The injection assays involved the following steps: (1) in order to determine the absolute permeability and the porosity of the plug, brine (2% KCl solution) was injected at a constant flow rate of 0.2 mL/min, through the plug; (2) once the plug was saturated with brine, oil with a viscosity of 9 cP was injected at a constant flow rate of 0.2 mL/min; (3) with the purpose of determining the mobility ratio (Eq. (2)), the volume of displaceable oil (Eq. (3)), the volume of displaced oil (Eq. (4)) and the displacement efficiency (Eq. (7)) in the conventional method, brine was injected again, after plug saturation, at a constant flow rate of 0.2 mL/min. The volumes of oil and water were measured in graduated tubes; and (4) similar to the 3rd step, microemulsion with a 32 cP viscosity was injected at a constant flow rate of 0.2 mL/min with the objective of calculating the parameters for an equivalent EOR method, namely the mobility ratio (Eq. (2)), the volume of displaceable oil (Eq. (3)), the volume of displaced water (Eq. (5)), the volume of displaced oil (Eq. (6)) and the displacement efficiency (Eq. (7)). The collected samples initially contained water and oil. The volumes of oil and water were also measured in graduated tubes, and the samples were collected at previously defined time intervals. After some time, oil started to be produced mixed with the microemulsion, and from this point this amount of oil was not determined. Finally, totally clear microemulsion samples were collected, with no oil residues.