Flooded Layer Logging Data Interpretation

Water injection development has been widely used in most of oilfields in our country, and the majority of them have entered high or extra high water development stage. The serious water increasing makes the oil exploration more and more difficult in late production. Therefore, in view of this phenomenon, it is necessary to accurately predict the remaining oil distribution and efficiently exploit them.After water flooding, the lithology, physical property and the electrical parameter of oil layer will change a lot. In view of this phenomenon, with the centre of log interpretation, aimed at evaluating the water flooded layer and determining the saturation of remaining oil, this paper analyzes the change of porosity, permeability, formation water salinity as well as rock wettability of the water flooded layer, and researches the variation characteristics of formation resistivity with different types of waterflooding through the rock electricity experiments. According to the variation characteristics of oil layer after water flooding, a series of methods to evaluate water flooded layer qualitatively are summed up with the help of conventional logging curves. In addition, a set of log interpretation model is established based on reservoir parameters. After discussion of the adaptability of Archie equation comprehensively, new types interpretation model of water flooded layer are set up based on Archie formula. And the resistivity of mixed fluid after water flooding is calculated using self-potential logging curve. Thereby, the waterflooding level and saturation of the remaining oil can be determined.Taking XEM oilfield as the research object, this paper makes calculation of the remaining oil saturation by the log interpretation methods for water flooded layer that it adopt. The results of the application at the scene shows that the method proposed in this paper is correct, reliable, high moisture content of the oil remaining oil saturation distribution forecasts, further pattern adjustment, the infill well, the relationship between injection and production adjustment, which are important guiding significance, with the promotion of good value. It will play an important role in the distribution analysis of remaining oil saturation, further pattern modification, location of infill wells, and adjustment of injection-production relation, profile control and exclusion of water. This method has better popularization and application value.