Numerical Simulation of Rayleigh Waves Interaction with Compact Deepened Velocity Heterogeneities

Basing on numerical simulation we suggested criteria of classification for big and small inclusions in comparison to surface Rayleigh wave length. The inclusions with size of 1.5-2 and more of wavelengths could be regarded as large ones since positions of their boundaries could be found precisely in the intensity pattern if the inclusions are exposed with Rayleigh waves from all sides. At such an exposure depth and lateral position of “focal points” of small heterogeneities (when size of heterogeneity is less than Fresnel zone) could also be defined precisely independently from the relation between the size and wave length, however the shape of the heterogeneity takes a form of a generalized cloud with size of about Fresnel zone. Two small heterogeneities begin to break up in the intensity pattern if distance between them constitutes 20% of sounding wave length or more.