Multiparameter Elastic FWI for Joint Inversion of Velocity and Reflectivity

We propose a multiparameter elastic FWI to simultaneously invert P-wave velocity and reflectivity. Our theoretical framework consists of two main elements for achieving this multiparameter inversion. First, we reformulate the system of waves equations parameterized in terms of P- and S-wave velocities as well as vector reflectivity. Second, we derive the sensitivity kernels for P-wave velocity and vector reflectivity using inverse scattering theory, which effectively reduce the crosstalk between parameters. We apply the algorithm to a dataset acquired in a complex salt environment in offshore Brazil. The results demonstrate the advantages of extending the multiparameter inversion approach to the elastic case compared to the acoustic version.