TY - JOUR
T1 - A multidomain approach of the Fourier pseudospectral method using discontinuous grid for elastic wave modeling
AU - Wang, Yanbin
AU - Takenaka, Hiroshi
N1 - Funding Information:
Acknowledgments. We are very grateful to Drs. P. Moczo and A. Pitarka for the critical reviews that significantly improved the manuscript. Careful reading and checking of the manuscript by Dr. R. Martin is appreciated. This study was partially supported by the comprehensive joint research project “Master model of strong motion prediction for mitigating earthquake disaster” funded by the coordination fund for promoting science and technology, Ministry of Education, Culture, Sports, Science and Technology of Japan.
PY - 2001
Y1 - 2001
N2 - Pseudospectral method is an efficient and high-accuracy numerical modeling technique that has been applied to the simulation of seismic wavefields in realistic models with complex structures such as sedimentary basin. However, if the sedimentary layers are included in the model, high velocity contrasts arise because of the very low S-wave velocities of the sediments as compared with the bedrock. The grid spacing then has to be very small, which leads to spatial oversampling in regions with higher velocities. As a result, we also have to use very small time interval for time marching, so that the computation requires much CPU time. A treatment of this problem is use of a multidomain approach that can employ different grid spacings in different regions, i.e. "discontinuous grid". In this study, we propose a scheme for the Fourier pseudospectral method using discontinuous grid, which uses an interpolation by the FFT. This scheme can reduce the computation time and the required computer memory as compared with the conventional one. The accuracy and efficiency of this approach are demonstrated in the present paper through examples of 2-D elastic wave modeling.
AB - Pseudospectral method is an efficient and high-accuracy numerical modeling technique that has been applied to the simulation of seismic wavefields in realistic models with complex structures such as sedimentary basin. However, if the sedimentary layers are included in the model, high velocity contrasts arise because of the very low S-wave velocities of the sediments as compared with the bedrock. The grid spacing then has to be very small, which leads to spatial oversampling in regions with higher velocities. As a result, we also have to use very small time interval for time marching, so that the computation requires much CPU time. A treatment of this problem is use of a multidomain approach that can employ different grid spacings in different regions, i.e. "discontinuous grid". In this study, we propose a scheme for the Fourier pseudospectral method using discontinuous grid, which uses an interpolation by the FFT. This scheme can reduce the computation time and the required computer memory as compared with the conventional one. The accuracy and efficiency of this approach are demonstrated in the present paper through examples of 2-D elastic wave modeling.
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U2 - 10.1186/BF03352372
DO - 10.1186/BF03352372
M3 - Article
AN - SCOPUS:20644451028
SN - 1880-5981
VL - 53
SP - 149
EP - 158
JO - Earth, Planets and Space
JF - Earth, Planets and Space
IS - 3
ER -