Preconditioner for estimation of multipole sources via full waveform inversion

JOURNAL OF COMPUTATIONAL PHYSICS

卷:419

Article

Bencomo, Mario J.¹  Symes, William W.¹ 

[1] Rice Univ, Rice Invers Project, Houston, TX 77005 USA

关键词: Full waveform inversion;    Multipole source;    Preconditioning;    Conjugate gradient;    Ill-conditioned linear inverse problems;   

DOI  :  10.1016/j.jcp.2020.109667

来源: Elsevier

【 摘 要 】

Accurate representation and estimation of seismic sources is crucial to the joint medium-source full waveform inversion problem. We focus on the source estimation subproblem and its difficulties, where seismic sources are modeled by truncated series of multipoles. The source full waveform inversion formulation results in a highly ill-conditioned (potentially ill-posed) linear least squares problem which we attempt to solve iteratively via conjugate gradient. Our main contribution lies in developing a preconditioner to accelerate the performance of conjugate gradient on multipole source inversion. The proposed preconditioner consists of (fractional) time derivative/integral operators based on analytical solutions to the wave equation with multipole sources in an unbounded, homogeneous medium. Numerical results in 2D demonstrate that the conjugate gradient iterations are accelerated when incorporating the proposed preconditioning scheme. (C) 2020 Elsevier Inc. All rights reserved.

【 授权许可】

Free