黑龙江东部晚三叠世A型花岗岩的厘定及其构造环境的地球化学制约  

Confirmation of Late Triassic A-type granite and their geochemical constraints on structural setting in eastern Heilongjiang

作　　者：郑全波[1,2] 汪岩[3] 张广宇[3] 金哲岩 

机构地区：[1]吉林大学地球科学学院,长春130061 [2]黑龙江地质调查研究总院齐齐哈尔分院,哈尔滨150036 [3]沈阳地质调查中心,沈阳110034

出　　处：《世界地质》2012年第3期471-478,共8页World Geology

基　　金：国家基础地质调查1:25万乌云镇;嘉荫县;太平沟幅区调成果(200313000035)

摘　　要：岩石学及元素地球化学研究结果表明,黑龙江省东部五营—汤旺河一带存在晚三叠世过铝质A型花岗岩。A型花岗岩由正长--碱长花岗岩类和碱性花岗岩组成,相当于Liegeois提出的后碰撞作用阶段的产物,标志着造山事件趋于结束,新的板内环境开始。Rb--Sr同位素测年显示其形成于晚三叠世,代表了佳木斯板块和松嫩—张广才岭板块在晚三叠世末期沿着嘉荫—牡丹江缝合带碰撞拼合后的伸展作用,标志着古亚洲洋构造域演化结束,黑龙江东部此时已经开始进入了滨太平洋构造域的板内演化阶段。The study of petrology and element geochemistry indicated that there were aluminous A-type granites during Late Triassic in the Wuying——Tangwanghe area of eastern Heilongjiang Province.The granites are composed of syenogranite-alkaline feldspar granites and alkaline granites,equivalent to the late-collision extension proposed by Liegeois,indicating the ending of orogenic event and the beginning of new interaplate environment.The whole rock Rb——Sr isochronal age shows the granites formed in Late Triassic,representing the post-orogenic extension of Jiamusi plate and Songnen——Zhangguangcai plate along with Jiayin-Mudanjiang suture zone during Late Triassic,which indicated the ending of the evolvement of Paleo-Asia Ocean structural zone,and the begining of eastern Heilongjiang into the interaplate evolution of littoral-Pacific structural zone.

关 键 词：过铝质A型花岗岩 晚三叠世 后碰撞 黑龙江省东部 

分 类 号：P588.121[天文地球—岩石学]