RESEARCH PROGRESS OF ALTYN FAULT IN WESTERN CHINA

作     者：Ge Xiaohong, Ye Huiwen, Liu Yongjiang, Liu Junlai, Pan Hongxun, Ren Shoumai (College of Earth Sciences, Changchun University of Science and Technology, Changchun 130061,China) 

出 版 物：《地学前缘》 (Earth Science Frontiers)

年 卷 期：2000年第7卷第S1期

页      面：243-244页

核心收录：

学科分类：0709[理学-地质学] 081803[工学-地质工程] 07[理学] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：TheresearchisfundedbyNSFC (No.4 9772 157) 

主　　题：reconstruction geochronology tectonic Altyn fault 

摘      要：As the northern boundary of Tibetan Plateau, the Altyn strike\|slip fault in western China has a very important implication to the tectonic division in the middle Asia continent, and has become a hot topic for the research on continental dynamics of Tibetan Plateau. During the research of our project funded by NSFC, we collected a sample of Caledonian mylonitized granite in the north of Dangjin pass and two samples of Jurassic meta\|sedimentary rocks in Qaidam gate fault\|valley and Geshi fault\|valley. The texture study shows that all samples were reformed by ductile deformation with undulating extinction and elongated quartzes. The metamorphic p\|T condition are estimated to be 350～500℃ and 150～450MPa They contain the syntectonic\|growing minerals such as white mica, chlorite, sericite and biotite etc. By dating these minerals, we obtain a group white mica 40 Ar/ 39 Ar isochronal age of 89 2～91 7Ma and a (46 6±6 4)Ma sericite 40 Ar/ 39 Ar apparent age. These data are very important to determine the strike\|slip age of Altyn *** 40 Ar/ 39 Ar age data (91～46Ma), we obtained, are reported for the first time in the researches of Altyn fault belt. The ages of 91～89Ma indicate that Altyn fault began to slip with slight metamorphism around late Jurassic. These ages are consistent with the ages of the collision between Kohistan\|Ladakh massif (northwestern India) and Eurasian continent at 102～*** suggests that the strike\|slip movement of Altyn fault should be related to the formation of the so\|called“Western tectonic joint in Nepal\|western Kunlun area. The age of 46Ma should represent the overprint age of the tectono\|thermal event during main collision between Indian and Eurasian continents along the Yarlung Zangbo River. With the continent\|continent collision of Indian and Eurasian Plates, Altyn fault underwent Multi\|phase strike\|slip events in late Paleocene—Oligocene (37～35Ma), Miocene (22～20Ma), Miocene—Pliocene (8～6Ma), Pliocene (2 5Ma) and early