Fig. 7From: 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 BasinThin sections of Jurassic carbonate rocks from the Dingolfing FB rock core. a Fossiliferous grainstone of Malm ζ 4–5 section containing peloids and abundant fragments of green algae Clypeina jurassica (CJ) and Campbelliella striata (CS). Note interparticle porosity (blue staining) cumulating to \(\phi_{\text{eff}}^{\text{w}}\) of 13.0% for the whole sample. b Same rock type and strata than in a but pore space is reduced by sparitic cementation (arrows) between particles. (\(\phi_{\text{eff}}^{\text{w}} = 1.7 \% )\). c Euhedral dolomite crystals floating almost isolated in a microcrystalline calcite matrix of a dolomitic wackestone (Malm ζ 4–5). No porosity is visible in this thin section but \(\phi_{\text{eff}}^{\text{w}}\) of sample is 2.4%. d Idiotopic dolostone (medium crystalline) with abundant intercrystal porosity (Malm ζ 4–5) reaching \(\phi_{\text{eff}}^{\text{w}}\) of 16.3%. e Hypidiotopic dolostone (medium crystalline) showing some intercrystal and vuggy porosity (arrows) of dissolved fossil fragments. Fragment of a bryozoan (Br) is still preserved in one of the vugs (\(\phi_{\text{eff}}^{\text{w}}\) = 8.6%, Malm ζ 1). f Xenotopic (non-rhombic) dolostone with sutures along contacts of coarse dolomite crystals (Malm δ). Due to complete dolomitization and compaction, pore space is highly reduced in this sample (\(\phi_{\text{eff}}^{\text{w}}\) = 1.4%)Back to article page