High resolution imaging of the microstructure of Fontainebleau sandstone allows a direct comparison between theoretical calculations and laboratory measurements. While porosity, pore-volume-to-surface ratio, permeability, and end point relative permeability are well predicted by our calculations, we find that electrical resistivity and wetting phase residual saturation are both overestimated. Introduction Transport in porous media is of importance in biology, chemical engineering, earth and environmental sciences, materials science, and physics [Adler, 1992; Cushman, 1990]. Because real porous media are usually highly disordered, most recent work on transport theory has been based on synthetic model systems, such as random sphere packs [Adler, 1992; Schwartz et al., 1993]. Although instructive, such studies are not easily applied to the understanding of real materials. High resolution synchrotron microtomography [Flannery et al., 1987; Kinney et al., 1993; Schwartz et al., 1994; $panne eta!., 1994 Coles et al., 1995] however, may be used to map the pore space of a real material. Here we study the geometrical and transport properties of three-dimensional tomographic reconstructions of several samples of Fontainebleau sandstone. We compare numerical calculations to laboratory measurements made on samples approximately an order of magnitude larger in linear dimension. We obtain a heirarchy of results, presented in Table 1. Geometrical properties are accurately estimated by our calculations, as is the permeability to single-phase flow. The computed electrical conductivity, on the other hand, underestimates the experimental results. Studies of immiscible displacement by a non-wetting fluid give mixed results. While our endpoint relative permeability calculation is in good •Schlumberger-Doll Research, Ridgefield, CT. agreement with the measured data, the corresponding saturation is less satisfactory. AUZERAIS ET AL.: TRANSPORT IN SANDSTONE 707 2.0 ' -1.0 ß size 56 [] size 112 ¸ size 224 ß ß •e ß ß ß ee ß ß eee ß F. M Auzerais, T. S. Ramakrishnan, and L. M. Schwartz, Schlumberger-Doll Research, Ridgefield, CT 06877 J. Dunsmuir, Exxon Research and Engineering Company, Route 22 East, Annandale, NJ 08801 B. Ferr•ol, Elf Aquitaine,
