Organic Matter Accumulation Mechanisms of Shale Series in He-third Member of Eocene Hetaoyuan Formation, Biyang Depression, Eastern China

Abstract

The relationship between the organic matter (OM) accumulation and the climate, salinity, redox condition, and productivity changes has been investigated based on the analysis of major, minor and trace elements, and the biomarker parameters of shales from organic-matter-rich interval (ORI) 5 and 3 in the He-third member of the Eocene Hetaoyuan Formation, Biyang Depression. Results indicate that the stratified water column with high-salinity anoxic conditions and shallow water enhanced the OM storage within ORI 5, while high productivity coupled with oxygen-depleted bottom water in the relatively deep basin favored the OM accumulation within ORI 3.

Keywords:

• sequence stratigraphic framework
• OM accumulation
• saline environment
• organic-rich intervals
• Biyang depression
• He-third member of Hetaoyuan Formation