| Summary: | Transport properties, such as permeability and electrical conductivity, are important in many
geophysical and petroleum applications. The microstructure of a porous medium and physical
characteristics of the solid and the fluids that occupy the pore space determine the macroscopic
transport properties of the medium. The computation of macroscopic properties from the rock
microtomography is becoming an increasingly studied topic. The transport properties are especially
difficult to determine at the microscopic scale. The purpose of this paper is to test the applicabilities to
numerically calculate the geometrical and transport properties (electrical conductivity, permeability,
specific surface area and surface conductivity) of porous, permeable rocks, given the digital CT
microtomography images. To better address the relationship between geometrical properties and
transport properties, we use a number of artificial low, medium- to high-porosity Finney’s (1970)
sphere packs. Numerically calculated transport properties are compared with analytical and empirical
equations on the Finney pack. In particular, numerically computed permeability on the Finney pack
agrees well with the permeability calculated from the computed formation factor using an empirical
relationship on the same structure. This illustrates the consistence of resolving different transport
properties on the same structure and the possibility of multiphysics coupling in the future. We also
apply all the numerical simulations on the 3D X-ray microtomography of 23.6% porosity Berea
Sandstone with 2.8 micron resolution. Numerical calculations of electrical conductivity, permeability
and specific surface area on mm[superscript 3] image will be compared to the laboratory measurements with those
parameters on cm[superscript 3] core samples. The upscaling issue will be discussed when we compare the
numerical results with laboratory measurements at a different scale. We also analyze the image
resolution impact on different properties to better understand the discrepancy between numerical
computations and laboratory measurements. This paper provides a complete work on the numerical
simulations on different physics at different scales. Numerical calculations are compared with analytic,
empirical rock physics equations and laboratory measurements.
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