On the Earthquake-Source Numerical Implementation in the Seismic Wave Equation

We present a detailed approach to implement a moment-tensor point source to compute displace- ments, particle velocities and accelerations using direct grid methods. Here, the wave modeling algorithm is based on pseudospectral methods to compute the partial derivatives. A comparison to the analytical solution in the 3D acoustic case verifies the discrete implementation of the source in the mesh. Then, the more general 3D elastic case is illustrated and simulations, with and without free surface, are performed that can be used as a reference solution for other grid methods.