云南巧家东坪铅锌矿床原生晕特征与找矿潜力  

Prospecting Potential and Primary Halo Characteristics of Dongping Pb-Zn Deposit in Qiaojia County,Yunnan

作　　者：明添学 唐忠 李永平 罗建宏 李蓉 薛戈 陈雷 Ming Tianxue;Tang Zhong;Li Yongping;Luo Jianhong;Li Rong;Xue Ge;Chen Lei(Institute of Yunnan Geology Survey,Kunming 650051,China;Key Laboratory of Sanjiang Metallogeny and Resources Exploration and Utilization, Ministry of Land and Resources,Kunming 650051,China)

机构地区：[1]云南省地质调查院,昆明650051 [2]国土资源部三江成矿作用及资源勘查利用重点实验室,昆明650051

出　　处：《吉林大学学报（地球科学版）》2018年第5期1394-1404,共11页Journal of Jilin University：Earth Science Edition

基　　金：中国地质调查局项目(12120114013901);国家重点基础研究发展计划("973"计划)项目(2015CB452605)~~

摘　　要：云南省巧家县东坪铅锌矿床大地构造位置处于扬子地台西南缘,是滇东北地区一个典型的铅锌矿床。矿体赋存于震旦系灯影组白云岩中,呈脉状、似层状,并受断裂构造和Si/Ca面控制,矿石矿物以方铅矿、闪锌矿为主,近矿围岩蚀变有硅化、白云石化、黄铁矿化。硫、铅同位素分析显示,成矿流体的硫源主要是赋矿地层中的海水硫酸盐经热化学还原作用而成,铅来自壳源。岩石原生晕特征显示:成矿过程具有多阶段叠加,早期成矿作用以铅为主,并有微弱的锌矿化,而后受铅矿化强烈的叠加改造作用;钻孔S5ZK001→ZK001→S4ZK001近矿晕元素Pb、Zn组分从南西到北东向呈由浅部到深部的分布规律;钻孔ZK001→ZK701-1→ZK1701→ZK3901亦为由浅部到深部的分布规律;以ZK001为中心,向南东、北东矿体埋深加大,在北东部(S4ZK001)及南东部(ZK3901)深部还具有一定的找矿潜力。The Dongping Pb Zn deposit,located in the southwest edge of Yangtze platform in the northeastern Yunnan,is a representative deposit with low research and exploitation.In the shape of vein and layer,the orebodies mainly occur in dolomites of the Sinian Dengying Formation,and are obviously controlled by the fractures and their Si/Ca surfaces.The major ore minerals are galena and sphalerite.The wall-rock alteration includes silicification,dolomitization,pyritization.Theδ34 S‰value of the sulfides implies that the sulfur was likely derived from seawater and went through a series of thermal chemical sulfate reduction(TSR).The lead isotopic composition of sulfides indicates an extremely radiogenic feature similar to that of the crust.The mineralization is characterized by multiple stages of ore-forming evolution and overlapped by late fluids.A great amounts of lead were formed in the major metallogenic stage with a little zinc formed in the early stage.The near halo Pb,Zn components in borehole S5ZK001→ZK001→S4ZK001 are distributed from shallow to deep from the south-west to the north-east,the same as with those of the borehole ZK001→ZK701 1→ZK1701→ZK3901.With ZK001 as the center,the ore bodies have a bigger buried depth in the south-east and north-east parts of it.There is a certain prospecting potential in the deep part of the north-east(S4ZK001)and the south-east(ZK3901).

关 键 词：东坪铅锌矿床 地质特征 原生晕 找矿潜力 

分 类 号：P588.1[天文地球—岩石学] P597.3[天文地球—地质学]