Should We Move towards Multi-parameter Elastic Inversions?

In its standard least-square formulation, full waveform inversion aims at matching both the phases and the amplitudes of the recorded events. The dynamics of the seismic waves, especially of the reflection waves are of elastic nature. Moreover, earth parameter variations inside the first Fresnel zone induce interference patterns that may also be of elastic nature according to the diffraction theory. Since the Fresnel zone is inversely proportional to the square root of frequency, these interferences occur more at low frequencies. To account for this phenomenon, we may consider a more precise physics to describe the diffraction effects. During this presentation, I shall discuss multi-parameter inversion under the viscous acoustic and the elastic assumption to discuss the need to account for more precise physics.