Inversion of Rayleigh Wave Dispersion Curves Considering the Sensitivities of Phase Velocities to S-wave Velocities

摘要

Rayleigh wave dispersion curves are often used to invert the S-wave velocities of the stratified halfspace.However,with former multi-mode inversion methods,the whole inverted result will be influenced if the error of a part of the measured dispersion curves is large.In this paper,by considering the sensitivities of phase velocities to S-wave velocities,a new multimode inversion method is presented,which is called classified inversion method.In this method,when inverting the S-wave velocities of the first several layers,the dispersion points that are not sensitive to the S-wave velocities of these layers will not be used.It can prevent the inversion result of some layers from being influenced by the error of the dispersion points that are not sensitive to their S-wave velocities.Inversion simulations are conducted and we found that the error of a part of the measured dispersion curves will only influence a part of the inverted result with our inversion method.