Geological Characteristics and Zircon U-Pb SHRIMP Dating of the Plagiogranite in Amduo Ophiolites, Tibet
详细信息
- 责任者：Sun Lixin (Tinjin Institute of Geology and Mineral Resources ; Tianjin 300170 ; China) ; Bai Zhida
- 刊名：Geological Survey and Research
- 出版年：2011
- 卷期：34(1)
- 关键词：斜长花岗岩 ; plagiogranite ; 铀—铅计时 ; U-Pb dating ; 西藏 ; Tibet
- 页码：p.10-15
- 图表：3 illus., 4 tables, 18 refs.
- 分类号：0801
- issnNo：ISSN1672-4135
- isbnNo：CN12-1353/P
摘要
The Amduo plagiogranite is distributed in the Duopuer River area, Amduo County, Tibet. Based on the regional geological survey of the 1 : 250 000 Amduo County sheet, the authors studied the geological characteristics of the plagiogranite and discussed its origin and age according to the prtrological, geochemical and isotope age evidence. The result shows the plagiogranite is ocean plagiogranite with higher contents of Na, Sr, lower contents of K, Rb and ∑REE, which means its mantle origin. Its zircon SHRIMP age (206Pb/238U age) is (188.0±2) Ma, belongs to Early Jurassic, which is the same with the west part of the Bangonghu-Nujiang junction. In addition, this study also provides petrological and isotope age evidence for the ophiolite of the middle Bangonghu-Nujiang Suture.