Optimization of Archie's Parameters Prediction Using Genetic Algorithm Method in a Carbonate Reservoir in Southwest of Iran

Archie’s equation is one of the most fundamental equations for water saturation calculation that includes three factors: cementation factor (m), tortuosity (a) and saturation exponent (n). These factors are called the Archie’s coefficients or parameters. Any small changes in these coefficients make significant difference in the water saturation, and hence, in the volume of the hydrocarbon. Considering the geological and petrophysical properties of the hydrocarbon reservoirs, there is no accurate and reliable method for calculating these coefficients in all conditions. Here, the genetic algorithm method was used for calculating the Archie’s coefficients in an exploration well in a carbonate hydrocarbon reservoir located in southwest of Iran. As a result, the values 2.354, 2.257 and 0.902 were obtained for the Archie’s parameters m, n and a, respectively. The genetic algorithm error was also equal to 0.1641. The overall fitting between predicted water saturation amounts versus measured ones was assessed through the correlation coefficient R equal to 62%.