ELECTRIC FIELD RESPONSE OF TWO‐DIMENSIONAL INHOMOGENEITIES TO UNIPOLAR AND BIPOLAR ELECTRODE CONFIGURATIONS

Abstract

A quantitative comparative analysis of some bipolar and unipolar resistivity arrays is made in terms of perturbation effects due to buried lateral inhomogeneities. The Schlumberger, the collinear dipole‐dipole, the pole‐dipole, and the unipole electrode configurations of approximately the same dimensions are employed. A “focusing effect” in the vertical component of the current density distribution is demonstrated in the unipole configuration. Characteristic diagrams illustrating the configuration responses to lateral inhomogeneities located at different depths and under various overburden layer conductivities indicate that, for comparable geometric spreads, the unipole and the pole‐dipole configurations are significantly more effective.