Pseudospectral-element modelling of elastic waves in Matlab®

Matt A. D. McDonald, Michael P. Lamoureux, Gary F. Margrave

Numerical modelling of elastic waves is an integral part of many procedures in seismic imaging. As such it is important to have a fast and efficient algorithm that can properly model the underlying physics of elastic waves propagating in the subsurface of the earth. Because the inherent layering of the subsurface, an appropriate numerical method must take into account the level of continuity present in the underlying assumptions of the physical model. Failure to do so can result in reflected waves with incorrect phase and amplitudes. A convenient place to explore the properties of numerical methods is in the Matlab computing environment. In this paper we build a Pseudospectral-element method for the elastic wave equation in two spatial dimensions with second-order absorbing boundary conditions using the sparse data structure in Matlab with explicit time-stepping.