Inshore Geological Hazard Of Pearl River Estuary In The North Of South China Sea

South China Sea has the most complex oceanic geologic hazard condition and most potential danger. The north of South China Sea especially the area of Pearl River estuary is an important place where is the window of the economy exploitation. In this paper miltibeam system of GeoSwath Plus is used in the water depth measure of outer sea area of Pearl River estuary. High density of water depth data and sidescan data are got through the nice miltibeam data processing. Through the analysis of the data and charts, a hazard geomorphology-weighted statistical model was used to give a quantificational estimate of the geologic hazard. Now there are different kinds of miltibeam system in home. According to the different frequency miltibeam system can be divided into three kinds, shallow water ,middle water and deep water miltibeam system. According to the theory of beam forming(beamforming and inteferometry), miltibeam system can be divided into two kinds, conditional miltibeam and inteferometry miltibeam, which have some differences in the performances because of their different theory of beam forming. A particular compare about the difference between conditional miltibeam system and GeoSwath Plus is done on their theories and performance in the paper.Based on the research of regional geology and quaternary geology in the survey area and through the discuss of the general situation of the landform (such as the hydrodynamic condition and the structure character) , some influencing factors of the submarine terrain in the sea area are achieved with the study of bathymetric chart and some terrain profiles.The influencing factors and the potential danger causing by the geology hazard in this sea area are achieved by the study of the geomorphic type found there. The analysis and statistic of the type of the marine geology hazard, by the adequate study about the geologic hazard environment in the survey area and the geologic hazard factors with geologic hazard factor as evaluating gene, the stability of submarine is evaluated in different area by using the hazard geomorphology-weighted statistical model. With the evaluating result the level of submarine stability is ensured based on the submarine geomorphology type.