Abstract:Based on the restudy of core 07SR01 and the seismic profile in Xiyang tidal channel off north Jiangsu coasts using multidisciplinary methods, such as geomorphology, sedimentology, chronostratigraphy, seismic stratigraphy and sequence stratigraphy, and the further stratigraphic correlation between core 07SR01 and adjacent studied cores, this paper confirmed that the sea area experienced a series of environmental changes mainly controlled by sea level changes since about 35 ka BP(late MIS 3), sediment supply of paleorivers that flowed to the South Yellow Sea and minor structural subsidence, which are coastal barrier island, freshwater lacustrineswamp, riverfloodplain, coastal marsh, tidal sand ridges and tidal channel. Thus, the parasequence of the late period of the last interstadial, including highstand system tract and forced regressive wedge system tract, and the parasequence of the postglacial period, including transgressive system tract and highstand system tract, belonged to the fifthorder sequence stratigraphy have developed. The tidal sand ridges in sea area might begin to develop since the seawater covered the study area during the postglacial transgression about 9 cal ka BP, just were submerged sand ridges until the Yellow River switched its river mouth southward to north Jiangsu during 1128~1855 A.D.. Especially when the Yellow River totally captured the Huaihe River after 1494 A.D., a huge amount of sediments filled the tidal channel, some submerged sand ridges could develop to emerged ones. The development of Xiyang tidal channel was not due to the erosion of tidal sand ridges during the late Holocene, it has had an embryonic form since the highest sea level period in Holocene and lasted until 1128 A.D., and became a modern tidal channel, experiencing a process of silting during 1128~1855 A.D. and scouring during 1855 A.D.~now, influenced by the Yellow River. Xiyang tidal channel had a tendency of broadening and deepening to some extent in the future, influenced by strong tidal current scouring and human beings activities.