Sedimentary characteristics of Holocene sediments in the Middle-Western South Yellow Sea

The South Yellow Sea is a typical wide continental shelf sea with abundant terrestrial sediment supply. A variety of sedimentary records have been formed since the Holocene period, and they have characteristics in terms of high resolution, discontinuous spatial distribution, and depositional hiatus. Based on abundant high-resolution shallow seismic profiles acquired in the South Yellow Sea in recent years and combined with lithologic characteristics and AMS¹⁴C dating data of several cores, the spatial and temporal distribution of Holocene sediments in the South Yellow Sea were revealed systematically and meticulously. According to their spatial distribution, genetic mechanism and provenance, the Holocene sediments in the South Yellow Sea were divided into four independent sedimentary bodies, which show different acoustic reflection characteristics, including mainly accretion and aggradation reflection, parallel or transparent weak reflection, medium or high angle accretion reflection, and medium-high angle tilt-oblique reflection. By estimation, the river sediment input accounted for 78% of the Holocene sediments in the South Yellow Sea, and the other sources were mainly the bottom bed materials from strong marine dynamic erosion, transformation, and redistribution during transgression. The study is expected to provide more-reliable evidence for the research of dynamic mechanism of sedimentary evolution process of Holocene deposits in the South Yellow Sea.