Linearized elastic inversion of synthetic data from a gas-bearing sand model

Linearization is a goud approximation if the reference medium is sufficiently close to the actual one. The method we propose deals with a 1D reference medium and has been presented in Mace et al (1992). It is adapted to determine a 2D elastic target zone embedded in an almost laterally invariant elastic background. The method is based on the computation of the Jacobian matrix and uses a conjugate gradient algorithm to solve the optimization problem. In this paper, the linearized inversion method is valuated on synthetic prestack marine data from a gas-bearing sand model.