大兴安岭北段巴升河岩体锆石U-Pb年代学及其地质意义  

ZIRCON U-Pb GEOCHRONOLOGY OF BASHENGHE PLUTON IN NORTHERN DAXINGANLING MOUNTAINS:Geological Implications

作　　者：陈会军[1] 崔天日[1] 钱程[1] 李林川[1] 陈井胜[1] 李伟[1] 吴新伟[1] 江斌[1] 司秋亮[1] 秦涛[1] 唐振[1] 张渝金[1] 郭威[1] CHEN Hui-jun;CUI Tian-ri;QIAN Cheng;LI Lin-chuan;CHEN Jing-sheng;LI Wei;WU Xin-wei;JIANG Bin;SI Qiu-liang;QIN Tao;TANG Zhen;ZHANG Yu-jin;GUO Wei(Shenyang Center of Geolopctd Survey,CGS,Shenyang 110034,China)

机构地区：[1]中国地质调查局沈阳地质调查中心

出　　处：《地质与资源》2019年第5期405-412,共8页Geology and Resources

基　　金：中国地质调查局“辽东-吉中地区区域地质调查”（DD20190042）、“东北地区花岗岩地质编图”（1212011121084）、“东北地区重大岩浆事件及其成矿作用和构造背景综合研究”（12120114085601）、“内蒙古1∶5万索格图等4幅区域地质调查”（DD20190039-04）

摘　　要：大兴安岭北段扎兰屯地区巴升河岩体由碱长花岗岩组成.采用LA-ICP-MS方法对碱长花岗岩开展锆石U-Pb测年,结果为297.8±3.6 Ma,岩体形成于早二叠世.该岩体4个样品的全岩地球化学等特征显示:巴升河岩体中碱长花岗岩具有富Si、高K、富碱的特征,属于弱过铝质钾玄岩系列,同时,样品∑REE偏高,Eu负异常明显,富集大离子亲石元素,具有A型花岗岩特征,综合前人研究成果及同位素年代学特征,认为兴安地块与松嫩地块拼合的时间早于298 Ma.The Bashenghe pluton in Zhalanlun area of northern Daxinganling Mountains is composed of alkali-feldspar granite.The zircon LA-ICP-MS U-Pb dating yields the weighted mean age of 297.8±3.6 Ma.indicating the pluton was formed in the Eady Permian.The whole rock geochemistry of 4 samples shows that the alkali-feldspar granite is characterized by rich Si.high K and rich alkali,belonging to weak peraluminous shoshonite series.The characteristics of high Z REE.obvious negative Eu anomalies and enrichment of LILEs are properties of A-type granite.Combined with previous research results and isotopic chronology,it is concluded that the convergence of Xing’an massif and Songnen massif occurred before 298 Ma.

关 键 词：巴升河岩体 碱长花岗岩 锆石U-PB测年 兴安地块与松嫩地块拼合 大兴安岭北段 

分 类 号：P597[天文地球—地球化学] P588.12[天文地球—地质学]