Induced polarization of shaly sands

Abstract

Equations have been developed that relate induced polarization (IP) in shaly sands to measurable petrophysical parameters. The induced‐polarization process has been modeled in terms of two mechanisms: clay counterion displacement and membrane blockage. The resulting equations can be used to determine shaliness, brine conductivity, and oil saturation from in‐phase and out‐of‐phase conductivities. Laboratory measurements have confirmed the IP dependence on these variables, as well as on temperature.