Abstract
Equations are presented to determine the phase shift of the amplitude of the elastic Green tensor due to both simple (line) and point caustics in anisotropic media. The phase-shift rules for the Green tensor are expressed in terms of the paraxial-ray matrices calculated by dynamic ray tracing. The phase-shift rules are derived both for 2×2 paraxial-ray matrices in ray-centred coordinates and for 3×3 paraxial-ray matrices in general coordinates. The reciprocity of the phase shift of the Green tensor is demonstrated. Then a simple example is given to illustrate the positive and negative phase shifts in anisotropic media, and also to illustrate the reciprocity of the phase shift of the Green tensor.
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Klimeš, L. Phase shift of the Green tensor due to caustics in anisotropic media. Stud Geophys Geod 54, 269–289 (2010). https://doi.org/10.1007/s11200-010-0014-x
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DOI: https://doi.org/10.1007/s11200-010-0014-x