Scattering of SH waves by a spherical layer

In the frame work of the theory of classical elasticity we study the interaction of spherical elastic SH waves of harmonic type with a spherical layer when the source is placed outside the layer. The exact solution of this scattering problem is investigated in detail after a generalized Debye's expansion is established. The presence of the spherical layer is evident from the second term of this development. The interpretations obtained for a one-sphere model remain valid. However, among the differences we note that the surface waves created on the outer face of the layer rise or die out according to an angle which depends on the mechanical and geometrical features of the layer.