Integrated petrographical and petrophysical studies of sandstones from the Araba Formation for reservoir characterization

Abstract The present study aims at an integration of both petrographic and petrophysical data 45 sandstone samples collected from Araba Formation (Lower Paleozoic) for reservoir characterization. studied is classified into three types facies: (i) quartz arenite, (ii) sublithic (iii) calcareous arenite. mineralogical composition the includes mainly detrital clays, some pyrite, iron oxides as cement. investigation reveals various diagenetic processes including compaction pressure solution, cementation with oxides, carbonates, or clays. porosity values investigated range 14.5 to 27.8% permeability 2.4 mD 8.4 D, surface area per unit pore volume ( S por ) 0.011 17 µm −1 , formation factor 6 13, dimensionless volumetric magnetic susceptibility 13 10 −6 126 . facies are characterized by higher permeability. indicate increasing rising porosity. relationship between reflects effect changes. specific shows inverse investigations provide relationships other parameters such porosity, factor, surface, longitudinal transverse relaxation time resulting nuclear resonance (NMR) relaxometry. prediction model based on NMR proves be applicable (ii), whereas predictive quality considerably lower (iii).