新疆博格达西段石英二长岩锆石SHRIMP U-Pb测年及地质意义  

SHRIMP Zircon U-Pb Age of Quartz Monzonite in the West of Bogda Mountain, Xinjiang, China, and Its Geological Significance

作　　者：李平[1] 刘伟 朱志新[1,3] 陈川[1] 陈邦学[1] 靳刘圆[1] 

机构地区：[1]新疆大学地质与矿业工程学院,新疆乌鲁木齐830007 [2]新疆第二区域地质调查大队,新疆昌吉831100 [3]新疆地质调查院,新疆乌鲁木齐830000

出　　处：《新疆大学学报（自然科学版）》2013年第4期476-481,共6页Journal of Xinjiang University(Natural Science Edition)

基　　金：十二五科技支撑计划重点项目"博格达-哈尔里克成矿带铜-金成矿条件研究及靶区评价"(2011BAB06B04-2);新疆中亚造山带大陆动力学与成矿预测实验室开放课题(XJDX1102-2011-04);新疆天山牧场1:5万区域地质调查项目(1212011120475)

摘　　要：新疆博格达西段三个山一带地层被原1:20万区调厘定为下二叠统红雁池组(P1hy).通过对区内侵入该地层的石英二长岩体SHRIMP锆石U-Pb精确测年获得206Pb/238U加权平均年龄为331.9±2.0Ma(MSWD=0.37).结合近年来区域地质调查过程中早石炭世珊瑚化石的发现,将围岩重新厘定为下石炭统七角井组(C1qj),并初步认为该岩体年龄代表了博格达石炭纪裂谷由拉张快速转入碰撞阶段的初始侵入活动,从而为重新认识博格达造山带西段石炭纪的构造演化提供佐证.The stratigraphy of Sangeshan area in west of Bogda in Xinjiang was set to the Lower Permian Hongyanchi group （Plhy） by 1：200 000 regional surveys. The 2~6pb/23SU weighted average age of quartz monzonite which invaded that group is 331.9 ：i= 2.0Ma （MSWD = 0.37） through zircon SHRIMP U-Pb dating. And combined with the discovery of coral fossils in Early Carboniferous in the process of Regional Geological Investigation in recent years, the wall-rock is re-determined as the Lower Carboniferous Qijiaojing group （C1qj）. So the age maybe represent the initial intrusive activity during tension quickly transferred to the collision stage of Bogda Carboniferous rift. So it could provide evidence for re-understanding the tectonic evolution of the Carboniferous Bogda orogenic belt.

关 键 词：博格达西段 七角井组 石英二长岩 SHRIMP锆石U—Pb 

分 类 号：P597[天文地球—地球化学]