Application of wavelet analysis of X-Ray computed tomography histogram for phase segmentation

Abstract

Abstract With the development of unconventional resources, the standard task of evaluation the porosity and oil saturation needs a new approach. Heavy oil and bitumen can act as the cement in many sand reservoirs, which excludes the use of standard measuring techniques. A method for phase segmentation and estimating the porosity and oil saturation of heavy oil reservoirs, based on wavelet analysis of X-ray computed tomography histogram was proposed. Its advantages are reducing human influence on phase thresholding and the ability to work with loose sand reservoirs, for which it is not possible to use standard assessment methods. The main problem found for this method is the need for high detailing of segmentation objects since a large amount of noise and transition voxels adversely affect class recognition and quantitative interpretation. The application of wavelet analysis approach for naturally heavy oil saturated samples requires high-resolution microCT (less than 5 µm) and high oil saturation of the samples.