A new universal permeability model derived from mercury capillary pressure data

Abstract

This paper presents the construction and verification of a new better semi-analytical, statistically derived universal model than that modified from Huet and Blasingame equation for estimating absolute permeability from mercury injection capillary pressure data. The foundation of my new model is the petrophysical relation between absolute permeability and capillary pressure/wetting phase saturation properties. I also incorporate the characteristics of capillary pressure behavior using the classic Brooks-Corey power-law model. The final form of my new proposed model allows us to predict absolute permeability as a function of effective porosity, irreducible wetting phase saturation, displacement or threshold pressure corresponding pore-throat radius, and basic pore size characteristics. I built my model using 189 sets of mercury-injection (Hg-air) capillary pressure data and measured permeability including core samples from several reservoirs both carbonate and sandstone lithologies. I identified this correlation by quantifying its accuracy and precision based on regression analysis. I compare permeability estimates obtained from Huet and Blasingame mercury-injection capillary pressure-based model and my new universal predicted permeability model to a set of laboratory measured permeability of my studied core sample and previously published data results, respectively, where I quantifying the method's accuracy and precision based on error analysis. The measured permeability samples range is from 0.003 to 5,341 md. I review current employed models that are classified as belonging to Poiseuille model.