Abstract
Spherical coordinates are a natural orthogonal system for describing wavefronts emanating from a point source. A regular grid distribution in the Cartesian-coordinate system tends to undersample the wavefront description near the source (at the highest wavefront curvature) and oversample it away from the source. Spherical coordinates, in general, provide a more balanced grid distribution for characterizing point-source wavefronts. Our numerical implementation confirms that the recently introduced fast marching algorithm is both a highly efficient and an unconditionally stable eikonal solver. However, its first-order approximation of traveltime derivatives can induce relatively large traveltime errors for waves propagating in a diagonal direction with respect to the coordinate system. Examples, including the IFP Marmousi and the SEG/EAGE 3D salt-dome models, show that a spherical-coordinate implementation of the method results in far fewer errors in traveltime calculation than the conventional Cartesian-coordinate implementation, and with practically no loss in computational advantages.
Original language | English (US) |
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Pages (from-to) | 165-178 |
Number of pages | 14 |
Journal | Geophysical Prospecting |
Volume | 49 |
Issue number | 2 |
DOIs | |
State | Published - Mar 1 2001 |
Externally published | Yes |
Bibliographical note
Generated from Scopus record by KAUST IRTS on 2023-09-21ASJC Scopus subject areas
- Geochemistry and Petrology
- Geophysics