沉积与特提斯地质2018，Vol.38Issue(2)：103-112,10.
滇西澜沧岩群碎屑锆石U-Pb定年及其地质意义
U-Pb dating of the detrital zircons from the Lancang Group Complex in western Yunnan and its geological significance
摘要
Abstract
Although numerous previous studies,no direct evidences of geological ages are recorded for the Lancang Group Complex in western Yunnan. The U-Pb age data of the detrital zircons in sericite quartz schist from the Lancang Group Complex in the Changputang-Datianshan zone have provided convincing evidence for the formation age of the Lancang Group Complex. The cathodoluminescence (CL ) images show that these zircon crystals generally display the well-defined oscillatory zonation and suggest a magmatic origin of the zircons. The age data for the detrital zircons in the sericite quartz schist sample PM08-B1 range between 452 and 3016 Ma,with the youngest age group of 452 ± 26 Ma,implying that the maximum depositional age of the Lancang Group Complex is less than 452 ± 26 Ma. One zircon grain with a U-Pb age of 255 ± 3Ma exhibits a slight cathodoluminescence image and has no internal structures,which is characteristic of a type of metamorphic recrystallization zircons and in general aggrement with the previous data. In general,the Lancang Group Complex is dated at a depositional age of less than 452 ± 26 Ma,The U-Pb age (255 ± 3 Ma)of the metamorphic crystalline zircons reveals that the metamorphic events once took place during the Late Permian.关键词
澜沧岩群/碎屑锆石U-Pb定年/滇西Key words
Lancang Group Complex/U-Pb dating of detrital zircons/western Yunnan分类
天文与地球科学引用本文复制引用
徐云飞,丛峰,刘军平,孙柏东,黄晓明..滇西澜沧岩群碎屑锆石U-Pb定年及其地质意义[J].沉积与特提斯地质,2018,38(2):103-112,10.基金项目
中国地质调查局地质调查项目(编号121201010000150007和12120114060201)资助 （编号121201010000150007和12120114060201）
