U-Pb zircon age from the base of the Ediacaran Doushantuo Formation in the Yangtze Gorges,South China： constraint on the age of Marinoan glaciation  

作　　者：ChongyuYin FengTang YongqingLiu LinzhiGao PengjuLiu YushengXing ZhiqingYang YushengWan ZiqiangWang 

机构地区：[1]InstituteofGeology,ChineseAcademyofGeologicalSciences,Beijing100037,China [2]BeijingSHRIMPCenter,Beijing100037,China [3]ChinaUniversityofGeosciences,Beijing100083,China

出　　处：《Episodes》2005年第1期48-49,共2页地质幕（英文版）

摘　　要：The reported new U-Pb age by sensitive high-resolution ion microprobe (SHRIMP Ⅱ) on zircon was obtained from a tuff sample at the basal Doushantuo Formation in the Jiuqunao section, which situated at the western limb of the Huangling anticline in the Yangtze Gorges in Zigui, Hubei, South China. Eighteen spots of zircons were analyzed and they form two clusters: one includes three spots, with an inherited age of 784+ 15 Ma (MSWD=0.05); the other consists of 15 spots and gives a weighted mean ^206pb/^238U age of 628.3±5.8 Ma (MSWD=0.86). It is the first SHRIMP U-Pb zircon age obtained nearly the base of the Doushantuo Formation of Ediacaran and represents a maximum age of the Doushantuo Formation It also forms an age constraint on the upper limit age of the Nantuo (Marinoantype) glaciation.

关 键 词：中国南部 扬子江峡谷 同位素年代测定 冰川作用 

分 类 号：P512.41[天文地球—地质学] P597.3