Carbon and Oxygen Isotopic Compositions of the Dengying Formation Maidiping Member of Upper Sinian and Sinian-Cambrian Boundary Division in Ningnan Area, Western Panzhihua, Sichuan Province, China

• 责任者：Yu Guangmo (Faculty of Resource and Environment ; Southwest University of Science and Technology ; Mianyang 621000 ; China) ; Liang Bin
• 刊名：Geological Bulletin of China
• 出版年：2010
• 卷期：29(6)
• 关键词：震旦纪 ; Sinian ; 寒武纪 ; Cambrian ; 四川 ; Sichuan Province
• 页码：p.901-906
• 图表：4 illus., 1 table, 22 refs.
• 分类号：1200
• issnNo：ISSN1671-2552
• isbnNo：CN11-4648/P

This paper has discussed composition characteristics of carbon and oxygen isotopes, and discussed Sinian-Cambrian boundary of the area according to the δ¹³C content variation in the profile. The results showed that the δ¹³C values of the Maidiping bed dolostone are between -3.19‰～2.86‰ with an average value of 0.10‰; the δ¹⁸O values are between -10.75‰～-5.17‰ with an average value of -7.82‰. Within the profile, the δ¹³C values follow a certain law. The δ¹³C variation tendency of the Maidiping Member dolostone is similar to those of the strata during the same period worldwide. Therefore it can be used as geochemistry symbol for defining the Sinian-Cambrian boundary.