Waveform inversion of shallow seismic refraction data using hybrid heuristic search method
Mika Takekoshi 1 Hiroaki Yamanaka 1 21 The Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, Kanagawa 226-8503, Japan.
2 Corresponding author. Email: yamanaka@depe.titech.ac.jp
Exploration Geophysics 40(1) 99-104 https://doi.org/10.1071/EG08113
Submitted: 6 September 2008 Accepted: 14 January 2009 Published: 27 February 2009
Abstract
We propose a waveform inversion method for SH-wave data obtained in a shallow seismic refraction survey, to determine a 2D inhomogeneous S-wave profile of shallow soils. In this method, a 2.5D equation is used to simulate SH-wave propagation in 2D media. The equation is solved with the staggered grid finite-difference approximation to the 4th-order in space and 2nd-order in time, to compute a synthetic wave. The misfit, defined using differences between calculated and observed waveforms, is minimised with a hybrid heuristic search method. We parameterise a 2D subsurface structural model with blocks with different depth boundaries, and S-wave velocities in each block. Numerical experiments were conducted using synthetic SH-wave data with white noise for a model having a blind layer and irregular interfaces. We could reconstruct a structure including a blind layer with reasonable computation time from surface seismic refraction data.
Key words: generic algorithm, heuristic search method, seismic refraction data, simulated annealing, waveform inversion.
Acknowledgments
The comments from two reviewers are appreciated to improve the manuscript. The authors acknowledge financial support from Japan Ministry of Education, Culture, Sport, Science, and Technology (MEXT).
Aoi, S., Iwata, T., Irikura, K., and Sanchez-Sesma, F. J., 1995, Waveform Inversion for Determining the Boundary Shape of a Basin Structure: Bulletin of the Seismological Society of America 85, 1445–1455.
Gao, F., Levander, A., Pratt, R. G., Zelt, C. A., and Fradelizio, G.-L., 2007, Waveform tomography at a groundwater contamination site: Surface reflection data: Geophysics 72, G45–G55.
| Crossref | GoogleScholarGoogle Scholar |
Pratt, R. G., Shin, C., and Hicks, G. J., 1998, Gauss-Newton and full Newton methods in frequency seismic waveform inversion: Geophysical Journal International 133, 341–361.
| Crossref | GoogleScholarGoogle Scholar |
Sen, M. K., Bhattacharya, B. B., and Stoffa, P. L., 1993, Nonlinear inversion of resistivity sounding data: Geophysics 58, 496–507.
| Crossref | GoogleScholarGoogle Scholar |
Sheng, J., Leeds, A., Buddensiek, M., and Schuster, G. T., 2006, Early arrival waveform tomography on near-surface refraction data: Geophysics 71, U47–U57.
| Crossref | GoogleScholarGoogle Scholar |
Yamanaka, H., and Ishida, H., 1996, Application of genetic algorithms to an inversion of surface-wave dispersion data: Bulletin of the Seismological Society of America 86, 436–444.
Yamanaka, H., 2005, Comparison of performance of heuristic search methods for phase velocity inversion in shallow surface wave methods: Journal of Environmental & Engineering Geophysics 10, 163–173.
| Crossref | GoogleScholarGoogle Scholar |
Yamanaka, H., 2007, Inversion of surface-wave phase velocity using hybrid heuristic search method: Butsuri Tansa 60, 265–275.