Abstract：In order to study the mechanism and propagation of Rayleigh surface wave in biphasic media and promote the development of data-processing method of Rayleigh surface wave, the authors applied finite difference method with staggered grids to simulate the 2D isotropic elastic media based on the elastic wave equation, and made a comparison between the analytical and numerical solutions. On such a basis, the PML absorbing boundary condition and improved image method can be applied to the two-phase medium wave equation to simulate the typical media model including horizontal layer and undulating interface, analyze the full wave information including the Rayleigh surface wave and body wave, and make a stability analysis. The results show that, on the basis of the comparison between the numerical solution and the analytical solution of the elastic media within the acceptable range of the error, the study of biphasic medium is feasible. The slight improvement of the image method can be applied to biphasic media to deal with free boundary condition problem of the Rayleigh surface wave effectively. The detailed analysis of the full wave field information of biphasic media including the Rayleigh surface wave and body wave shows that it has played a guiding role in the seismic exploration on the basis of biphasic media.
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