On uncertainty level reduction in managing waterflooding of the deposits with hard to extract reserves

Abstract

Relevance. In the context of the decline in growth of explored oil reserves, the Russian oil industry faces an important task of involving the deposits with hard-to-recover reserves characterized by a low recovery level but with significant residual reserves in active development. The West Siberian oil and gas province Terrigenous reservoirs of Cretaceous deposits refer to such objects. Increase of efficiency of their development will significantly expand the country resource base. The aim of the research is to develop the complex of algorithms and techniques that reduce the uncertainty and risks in making manage-ment decisions aimed at improving the efficiency of asset management by subsoil users. Methods. The authors have carried out the geological and commercial analysis and the experience generalization of contour waterflooding using in the conditions of various groups of relatively homogeneous objects applying a set of available information on waterflooding with the wide various mathematical algorithms for data processing and information criteria application. Results. The paper introduces the algorithms which allow estimating producing and injection wells interaction degree at sites with different parameters values characterizing the geological structure in different locations, choosing producing wells for transferring them for injection ones, determining the need to drill new wells and sidetracks, using the transit fund wells, estimating the expected production rate of producing wells surrounding the injection ones, as well as solving a number of other tasks of reserves development. It was found out that under the different groups of objects conditions, the degree of influence of geological parameters on the degree of interaction between the wells is different, that causes the differentiated approach not only to the choice of distances between production and injection wells to increase the injection efficiency but also for other tasks of oil production facilities managing. Conclusions. The generalization conducted, the results and the algorithms obtained complement the scientific and methodological foun-dations for increasing the efficiency of hard-to-recover oil deposits development managing by injecting water into the reservoir within the West Siberian oil and gas province with minimal uncertainties and risks.