Geochemical Characteristics and Zircon U-Pb Age of the Plagiogranite in Gaize Ophiolite of Central Tibet and Their Tectonic Significance

• 责任者：Fan Shuaiquan (Key Laboratory of Continental Collision and Plateau Uplift ; Institute of Tibetan Plateau Research ; Chinese Academy of Sciences ; Beijing 100085 ; China) ; Shi Rendeng
• 刊名：Acta Petrologica et Mineralogica
• 出版年：2010
• 卷期：29(5)
• 关键词：斜长花岗岩 ; plagiogranite ; 铀-铅计时 ; U-Pb dating ; 西藏 ; Tibet
• 页码：p.467-478
• 图表：10 illus., 2 tables, 53 refs.
• 分类号：0801
• issnNo：ISSN1000-6524
• isbnNo：CN11-1966/P

Located in central Tibet, the Gaize ophiolite is a key element within the middle part of the Bangong Co-Nujiang suture zone, marking the boundary between the Lhasa and Qiangtang blocks. Based on detailed studies of field geological background and petrographical features, the authors selected some samples to analyze the whole-rock content of major elements, trace elements and rare earth elements and determine the ages of zircons separated from the plagiogranite by La-ICP-MS U-Pb method. The results show that the plagiogranite crops out as dykes intruding into gabbro, basalt and basaltic andesite with no thermal aureole along the boundary between the plagiogranite and associated lavas comprising basalt and basaltic andesite.