This study aims to characterize carbonate rocks outcrop with similar petrophysical properties of the Brazilian pre-salt by three different methodologies: Electrical Resistivity, Nuclear Magnetic Resonance (NMR) and Porosimetry by Mercury Intrusion (MICP) at room conditions. The rocks are coquinas from the Coqueiro Seco Formation at Sergipe Basin - Alagoas, Brazil, and Silurian dolomites from the Thornton formation, in United States. The rock samples were analyzed for varying brine / air / oil saturations by measuring electrical resistivity and magnetic transverse relaxation time (T2) at each level of saturation. Samples were also analyzed for throat size distribution using the technique of porosimetry by mercury intrusion (MICP). The relaxation time results show that the pore structures of the two carbonate rocks have pore size distributions of multimodal character. The coquinas and dolomites are composed mostly of macropores structures with a small fraction of micropores and mesopores. Nonetheless, the MICP results showed distinct distributions of pore throats. While coquinas present pore and throats of similar dimensions, dolomites have a significant amount of pores, mainly macropores, connected through restricting throats. The resistivity index curves for water/air saturations are typical, with a linear behavior, for both rocks. Coquinas kept a similar behavior when saturated with water and oil. However, dolomites tested with water/oil showed a double linear trend. The narrow throats seem to contribute to isolate water in the smaller pores at the lower range of water saturation.

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