青海东昆仑哈日扎多金属矿区构造活动的锆石裂变径迹定年分析  

Zircon Fission Track Dating Evidence for Tectonic Events in the Hariza Polymetallic Ore District,Eastern Kunlun Mountains,Qinghai-Tibet Plateau

作　　者：田承盛 张爱奎[2,3] 袁万明[2] 冯云磊 曹建辉[2] 张丽婷[2] 程学芹 陈小宁[2] 段宏伟[2] 王威[2] 郝娜娜[2] 马忠元 

机构地区：[1]青海省地质调查局,青海西宁810012 [2]中国地质大学,北京100083 [3]青海省第三地质矿产勘查院,青海西宁810029

出　　处：《地质与勘探》2014年第5期833-839,共7页Geology and Exploration

基　　金：中国地质调查局地质调查工作项目(基2011-03-04-06);青海省地质调查局项目(青地调勘2013-103);国家自然科学基金项目(41172088;40872141)联合资助

摘　　要：青海省哈日扎多金属矿区位于东昆仑东段,属东昆中多旋回岩浆弧带,是新的矿产勘查基地,成矿作用主要受NE和NW向两组构造蚀变带控制。本文通过不同类型样品的锆石裂变径迹定年分析,探讨区内的构造活动。所获得的10个样品年龄为116~204 Ma,并由3个组年龄构成,即204~181 Ma,142~168 Ma和116~120 Ma。第1组年龄204~181 Ma反映印支晚期三叠纪末羌塘地块与昆仑地块碰撞的地质事件及其时限;后两组年龄主要是晚侏罗世~早白垩世冈底斯地体向北与羌塘地体碰撞汇聚的响应,活动时限为168~116 Ma。第2和3组年龄同时表明本区燕山期构造活动存在强度差异,即有两个强作用期。同时,3组年龄也揭示本区具有多期次成矿活动。The Hariza polymetallic ore district,located in eastern section of East Kunlun Mountains,is a new base of mineral resource exploration,where mineralization is controlled by both NE and NW trending fault zones. This paper reveals the tectonic events based on zircon fission track dating for various samples in the ore district. A total of 10 zircon fission track dating results are achieved. They rang from 204 Ma to 116 Ma and are composed of three age groups of 204 ~ 181 Ma,142 ~ 168 Ma and 116 ~ 120 Ma. The first age group of 204 ~ 181 Ma reflects collision between Qiangtang Block and Kunlun Block in late Triassic and its time limit. The later two age groups respond to impact between Gangdese Block and Qiangtang Block in late Jurassicearly Cretaceous with time limit of 168 ~ 116 Ma. Meanwhile,the second and third age groups indicate two periods of tectonic events in Jurassic-early Cretaceous. The 3 age groups also coincide with multi-periods of metallogeneses.

关 键 词：构造活动 裂变径迹 锆石年龄 东昆仑 青海 

分 类 号：P597.3[天文地球—地球化学] P618.2[天文地球—地质学]