STUDYING THE EFFECT OF POLYMER COMPOSITIONS ON THE FILTRATION FLOWS OF THE Yu<sub>1</sub><sup>2+3</sup> FORMATION OF THE OIL FIELD "X"
The relevance of the research consists in search for methods for methods for increasing oil recovery aimed at growing the coverage of oil reservoirs developed by flooding, which will allow continuing the operation of fields with high depletion of reserves at the last stages of development. Involvement in the development of complexly localized non-drainable reserves due to the injection of polymer compositions will extend the life cycle of depleted fields and increase the final oil recovery factor. Purpose: to study the impact of injection of polymer compositions on the change in the filtration flows of an oil reservoir in order to increase the final oil recovery factor. Objects: sand layers of the Yu<sub>1</sub> horizon of the Vasyugan suite, distinguished by their heterogeneity, inconsistency in thickness, and different permeability along the section. Methods: analysis of the recovery of oil reserves in terms of displacement characteristics, as well as analytical dependencies; analysis of the current state of development; assessment of the effectiveness of the formed waterflooding system; analytical calculations using the filtration equation; laboratory studies on a filtration model; analytical evaluation of the results of testing the selected compositions at the oil field «Х». Results. The article summarizes the results of experimental studies of the effect of adding polymeric reagents to the composition of the fluid injected into the formation on changing the reservoir properties of the productive formation. The paper introduces the results of laboratory studies to determine the technologies and compositions for the implementation of the program for the injection of polymers into the Yu<sub>1</sub><sup>2+3</sup> formation of the oil field «Х». The filtration model of a real reservoir was created from core samples of the field under consideration especially for the research in laboratory conditions; the conditions for fluid filtration through the core column are as close as possible to reservoir ones. The paper introduces the results of pilot work on application of the technology of injection of polymer compositions into the Yu<sub>1</sub><sup>2+3</sup> reservoir of the oil field «Х». The authors carried out the analysis of the effectiveness of the work, made the recommendations for further use of the technology of injection of polymer compositions into the reservoir.