云南会泽铅锌矿床粘土矿物K-Ar测年及其地质意义  

K-Ar dating of altered clay minerals from Huize Pb-Zn deposit in Yunnan Province and its geological significance

作　　者：张长青[1] 毛景文[1,2] 刘峰[3] 李厚民[1,2] 

机构地区：[1]中国地质大学 [2]中国地质科学院矿产资源研究所,北京100037 [3]中国地质科学院矿产资源研究所

出　　处：《矿床地质》2005年第3期317-324,共8页Mineral Deposits

基　　金：中国地质调查局地质调查项目(200310200002);国家重点基础研究发展规划项目(G1999043211)的资助

摘　　要：文章应用K-Ar法测得会泽铅锌矿床矿体中的蚀变粘土矿物年龄为(176.5±2.5) Ma,该年龄为成矿作用第一阶段黄铁矿形成的年龄,略早于第二阶段方铅矿、闪锌矿和方解石的形成年龄.该年龄表明这些铅锌矿床的形成与峨眉山玄武岩浆活动(251～262 Ma)有明显的时间间隔,而可能为特提斯板块向大陆俯冲期间在大陆边缘岩浆弧后伸展带形成的MVT矿床.The large-size Huize Pb-Zn deposit is a typical ore deposit in the Sichuan-Yunnan-Guizhou Pb-Zn ore district. Accurate metallogenic ages of the deposits in this district were not determined in the past. In this paper, the age of (176.5±2.5) Ma is obtained by K-Ar dating of altered clay minerals, which is the same as the age of the first-stage pyrite and is a bit older than the age of sphalerite, galena and calcite which were formed at the second stage. The data indicate that the ore-forming event of the Pb-Zn deposits is obviously later than the acti-(vity) of Emeishan basalt (251～262 Ma). The deposit is likely to be of MVT which was formed in the extension belt of the landmass margin back-arc magma when Tethyan block subducted to the landmass.

关 键 词：地球化学 K—Ar年龄 粘土矿物 成矿作用 会泽铅锌矿 云南 

分 类 号：P619.23[天文地球—矿床学] P597.1[天文地球—地质学]