湖南邓阜仙钨矿辉钼矿铼-锇同位素定年及硫同位素地球化学研究  

Re-Os geochronology and S isotope geochemistry of Dengfuxian tungsten deposit,Hunan Province,China

作　　者：蔡杨[1] 马东升[1] 陆建军[1] 黄卉[2] 章荣清[1] 屈文俊[3] 

机构地区：[1]内生金属矿床成矿机制研究国家重点实验室,南京大学地球科学与工程学院,南京210093 [2]广东省地质过程与矿产资源探查重点实验室,中山大学地球科学系,广州510275 [3]国家地质实验测试中心,北京100037

出　　处：《岩石学报》2012年第12期3798-3808,共11页Acta Petrologica Sinica

基　　金：国家重点基础研究发展计划项目(2012CB416702);中国地质调查局调查项目(1212011085407)联合资助

摘　　要：邓阜仙钨矿是湘东南地区一个重要的钨矿床。本文对邓阜仙钨矿中的辉钼矿进行Re-Os同位素测年,显示辉钼矿的Re-Os同位素模式年龄范围为149.2±2.1Ma～156.9±2.2Ma,加权平均年龄为152.4±3.3Ma,对应的Re-Os等时线年龄为150.5±5.2Ma,与邓阜仙燕山期二云母花岗岩的锆石LA-ICP-MSU-Pb年龄(154.4±2.2Ma)接近,指示邓阜仙钨矿床与区内二云母花岗岩具有密切的成因关系。辉钼矿Re含量为2.927×10-9～98.13×10-9,表明成矿物质具有壳源的特征。硫化物δ34S值介于-1.36‰～+0.61‰之间,说明成矿物质硫源主要来自于燕山期重熔型二云母花岗岩。邓阜仙钨矿的成岩成矿作用与南岭地区大规模的钨锡多金属成矿作用在时间上一致,具有统一的地球动力学背景,形成于区域地壳拉张减薄的动力学环境。Dengfuxian tungsten deposit is an important deposit in Southeast Hunan Province,South China.Direct Re-Os dating of molybdenites in Dengfuxian tungsten deposit has been carried out,in order to restrict the age of mineralization.The results show that Re-Os model ages range from 149.2±2.1Ma to 156.9±2.2Ma,with an average age of 152.4±3.3Ma.All the Re-Os data define an isochron with an age of 150.5±5.2Ma,consistent with zircon U-Pb age（154.4±2.2Ma） of the Dengfuxian two-mica granite,indicating that the mineralization of the Dengfuxian tungsten deposit is genetically related to the two-mica granite.The Re contents of molybdenite range from 2.927×10^-9 to 98.13×10^-9,indicating that ore-forming material might have the characteristics of crustal source.The δ34S values of sulfide range from-1.36‰ to ＋0.61‰,implying that ore-forming material might come from the Yanshanian crust-remelting type granites.The rock-forming and ore-forming processes of Dengfuxian tungsten deposit are under a geodynamic setting of lithospheric thinning and extension,consistent with the large-scale tungsten-tin polymetallic mineralization（150~160Ma） in the Nanling Range,South China.

关 键 词：辉钼矿Re-Os测年 S同位素 邓阜仙钨矿 湖南 

分 类 号：P595[天文地球—地球化学] P597.3[天文地球—地质学]