投稿时间：2022-01-07
修订日期：2022-08-25
网络发布日期：2022-11-08
中文摘要: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。
中文关键词: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
Abstract: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 ana-lyses 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.
keywords:geochemistry dacite porphyry detrital zircon U-Pb age chalcopyrite Re-Os age Dabaoshan Nanling
文章编号：
中图分类号：
文献标志码：
基金项目:本文得到中国地质调查局中国矿产地质志项目（编号：DD20160346、DD20190379、DD20190173、DD20190379-99）和东华理工大学博士启动基金（编号：1410000495）共同资助
引用文本：
赵晨辉,王成辉,赵如意,刘武生,张熊,蒋金昌,李挺杰.2022.广东大宝山火山岩和斑岩铜矿年代学研究及其地质意义[J].矿床地质,41(5):1042~1056ZHAO ChenHui,WANG ChengHui,ZHAO RuYi,LIU WuSheng,ZHANG Xiong,JIANG JinChang,LI TingJie.2022.Geochronology and geological implications of volcanic rock and porphyry copper deposit in Dabaoshan, Guangdong Province[J].Mineral Deposits41(5):1042~1056
图/表
