甘肃北山地区公婆泉铜矿区岩体年龄及其地质意义  

Isotopic age of rock mass in Gongpoquan mining area in Beishan of Gansu and its geological significance

作　　者：吕昶良 杨富强 罗家书 马文富 刘文勋 石伟民 LYU Changliang;YANG Fuqiang;LUO Jiashu;MA Wenfu;LIU Wenxun;SHI Weimin(Geophysical Survey Institute of Guangxi Zhuang Autonomous Region,Liuzhou 545005,Guangxi,China;China-ASEAN Geosciences Cooperation Center,Nanning 530023,Guangxi,China)

机构地区：[1]广西壮族自治区地球物理勘察院,广西柳州545005 [2]中国-东盟地学合作中心(南宁),广西南宁530023

出　　处：《矿产与地质》2021年第1期83-89,共7页Mineral Resources and Geology

基　　金：广西壮族自治区地质矿产勘查开发局“广西关键矿产资源深部勘查人才小高地项目”(2020年度)资助。

摘　　要：为更好地分析甘肃北山地区公婆泉铜矿的成矿时代及成矿过程,对公婆泉铜矿英安斑岩、花岗闪长斑岩进行了LA-ICP-MS锆石U-Pb定年。结果显示,英安斑岩形成于(431.0±8.8)Ma,而花岗闪长斑岩形成于(439.6±7.1)Ma。总结前人的研究成果,认为公婆泉铜矿存在至少两期成矿事件,早期为斑岩成矿,形成于440~430 Ma;晚期为热液叠加,与韧性剪切作用密切相关,形成于372~336 Ma。认为公婆泉—月牙山地体为岛弧带,公婆泉铜矿形成于岛弧环境。In order to better understand the mineralization age and process of Gongpoquan copper deposit in Beishan area,Gansu,LA-ICP-MS zircon U-Pb dating analysis is caaried out for dacite porphyry and granodiorite porphyry in the mining area.The result indicates that the isotopic ages of dacite porphyry and granodiorite porphyry are(431.0±8.8)Ma and(439.6±7.1)Ma,respectively.According to the previous research result,it is considered that there are at least two mineralization stages in Gongpoquan Cu deposit.The first stage is characterized by porphyry mineralization at 440-430 Ma.The second stage is superimposed by the hydrothermal mineralization which is closely related to the ductile shear process at 372-336 Ma.It is further proposed that Gongpoquan-Yueyashan terrane is an island arc belt,and that Gongpoquan Cu deposit is formed in the island arc environment.

关 键 词：公婆泉铜矿 英安斑岩 花岗闪长斑岩 甘肃北山 

分 类 号：P618.41[天文地球—矿床学] P597[天文地球—地质学]