Improved water saturation estimation in shaly sandstone through variable cementation factor

Abstract Estimation of water saturation, S w , in shaly sandstone is an intricate process. The surface conduction clay minerals adds up to the electrolyte pore spaces, thus generating high formation conductivity that overshadows hydrocarbon effect. In each resistivity-based saturation model, key parameter factor, F which typically derived from Archie’s Law. Referring a log–log plot between factor and porosity, cementation reflects slope straight line abiding case sandstone, derivation based on Law combination with Waxman–Smits equation leads higher m* . parts reservoir, counterbalanced by conductivity. Nonetheless, used clean increases estimation. this study, variable introduced into standard correlation versus Resistivity Index, RI develop model parameters. Data retrieved two fields yielded mean arctangent absolute percentage error (MAAPE) were analysed determine difference calculated measured data within 0.01–0.15 range for method. conventional method maximum MAAPE at 0.46.