Deposits of Eastern Siberia characterized by a complex geological structure as well as cavity-fractured reservoir in Riphean dolomite deposits. The uniqueness is caused by high anisotropy of permeability, absence of permeability of rock matrix, ultra-low porosity of formation (1-2%), abundance of tectonic disturbances, subvertical fracturing. These special aspects create significant difficulties in assessment of residual reserves and saturation nature when selecting wells-candidates for wellwork operations. The absence of reliable methods for forecasting distribution of poroperm properties in interwell space and impossibility of the definition of the carbonate reservoir saturation with porosity less than 2% lead to the high risks of unprofitability of the activities. The article summarizes the accumulated experience of geological and technological measures implementation at the wells of the Kuyumbinskoye oil-gas-condensate field. The main method of improved oil recovery for carbonate reservoir is treatment by compositions on the basis of hydrochloric acid, including the use of diverters due to the specific distribution of permeability. Besides acid treatment methods, additional reservoir perforation is used as a tool to increase the coverage. New for this reservoir is the method of limiting water inflow by lowering liners with sleeves to enable bridging of water / gas breakthrough intervals during operation. In 2022, work began on testing multistage hydraulic fracturing technology. The uniqueness of such works lies in the properties of the rock matrix - it is impermeable and has almost zero porosity (0.5-0.7%). Under such conditions, multistage hydraulic fracturing has not been performed in the Russian Federation. Pilot work is scheduled to be completed in 2023. The tested and potentially effective technologies mentioned in the article have been reworked and adapted to the geological conditions of the field.
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