A simplified staggered-grid finite-difference scheme and its linear solution for the first-order acoustic wave-equation modeling

First-order staggered-grid finite-difference methods are widely used to synthesize seismograms theoretically. They are also the basis of least-squares reverse time migration and full waveform inversion. It is important to accelerate the wave-equation simulation while still preserving high accuracy. Usually the same staggered-grid finite difference operator is used for all of the first-order spatial derivatives in the first-order acoustic wave-equation. In this paper, we propose a simplified staggered-grid finite-difference scheme which uses different finite-difference operators for different first-order spatial derivatives in the first-order acoustic wave-equation. Because the new dispersion relation is linear, the staggered-grid finite-difference coefficients are determined in the time-space domain with the previously proposed linear method. We demonstrate by dispersion analysis and numerical simulation the efficiency of the proposed method.