SUBMARINE TOPOGRAPHY AND SEDIMENTARY CHARACTERISTICS OF OFFSHORE WIND FARM IN HEISHAN ISLAND OF SHANDONG

The sea area off the Shandong Peninsula is rich in wind resources and there are excellent conditions for large-scale development of wind energy. In order to understand the topography and sediment distribution patterns of the seabed, so as to promote the development of offshore wind farms smoothly, the sea area near the Heishan island was selected as a case for geological study. An integrated geological and geophysical survey was then undertaking in the selected area. The survey data suggests that the seafloor topography of the study area is rather gentle and the water depth changes from 10 m to 25 m, 17.5 m on average. The sediment in the study area is cyan gray, gray and light brown in color and dominated by silty sand which covers over 75% of the whole area. The kurtosis of the sediment varies from flat to medium to sharp. In the west part of the study area, the sorting of the seafloor sediment changes from 1.35 up to 1.80. while in the east part the sorting of the sea bottom sediment varies from 0.90 to 1.75. The mean grain size of bottom sediments of the whole study area ranges from 4.3Φ to 5.9 Φ and is silt dominated. The topography and sediment characteristics reflect that the study area is an area with weak hydrodynamic effect and therefore suitable for offshore wind power development and other kinds of sub-bottom constructions.