A new temporal high order and spatial implicit finite-difference scheme for acoustic wave modeling

Suppressing the numerical dispersion error is one of the key items for the finite-difference (FD) method. Usually, approximating the spatial derivatives by the implicit FD method is an effective approach to suppress the spatial dispersion for acoustic wave modelling. However, the temporal accuracy is still limited. To tackle this issue, we propose a new temporal high order and spatial implicit FD scheme. Based on this scheme, the corresponding time–space domain FD coefficients are generated by adopting a least-square algorithm. Our linear optimization strategy avoids difficulty of the non-linear optimization of the current spatial implicit and temporal high-order methods. Comparison of conventional implicit methods demonstrate the accuracy and efficiency superiority of our new linear optimized FD scheme.