Inconsistency of the biotic and environmental events in North China during the great Permian-Triassic transition

Abstract

Studies from the terrestrial facies indicate that the life and environment experienced a similar and interrelated process on land and in water through the great Permian-Triassic transition, that is, the quick temperature rising in the latest Permian associated with the great end-Permian mass extinction, a subsequent prolonged superhigh temperature throughout the Early Triassic with extensive red sediments and extremely barren fossils, and the climate returning to normal during the Middle Triassic with the reconstruction of the Mesozoic ecosystems. However, the refined integrative study on the Permian-Triassic stratigraphy and fossil and depositional records from North China displays some inconsistency of the biotic and environmental events through the great Paleozoic-Mesozoic transition. For instance, the red beds and related arid climatic indicators such as paleosols show the temperature rising through the mid-late Permian. The Permo-Triassic mass extinction on land looks clearly prior to the major marine crisis whereas the major changeover of the depositional systems, i.e. the river system transforming from meandering to braided rivers, obviously lagging behind. The recovery of animals recorded from trace fossils happened in the late Early Triassic while the plants showed a gradual reconstruction of the Mesophytic communities during the Middle-Late Triassic.