Patterns of porosity and permeability distribution in the Dibsiyah Member were analysed statistically. In general, the Member exhibits a limited range of porosity values and a wide range of permeability values. Histograms show that the porosity distribution of both Lower and Upper Units are approximately normal, and that their corresponding vertical and horizontal permeability distributions are positively skewed. The coefficient of variation for porosity in both the Lower and Upper Units is less than 0.5 indicating that the porosity range is small. However, the horizontal and vertical permeability values are more variable due to the spatial distribution of architectural elements and sedimentary structures within both units. The dissolution of unstable minerals, together with inhomogenous grain packing and poor connectivity, has resulted in a variable permeability distribution.