3-D pore-scale modelling of heterogeneous sandstone reservoir rocks and quantitative analysis of the architecture, geometry and spatial continuity of the pore network

A new method for generating realistic homogenous and heterogeneous 3-D pore-scale sandstone models is presented. The mcthod is based on numerical modelling of the main sandstone-forming geological processes - sandgrain sedimentation. compaction. and diagenesis. Petrographical analyses provide the necessary input for the modelling. The architecture and geometry of the generated pore space networks are determined using 3-D image analysis techniques. A scale-independent invasion percolation based analysis determines the spatial continuity of the pore network in the X. Y. and Z directions. The resulting spatial continuity function, which is an ellipsoid. is used as a heterogeneity descriptor for the pore network. A 3-D pore network which is representative of a strongly water wet Bentheimer sandstone is generated and used as input to a two-phase network flow simulator. Computed absolute and relative permeabilities arc in good agreement with thosc determined experimentally.