The placement of the Ediacaran-Cambrian boundary in deep-water realm in South China and the high-precision temporal framework for the Ediacaran-Cambrian transition in this region have not yet been completely solved. Recently, we have found two K-bentonite beds in the top of the Liuchapo Formation at the Pingyin section, Guizhou Province. It provides an opportunity for constructing the temporal framework of the transitional strata on the Yangtze Platform in South China and for determining the Ediacaran-Cambrian boundary in this area. In this study, we conducted high-precision CA-ID-TIMS U-Pb dating on zircons from the two K-bentonites. The ages of the two K-bentonites were precisely constrained at 536.40 +/- 0.47/1.1/1.2 Ma (2 sigma, n=7, MSWD=0.92) and 541.48 +/- 0.46/1.1/1.2 Ma (2 sigma, n=8, MSWD=1.3). Combining the geochronological results with organic carbon isotope data of chert in the topmost Liuchapo Formation from the section, we suggest that the EdiacaranCambrian boundary should be consistent with a significant negative organic carbon isotope excursion between the two K-bentonites. The scheme of the Ediacaran-Cambrian boundary in this study is of great significance for global correlation, and further for unravelling the information of the terminal Ediacaran-early Cambrian ocean.
Publication name |
SCIENCE CHINA-EARTH SCIENCES DOI: 10.1007/s11430-019-9590-0 |
Author(s) |
Wang, Wei; Zhou, Mingzhong; Chu, Zhuyin; Xu, Junjie; Li, Chaofeng; Luo, Taiyi; Guo, Jinghui |
Corresponding author(s) |
CHU Zhuyin zhychu@mail.igcas.ac.cn -Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China. -Chinese Acad Sci, Innovat Acad Earth Sci, Beijing 100029, Peoples R China. ZHOU Mingzhong mingzhongzhou@126.com -Guizhou Normal Univ, Sch Geog & Environm Sci, Guiyang 550001, Peoples R China. |
Author(s) from IGCAS |
LUO Taiyi | View here for the details
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