投稿时间：2018-06-09
修订日期：2018-10-15
网络发布日期：2019-01-09
中文摘要:德兴斑岩铜矿田是中国东部最大的斑岩铜矿系统，一直以来，德兴铜矿的成矿过程和成因机制都是矿床学家关注的热点问题。前人在德兴铜矿的围岩蚀变、矿化期次、流体特征、成岩年代等方面取得了较为一致的认识，但其成矿时代仍争议较大。文章首次对矿田内与黄铜矿密切共生的黄铁矿进行了Re-Os同位素定年，10件样品中的4件w（Re）极低，模式年龄变化范围大，且误差较大，故不对其进行讨论；其余6件的w（Re）为10.58×10-9~102.59×10-9，普通w（Os）较低（0.0054×10-9~0.0113×10-9），w（187Os）较高（0.019×10-9~0.177×10-9），Re/Os比值较高（4406~73 422），为低含量高放射性Os成因硫化物。研究获得黄铁矿Re-Os同位素加权平均模式年龄为（165.3±2.3）Ma（MSWD=1.04）。因此，德兴铜矿的铜成矿年龄为中侏罗世，综合前人资料，德兴铜矿最可能形成于古太平洋板块俯冲的远程效应影响下的陆内伸展的地质背景，为陆内环境斑岩铜矿。
Abstract:The Dexing porphyry copper orefield is the largest porphyry Cu system in eastern China. The metallogenic process and genetic mechanism of Dexing copper mine have always been a hot issue which have aroused much interest among geologists. Previous studies have reached a consensus on the alteration, minerogenetic stages, characteristic of fluids and petrogenetic age. However, its metallogenic age remains controversial. In order to further determine its metallogenic age, the authors first carried out the Re-Os isotopic dating of pyrite. Four pyrite samples were rejected for their extremely low content of Re, wide range of model ages and large errors. The remaining six pyrite samples belong to low-level highly radiogenic (LLHR) sulfides, characterized by Re content between 10.58×10-9 and 102.59×10-9, low common Os content (0.0054×10-9~0.0113×10-9), relatively high content of 187Os (0.019×10-9~0.177×10-9) and Re/Os ratios (4406~73 422). The average Re-Os model age is (165.3±2.3) Ma (MSWD=1.04), indicating that the porphyry style Cu mineralization occurred during the Jurassic period. The Dexing copper mine was probably formed in the geological background of intracontinental extension.
文章编号：
中图分类号：P618.41
文献标志码：
基金项目:国家重点研发计划（编号：2016YFC0600206）、国家自然科学基金（编号：41772063）和中国地质调查局项目（编号：12120114034601）联合资助
引用文本：
李利,倪培,王国光,朱安冬.2018.德兴斑岩铜矿田黄铁矿Re-Os同位素定年及其地质意义[J].矿床地质,37(6):1168~1178LI Li,NI Pei,WANG GuoGuang,ZHU AnDong.2018.Re-Os isotopic dating of pyrite from Dexing porphyry copper orefield and its geological significance[J].Mineral Deposits37(6):1168~1178
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