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.%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.
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