Abstract

FERNANDES, Jaquiel Salvi; APPOLONI, Carlos Roberto  and  FERNANDES, Celso Peres. Determination of the Representative Elementary Volume for the study of sandstones and siltstones by X-Ray microtomography. Mat. Res. [online]. 2012, vol.15, n.4, pp. 662-670.  Epub July 31, 2012. ISSN 1516-1439.  http://dx.doi.org/10.1590/S1516-14392012005000081.

X-Ray computerized microtomography (µ-CT) besides providing two-dimensional images (2-D) of the transversal sections of the sample, the biggest attraction of the methodology is the rendering of three-dimensional images (3-D), enabling a more real analysis of the porous structure of the rock. However, the reconstruction, visualization and analysis of such 3-D images are limited in computer terms. Thus, it is not always possible to reconstruct the images with the total size of the microtomographed sample. Therefore, this study aims at determining the Representative Elementary Volume (REV) in reservoir rocks concerning their porosity. In order to collect microtomographic data from reservoir rocks, a microtomograph Skyscan model 1172 was utilized for the sandstone and siltstone samples scanning. After the analysis of the graphs obtained by REV, it was concluded that the most adequate dimensions for the reconstructed volume in each analyzed sample were approximately 1400 × 1400 × 1400 µm, which are dimensions that can easily be reconstructed, visualized and analyzed.

Keywords : representative elementary volume; X-ray microtomography; porosity; sandstone; siltstone.