Using DIRECT to invert high-frequency Rayleigh wave phase velocities
Inversion of high-frequency Rayleigh wave phase velocities is challenging for most local-search methods due to its high nonlinearity and to its multimodality.In this paper,we implemented and tested a Rayleigh wave dispersion curve inversion scheme based on DIRECT,a deterministic sampling algorithm that balances local and global search to overcome its slow convergence and to avoid its wandering neighborhood the global minimum in the final stage of search.The proposed inverse procedure was applied to nonlinear inversion of fundamental-mode Rayleigh wave dispersion curves for near-surface shear (S)-wave velocity profiles.The calculation efficiency and stability of the inversion scheme are tested on a four-layer synthetic model and a real example from Southern China.Results from both synthetic and actual field data demonstrate that the DIRECT algorithm applied to nonlinear inversion of high-frequency surface wave phase velocities should be considered good not only in terms of accuracy but also in terms of computation effort due to its global and deterministic search process.
surface waves Rayleigh waves dispersion curves lipschitzian optimization DIRECT
Xianhai Song Hanming Gu
Institute of Geophysics and Geomatics,China University of Geosciences,Wuhan 430074,China
国际会议
The 3rd International Conference on Environmental and Engineering Geophysics(第三届环境与工程地球物理国际会议)
武汉
英文
134-137
2008-06-15（万方平台首次上网日期，不代表论文的发表时间）