Numerical modeling of the coupled seismoelectric wave propagation in frequency domain

Mehran Gharibi, R. Arief Budiman, Robert R. Stewart, Laurence R. Bentley

Theoretical developments in the last decade suggest that seismoelectric responses are sensitive to the fluid content of the subsurface structures. The objectives of this study are to i) conduct theoretical and experimental studies to examine the properties of the coupled seismic and electromagnetic field disturbances in saturated porous media and ii) assess the potential of the seismoelectric and seismomagnetic techniques in detecting and evaluating deep structures such as hydrocarbon reservoirs. We describe our numerical modeling, in the frequency domain, of the generation of electromagnetic waves induced by seismic waves launched by surface explosions using FEMLAB. We have completed the frequency-domain simulations on a homogeneously porous semi-infinite solid. The three-dimensional simulations were based on three coupled partial differential equations involving the electric field, the solid-phase elastic displacement, and the relative displacement between the solid and the fluid phase. While the lateral components of the relative displacement do not appear to have any particular pattern, the resulting z-component of the electric field shows a macroscopic vertical dipole response. The solid-phase displacement agrees with the analytical results.