• 责任者：Gao Linzhi (Institute of Geology ; CAGS ; Beijing 100037 ; China) ; Ding Xiaozhong
• 刊名：Geological Bulletin of China
• 出版年：2011
• 卷期：30(10)
• 关键词：前寒武 ; Precambrian ; 凝灰岩 ; tuff ; 铀—铅计时 ; U-Pb dating ; 湖南 ; Hunan Province
• 页码：p.1479-1484
• 图表：5 illus., 1 table, 23 refs.
• 分类号：1300
• 出版序号：20122602
• issnNo：ISSN1671-2552
• isbnNo：CN11-4648/P

This paper reports a SHRIMP U-Pb age (855 ± 5) Ma of metamorphic tuff from the Fengzichong Formation. Although zircons have different forms, their CL images show typical magmatic oscillatory zoning. The zircons have relatively high content of U and Th, with Th/U ratios vary in the range of 0.32~0.87. Therefore, they are of magmatic origin. The new data change the traditional stratigraphic correlation of the Cangxi Complex-Group in northeastern Hunan Province.