Linearized scattering of surface waves on a spherical Earth

Main Article Content

R. Snieder
G. Nolet

Abstract

Recently, a formalism for three-dimensional surface-wave scattering in a plane geometry was derived. Since teleseismic surface-wave data are generally recorded at epicentral distances large enough to be influenced by the sphericity of the Earth, it is necessary to find the effects of a spherical geometry on surface-wave scattering. The theory of surface-wave scattering relies heavily on a dyadic decomposition of the Green's function, and a new derivation is given for the (dyadic) Green's function of a spherically symmetric Earth. This new derivation employs Poisson's sum formula and is more rigorous than previous derivations. Using the dyadic Green's function, a relation is established with the scattering theory in a flat geometry. This finally leads to a linearized formalism for three-dimensional surface-wave scattering on a sphere. Even for shallow surface waves the effects of sphericity are important and necessitate a modification of the propagator terms in the expression for the scattered surface waves.


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How to Cite
Snieder, R., & Nolet, G. (1987). Linearized scattering of surface waves on a spherical Earth. Journal of Geophysics, 61(1), 55-63. Retrieved from https://journal.geophysicsjournal.com/JofG/article/view/78

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