Fig. 17From: Porosity–permeability relationship derived from Upper Jurassic carbonate rock cores to assess the regional hydraulic matrix properties of the Malm reservoir in the South German Molasse BasinComparison of porosity measured by HEP and WIP methods. a\(\phi_{\text{eff}}^{\text{w}}\) is directly plotted against \(\phi_{\text{eff}}^{\text{He}}\). Data were separated to control lithology dependency. Density plots show a positively skewed distribution and a high variance of porosity. B: Histogram and cumulative frequency of porosity deviation between both methods (bin width = 0.25%). Red dotted lines show 10% and 90% percentiles between which most deviation values were found. Blue dashed line indicates that 50% of all samples have a deviation of less than—0.9% p.u. and 50% more than—0.9% p.uBack to article page