Multicomponent multichannel analysis of surface waves for near-surface characterization
Abstract
Surface-wave analysis methods have been effectively and widely used to determine near-surface shear (S) wave velocity. We jointly analyze multicomponent surface waves to obtain relatively accurate S-wave velocity and radial anisotropy of near-surface media. Synthetic examples suggest Rayleigh-wave spectra extracted from vertical and radial components contain different dispersion energy. By joint analysis of vertical and radial components, the extracted Rayleigh-wave dispersion curves will be expanded in a wider frequency range, which can provide more information for the inversions. The horizontal to vertical spectral rato analysis method can also be applied to active Rayleigh waves after mode separation, which provides another way to estimate S-wave velocity. Love waves extracted from the horizontal component can be inverted for the horizontally polarized shear (SH) wave velocities (Vsh), which is different from the vertically polarized shear (SV) wave velocities (Vsv) inferred from Rayleigh waves. Based on the reliable Vsv and Vsh, the radial anisotropy can be obtained and analyzed for near-surface characterization. Results from synthetic and field data demonstrate that the joint analysis methods based on multicomponent surface waves will reduce the nonuniqueness and provide better constrained and more reliable S-wave velocity and radial anisotropy information in the shallow subsurface.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMNS34A..07M
- Keywords:
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- 4302 Geological;
- NATURAL HAZARDS;
- 4306 Multihazards;
- NATURAL HAZARDS;
- 4325 Megacities and urban environment;
- NATURAL HAZARDS;
- 4327 Resilience;
- NATURAL HAZARDS