中天山南缘乌瓦门地区蛇绿混杂岩中前寒武花岗质岩块年代的厘定及其构造意义  

Zircon U-Pb dating age and its tectonic significance of granitic rocks in the Wuwamen ophiolite melange in Zhongtian Mountain,Xinjiang

作　　者：王梦超 刘磊[1] 刘希军[1] 王葆华[1] 龚小晗[2] 张治国 谭震江 WANG Mengchao;LIU Lei;LIU Xijun;WANG Baohua;GONG Xiaohan;ZHANG Zhiguo;TAN Zhenjiang(Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration & Guangxi Nonferrous Metal Concealment Deposits Exploration and Material Development Collaborative Innovation Center, Guilin University of Technology,Guilin 541006,Guangxi,China;School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083 China)

机构地区：[1]桂林理工大学广西隐伏金属矿产勘查重点实验室&广西有色金属隐伏矿床勘查及材料开发协同创新中心,广西桂林541006 [2]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《矿产与地质》2019年第2期296-303,共8页Mineral Resources and Geology

基　　金：国家自然科学基金(编号:41772059)资助

摘　　要：中天山乌瓦门地区蛇绿混杂岩中出露了较多的花岗质岩块,但对于其来源、属性、形成时代及其构造意义,尚缺乏系统的厘定。岩相学表明,乌瓦门地区构造混杂岩中的花岗质岩具有区域变质成因的花岗质岩石特点,经定年测试分析乌瓦门混杂岩中变质花岗质岩中的锆石年龄为(2343±11)Ma和(1702±22)Ma,进一步表明它们并不是与蛇绿岩形成过程中有成因联系的斜长花岗岩。通过对比中天山地块和塔里木地块的岩相学、地层学以及岩浆事件记录,进一步支持中天山地块存在前寒武纪基底及其与塔里木克拉通的构造亲缘性。There are many occurrence granitic rocks in the Wuwamen ophiolite melange in Zhongtianshan,Xinjiang,but their origin,formation age and tectonic implication still remain unknown.Petrographic analysis of the granitic rocks indicated that they have the characteristics of rocks formed by regional metamorphism.Zircon U-Pb dating analysis were carried out on the granitic rocks from the melange in the Wuwamen area,which gives concordant zircon U-Pb ages at ac.(2343±11)Ma and(1702±22)Ma.These Paleoproterozoic ages suggests that there are no genetic relations between the granite blocks and the Wuwamen ophiolites.By comparing the stratigraphy and petrography of the Zhongtianshan arc terrane and the northern Tarim block,further supported the existence of Precambrian basement in the Zhongtianshan terrane and its tectonic affinities with the Tarim craton.

关 键 词：蛇绿岩混杂岩 变质花岗岩 前寒武基底 锆石U-Pb年龄 乌瓦门地区 中天山 

分 类 号：P588.121[天文地球—岩石学]