东秦岭栾川铅锌银矿田辉长岩锆石SHRIMP U-Pb年龄及成矿时代  

SHRIMP zircon U-Pb age of the gabbro dyke in the Luanchuan Pb-Zn-Ag orefield,east Qinling orogen and its constraint on mineralization time

作　　者：包志伟[1] 李创举[1] 祁进平[1] 

机构地区：[1]中国科学院广州地球化学研究所成矿动力学重点实验室,广州510640

出　　处：《岩石学报》2009年第11期2951-2956,共6页Acta Petrologica Sinica

基　　金：国家重点基础研究发展计划(批准号:2006CB403504);国家自然科学基金(批准号:40672070)资助项目

摘　　要：东秦岭栾川地区是著名的钼钨和铅锌多金属矿田。矿田内铅锌银矿床的成因及其与晚中生代构造岩浆活动关系一直存在诸多争论,其症结之一就是缺少可靠的同位素定年数据。铅锌银矿床赋存于中-晚元古代浅变质碳酸盐建造,野外地质观察发现碳酸盐-硫化物脉体及细粒黄铁矿呈细脉或浸染状沿辉长岩裂隙分布。辉长岩中锆石为无色透明柱状晶体,阴极发光图像显示清晰的震荡韵律环带,SHRIMP U-Pb年龄为147.5±1.7 Ma,MSWD=1.5。根据铅锌矿脉与辉长岩穿插关系,断定成矿作用晚于辉长岩结晶年龄,即不早于147.5±1.7 Ma。Luanchuan area,located in eastern Qinling orogen,is famous for its Mo-W and Pb-Zn-Ag mineralizations.The Pb-Zn-Ag mineralization and its relationship with the intensive late Mesozoic tectonic-magmatic activities have long been a debate issue,which mostly due to lack of precise isotopic ages.The Pb-Zn-Ag deposits are mainly hosted in the Mesoproterozoic to Neoproterozoic carbonate strata,and field observation shows that the coarse-grained carbonate-sulfide veins and fine-grained pyrite occur along the fractu...

关 键 词：辉长岩 铅锌银矿 晚中生代 栾川 东秦岭 

分 类 号：P588.124[天文地球—岩石学]