Influence of watersaturated sedimentary layer on recording of seismic signals by bottom seismograph

Specific distortions exist, which are caused by resonance during recording of seismic signals at the sea bottom. In a number of papers these distortions are explained by the fluctuations of heavy seismograph case on a soft elastic layer of sediment. There are however experimental results, which do not correspond to such models. In this paper the reological characteristics of seabed sediment are considered, which practically were not taken into account earlier. A viscous - plastic model (Bingham model) was used for research. Parameters of the model were defined on the basis of the experiment. The obtained estimates showed that in the frequency range 0.003-30 Hz used in broadband seismology the influence of mass seismograph on the results of recording on soft bottom is negligible. Essential distortions can appear only when the seismograph is located on rubber-like foundation: peat, aggregations of seaweed, etc. The resonant phenomena during recording of signals on seabed can appear from propagating seismic waves through the water-bearing sediment layer. These phenomena manifest themselves more clearly for shear waves, compression waves propagating through sediment layer with comparatively smaller distortions.