Saturation exponent determination by using genetic algorithm in carbonate reservoirs: A case study in Sarvak Formation

Abstract

Well logging analysis has been recognized as the best way to characterize reservoir properties, especially water saturation. Archie equation is known as the best method to estimate water saturation from well logging data. Determination of Archie parameters is an incessant challenge in advanced reservoir engineering because of its complex intrinsic. Measurement of Archie parameters in core laboratory has a high sensitive, expensive and time consuming procedure, that causes the excluding of core analysis to be impossible for the entire depth of reservoir zone. Although some empirical and mathematical models have been introduced to measure cementation factor, without the need of coring, there is not exist a reliable method to estimate saturation exponent in similar way.Genetic algorithm is excelled than other meta-heuristic global search methods, which could be used in solving engineering problems. In this study, a genetic algorithm based strategy has been developed to develop a model to estimate saturation exponent from a core of drilled well in Sarvak Formation at Marun Oil Field in Iran. This model has been validated with laboratory measurements of saturation exponent with the accuracy (R2) of 0.91 and the miscalculation (MSE) of 0.23.