The reservoir heterogeneity in terms of permeability and availability of high-water-cut wells in the Botuobinsky horizon within the Eastern Siberia fields determines the need for introducing conformance control by creating seals and barriers to the injected water in the flushed zones of the formation. The Eastern Siberia reservoirs are generally characterized by low reservoir temperatures and high salinities of formation water. The paper describes the results of laboratory studies of cross-linked polymer systems in low-temperature formations (12 C) with high salininy of formation water (up to 400 g/l). It also presents the technologies based on high-molecular polymers of partially hydrolyzed acrylamide with chromium-salts-based crosslinking agents. Laboratory tests and simulations have confirmed the performance of polymer-based conformance control technologies for the Bt reservoir of Srednebotuobinskoye field. The polyacrylamide (PAA) brands available on the domestic market dissolve in 140 g/l formation water, and, as part of solutions with chromium acetate, form strong structured gels at low reservoir temperatures. At reservoir temperatures of 10-12 C, the gelling time increases up to 3-4 days. The rheological parameters of cross-linked gels at low temperatures are comparable to the strength of gels which are structured at elevated temperatures. Structured PAA gels under the influence of high-salinity water are not subject to destructive changes at low reservoir temperatures. The highly permeable cores of the Botuobinsky horizon were used in physical modeling units and allowed to demonstarte the ability to create high water flow resistances using cross-linked polymer systems. The results of rheological tests and flow experiments allow to recommend cross-linked polymers for injection into the Botuobinsky horizon rocks. A pilot program has been developed, candidate wells have been selected for technology testing, the volume of polymer slug and the well shut-in period required for structuring have been determined, and incremental oil production has been estimated.
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