半宽金矿的成因类型和成矿机制——矿物包裹体和同位素研究的启示  

GENETIC TYPE AND METALLOGENIC MECHANISM OF BANKUAN GOLD DEPOSIT IN SPECIAL REFERENCE TO THE STUDIES OF FLUID INCLUSIONS AND ISOTOPES IN MINERALS

作　　者：陈衍景[1] 富士谷[2] 金持跃[2] 

机构地区：[1]中国科学院地球化学研究所,贵阳550002 [2]南京大学地球科学系,南京210008

出　　处：《矿物学报》1992年第4期289-298,共10页Acta Mineralogica Sinica

基　　金：国家自然科学基金

摘　　要：半宽金矿的含金石英脉产于河南崤山地体铁铜沟组底部砾岩的层间破碎带或铁钢沟组与下伏结晶基底的不整合面附近。矿物包裹体成分显示:成矿热液沿结晶基底内的通道运移至铁铜沟组时,发生了成分和性质的突然改变,导致金大量沉淀。矿床应属砾岩层控型。137个测温数据集中于400～340℃,330～220℃,180～160℃,表明矿化经历了三期;氧同位素研究证明成矿热液由早期变质热液向晚期大气降水热液演化,硫、铅同位素显示成矿物质来源复杂,但以深源为主。研究表明,矿床由中生代时沿马超营断裂向北的陆内俯冲诱发的变质分泌作用所形成。Auriferous quartz veins in the Bankuan gold deposit occur in the inter layer broken zone of the basal conglomerate of the Tietonggou Formation or at the disconformity between the Tietonggou Formation and the crystalline basement. The composition of fluid inclusions in the minerals indicates that the properties and composition of ore-forming hydrothermal solutions show a drastical change soon after the solutions reached the Tietonggou Formation from the crystalline basement, resulting in gold precipitation from the solutions. So the Bankuan gold deposit can be assigned to the conglomerate strata-bound-type deposits. 137 thermometric data are concentrated in the three ranges 400～340℃, 330～220℃ and 180～160℃, representing three episodes of metallogenesis·Oxygen isotope studies demonstrate the evolution of ore-forming hydrothermal solutions from early metamorphic to late meteoric. Diversity of ore-forming materials dominated by deep-source material is supported by sulphur and lead isotope data. From the above discussions it may be concluded that the deposit formed by metamorphism induced as a result of Mesozoic northward intracontinental subduction along the Machaoyeng fault.

关 键 词：金矿床 类型 成矿 矿物包体 同位素 

分 类 号：P618.510.2[天文地球—矿床学]