• 责任者：He Shiping (Xi’an Center of Geological Survey ; Xi’an Institute of Geology and Mineral Resources ; China Geological Survey ; Xi’an 710054 ; China) ; Li Rongshe
• 刊名：Earth Science Frontiers
• 出版年：2013
• 卷期：20(5
• 关键词：地质年代学 ; geochronology ; 铀—铅计时 ; U-Pb dating ; 片麻岩 ; gneisses ; 青藏高原 ; Qinghai-Tibetan Plateau
• 页码：p.15-24
• 图表：5 illus., 2 tables, 30 refs.
• 分类号：0802
• issnNo：ISSN1005-2321
• isbnNo：CN11-3370/P

     It is closely concerned that whether pre-Cambrian basement exist in Qiangtang area, Qinghai-Tibet Plateau. The formation age of Ningduo Rock Group that belongs to one of the metamorphic rocks of the Changdu Block shows great significance in resolving this question. The age 1044-30 Ma of the youngest erosion provenance is obtained by LA-ICP-MS zircon dating in biotite plagioclase gneiss （para metamorphic rock） from the Ningduo Rock Group in Xiaosumang area, Yushu County, Qinghai Province. This age repre- sents the lower limit formation age of the Ningduo Rock Group. Meanwhile, the crystallization age 990. 5 - 3.7 Ma of the gneissie biotite granite that intruded into the Ningduo Rock may represents the upper limit formation age of the Ningduo Rock Group. The formation age of the Ningduo Rock Group can be constrained between 1044 - 30 and 990.5 -3.7 Ma （Late Mesoproterozoic to Early Neoproterozoic）. In addition, there is a second peak age of 530 Ma of the biotite plagioclase gneiss of the Ningduo Rock Group, which may represent the age information of Pan-African Movement in Qiangtang area.