Green’s Functions for Moment Tensor Sources Including the Double Couple Source

We study the seismo-electromagnetic waves radiated by an earthquake fault slip in a saturated porous medium arising from the electrokinetic effect. The earthquake source is modeled by a double couple point source. Using Pride’s equations, we derive the Green’s functions of the solid displacement, the electric and magnetic fields excited by moment tensor sources. The radiation patterns of the electric and magnetic fields are calculated and displayed, showing they are direction-dependent. We also calculate the waveforms of the solid displacement, electric and magnetic fields. The result shows that there are the electric fields accompanying both the P and S waves, as well as the magnetic field accompanying the S wave. Besides, there is an independently propagating electromagnetic wave, which arrives at the observation site immediately after the source launched.