FRACTAL DIMENSION DETERMINATION OF ROCK PORES BY MULTI-SCALE ANALYSIS OF IMAGES OBTAINED USING OM, SEM AND XCT

The present work includes the analysis of the porosity at different scales using image characterization techniques. Porosities were determined and compared for reservoir rocks through the fractal dimensions obtained from two-dimensional (2D) image analysis. Studies were developed using Optical Microscopy (OM), Scanning Electron Microscopy (SEM) and X-ray Computed Tomography (XCT). In order to compare the images and analyze the similarities in the porosities, the box-counting method was used to extract the power-law distributions and to obtain the fractal dimensions. Results showed that fractal dimensions were similar for the three different techniques, which included different scale analysis, fact that demonstrates the fractal character of the porosity in the studied systems. The effectiveness of the use of 2D image analysis and the importance of the multiscale study of the porosity were also demonstrated.