【摘要】 文章采用高分辨率、高灵敏度离子探针(SHRIMP)和Rb-Sr等时线定年技术,对新疆伊吾琼河坝地区的云英山斑岩铜矿和淖毛湖北山金矿床的岩体和矿体进行了年代学研究,获得云英山斑岩铜矿区内斜长花岗斑岩体SHRIMP锆石U-Pb年龄为(411.7±7.1)Ma(95%置信度,MSWD=3.0),该矿床的含矿石英脉石英矿物Rb-Sr等时线年龄为(357±15)Ma(95%置信度,MSWD=0.16);淖毛湖北山金矿含矿石英脉中石英矿物Rb-Sr等时线年龄为(346±10)Ma(95%置信度,MSWD=0.19)。测定结果显示,该区斑岩型铜矿和破碎带蚀变岩型金矿的形成时间为晚泥盆世—早石炭世,表明云英山式斑岩型铜金矿和淖毛湖式金矿成矿作用与泥盆纪—石炭纪汇聚阶段的火山-次火山岩浆活动有关,也意味着在琼河坝地区具有寻找与火山作用有关的铜、金多金属矿的潜力。更多还原

【Abstract】 Chronological studies of rock bodies and ore bodies in the Yunyingshan porphyry copper deposit and the Beishan gold deposit of Naomaohu district in Qiongheba area,Yiwu of Xinjiang,were performed by SHRIMP and Rb-Sr dating in this paper. The dating data obtained show that the SHRIMP U-Pb age of zircon from plagio-granite porphyry in the Yunyingshan porphyry copper deposit is (412±7) Ma (with 95% of credibility,MSWD=3.0),and Rb-Sr isochron age of quartz from ore-bearing quartz vein is (357±15) Ma (with 95% of credibility,MSWD=0.16),whereas Rb-Sr isochron age of quartz from ore-bearing quartz vein in the Beishan gold deposit of Naomaohu is (346±10) Ma (with 95% of credibility,MSWD=0.19). The above ages indicate that porphyry copper deposits and gold deposits of the fracture zone altered rock type were formed in Late Devonian and Early Carboniferous. Mineralizations of porphyry copper-gold deposits of Yunyingshan style and gold deposits of Naomaohu style were related to volcanic and sub-volcanic magmatic activities during the convergent stage of Devonian-Carboniferous period. It is also held that it is promising to explore copper and gold polymetallic deposits in Qiongheba area.更多还原