Anisotropy vertical variation

Finally, Kirkwood Crampin (1981) showed that particle-motion anomalies are diagnostic of anisotropy and that the variations with period can be used to estimate the approximate depth of the anisotropic layer. This is best done using fundamental quasi-Love waves visible on the radial and vertical components, as they will not be contaminated by the later arriving Rayleigh waves (Yu Park 1994). 

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