Research On Preferential Seepage Channels Identification Methods Based On Static And Dynamic Data

Most reservoirs of China belong to the continental deposition. After long-term water flooding, more and more preferential seepage channels(PSC) have appeared, which would influence the coverage of water flooding and raise of recovery. The paper combined static and dynamic data with several different methods to recognize the PSC, and integrated these methods to a comprehensive approach.The alternation of the static data of layer can reflect the effect which the development of PSC generates to the reservoir. Paying attention to the alternation and quantifying it, the reservoir parameters could be used to make judgment about the PSC. Based on the analytical hierarchy process, the paper proposed a comprehensive layer factor in the light of results of tracer test, and recognized the target reservoir with this method.In the well group, a suit of dynamic alternation exists in the whole development process, which reflects in the change of liquid production and water content and some other parameters. Based on the Fuzzy theory, the paper united dynamic data with static data to build up an evaluative model, and utilized the discriminant factor to recognize the PSC in the reservoir. To avoid the subjective problem in the common fuzzy methods, the paper adopted the coefficient of variation method to calculate the objective weight.Apply the Hall plot method to recognize the PSC, and improve the approach to make the required data more convenient, which enhances the applicability of this method.Apparently, the dynamic association between injection well and production well reflects the change of the input rate and output rate. It is the result of pressure change actually. The paper adopted the signal analysis theory and used gray correlative method, modified gray correlative method and slop correlative method to calculate the degree of association between injection well and production well. And the paper proposed data smoothing and time delay to optimize the initial data.Through using different methods, combining static data with dynamic data, the paper utilized different directions such as water injection curve, interlayer difference and water injection profile and others to research. Take DH1-7-8 well group as an example, recognized the PSC comprehensively and identified the distribution location.