There have been recently substantial advances in Pore Scale Physics Discipline. These advances can now be used for the benefit of special core analysis (SCAL) measurements and interpretations. This paper is devoted to explain these improvements from two perspectives: (i) Pore scale imaging and network extraction (ii) Fluid flow modeling applied on the extracted networks in order to predict some key petrophysical properties (capillary pressures, relative permeabilities).

We use either thin sections or X-ray microtomograhy (micro-CT) to analyze rock cuttings of sandstones from Saudi Arabian oil and gas fields. These cuttings are a few mm across and are imaged with a resolution of 3 to 12 microns. Hence, the details of the three-dimensional pore space can be clearly seen. A maximal ball algorithm1,2  is used to extract a topologically equivalent pore-throat network: the largest inscribed spheres in the pore space representing the pores, with throats representing the connections between them.

In parallel to this algorithm, thin section images are utilized to build 3D equivalent images, reproducing porosity by a similar spatial variation of the grain sizes obtained from the thin sections. This has been done through the so called process based technique3  which is based on honoring the geological depositional mode of the rock.

The final aim is to input these network models into porescale fluid flow simulators to predict macroscopic properties such as relative permeability and capillary pressure. Blind tests are envisaged to compare the measured petrophysical properties and their corresponding numerical estimations.

This acts as a valuable complement to special core analysis, enabling predictions of properties – such as three phase relative permeabilities and the impact of wettability trends − outside the range probed experimentally.

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