A high-precision low-dispersive nearly analytic difference method with its application in frequency-domain seismic waveform inversion

Abstract

ABSTRACTTo improve the efficiency of seismic waveform inversion, we construct a novel high-order (6th-order) frequency-domain nearly analytic discrete method for forward modelling in inversion processes. Compared with some existing numerical schemes, this method is more powerful in suppressing numerical dispersion and enhancing the accuracy of computational results based on coarse discrete grids. We describe the discretisation of the frequency-domain wave equation, investigate the efficiency of wave-field simulation and perform numerical dispersion analysis. The inversion efficiency can also be improved when the inexact rotated block triangular preconditioned Krylov iteration solvers are incorporated into the corresponding linear system. Moreover, the inversion behaviour of frequency-domain NAD methods is also systematically discussed as one of its important applications. We take three representative media models as examples and the reliable inversion results are obtained reflecting the effectiveness of the proposed methods.