ORIGIN OF OBS-RECORDED SEISMIC NOISE

Abstract

Describes the factors that control the amplitude and frequency of sea-floor seismic noise in the frequency band f=3...20 Hz and discusses some sources of the most significant disturbances. The low frequency disturbances (f<10 Hz) are supposed to be caused by bottom currents of tidal and tectonic origin acting directly on the recording ocean-bottom seismograph. In neovolcanic areas, the complex frequency-time pattern of the disturbances is related to volcanic activity. The similarity of the T phase and noise recordings suggests that the bottom seismic noise can be produced by sound waves of different origins.