Wave-equation surface waves dispersion inversion in vertical transverse isotropic media

Abstract

The wave-equation dispersion inversion (WD) method is a robust approach for reconstructing the S-wave velocity structure, which does not require the assumption of layered media and is independent of source wavelets. However, theoretical analysis demonstrates that surface wave dispersion curves are sensitive to anisotropic parameters. Conventional WD is based on isotropic media, neglecting the anisotropic characteristics of the subsurface structure. To correct and evaluate the anisotropy effect, we present the theory for anisotropic Love wave-equation dispersion inversion (LWD) method based on the vertical transverse isotropic media (VTI-LWD). The synthetic and field data demonstrate that the proposed VTI-LWD significantly improves the accuracy of the S-wave velocity model while simultaneously estimating the anisotropic parameter. This provides more accurate multi-parameter information for near-surface stratigraphic structures.