Log Analysis Techniques for Quantifying the Permeability of Submillidarcy Sandstone Reservoirs

Summary A gradational diagenetic change from the "tubular" primary pore network of conventional sandstones to a pore geometry consisting of secondary-solution pores interconnected by narrow "slot-like" flow paths in low-permeability sandstones has necessitated the formulation of revised log-derived permeability equations. The equations are derived from Lower Mesaverde group core data and are tested for limitations by extrapolation to a. shallower Mesaverde interval and to a remote Travis Peak (Hosston) interval. An alternative method involving invasion inferences from a log-derived filtration index is used to complement the permeability analysis.