1887

Abstract

Summary

Degeneracies of the slowness surfaces of quasi shear (and quasi compressional) waves in low-symmetry anisotropic media (such as orthorhombic), known as point singularities, pose difficulties during modeling and inversion, but can be potentially used in the latter as model parameters constraints. We analyze the relation between anisotropy strength and the number and distribution of singularities in orthorhombic media. Numerical experiments demonstrate that in weakly anisotropic media, only three patterns of the singularity locations are allowed, and it is impossible to encounter models with zero or maximum number of singularities unless shear stiffnesses are larger than compressional stiffnesses. Depending on the anisotropy strength, the off-plane singularities follow closed and non-intersecting trajectories.

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/content/papers/10.3997/2214-4609.201801059
2018-06-11
2020-04-10
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References

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