THICKNESS VARIATION AND PROVENANCE OF MID-HOLOCENE MUD SEDIMENTS IN THE CENTRAL AND WESTERN SOUTH YELLOW SEA

The thickness and forming age of the Holocene mud deposits are studied with the thirty-five cores collected from the Central Yellow Sea. Our results suggest that the pattern of Yellow Sea Warm Current was formed simultaneously when the sea-level reached its maximum at 7.0 cal.kaBP. and has remained stable with little fluctuation since then. Fine sediments were transported by the coastal current to the nearshore and offshore areas, and lead to the deposition of mud deposits in two depositional centers:the offshore area of Southern Shandong Peninsula (thickness 7.7 meters) and the Central South Yellow Sea (thickness 9.0 meter maximum). The fine sediments are mainly supplied by the modern and old Yellow River, and at the same time, the Changjiang River, Korean Peninsula, small rivers and coastal sediments around the Shandong Peninsula as well as the suspensions from the outer-seabed erosion also have certain contribution to the mud supply. The maximum depositional rate of the two centers is 1.283 and 1.286 mm/a respectively. Obvious difference of sedimentation rate in scale of hundred years is observed. It is probably related to the compaction of mud deposits and unstable sediment supply owing to the diversions of the old Yellow River in the history. The two depositional centers has retained in stable. High resolution research of palaeoenvironment changes in the mud area is required on the basis of this study.