Electroseismic wave properties

In a porous material saturated by a fluid electrolyte, mechanical and electromagnetic disturbances are coupled. The coupling is due to an excess of electrolyte ions that exist in a fluid layer near the grain surfaces within the material; i.e., the coupling is electrokinetic in nature. The governing equations controlling the coupled electromagnetic-seismic (or ''electroseismic'') wave propagation are presented for a general anisotropic and heterogeneous porous material. Uniqueness is derived as well as the statements of energy conservation and reciprocity. Representation integrals for the various wave fields are derived that require, in general, nine different Green's tensors. For the special case of an isotropic and homogeneous wholespace, both the plane-wave and the point-source responses are obtained. Finally, the boundary conditions that hold at interfaces in the porous material are derived. (C) 1996 Acoustical Society of America.