Impacts of Mineralogy on Petrophysical Properties

Abstract Because of their extreme heterogeneity at multiple scales, carbonate rocks present a great challenge for studying and managing oil reservoirs. Depositional processes diagenetic alterations carbonates may have produced very complex pore structures and, consequently, variable fluid storage flow properties hydrocarbon To understand the impact mineralogy on system, we analyzed four rock samples (coquinas) from Morro do Chaves Formation in Brazil. For this study, used thin sections XRD mineralogical characterization, together with routine core analysis, NMR, MICP microCT petrophysical characterizations. The revealed similar porosity values but considerably different permeabilities. Samples relatively high quartz content (terrigenous material) generally had lower permeabilities, mostly caused by more mineral fragmentation. little or no turn exhibited permeabilities due to less fragmentation actions (e.g., dissolution shells). Results confirm that minerals are susceptible diagenesis, leading modifications body throat sizes, creating pores classified as moldic vug pores, even clogging them. one samples, acquired detailed skeleton information based images obtain complete understanding its structural characteristics.