A new staggered grid finite difference scheme optimised in the space domain for the first order acoustic wave equation

Staggered grid finite difference (FD) methods are widely used to synthesise seismograms theoretically, and are also the basis of reverse time migration and full waveform inversion. Grid dispersion is one of the key problems for FD methods. It is desirable to have a FD scheme which can accelerate wave equation simulation while still preserving high accuracy. In this paper, we propose a totally new staggered grid FD scheme which uses different staggered grid FD operators for different first order spatial derivatives in the first order acoustic wave equation. We determine the FD coefficient in the space domain with the least-squares method. The dispersion analysis and numerical simulation demonstrated the effectiveness of the proposed method.