北祁连西段祁青构造混杂岩中的单颗粒锆石U-Pb年龄及其地质意义  

U-Pb DATING FOR SINGLE-GRINE ZIRCON OF QIQING TECTONIC MELANGE BELT IN THE WEST SECTOR OF NORTHERN QILIAN

作　　者：王建军[1] 

机构地区：[1]甘肃省地质调查院,甘肃兰州730000

出　　处：《甘肃地质》2014年第3期9-14,共6页Gansu Geology

基　　金：北祁连西段三岔口等6幅1:5万区域地质调查项目部分成果

摘　　要：在北祁连西段三岔口等6幅1∶5万区域地质调查中,对祁青构造混杂岩进行了调查研究,通过LA-ICPMS法单颗粒锆石U-Pb同位素测年,获得206Pb/238U表面加权平均年龄494±15Ma,相当于中寒武世,故将该混杂岩解体,部分归为中寒武世黑刺沟组。Petrological and geochemical characteristics as well as formation ages of the Qiqing tectonic melange belt were investigated during the regional geological survey（scale 1：50000） in Sanchakou 6 maps etc, the west sector of the northern Qilian Mountains. By LA-ICPMS isotopic age determination, getting the average age of206 Pb /238 U surface weighted 494 ±15Ma, equivalent to the Middle Cambrian. So will the Qiqing tectonic melange belt disintegration, part to Middle Cambrian Heicigou group.

关 键 词：北祁连西段 祁青构造混杂岩 单颗粒锆石U-PB年龄 中寒武世黑刺沟组 

分 类 号：P597.3[天文地球—地球化学] P588.36[天文地球—地质学]