December 8th, 2003
An accurate understanding of the propagation of seismic waves in the Earth is of fundamental importance for Earth Scientists at any level. Wave propagation is generally difficult to understand due to the spherical geometry and strong compositional layering in the Earth. 3D heterogeneity, anisotropy and attenuation create further complexities. Several tools exists that help beginning and advanced geoscientists by visualizing wave propagation in the Earth for 1D velocity models. A recently developed spectral element method (SPECFEM3D; Komatitsch et al., Science, 298,1737, 2002) solves the full wave equation in a 3D spherical Earth which allows the inclusion of more realistic effects such as 3D heterogeneity and anisotropy.
Accurate models require high spatial and temporal resolution and the use of this code is therefore restricted to moderately large PC clusters or other parallel platforms. High resolution also presents difficulties when attempting to visualize wave propagation since the presence of high frequency information requires high spatial resolution in the visualization.
We have developed various approaches to visualizing realistic wave propagation, using both 2D slices and 3D volumes, at high resolution. The visualization tools will benefit researchers that use SPECFEM3D since it provides mechanisms of quality control, data querying and dissemination, while also allowing sharing new computational results with students and the media. We will demonstrate and compare visualizations for a number of historical earthquakes and provide a preliminary report on how students in introductory and advanced geophysics courses appreciated the use of these tools.
van Keken, P., Tromp, J., Komatitsch, D., Venkataraman, S., Schwarz, N., Renambot, L., Leigh, J., Visualizing Seismic Wave Propagation, Eos. Trans. AGU, 84(46), Fall Meet. Suppl., Abstract ED31E-01, December 8th, 2003.