Identification of Types and Thickness Layers of Seabed Sediments

Abstract The sea toll program is one of the developments in the water sector that has a major influence on the areas it passes through. The sea highway acts as sea transportation that is carried out regularly and connects various ports in the territory of Indonesia. With the sea highway, there will be increased activity in the port area which will certainly increase the risk of shipping safety. This encourages periodic mapping and identification to reduce shipping risks that can occur. One of the activities to conduct mapping and identification is by hydrographic survey. There are many acoustic instruments that can be used for mapping the bottom of the water, in this study a sub-bottom profiler and side scan sonar were used. From the results of the study, the depth in the Berlian Terminal dock pool area ranges from 3.1 to 13 meters. The average thickness of the sediment layer from each survey lane is 1.01 m, 0.93 m, 1.41 m, 1.20 m, 1.37 m, 1.86 m, 1.15 m. The results of side scan sonar processing of the seafloor image interpretation produced several features consisting of pitted seafloor, ship grounding, and dredged areas. The distribution of sediment types was successfully classified into three classes consisting of silty clay, silty loam, and silty sand. This result is supported by sediment sampling which shows that the majority of sediment types in the study area was silty.