A Multi-parameter Full Waveform Inversion Strategy in Acoustic Media

Full waveform inversion (FWI) is a challenging data-matching procedure that exploits the full information from the seismic data to obtain high-resolution models of the subsurface. To best fit the observed seismograms, the forward modeling should correctly account for the wave propagation phenomena present in the recorded data, especially for the wide-aperture acquisition geometry. Thus, the mono-parameter acoustic FWI should be extended to multi-parameter FWI, such as P-wave velocity, shear-wave velocity, density, attenuation, anisotropy, or other related parameters.

In this study, we propose a multi-parameter full waveform inversion strategy that can simultaneously recover the velocity and density in acoustic media. The strategy consists of two stages and the acoustic wave equation is parameterized by velocity and density. In the first stage, the velocity and density are simultaneously inverted. In this case, the inverted velocity is reasonable while the density profile is deviated from the true one. During the second stage, the recovered velocity model in the first stage is reused as the initial velocity model. Then, the velocity and density are reconstructed at the same time. The final results show that both the velocity and density are reconstructed well. The synthetic numerical examples prove the validity of the method.