A novel wave equation solver to increase the efficiency of full waveform inversion

Summary Full waveform inversion (FWI) is a computationally demanding procedure to estimate the velocity model for seismic imaging. We develop a new method to reduce computational cost of FWI by approximating the gradient vector and Hessian matrix with the help of a new forward solver. The proposed solver is based on special interface conditions that facilitate sequential solution of the wavefield, which is a good approximation of that from full wave equation. The proposed approximation, when incorporated into FWI framework, does not affect the convergence and improves FWI efficiency.