C-isotope composition and correlation of the Upper Neoproterozoic in Keping area, Xinjiang

作     者：HE XiuBin, XU Bei & YUAN ZhiYun The Key Laboratory of Orogenic Belts and Crustal Evolution, Peking University Ministry of Education of China School of Earth and Space Sciences, Peking University, Beijing 100871, China 

作者机构：The Key Laboratory of Orogenic Belts and Crustal Evolution PekingUniversity Beijing 100871 China 

出 版 物：《Chinese Science Bulletin》 (中国科学通报)

年 卷 期：2007年第52卷第4期

页      面：504-511页

核心收录：

学科分类：070902[理学-地球化学] 0709[理学-地质学] 07[理学] 

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 40572133 and 40032010) 

主　　题：新疆 柯坪地区 晚震旦世 C同位素成分 冰川作用 

摘      要：C-isotope analysis of the carbonates in the Upper Neoproterozoic in Keping, Xinjiang indicates that the Qigebrak Formation and the Upper Sugaitbrak Formation mainly record positive C-isotope values, and a distinct positive excursion occurs in the lower part of the Qigebrak Formation. There are three negative excursions in the boundary between the Qigebrak Formation and the Cambrian, the uppermost and lowermost Upper Sugaitbrak Formation. These characters resemble those of the Upper Neoproterozoic in the Three-Gorge area, which suggests that the Upper Sugaitbrak Formation and Qigebrak Formation can be correlated with the middle and upper parts of the Doushantuo Formation and Dengying Formation, respectively. The negative excursion at the top of the Upper Sugaitbrak Formation corresponds to that at the top of the Doushantuo Formation, while the negative excursion at the bottom of the Sugaitbrak Formation can be correlated with that at the middle part of the Doushantuo Formation in the Three-Gorge area and that at the top of the Hangelchaok diamictites in the Quruqtagh area.