Comparison of the DG finite element method with finite difference method for elastic-elastic interface

In some seismic numerical applications we have to simulate wave propagation with sharp medium discontinuities. The rotated staggered grid (RSG) finite difference (FD) scheme and the arbitrary high-order derivatives discontinuous Galerkin (ADER-DG) finite element (FE) scheme can both be used for the problem of strong material heterogeneities. In this paper we study their behavior in a two-layer model with a varying ratio of the material parameters in the first layer to the second. We compared the results of the numerical schemes with the exact solution. The FD method and the FE method can both get small envelop misfits. The FE scheme has advantage over the FD method on phase misfits, but it needs a high CPU effort.