Full Waveform Inversion of Viscoelastic Media Based on P–S Separation

Abstract

In viscoelastic full waveform inversion, there is interference between the gradients of the P- and S- wave velocities, leading to the degradation of the inversion accuracy. Therefore, the interference problem in viscoelastic media needs to be solved beforehand. Even though the P-S separation method has been demonstrated to be effective in reducing the crosstalk in elastic media, little attention has been paid to its efficacy in viscoelastic media. We incorporate the P-S separation method in the full waveform inversion of viscoelastic media (QEFWI) and derive a gradient formula for the QEFWI. Numerical tests on the QEFWI demonstrate that the proposed method can successfully reduce the interference problem between the gradients of P- and S- wave velocities, resulting in significant improvement of the viscoelastic full waveform inversion.