Spectral elements for very large offshore acoustic-elastic wave simulations

The Spectral Element Method (SEM), widely used in engineering sciences but almost unknown in Oil&Gas exploration, is a numerical technique for large scale and multi-physics simulations. SEM is an h-p approximation of the problem solution that allows a quasi-optimal distribution of computational points on unstructured grids so as to reduce both memory usage and processing time. Thus, when accuracy is mandatory in complex 3D geometries, SEM becomes an excellent alternative to Finite Elements (FE) and Finite Differences (FD). Its implementation on the elemental domain discretization, taking advantage of data locality, presents perspectives of significant speedups on acceleration architectures. Our SEM application is designed for the simulation of acoustic/elastic waves traveling across 3D subsurface models with liquid-solid interfaces and is capable of dealing with anisotropic and non-linear solid materials. In this work, some details of our SEM implementation and its HPC infrastructure are illustrated together with some simulation results.