A K-Space Operator-based Temporal High-order Explicit FD Method for VTI and TTI Wave Equation

Abstract

Summary In this abstract, we develop a new spatial arbitrary even-order accuracy explicit FD method with higher accuracy to model the wave propagation in vertical transversely isotropic (VTI) and tilted transversely isotropic (TTI) media by using the k-space operator compensation. The high-order spatial FD coefficients are determined using plane-wave theory and k-space operator-based dispersion-relation. The new FD method has a lower temporal dispersion error than the conventional 2nd-order time domain FD method without increase the computational cost, so that a large time step is allowed to attain a similar accuracy. Numerical experiments in 2D VTI and TTI media with elliptical anisotropy demonstrate the superior accuracy of the new method. RTM using the new FD method shows its applicability in complex media. The new k-space operator-based explicit FD method can replace the conventional one to attain greater accuracy with a high efficiency in VTI and TTI media.