The influence of the dispersion on the surface Rayleigh wave propagation

The surface Rayleigh waves propagated along the boundary of the half-space covered by thin layer with different density are analyzed. A frequency dispersion of phase wave velocity appears in this model due to the presence of the heterogeneity and it is similar to the interferential surface seismic wave dispersion. The plot of frequency dispersion curve of the phase surface wave velocity is presented. Calculation formula for the surface wave response on the pulse action to the half-space with surface heterogeneity by a density medium model is derived. Response oscillogramms corresponding to the receiving points with their consequently removing along the surface are demonstrated. Obtained results show the character of the increase of the duration of the wave pulse responses by the growth of the distance from the source. The time delay of the wave arrival and the decrease of the surface wave level with enlarge of source-receiver distance are discussed.