江西金山金矿成矿物质来源的铂族元素证据  

THE PLATIUM GROUP ELEMENTS EVIDENCE FOR ORIGIN OF ORE-FORMING MASS IN JINSHAN GOLD DEPOSIT, JIANGXI PROVINCE

作　　者：李晓峰[1] 华仁民[2] 毛景文[1] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]南京大学地球科学系,南京210093

出　　处：《地质与勘探》2002年第6期13-16,共4页Geology and Exploration

基　　金：国家重点基础研究发展规划项目(G1999043209;G1999043211);国家自然科学基金项目(4973)资助。

摘　　要：金山金矿位于我国著名的德兴铜金矿集区内,是一个与韧性剪切带有关的超大型金矿床。对该矿床矿(岩)石铂族元素分析结果表明:与原始地幔相比,各类岩石明显亏损铂族元素。碳质千枚岩、超糜棱岩和含金石英脉中铂族元素原始地幔标准化分配模式基本一致。从碳质千枚岩、(超)糜棱岩到含金石英脉铂族元素总量逐渐降低的趋势,Pd/Pt和Pt/Ir值逐渐减小;Pd和Au具有明显的负相关(r=-0.9443),而Ir和Pt的相关性不明显。这说明在热液流体作用过程中,铂族元素Ir组元素和Pd元素具有较为一致的地球化学行为,同时也存在Pd组元素之间的分离现象。碳质千枚岩、糜棱岩、超糜棱岩和含金石英脉的稀土元素分配模式也十分相似,具有右倾缓倾的特点。铕亏损较明显(δEu=0.62～0.71),而铈基本没有明显的富集或者亏损(δCe=0.97～1.01)。稀土元素地球化学表明成矿物质来源与围岩碳质千枚岩有密切关系。结合前人对金山金矿成矿物质来源的研究,认为铂族元素可以做为地球化学示踪剂在流体/岩石相互作用研究中发挥重要的作用。Jinshan gold deposit is a superlarge-type gold deposit, and hosted in ductile shear zone, located in the well-known Cu-Au ore- concentrating district. The analysis of PGE of different rocks indicates that the rocks are deficit in PGE, the general content of PGE decrease, Pd/Pt and Pt/Ir ratio gradually decrease from carbonaceous phyllite to gold-bearing quartz vein, Pd show a strong negative correlation with Au(r=-0.9443), and Pt have no obvious correlation with Ir. The data indicate that Pd group elements and Ir elements have similar geochemistry behavior during fluid flow, and carbonaceous phyllite, ultramylonite and gold-bearing quartz vein have same origin of mass. Different rock types have similar REE patterns of slight right slope, with δEu = 0.62～0.71 and δCe =0.97～1.01. Based on results of previous work and the geological history of northeastern Jiangxi, We propose the PGE can be regarded as geochemistry tracer in the research field of fluid flow.

关 键 词：成矿物质来源 铂族元素 地球化学示踪剂 流体作用 金矿床 富集作用 

分 类 号：P618.51[天文地球—矿床学]