Nonuniform 3D finite difference elastic wave simulation on staggered grids
Type
Article
KAUST Department
Applied Mathematics and Computational Science ProgramExtreme Computing Research Center
Computer, Electrical and Mathematical Science and Engineering (CEMSE) Division
Office of the President
KAUST Grant Number
OSR-2019-CCF-3666.4Date
2022-03-29Permanent link to this record
http://hdl.handle.net/10754/676318Metadata
Show full item recordAbstract
We present an approach to simulate the 3D isotropic elastic wave propagation using nonuniform finite difference discretization on staggered grids. Specifically, we consider simulation domains composed of layers of uniform grids with different grid spacings, separated by nonconforming interfaces. We demonstrate that this layer-wise finite difference discretization has the potential to significantly reduce the simulation cost, compared to its fully uniform counterpart, by more than an order of magnitude on geophysically representative 3D problems. Stability of such a discretization is achieved by using specially designed operators, which are variants of the standard finite difference operators with adaptations near boundaries or interfaces, and penalty terms, which are appended to the discretized wave system to weakly impose boundary or interface conditions. Combined with specially designed interpolation operators, the discretized wave system is shown to preserve the energy conserving property of the continuous elastic wave equation, and a fortiori ensure the stability of the simulation. Numerical examples are presented to demonstrate the efficacy of the proposed simulation approachCitation
Gao, L., Ghattas, O., & Keyes, D. (2022). Nonuniform 3D finite difference elastic wave simulation on staggered grids. GEOPHYSICS, 1–79. https://doi.org/10.1190/geo2021-0512.1Sponsors
The authors thank the editors and referees for carefully reviewing this article and providing valuable suggestions. This research used resources of the Core Labs of King Abdullah University of Science and Technology (KAUST). This research was funded by KAUST award OSR-2019-CCF-3666.4 and U.S. National Science Foundation Frontera award 2033468.Publisher
Society of Exploration GeophysicistsJournal
GEOPHYSICSAdditional Links
https://library.seg.org/doi/10.1190/geo2021-0512.1Scopus Count
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