Abstract: The Lanshayang tidal channel is one of the major tidal channels in the radial sand ridges area of the South Yellow Sea. The evolution of sedimentary environment of the channel since the late Pleistocene is studied based on regional literature review and core data analysis. The analysis of core 07SR09 in the channel includes sedimentary facies, grain size, 14C dating, foraminifera identification, and magnetic susceptibility.
The paleo Yangtze River flows into the South Yellow Sea since the late Pleistocene. The results of grain size analysis show that the content of fine sand was decreasing because of the southward movement of the paleo Yangtze River. We argue that this area was influenced by deposition after the southward movement of the paleo Yangtze River, most likely from the paleo Huanghe River, or the finer particles brought by tidal action. And these later deposited fine particles diluted the original sediment grain size composition of this area. According to the analysis of magnetic susceptibility, and the distribution of foraminifera species and quantitative characteristics, the hydrodynamic conditions of the Lanshayang tidal channel have become steady gradually since the late Pleistocene, and the tidal channel is excellent for a natural deepwater channel