Joint inversion of high-frequency surface waves with fundamental and higher modes

Y. Luo; J. Xia; J. Liu; Q. Liu; S. Xu

doi:10.1016/j.jappgeo.2007.02.004

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Joint inversion of high-frequency surface waves with fundamental and higher modes

Y. Luo·J. Xia·J. Liu·Q. Liu·S. Xu

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Abstract

Joint inversion of multimode surface waves for estimating the shear (S)-wave velocity has received much attention in recent years. In this paper, we first analyze sensitivity of phase velocities of multimodes of surface waves for a six-layer earth model, and then we invert surface-wave dispersion curves of the theoretical model and a real-world example. Sensitivity analysis shows that fundamental mode data are more sensitive to the S-wave velocities of shallow layers and are concentrated on a very narrow frequency band, while higher mode data are more sensitive to the parameters of relatively deeper layers and are distributed over a wider frequency band. These properties provide a foundation of using a multimode joint inversion to define S-wave velocities. Inversion results of both synthetic data and a real-world example demonstrate that joint inversion with the damped least-square method and the singular-value decomposition technique to invert high-frequency surface waves with fundamental and higher mode data simultaneously can effectively reduce the ambiguity and improve the accuracy of S-wave velocities. ?? 2007.

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Y. Luo, J. Xia, J. Liu, Q. Liu, S. Xu. 2007. Joint inversion of high-frequency surface waves with fundamental and higher modes. https://doi.org/10.1016/j.jappgeo.2007.02.004

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