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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。
The Yaoguanxian tungsten deposit in Hunan is located in the middle part of the Nanling East-West tectonic belt, the junction of the Gallong uplift belt and the Indosinian-Yanshan sag belt. There are Cambrian, Devonian, Carboniferous and Jurassic formations in the area, of which Cambrian and Devonian are the main strata containing ore. Ore bodies occur in the inner and outer contact zones of early Yanshan granite. On the basis of previous studies on geological structure, lithogeochemistry and isotopic chronology of the deposit, the author uses the isotopic dating of SHRIMP uranium-lead, rubidium-strontium and the rhenium-osmium isotope dating method, (170.7 ± 2.2) Ma (confidence 95%, n = 12, MSWD) were obtained from the granite bodies and the wolframite-quartz veins in the inner and outer contact zones of the rock mass. = 1.7). The Wollastonite-quartz vein (175.8 ± 4.1 Ma) (95% confidence level, MSWD = 0.88) was produced in the Cambrian strata in the outer contact zone of the rock mass and was produced in the contact zone The Wollastonite-quartz vein was (156 ± 3) Ma (95% confidence interval, MSWD = 0.20). The age of the molybdenite produced in the outer contact quartz vein was (170 ± 5) Ma. The results show that the Yaogangxian tungsten deposit has experienced at least two stages of mineralization, corresponding to the J1 / J2 transitional period and the J2 / J3 transitional period respectively. Deep prospecting work in the future, especially deep in the Yangmeiling Colliery, should pay attention to finding quartz vein type and skarn type ore bodies formed respectively in two periods.