“…In this article, we adopt the spectral-element method (SEM), which combines the accuracy of pseudospectral methods with the flexibility of the FEM, thereby providing key advantages in terms of computational performance (e.g., Tromp et al, 2008). If need be, the SEM can be implemented as a discontinuous Galerkin method (Kopriva et al, 2002;Kopriva, 2006;Acosta Minolia and Kopriva, 2011). The SEM has been used to study 2D and 3D local, regional, and global seismic-wave propagation problems (e.g., Cohen et al, 1993;Priolo et al, 1994;Faccioli et al, 1997;Komatitsch, 1997;Komatitsch and Vilotte, 1998;Komatitsch and Tromp, 2002a,b;Chaljub and Valette, 2004;Komatitsch et al, 2004Komatitsch et al, , 2005Liu et al, 2004;Stich and Morelli, 2007;Lee et al, 2008;Stich et al, 2009;Stupazzini et al, 2009;Tape et al, 2010;Zhu et al, 2012a,b).…”