It is estimated that massive hydrocarbon reserves (~60% oil and 40% gas at worldwide) are comprised in carbonate reservoirs. For example, the Middle East is dominated by carbonate fields in which about 70% of oil and 90% of gas reserves are stored within these reservoirs; in Brazil, carbonates are also important, by their substantial presence in pre- and post-salt reservoirs. However, carbonate characterization is a hard task, as they display high variability properties within small sections of the reservoir. A focused study is indicated, especially to better understand the heterogeneous nature observed in these rocks. In this work, pore space was investigated by two different approaches of digital image analysis (X-ray µ-CT and optical microscopy) to quantify pore properties and to promote discussions about data processing and differences between image resolutions. It allowed increasing the knowledge about pore system evaluation of middle-east carbonates.
Pore-system evaluation of Middle East carbonates using synchrotron x-ray µCT