Facies variations in response to tectonic evolution, climate and sea-level changes since the Late Cretaceous in Wuhu region, Eastern China

Abstract

Eastern China has a complex environmental dynamics system in the western Pacific tectonic domain, and the study of its sedimentary records controlled by tectonic movements is distinctly significant for exploring sea-land interactions, global climate change and sea level fluctuations. A reliable OSL (Optically Stimulated Luminescence) chronostratigraphic framework was established based on a systematic investigation of the stratigraphic lithology of the boreholes in Wuhu area, Eastern China, and the depositional environment since the Late Cretaceous was reconstructed by multiple environmental proxies. Significant regional changes in sedimentary activity since the Mesozoic indicate that the Yanshan movement and the Neotectonic movement controlled the evolution of sedimentary basins and fracture tectonics in the study area and influenced the paleo-geographic environment and sedimentary patterns in a regional geotectonic context. Since the Middle Pleistocene, the temperature and sea level trends were split into six stages, four of which (MIS 6, 4, 3 and 2) can be categorized as periods of decline, with MIS 1 being a period of significant increase. The other phase (MIS 5) was characterized by violent fluctuations in climate and sea level, with periods of increase in MIS 5a, 5c and 5e and decrease in MIS 5b and 5d. Sedimentary process in eastern China are mainly controlled by regional geotectonic activity, and the specific evolution of the depositional environment is also influenced by the combined effects of regional climate and sea level.