seismometers

Ocean bottom seismometer(OBS)can be used to detect seismic wave for the moving ship.But data quality from experiments has often been disappointing because of low signal-to-noise ratio(SNR).Many of these problems result from motion of the OBS package that is decoupled from motion of the ocean floor.In this paper the theory of coupling of OBSs to soft sediments has been summarized.And arrive at results suggesting that OBS packages should be designed with:① the minimum mass,② the rational radiu of area in contact with the sediment,③ density of the OBS approximately ambient medium,④ a low profile and a small vertical cross section with water,and ⑤ low density gradients,and maximum symmetry about the vertical axis.Besides structural analysis has been done for the commissioned OBS based on the theory.