【摘要】 湖南瑶岗仙钨矿床位于南岭东西构造带中部,加里东隆起带与印支-燕山凹陷带的交汇部位。区内出露地层有寒武系、泥盆系、石炭系和侏罗系,其中寒武系和泥盆系为含矿的主要层位。矿体赋存于燕山早期花岗岩体内外接触带。笔者在前人对矿床的地质构造、岩石地球化学以及同位素年代学等方面研究的基础上,采用SHRIMP铀-铅、铷-锶等时线和铼-锇等时线定年方法,对瑶岗仙花岗岩体及赋存于岩体内外接触带的黑钨矿-石英脉进行精确定年,获得岩体锆石SHRIMP铀-铅年龄为(170.7±2.2)Ma(置信度95%,n=12,MSWD=1.7),产于岩体外接触带寒武系地层中的黑钨矿-石英脉年龄为(175.8±4.1)Ma(置信度95%,MSWD=0.88),产于岩体内接触带的黑钨矿-石英脉年龄为(156±3)Ma(置信度95%,MSWD=0.20),产于外接触带石英脉中的辉钼矿年龄为(170±5)Ma。测定结果表明,瑶岗仙钨矿床的形成至少经历了两个成矿期,分别对应于J1/J2过渡期与J2/J3过渡期。今后的深部找矿工作尤其是杨梅岭矿段深部应该注意寻找两个时期分别形成的石英脉型和矽卡岩型矿体。更多还原

【Abstract】 The Yaogangxian tungsten deposit of Hunan province is located in the central part of the Nanling EW-direction tectonic belt,interjunction of Caledonian uplift zone and Indosinian-Yanshanian hollow zone. The strata of Cambrian,Devonian,Carboniferous and Jurassic widely spread in the area with Cambrian and Devonian as the dominant ore-bearing strata. The ore body hosted in the inside and outside contact zone of the early Yanshanian granite. On the basis of geological structure,rock geochemistry,isotope chronology and other research of the deposit,the authors used SHRIMP U-Pb,Rb-Sr and Re-Os isochrone techniques to determine the ages of rock-forming and ore-forming in the Yaogangxian mine. The Yaogangxian granite mass and wolframite-quartz vein which hosted in inside and outside of mass contact zone was tested and the SHRIMP U-Pb age,of (170.7±2.2) Ma (95% confidence,n=12,MSWD=1.7) was obtained and the age of (175.8±4.1) Ma (95% confidence,MSWD=0.88) for the wolframite-quartz vein which located in outside of mass contact zone and the age of (156±3) Ma (95% confidence,MSWD=0.20) for the wolframite-quartz vein which located in inside of mass contact zone were also obtained. While the Re-Os isochron age for molybdenite was (170±5) Ma (MSWD=0.34). The results indicate the formation of the Yaogangxian tungsten deposit undergoing at least two mineralization periods,corresponding to J1/J2 and J2/J3 transition periods respectively. Furthermore,the rock-forming and ore-forming process of the deposit is featured by multi-stage and multi-phase superimposing,and the process of ore-forming is coupling with the process of rock-forming.更多还原