SHRIMP锆石年代学对西藏玉龙斑岩铜矿成矿年龄的制约  

Constraints to the mineralization age of the Yulong porphyry copper deposit from SHRIMP U-Pb zircon data in Tibet.

作　　者：郭利果[1] 刘玉平[1] 徐伟[1] 张兴春[1] 秦克章[2] 李铁胜[2] 石玉若[3] 

机构地区：[1]中国科学院地球化学研究所矿床地球化学重点实验室 [2]中国科学院地质与地球物理研究所,北京100029 [3]中国地质科学院北京离子探针中心,北京100037

出　　处：《岩石学报》2006年第4期1009-1016,共8页Acta Petrologica Sinica

基　　金：国家重点基础研究发展规划项目(编号2002CB412601);中国科学院矿床地球化学重点实验室联合资助。

摘　　要：锆石SHRIMP U-Pb定年结果表明,玉龙岩体侵入时限至少为2．6Ma,其中成矿前石英二长斑岩的年龄为43．6±0．8Ma,成矿期黑云母二长花岗斑岩的年龄为41．0Ma±1．0Ma,代表了两幕较大的岩浆活动。玉龙斑岩铜矿主体成矿年龄约为40Ma,长时限多期幕式岩浆侵入和成矿期物理化学条件的剧变,是形成玉龙超大型斑岩铜矿的主要原因。玉龙斑岩铜矿与金沙江-红河成矿带众多新生代斑岩铜矿一样,属于印度-亚欧大陆45Ma陆陆主体碰撞之后第一次大规模应力释放的产物。The SHRIMP U-Pb data has shown that the intruding process of the Yulong pluton was lasted at least 2. 6Ma. There were two large intruding episodes, the age of 43.6 ± 0. 8Ma for the pre-fmineralisation quartz-feldspars porphyry and the age of 41.0 ± 1.0Ma for the ore-fhosted biotite-feldspars porphyry. The main mineralization age of the Yulong porphyry copper deposit was around 40Ma. It is believed that long and episodic magmatism, and acute changes of temperature and pressure during ore-forming process, were the important cause of forming the super-large Yulong porphyry copper deposit. The Yulong porphyry copper deposit, like as the Neozoic porphyry copper deposit in the Jinshajiang-Honghe metallogenic belt, is result of the first large-scale stress release after the main collision between Indian plate and Eurasia plate at 45Ma.

关 键 词：SHRIMP年龄 锆石 斑岩铜矿 玉龙 西藏 

分 类 号：P597.3[天文地球—地球化学] P618.41[天文地球—地质学]