Author(s)

Wensheng Zhang^1,2*, Yijun Li^1,2

¹State Key Laboratory of Scientific and Engineering Computing, Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing, China.
²School of Mathematical Sciences, University of Chinese Academy Sciences, Beijing, China.

In this paper, we investigate the elastic wave full-waveform inversion (FWI) based on the trust region method. The FWI is an optimization problem of minimizing the misfit between the observed data and simulated data. Usually, the line search method is used to update the model parameters iteratively. The line search method generates a search direction first and then finds a suitable step length along the direction. In the trust region method, it defines a trial step length within a certain neighborhood of the current iterate point and then solves a trust region subproblem. The theoretical methods for the trust region FWI with the Newton type method are described. The algorithms for the truncated Newton method with the line search strategy and for the Gauss-Newton method with the trust region strategy are presented. Numerical computations of FWI for the Marmousi model by the L-BFGS method, the Gauss-Newton method and the truncated Newton method are completed. The comparisons between the line search strategy and the trust region strategy are given and show that the trust region method is more efficient than the line search method and both the Gauss-Newton and truncated Newton methods are more accurate than the L-BFGS method.

Elastic Wave Equations, Full-Waveform Inversion, Trust Region Strate-gy, Line Search Strategy, Newton-Type Method, Time Domain

Zhang, W. and Li, Y. (2021) Elastic Full Waveform Inversion Based on the Trust Region Strategy. American Journal of Computational Mathematics, 11, 241-266. doi: 10.4236/ajcm.2021.114016.