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Application of high-resolution linear Radon transform for Rayleigh-wave dispersive energy imaging and mode separating

Y. Luo·J. Xia·R. D. Miller·J. Liu·Y. Xu·Q. Liu
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Abstract

Multichannel Analysis of Surface Waves (MASW) analysis is an efficient tool to obtain the vertical shear-wave profile. One of the key steps in the MASW method is to generate an image of dispersive energy in the frequency-velocity domain, so dispersion curves can be determined by picking peaks of dispersion energy. In this paper, we image Rayleigh-wave dispersive energy and separate multimodes from a multichannel record by high-resolution linear Radon transform (LRT). We first introduce Rayleigh-wave dispersive energy imaging by high-resolution LRT. We then show the process of Rayleigh-wave mode separation. Results of synthetic and real-world examples demonstrate that (1) compared with slant stacking algorithm, high-resolution LRT can improve the resolution of images of dispersion energy by more than 50% (2) high-resolution LRT can successfully separate multimode dispersive energy of Rayleigh waves with high resolution; and (3) multimode separation and reconstruction expand frequency ranges of higher mode dispersive energy, which not only increases the investigation depth but also provides a means to accurately determine cut-off frequencies.

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Y. Luo, J. Xia, R. D. Miller, J. Liu, Y. Xu, Q. Liu. 2008-12-15. Application of high-resolution linear Radon transform for Rayleigh-wave dispersive energy imaging and mode separating. https://doi.org/10.1190/1.3059376

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