Abstract：Oil-water layers in low resistivity reservoir were discovered by using an improved fuzzy comprehensive decision method that involves various characteristics, the corresponding multiparameter logging data, exploration and development data of Gaotazi low resistivity reservoir in Dalaoyefu oil field in Jilin Province. Authors give a practical method for computing both weight coefficient and membership degree, describe haw to identify oil-water layer and discuss some matters relating to its application. The processing results of logging data from 489 boreholes prove the method correct and practical.
