Efficient Two-Dimensional Anisotropic Ray Tracing
Attempts to model synthetic data in anisotropic media often encounter severe difficulties. Specifically, the complexity of the mathematical description of wave propagation in anisotropic media limits most existing software to treating simple models (such as horizontal layers); alternative methods are mainly based on computationally inefficient algorithms.
Combining a ray-theoretical method with a two-dimensional model representation based on Delaunay triangulation helps to partially overcome these difficulties and allows efficient computations even in models of pronounced structural complexity. To obtain analytic solutions for the ray propagation, we assume elastic parameters to be constant in each triangle. Thus, while the overall structure can be complex, ray tracing is simple and efficient in each triangular cell.
Another challenge is that of explaining anisotropy to the general geophysical community. Ray tracing has been eminently capable of enhancing the understanding of how seismic waves propagate in anisotropic velocity fields, where physical intuition based on isotropy often fails. The display of raypaths and wavefronts is an educating tool to characterize and describe seismic phenomena including energy focusing and defocusing and the formation of wavefront triplications.
Figures & Tables
“This volume contains a set of papers based on presentations given at the Sixth International Workshop on Seismic Anisotropy.”