Acoustic multi-parameter full waveform inversion based on the wavelet method.

In this paper, the acoustic full waveform inversion based on the wavelet method is proposed. It allows to determine density and velocity parameters simultaneously in the time domain. The forward problem is solved based on the wavelet method. The numerical schemes for modelling are constructed in detail. The stability condition is derived for the first time. The inversion is an optimization process for minimizing the mismatch between the synthetic data and the observed data. The computational scheme for the gradient of the objective function is constructed based on the matrix analysis technique. The inversion is implemented from low frequency to high frequency successively. Furthermore, the inversion result of current low frequency is served as the initial guess of next high frequency. This hierarchic strategy includes the smaller wavelengths progressively and improves the inversion robustness. Numerical computations for the benchmark Marmousi model demonstrate that the method has good ability to reconstruct media parameters in complex structures. [ABSTRACT FROM AUTHOR]