Research on the Influence of Surface Wave Dispersion Curve in Anisotropic Viscoelastic Media

Abstract Surface-wave dispersion curve inversion of S-wave velocity structure is one of the primary methods for revealing near-surface structures. However, near-surface structures have large anisotropy and strong attenuation characteristics. Previous studies have investigated that surface anisotropy and sediment attenuation parameters significantly impact the extraction of dispersive information. Quantitatively assessing the sensitivity of different parameters can provide a reference for accurate inversion of S-wave velocity. In this abstract, we utilize a 2-D VTI viscoelastic finite-difference method to simulate the propagation characteristics and dispersion features of Rayleigh wave in anisotropic and viscoelastic media. Then, we use the typical synthetic model to analyze the sensitivity of Rayleigh wave dispersion curves to viscoelastic and anisotropic parameters. The conclusion is that the anisotropic and attenuation parameters cause significant changes in the surface-wave phase velocity, and the viscoelasticity can cause the amplitude attenuation of the Rayleigh wave. The sensitivity of dispersion curves to anisotropic parameters is greater than that of viscoelastic parameters.