On Prediction of Permeability in Sedimentary Rocks Using Geoelectrical Parameters

Abstract Permeability prediction from geoelectrical measurements on sedimentary rocks remains a longstanding challenge due to the complex interplay between pore structure and electrical properties. This study investigates the relationship between permeability and geoelectrical parameters, particularly formation factor () and induced polarization (IP) measures, across a comprehensive database of 316 consolidated sedimentary rock samples. We define a “constrictivity exponent (),” related to the dependence of effective hydraulic pore radius on , and describing the resulting form of the permeability‐ relationship. The constrictivity exponent varies significantly across formations due to differences in the pore network that arise from geological processes such as compaction and cementation. While IP‐derived length‐scale proxies, including polarization strength and relaxation time, offer theoretical potential for improving permeability predictions, our results provide evidence that their practical utility is limited. Relaxation time‐based proxies are ineffective due to large variability in diffusion coefficients, and polarization strength‐based proxies only marginally improve predictions when formation‐specific parameters are applied. The formation factor alone remains the most robust predictor of permeability, with the constrictivity exponent providing essential context for model calibration. These findings underscore the importance of formation‐specific calibration and suggest that, without independent constraints on the constrictivity exponent, geoelectrical‐based permeability prediction may be unreliable.