摘要
采用SHRIMP和LA-ICP-MS测年方法,对湖南锡田花岗岩体8个样品中的锆石进行了U-Pb同位素年代学测定。对样品中的锆石进行成因研究,在阴极发光图像上锆石具有典型的振荡环带,呈现较高的Th/U比值特征,显示锆石为岩浆锆石。根据新获得的花岗岩SHRIMP和LA-ICP-MS锆石U-Pb数据,结合已经报道的高精度成岩年代学资料,将锡田岩体的岩浆活动归纳为2期4个阶段:印支期第一阶段,侵位于230～224Ma间,峰值在228Ma左右;印支期第二阶段,侵位于215Ma左右;燕山期第一阶段,侵位于160～147Ma间,峰值在151Ma左右;燕山期第二阶段侵位于141Ma之后。
In this paper,the U-Pb geochronology of zircon of the 8 samples in Xitian pluton of Hunan Province has been measured,using SHRIMP and LA-ICP-MS technique. All zircons from Xitian granite pluton have the oscillatory zoning and high Th / U ratio revealed by the cathodoluminescence （ CL） images,which suggest that zircons are magmatic zircons. Based on the new data and the latest reported high-precise dating of the related granites,the magmatic activities in the study area can be ascribed to four stages as follows： The first stage of Indosinian（230 - 224 Ma）,the peak was about 228 Ma; The second stage of Indosinian was about 215 Ma; The first stage of Yanshanian（160 - 147 Ma）,the peak was about 151 Ma; The second stage of Yanshanian was after 141 Ma.
出处
《现代地质》
CAS
CSCD
北大核心
2013年第4期819-830,共12页
Geoscience
基金
中国地质调查局区域地质调查项目([2011]02-14-04)
