内蒙古莲花山铜矿区花岗闪长斑岩LA-ICP-MS锆石U-Pb年龄  

LA-ICP-MS zircon U-Pb dating of granodiorite porphyry in the Lianhuashan copper deposit of Inner Mongolia and its geological implications

作　　者：王忠禹[1] 孙景贵[1] 白令安[2] 柴鹏 古阿雷[1] 赵克强[1] 李玉洁[3] 

机构地区：[1]吉林大学地球科学学院,吉林长春130061 [2]桂林理工大学地球科学学院,广西桂林541004 [3]吉林农业大学生命科学学院,吉林长春130000

出　　处：《地质通报》2014年第9期1320-1325,共6页Geological Bulletin of China

基　　金：国家自然科学基金项目(批准号:40772052;41172072)

摘　　要：为了精确厘定莲花山铜矿的成矿时代,在前人研究的基础上,开展了与成矿关系密切的花岗闪长斑岩锆石U-Pb定年测定。实验结果共获得4组年龄数据,第1组有1个锆石,^206Pb/^238U年龄为343Ma±2Ma;第2组1个锆石,^206Pb/^238U年龄为264Ma±2Ma;第3组有1个锆石,^206Pb/^238U年龄为256Ma±2Ma;第4组有17个锆石,^206Pb/^238U年龄在240～249Ma之间,^206Pb/^238U年龄加权平均值为246.4Ma±1.2Ma（N=17）。结合所测锆石的CL图像特征,确定花岗闪长斑岩就位发生在晚二叠世—早三叠世。On the basis of previous studies,this paper carried out zircon U-Pb dating for mineralization-associated granodiorite porphyry to further study its metallogenic epoch.Four groups of ages were obtained.The first group contains one zircon with ^206Pb/^238 U age of 343Ma±2Ma;the second group contains one zircon with ^206Pb/^238 U age of 264Ma±2Ma;the third group contains one zircon with ^206Pb/^238 U age of 256Ma±2Ma;the fourth group comprises 17 zircons,whose ^206Pb/^238 U ages vary from 240 Ma to 249 Ma,with a weighted mean ^206Pb/^238 U age of 246.4Ma±1.2Ma（N=17）.In conjunction with characteristics of CL imaging,the authors hold that the emplacement of granodiorite porphyry occurred between the Late Permian and Early Triassic.

关 键 词：花岗闪长斑岩 LA-ICP-MS锆石U-PB定年 成岩成矿环境 莲花山铜矿 大兴安岭 

分 类 号：P588.121[天文地球—岩石学] P597.3[天文地球—地质学]