The impaction of typhoon on seafloor ambient noise by analyzing the OBS recording data
利用海底地震仪数据分析台风对海底环境噪音的影响

Ocean Bottom Seismometer (OBS) deployed in the seafloor can record information of ocean ambient noise, and typhoon can generate elastic waves propagating through the seafloor directly or indirectly. These factors cause great changes on OBS recording data to some extent. The OBS data during the process of typhoon was analyzed, and the methods of optimum filter were used in order to separate signals. After those work, we found that wind wave and ground swell were well recorded by short-period OBSs for the first time, and a new mode which typhoon affected seafloor ambient noise was put forward. We get three preliminary conclusions from above analysis: 1) Wind wave and ground swell caused by typhoon have their own distinctive modes to affect seafloor ambient noise;2) The range and extent of seafloor ambient noise are obviously different which have been strengthened by two above waves;3) Short-period OBSs can clearly record the information of ground swell, whose dominating period is 6--8 seconds and its energy is generally steady (we call it "8-second phenomenon") ; These results will have great significance for the future research on marine seismology and other aspects of oceanography.