西藏冈底斯西部地区印支期岩浆岩的发现及其意义  

Discovery of Indosinian Magmatic Rocks and Its Significance

作　　者：彭建华[1] 赵希良 何俊[1] 黄韶春[1] 龚臣[1] 

机构地区：[1]江西省地矿局九一五地质大队,江西南昌330002

出　　处：《东华理工大学学报（自然科学版）》2013年第S2期21-26,共6页Journal of East China University of Technology(Natural Science)

基　　金：中国地质调查局地质调查项目"西藏打加错地区4幅区调"(1212011086038)

摘　　要：对在西藏冈底斯西部措勤县打加错地区辉石角闪二长闪长岩进行了LA-ICP-MS锆石U-Pb法定年、锆石同位素组成、主量元素及微量元素测定。结果表明,辉石角闪二长闪长岩岩浆结晶年龄为(207.3±3.6)Ma,其物质来源与下地壳基性熔岩及上地幔的部分熔融有关,内构造环境为造山带,是特提斯洋在晚印支期仍在俯冲的证据。该印支晚期侵入岩是首次在南冈底斯带西侧发现,对研究冈底斯在晚印支期的构造演化提供了依据。The LA-ICP-MS zircon U-Pb statutory year,Zircon isotopic composition,major elements and trace elements of are determined. In the western Gangdisi playing a mistake Cuoqin County area pyroxene hornblende diorite two were The results showed that two pyroxene hornblende diorite magma crystallization age of( 207. 3 ± 3. 6) Ma,Its material sources and mafic lower crust and upper mantle lava partial melting,Orogenic intraplate tectonic environment,Tethys is still in the Late Triassic subduction evidence。The Late Triassic intrusive rocks is the first discovery in the South west Gangdese,The study of the late Indosinian Gangdese tectonic evolution provided。

关 键 词：锆石U-PB定年 晚印支期闪长岩 冈底斯带 西藏 

分 类 号：P588.1[天文地球—岩石学]