Time-Versus Frequency-Domain Modelling of Seismic Wave Propagation

E-15 TIME- VERSUS FREQUENCY-DOMAIN MODELLING OF SEISMIC WAVE PROPAGATION Abstract 1 Realistic three-dimensional elastic modelling is feasible though still costly on present-day parallel computers when using time-domain finite-difference methods. Frequency-domain methods are competitive for two-dimensional problems although the gain in speed is not sufficiently dramatic to justify the increase in code complexity. In three dimensions iterative solvers appear to be necessary. We report some experiments with BICGSTAB2 and a preconditioner based on separation of variables. These show unacceptable performance degradation for higher frequencies. Still frequency domain methods may be attractive for migration and inversion if only a reduced number of