广东大宝山火山岩和斑岩铜矿年代学研究及其地质意义  

Geochronology and geological implications of volcanic rock and porphyry copper deposit in Dabaoshan,Guangdong Province

作　　者：赵晨辉 王成辉[1] 赵如意 刘武生 张熊[3] 蒋金昌 李挺杰 ZHAO ChenHui;WANG ChengHui;ZHAO RuYi;LIU WuSheng;ZHANG Xiong;JIANG JinChang;LI TingJie(MNR Key Laboratory of Metallogeny and Mineral Resource Assessment,Institute of Mineral Resources,CAGS,Beijing 100037,China;State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,Jiangxi,China;Guangdong Province Dabaoshan Mining Co.,LTD,Shaoguan 512127,Guangdong,China)

机构地区：[1]中国地质科学院矿产资源研究所自然资源部成矿作用与资源评价重点实验室,北京100037 [2]东华理工大学核资源与环境国家重点实验室,江西南昌330013 [3]广东省大宝山矿业有限公司,广东韶关512127

出　　处：《矿床地质》2022年第5期1042-1056,共15页Mineral Deposits

基　　金：中国地质调查局中国矿产地质志项目(编号:DD20160346、DD20190379、DD20190173、DD20190379-99);东华理工大学博士启动基金(编号:1410000495)共同资助。

摘　　要：广东大宝山矿床是南岭成矿带最重要的铜多金属矿床,近年来在矿区英安斑岩中新发现厚大的铜硫矿体。英安斑岩作为赋矿围岩,对其形成时代长期存在志留纪和侏罗纪之争,而新发现铜矿体的矿化时代也尚未得到精确限定。文章对英安斑岩中砂岩捕掳体开展了锆石LA-ICP-MS U-Pb年龄测定,结果显示存在5个晚于泥盆纪的U-Pb年龄(231 Ma、274 Ma、310 Ma、324 Ma和362 Ma),表明大宝山英安斑岩的形成时间晚于泥盆纪。同时,对英安斑岩中细脉状黄铜矿进行了Re-Os同位素测试,等时线年龄为(188±12)Ma,表明铜矿化发生在早侏罗世。成岩成矿时代与野外地质事实相结合,指示矿区北西方向具有良好的找矿潜力。The Dabaoshan is the most important copper polymetallic deposit in the Nanling metallogenic belt.In recent years,thick copper-sulfur ore bodies have been discovered in dacite porphyry in the mining area.However,dacite porphyry is the ore-bearing wall-rock,and the rock-forming age has long been disputed in the Silurian or Jurassic,and the timing of newly discovered copper mineralization has not been precisely defined.LA-ICP-MS U-Pb analyses of zircons from the sandstone xenolith in the dacite porphyry was carried out,and the rock-forming time of the dacite porphyry was explored.The results showed that there are 5 U-Pb ages(231 Ma、274 Ma、310 Ma、324 Ma and 362 Ma)younger than the Devonian indicating that the Dabaoshan dacite porphyry was formed later than the Devonian.The Re-Os isotope test was carried out on the chalcopyrite which was collected from the sulfide vein in the dacite porphyry,and the isochron age was(188±12) Ma,indicating that the copper mineralization occurred in the Early Jurassic.The combination of rock-forming and ore-forming ages and field geological facts indicate that there is good metallogenic potential in the northwest part of the mining area.

关 键 词：地球化学 英安斑岩 碎屑锆石U-PB年龄 黄铜矿Re-Os年龄 大宝山 南岭 

分 类 号：P618.41[天文地球—矿床学]