Global seismic wave propagation simulation

Contributors from ICES, The University of Texas at Austin: Carsten Burstedde, Omar Ghattas, James R. Martin, Georg Stadler, Lucas C. Wilcox Visualization by Gregory D. Abram, Texas Advanced Computing Center, The University of Texas at Austin. Abstract: Modeling the propagation of seismic waves through the earth is an essential first step to inferring the structure of earth's interior. The propagation of waves through the oceans and outer core is modeled with the acoustic wave equation, while the elastic wave equation is employed for the crust, mantle, and inner core. We create a computational mesh in parallel by partitioning the earth into warped hexagonal elements whose size is adapted to the local seismic wavelengths. We employ a highly parallel and scalable discontinuous Galerkin method to discretize the governing elastodynamics equations on the adapted mesh. The mesh is partitioned for parallel execution using a space-filling curve. The visualization corresponds to a simulation with a central source frequency of 1/85 Hz and contains about 100 million degrees of freedom. Acknowledgements: This work was supported by AFOSR grant FA9550-09-1-0608 and NSF grants CMS-1028889 and DMS-0724746. Computing time on TACC's Lonestar 4 system was provided by an allocation from TACC.