碰撞阶段 meaning in English

encounter stage

By having conducted 40ar - 39ar dating of 35 samples and sm - nd dating of 19 samples from the linzizhong volcanic rocks , the post - collision volcanic rocks and a granite dike and the yarlung zangpo ophilite , the dissertation provides significant new data and results for optimizing the time framework of tectonic - magmatic event s of this region . according to isotopic dating of 9 samples , 12 experiments survey in the main trunk profile , the eruption age of the linzizhong volcanic rock in the linzhou basin has been determined as 54 - 64ma
本论文通过35个样品的~ ( 40 ) ar - ~ ( 39 ) ar及19个样品的sm - nd同位素测年，获得了关于俯冲?碰撞阶段形成的林子宗火山岩、后碰撞火山岩与花岗岩及雅鲁藏布蛇绿岩的同位素年龄数据，为完善研究区构造?岩浆事件的时间格架提供了新的资料与成果。