Digitalized Earth's most severe sea-level regression and extinction

Abstract

End-Permian mass extinction is the largest bio-crises in the past 542 million years in Earth's history. Despite half a century of study, what caused the catastrophe remains equivocal. Fossil collections in the study area of Bayan Har, NW China, suggest a continuous Permian sequence, whereas most mid-to-upper Permian strata were missing. By correlating the Permian sequence reconstructed from reworked carbonate clasts with the measured Permian section, we corroborate a sea-level fall of at least 354 m caused by plume-induced uplift, resulted in the erosion of the last 15-Myr Permian carbonate strata, from Uppermost Permian to the fusulinid zone. The marine regression and resultant erosion occurred not only in China but also in Canadian Arctica[1], Oman[2], Canadian Rockies[3], Norway[3], North America[3] all over the world. New sections and digitalized sea-level regression demonstrate that the period of extinction falls within the hiatus, a break in deposition between the uppermost Permian carbonate strata and the clasts reworked from Permian platforms, representing a duration of sea-level drop 354 m. Carbonate clasts, Siberian Traps volcanism, global warming, anoxia, and ocean acidification are all post-extinction geological events. Why did the extinction occur during the falling stage? We will never know because we can't study a hiatus unrepresented by strata unless we associate the extinction with the sea-level drop.