A technique to identify the predominant pore direction in a porous medium and application to reservoir rocks

Abstract

The study of the pore space structure of a porous medium has been very much improved with the aid of microtomographic imaging and its analysis through image processing. In this paper, a technique to identify the predominant pore direction (PPD) in the pore space is introduced and according to that the pore space can be partition as vertical (V), horizontal (H) or diagonal (D). The PPD technique has been developed for 2D and 3D spaces based on microCT images of a porous medium and can be used to both, pore or grain spaces. An implementation of the PPD has been done in an in-house computer program using Phyton. A set of application tests for 2D and 3D PPD partitioning is given, being, respectively, i) a synthetic binary image and a binary image of a Berea sandstone rock sample and ii) a Berea sandstone and a Carbonate reservoir rock core samples, both provided by the MicroCT Images and Networks of Imperial College London database, and a 3D grain partitioning of a trabecular bone structure. Additionally, the V, H and D PPD effective pore networks of a pore space are determined; the porosities for the PPD subspaces and for their effective pore networks are computed and results are provided. Finally, a brief discussion about the implementation and computational cost for the 2D and 3D cases is provided. It is worth to mention that the findings of this study may help for better understanding of directional fluid flow and mechanical stress in porous medium.