Parallel 3-D Simulation of Ground Motion for the 1995 Kobe Earthquake: The Component Decomposition Approach

A new approach to parallel pseudospectral simulation of 3-D seismic wave propagation is developed based on component decomposition of the wavefield. Field quantities and equations of motion are distributed over three processors according to their relationship to the x-, y- and z-coordinates, and computation is carried out concurrently on each processor with inter-processor communications. The efficiency of this approach is evaluated by a theoretical estimate and actual benchmark computations. We then conduct a 3-D simulation of strong ground motion for the 1995 Kobe (Hyogo-ken Nanbu) earthquake in order to show the feasibility of the parallel pseudospectral method. The results of the simulation demonstrate that the complex 3-D structures of the subsurface medium and source fault greatly affect the strong ground motion on the surface.