立矿物和以类质同象形式存在于硫化物中，且硒与金呈密切的正相关关系。尤为重要的是，在金矿石中常常见到自然金与一些硒矿物紧密共生，说明 Au、 Se可能以 Au- S- Se或 Au- Se络合物形式进行迁移。由于沸腾的成矿流体与下渗的富氧冷水混合而发生氧化还原作用，导致了 Au和 Se的共同富集成矿。The Cambrian stratabound gold deposits in Jiangzha, western Qinling Mountains are hosted in the silicalite formation composed of black chert and carbonaceous slate. Studies have shown that Se is so high in abundance either in wall rocks or in gold ores as to reach the grade of industrial value for comprehensive utilization. In local places some independent Se orebodies can even be delineated. In gold ores Se is present mainly as independent minerals, or isomorphously in sulfides. In addition, Se is closely positively correlated with Au. What is more important is that in the gold ores native gold is commonly observed ultimately intergrowing with some selenium minerals. On the basis of this unique phenomenon, it is thought that gold and selenium are possibly transported by Au- S- Se or Au- Se complex. The co- enrichment of Au and Se is attributed mainly to boiling of ore fluids and their mixing with shallow- seated oxygen- bearing water.

关 键 词：层控金矿床 西秦岭 寒武系 成矿作用 金-钪共生机理 成矿机制 

分 类 号：P618.51[天文地球—矿床学] P595[天文地球—地质学]