Assessing the representative elementary volume of rock types by X-ray computed tomography (CT) – a simple approach to demonstrate the heterogeneity of the Boda Claystone Formation in Hungary

Abstract X-ray computed tomography (CT) can reveal internal, three-dimensional details of objects in a non-destructive way and provide high-resolution, quantitative data the form CT numbers. The sensitivity number to changes material density means that it may be used identify lithology within cores sedimentary rocks. present pilot study confirms use Representative Elementary Volume (REV) quantify inhomogeneity densities rock constituents Boda Claystone Formation. Thirty-two layers, 2 m core length, this formation were studied. Based on dominant rock-forming constituent, two types could defined, i.e., clayey siltstone (20 layers) fine (12 layers). Eleven these layers (clayey siltstone) showed features such as, convolute laminations, desiccation cracks, cross-laminations cracks. application Autoregressive Integrated Moving Averages, Statistical Process Control (ARIMA SPC) method define (Hounsfield unit values) affirmed following results: i) highest REV values corresponded presence structures or high ratios (> 60%). ii) average was (5.86 cm 3 ) (6.54 siltstone. iii) normalised percentages siltstone, scale volume studied 19.88% 22.84%; respectively. iv) whenever corresponding layer did not any structure, would below 10%. internal void space with might explain marked textural heterogeneity elevated values. drying process sample also have played significant role increasing erroneous pore proportions by reducation clay minerals, particularly structures, where authigenic carbonate cement presumed dominant.