Electrical Resistivity Measurement with Spherical-Tipped Cylindrical Electrode Embedded on Two Layers

Materials (Basel). 2020 May 6;13(9):2144. doi: 10.3390/ma13092144.

Abstract

Complex geological processes form multiple layers and change pore water chemistry, saturation level, and temperature. Eventually, the strata hinder interpreting electrical resistivity data. There are no studies that theoretically explore the effects of electrode geometries and multiple layered systems on laboratory electrical resistivity measurements. This study formulates a theoretical electrical resistance between half spherical-tipped cylindrical electrodes embedded on two horizontal layers. The electrical resistivity of each layer is considered separately in the general electrical potential equation with different equipotential surface areas. The finite element analysis is conducted to validate the theoretical equation. Further interpretation provides insights into the distribution of electrical current flow under electrical resistivity mismatch for discussion.

Keywords: cylindrical electrodes with spherical tip; electrical resistivity; electrical resistivity mismatch; layered medium; penetration depth; upper layer thickness.