This work investigates the effect of wellbore storage on the analysis of pressure buildup data obtained in a solution-gas-drive reservoir. All results assume radial flow to a single well draining a solution-gas-drive reservoir with the initial reservoir pressure equal to the initial bubble-point pressure. Although connate water is present, the water is immobile and therefore during production only oil and gas flow within the reservoir. Wellbore storage effects are incorporated by specifying a sandface oil flow rate which during shut-in decreases exponentially from a stabilized constant value of the surface oil flow rate at the time of shut-in to zero. Based on a superposition equation new computational equations for computing effective oil and gas permeabilities as pointwise functions of pressure from the measured values of the shut-in wellbore pressure are presented. The computational equations require that the sandface oil flow rate be measured and incorporated into the analysis. By combining the computed effective permeability versus pressure relation with the oil saturation versus pressure results computed from the material balance equation, one can approximately construct the effective oil and gas permeabilities as functions of oil saturation. It is also shown that a semilog plot of shut-in pressure-squared versus Horner time represents a viable method for obtaining estimates of the mechanical skin factor and the effective oil permeability at the final value of shut-in wellbore pressure.

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