Mesozoic basin evolution of the East China Sea Shelf and tectonic system transition in Southeast China

Abstract

AbstractThe East China Sea Shelf Basin (ECSSB) is located on the south‐eastern edge of the Eurasian Plate. The tectono‐evolution and dynamic mechanism of the ECSSB are related to the collision of the Pacific Plate with the Eurasian Plate, and the remote pushing effect of the Indo‐Australian Plate remains a hot topic of debate. Based on the latest survey data, this paper mainly focuses on the evolution of the Mesozoic basin in the East China Sea Shelf by means of assessing the regional tectonic background, conducting structural physical simulation experiments, and applying balanced geological section recovery technology to discuss the processes of dynamic transition in Southeast China. Our data suggest that the ECSSB experienced an evolutionary sequence involving the pre‐Late Triassic passive continental margin; the Late Triassic–Middle Jurassic active continental margin extrusion‐depression; the extrusional stress from the low‐angle subduction of the Izanaki Plate under the Eurasian Plate; the late Early Cretaceous to Late Cretaceous active continental marginal extension faulted basin, during which the extensional stress originated from the lithospheric thinning and palaeoenvironment resulting from the subduction of the Palaeo‐Pacific Plate under the Eurasian Plate; and the Palaeogene back‐arc extension faulted sags. The transition time from the E‐W‐trending Palaeo‐Tethys tectonic system to the NE‐trending Palaeo‐Pacific tectonic system in Southeast China occurred at the end of the Middle Triassic. The low‐angle subduction and withdrawal of subduction of the Palaeo‐Pacific Plate probably represented the deep geological processes of the Mesozoic in Southeast China.