西昆仑康西瓦北侧早古生代角闪闪长岩、英云闪长岩的地质特征及其锆石SHRIMP U-Pb测年

Geological characteristics of Early Paleozoic amphibolite and tonalite in northern Kangxiwar, West Kunlun, China and their zircon SHRIMP U-Pb dating

西昆仑康西瓦北侧蒙古包—普守一带的早古生代俯冲-碰撞型角闪闪长岩、英云闪长岩和黑云二长花岗岩,是开展1∶25万康西瓦幅等4幅区域地质调查项目时发现的。重点对蒙古包早古生代俯冲型角闪闪长岩、英云闪长岩的岩石学、岩石地球化学特征及锆石同位素年代学进行了综合研究,获得了锆石SHRIMPU-Pb年龄440.5Ma±4.6Ma,其形成时代为晚奥陶世。该成果为进一步深入研究西昆仑造山带的地质构造演化提供了新的实际资料。

Early Paleozoic subduction-coUision type amphibolite, tonalite and biotite monzogranite in the Menggubao-Pushou area in northern Kangxiwar, West Kunlun, were found during regional geological surveys of the 1：250000 Kangxiwar Sheet and other three sheets of the same scale. The focus was on the integrated study of the petrological and geochemical characteristics and zircon isotope chronology of Early Paleozoic subducttion-type amphibolite and tonalite in Menggubao. Their zircon SHR/MP U-Pb age is 440.5±4.6 Ma, indicating a Late Ordovician age for their formation. The study results provide new information for the further study of the tectonic evolution of the West Kunlun orogenic belt.