TITLE:
A Discussion on Sedimentary Environment of the Guanyinqiao Member from the Upper Ordovician in Yangtze Area
AUTHORS:
Yunpeng Xiao, Wenjun Liang, Chunyan Sun, Mingyi Hu
KEYWORDS:
The Guanyinqiao Member, Sedimentary Environment, Deep-Sea, Mass Extinction, Yangtze Area
JOURNAL NAME:
Open Journal of Yangtze Oil and Gas,
Vol.3 No.3,
July
17,
2018
ABSTRACT: Based on the comparison between the sedimentary rate of the Guanyinqiao Member and modern deep sea, as well as the analysis of paleoecology, biopalaeogeographic features, sea level changes and comprehensive sedimentary characteristics, it is demonstrated by the authors that the Guanyinqiao Member in the Yangtze area is formed in the deep sea environment and belongs to contourite facies. The relationship between the events and the mass extinction at the turn of Ordovician-Silurian is discussed. The authors believe that the high-frequency volcanic events, which are widely developed at that time, may be the main and direct cause of the extinction. The coupling effects of volcanic events, iridium and carbon isotope abnormities and the initial hypoxia events in the early Silurian may be the main cause of the extinction of the Hirnantia-Dalmanitina fauna.