An end-Permian two-stage extinction pattern in the deep-water Dongpan Section, and its relationship to the migration and vertical expansion of the oxygen minimum zone in the South China Basin

Abstract

The diversity and last appearance patterns of different taxa, inhabiting varied palaeo-water depths, can provide significant insights into the deterioration process of palaeoecosystems. This paper systematically summarizes the last appearance of the end-Permian planktons (including deep-water, intermediate-water, and shallow-water radiolarians) and benthos (including ostracods, foraminifers, brachiopods and bivalves) from Dongpan, a deep-water section of South China. Results show that the deep-water radiolarian Albaillellaria was the first order to go extinct, quickly followed by the intermediate- and shallow-water radiolarians and bottom-water ostracods and foraminifers. This was followed by the extinction of the bottom-water brachiopods and bivalves. We propose that the two-stage extinction pattern was related to the end-Permian migration and vertical expansion (both upward and downward) of an oxygen minimum zone (OMZ) along the southern margin of South China.