Predicting the Permeability of Very Low Porosity Sandstones

The permeability predictions of two geometric pore-scale models, one being predominantly granular and the other consolidated with tube-like pores, are compared with experimental results for Fontainebleau sandstones and the results interpreted. Percolation thresholds are determined from experimental data and applied in the modelling exercise by means of cut-off asymptotes on porosity. It is found that, although both granular and foamlike models yield plausible results, the granular model appears to be superior, at least for the sets of data considered. The Klinkenberg correction is analytically derived and incorporated into the models to relate gas and liquid permeabilities and an analytical expression for the Klinkenberg factor is proposed for each model. The permeability predictions are promising and yield an effective manner to correlate sandstone percolation data.