DISTRIBUTION PATTERN AND DEPOSITIONAL MECHANISM OF SURFACE SEDIMENTS OFFSHORE SOUTHERN SHANDONG PENINSULA

Grain-size analysis and sediment classification for 137 surface sediment samples taken from the offshore area of the Southern Shandong Peninsula have been carried out to reveal the distribution pattern of surface sediments and its relation with source and sedimentary environment.The results indicate that silt component dominates the surface sediment and decreases gradually seaward with the isopleths of content parallel to the coastline in northeast-southwest direction.Silt and sandy silt are the deposits distributed most widely in this area and cover almost 60% of the total research area.There are two different distribution patterns around the cape of Laoshantou.In the east to the Laoshantou,the surface sediments are simple and widely distributed.The sediment mainly comes from the Yellow River carried by the Yellow Sea Coastal Current,Yellow Sea Warm Current and near shore current system.In the west of the Laoshantou, however,the surface sediments are rather complex and diversified and distributed as patches.The sediment in this area is originated from the Shandong Peninsula and reworked by the tidal current and wave.