博格达西段三个山石英闪长岩体地球化学特征、年代学及地质意义  

Geochemical Characteristics, Geochronology and its Geological Significance of Quartz Diorite in Sangeshan Area, West of Bogda, Xinjiang

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

机构地区：[1]新疆大学新疆中亚造山带大陆动力学与成矿预测实验室,新疆乌鲁木齐830047 [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：《新疆地质》2013年第3期162-166,共5页Xinjiang Geology

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)共同资助;新疆地矿局第二区域地质调查大队达坂城项目;天山牧场项目

摘　　要：三个山石英闪长岩体位于新疆博格达造山带西段,侵位于下石炭统七角井组中,岩石地球化学数据表明岩体具壳幔岩浆混合地球化学特征,初步认为该岩体早期通过幔源岩浆分离结晶,晚期大量壳源物质加入冷却形成。通过SHRIMP锆石U-Pb测年获得该岩体206Pb/238U加权平均年龄为(333.5±2.2)Ma(MSWD=0.26),其年龄可能代表了博格达西段石炭纪由拉张过程转入碰撞造山阶段的初始侵入活动,也是首次在该地区识别出早石炭世的岩浆活动,从而为重新认识博格达造山带西段石炭纪构造演化提供佐证。The quartz diorite located in Sangeshan area, the west of Bogda orogenic belt, in Xinjiang, which intruded in the Lower Carboniferous Qijiaojing Formation. The geochemical datas show that the rock has geochemical characteris- tics of the crust-mantle magma mixed, and preliminary view that the rock early derived from mantle magma fractional crystallization, late a lot of the crust source material added to tbml it. The ^206Pb/^238U weighted average age of the rock is （333.5±2.2）Ma （MSWD=0.26） by SHRIMP zircon U-Pb dating, this age maybe represent the initial invasive activity dur- ing the Carboniferous Bogda transferred stretching process to the collisional orogenic stage, and Early Carboniferous magmatic activity is identified in the region for the first time, and it could provide evidence for re-understanding the tec- tonic evolution of the Bogda orogenic belt of Carboniferous.

关 键 词：博格达 石英闪长岩 地球化学特征 SHRIMP U—Pb测年 

分 类 号：P588.122[天文地球—岩石学]