1. SHRIMP dating of zircons from the Caledonian Xiongdian eclogite, western Dabie Mountains, China
- Author
-
Ian S. Williams, Weiran Yang, Dunyi Liu, and Ping Jian
- Subjects
Paleontology ,Peripheral zone ,Multidisciplinary ,Radiogenic nuclide ,Metamorphic rock ,Geochemistry ,Metamorphism ,Eclogite ,Geology ,Zircon ,Shrimp - Abstract
This note reports the SHRIMP U-Pb data of zircons from the Caledonian Xiongdian eclogite, western Dabie Mountains. Zircons from the rock occur mainly in garnet and other metamorphic minerals with sharp boundaries and exhibit textures growing under metamorphic conditions. Analyses of 7 grains give206Pb/238U ages ranging from 335 to 424 Ma, showing a certain degree of radiogenic lead loss. This suggests a minimum age of (424± 5) Ma for the metamorphic zircons, as well as the high-pressure metamorphic event. The outer peripheral zone of a zircon gives206Pb/238U age of about 300 Ma. Combined with Sm-Nd,40Ar-39Ar, U-Pb and207Pb/206Pb ages, the peak metamorphism of the Xiongdian eclogite is documented between 424–480 Ma.
- Published
- 2001