Noise cross-correlation sensitivity kernels for Rayleigh wave ellipticity
Abstract
The ellipticity (H/V amplitude ratio) of Rayleigh waves is an unconventional surface wave observable that has been shown to exhibit enhanced sensitivity to Vp and density, compared to the traditional surface-wave dispersion measurements. 3-D sensitivity kernels for Rayleigh wave ellipticity have been recently developed for classical (e.g. earthquake-based) seismology but corresponding kernels for seismic ambient noise interferometry do not currently exist. We present sensitivity kernels for Rayleigh wave ellipticity under the framework of full wave interferometric theory for ambient noise. We extend a general treatment of cross correlations, without invoking relationships to the inter-station Green's tensor, so that the kernels obtained within this framework best represent the sensitivities of realistic measurements made using ambient noise. We compute kernels for Vp, Vs and density using a numerical (spectral element) implementation of the adjoint method, and compare them to the corresponding classical kernels. We also study how 3-D kernels are affected by anisotropic noise source distributions, which are naturally accounted for by full-wave interferometry.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.S42A..04D
- Keywords:
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- 0545 Modeling;
- COMPUTATIONAL GEOPHYSICS;
- 7260 Theory;
- SEISMOLOGY;
- 7270 Tomography;
- SEISMOLOGY;
- 7290 Computational seismology;
- SEISMOLOGY