Abstract：This paper adopts the finite-difference (FD) forward modeling algorithm with coupled Lebedev and standard staggered grid schemes for complex anisotropic media, which means that the Lebedev grid is used only inside the media with lower symmetry (such as TI media with titled symmetry axis, monoclinic anisotropy), while the standard staggered grid is used in other regions. This algorithm avoids the errors introduced by wavefield interpolation of standard staggered grid scheme and reduces the consuming on memory and computation of Lebedev scheme. On this basis, we present the high-order FD relations in the transitional region of the coupled scheme and a new method for interpolating variables. This high-order coupled scheme could efficiently control the reflection error and overall error produced by different types of wave incident to the coupling interface even with big space sampling interval. At the same time, it provides a geometric savings in memory and the computation time decreases as well, thereby simulating the peculiarities of the wavefield in heterogeneous anisotropic media with high efficiency and accuracy.
