Evolution and Controlling Factors of Sedimentary Flux of East Asian Continental Margin since the Cenozoic

Wang Haiqin; Ding Weiwei; Wang Fei

doi:10.3799/dqkx.2025.099

Abstract：The East Asian continental margin located at the convergent and collisional boundary of the Pacific Plate and the Eurasian Plate,is not only the most tectonically and climatically active region in the world,but also an important place of the sedimentary"source to sink"process since the Cenozoic,However,the sedimentary dynamic processes and key controlling factors of basins at different latitudes remain unclear.This study calculates and statistically analyzes Cenozoic sedimentary flux in high-latitude(Okhotsk Sea),mid-latitude(Japan Sea,East China Sea),and low-latitude(South China Sea)basins.It is found that the evolution of sedimentary flux along the East Asian continental margin shows pronounced latitudinal differentiation:Mid-to Low-latitude basins(South China Sea,East China Sea,and Japan Sea)are primarily influenced by the coupling of tectonics,East Asian monsoon,and river systems.During the Late Miocene(11.6-5.3 Ma),the uplift of the Tibetan Plateau resulted in river reorganization and the intensification of the East Asian winter monsoon,reducing sedimentary flux by approximately 1/3 compared to the Middle Miocene.Since the Pliocene(5.3-0 Ma),the strengthening of the East Asian summer monsoon and the uplift of Taiwan Island increased it by 2 to 3 times compared to the Late Miocene,while the Japan Sea was mainly controlled by monsoon and local tectonics.High latitudes basin(Okhotsk Sea)is subject to the synergy of tectonics and glaciation.During the Middle to Late Miocene(16.0-5.3 Ma),global cooling events caused a decline in sedimentary flux by approximately 60％compared to the Early Miocene.Since the Pliocene(5.3-2.5 Ma),the expansion of the Heilongjiang River(Amur River)basin and the uplift of Sakhalin Island have led to an approximately 2-fold increase in sedimentary flux.