Finite Difference Modeling of Earthquakes

Understanding of strong earthquake motions includes the knowledge of wave propagation from source to receiver. Seismic elastic wave propagation is modelled on a large scale from the earthquake source through a heterogeneous earth to the receiver placed close to the infrastructure. Finite Difference techniques in two and three dimensions compute the full wave form solution to the wave propagation problem. The model size used in this example is 400kmx400kmx200km and source frequencies up to 2 Hz. The Finite Difference modeling software is written in High Performance Fortran and relies on on the SEPLIB processing package for Input/Ouput and parameter retrieval. A Large scale parallel machine proved to be necessary to be able to run realistic models and achieve acceptable turn-around time of modeling sequences for research purposes. The small modeling scenario in this paper demonstrates the practicality of modeling earthquake wave propagation realistically and shows that in the future it can be used in more elaborate modeling scenarios as they are planned for the Collaborative Research Project SFB 461 and other international collaborative research projects at Karlsruhe University.