Geochemistry, Zircon SHRIMP U-Pb Dating and Origin of Alkali-Rich Porphyries in Beiya Area, North Erhai Lake , Western Yunnan Province , China
详细信息
- 责任者：Xiao Xiaoniu (State Key Laboratory of Geological Processes and Mineral Resources ; Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education ; China University of Geosciences ; Beijing 100083 ; China) ; Yu Xuehui
- 刊名：Geological Bulletin of China
- 出版年：2009
- 卷期：28(12)
- 关键词：斑岩 ; porphyry ; 铀—铅计时 ; U-Pb dating ; SHRIMP定年 ; SHRIMP dating ; 云南 ; Yunnan Province
- 页码：p.1786-1803
- 图表：4 illus., 2 tables, 23 refs.
- 分类号：1300
- issnNo：ISSN1671-2552
- isbnNo：CN11-4648/P
摘要
In this paper, SHRIMP U-Pb ages, TY-1(31.5±1.1 Ma), TY-3(31.34±0.73 Ma) of Tanyao quartz syenite porphyries in Beiya are published for the first time, which suggest that the intrusions are formed in Cenozoic. The results show that alkali-rich porphyries in Beiya are characterized by enrichment in alkaline and potassium. Based on the characteristics of major elements, trace elements, REE, and isotope geochemistry of alkali-rich intrusion in Beiya area, the authors concluded that they have many similar petrological and geochemical characteristics to adakites, but are quite different from those of typical features of adakite defined by Defant and Drummond (1990), which are more close to those adakites in Hoh Xil Area.