LA-ICP-MS Zircon U-Pb Dating of Garnet-Bearing Muscovite-Biotite Plagioclase Gneiss in Western Kangxiwar Fault of Western Kunlun and Its Tectonic Significance

详细信息   

• 责任者：Kang Lei (X’an Institute of Geology and Mineral Resources ; China Geological Survey ; Xi’an 710054 ; China) ; Xiao Peixi
• 刊名：Geological Bulletin of China
• 出版年：2012
• 卷期：31(8)
• 关键词：片麻岩 ; gneisses ; 铀—铅计时 ; U-Pb dating ; 昆仑山 ; Kunlun Mountains
• 页码：p.1244-1250
• 图表：3 illus., 2 tables, 37 refs.
• 分类号：0802
• issnNo：ISSN1671-2552
• isbnNo：CN11-4648/P

摘要

According to cathodoluminescence （CL） images and Th, U, REE characteristics, the zircons can be classified into magmatic zircons and metamorphic-hydrothermal ones. Zircon LA-ICP-MS U-Pb dating shows that the age of the protolith of the garnet-bearing plagioclase gneiss is 254.5Ma±4.2Ma（MSWD=0.16）, and the age of its metamorphism is (242.7±2.3) Ma（MSWD=0.11）.In combination with regional geological information, the authors hold that the metamorphism of garnet-bearing plagioclase gneiss was related to the collision and orogeny of Paleo-Tethys, suggesting that the Western Kunlun orogenic belt was still in the period of Paleo-Tethys collision in early Middle Triassic.