Porosity and Permeability Effects on the Seismo-Electric Reflection

4 Coupling between SH-waves and TE-waves When a horizontally polarized shear wave (SH-mode) propagates in the�-�plane its propagation is not coupled to the other three seismic wavefields (the fast and slow P-waves and the vertically polarized shear wave); however the SH-wave generates electric currents in the�-direction and these currents couple to the electromagnetic wavefield with transverse electric polarization (TEmode). As already shown by Haartsen and Pride (1997) this SHTE-coupling is represented by the set matrix� of differential equations given by Eq. (10). The system in Eq. (10) can be used to determine the velocities of the SH-wave and TE-wave in