The paper compares conventional and alternative methods of hydraulic fracturing (fracking) in wells with close water-oil contact in low-permeability reservoirs of the Tournaisian Stage featuring high risk of formation's bottom water breakthrough. Developing this type of reservoirs is not as efficient as other structures in terms of drilling, development control by means of formation pressure maintenance system and hydrodynamics of products extraction due to the peculiarities of geological structure and poroperm properties of formations. The theory part of this article presents typified data on critical specific resistivity values of carbonate deposits of oil fields in the south-eastern part of the Republic of Tatarstan used to estimate fluid saturation of rocks distributed by oil saturation ratio depending on induction values of electrometry in an open hole. The article also provides information on the geological structure of the Tournaisian Stage sediments with more extensive breakdown into Kizelovsky, Cherepetsky, Upinsky and Malevsky horizons, and briefly outlines the theory of hydraulic fracturing in the context of the peculiarities of fluid percolation during modeling of fracturing processes and their subsequent implementation, and demonstrate the main drawbacks and advantages of the technology. The paper presents a comparative analysis of hydraulic fracturing processes using conventional (guar gum) technology and an alternative technology based on hydrophobically associative polyacrylamide with distinct surfactant properties in carbonate reservoirs of the Tournaisian stage of the Rzhavetskaya structure of the Letneye oilfield in the Republic of Tatarstan. The results of the survey suggest that the alternative technology makes it possible to implement gentle fracturing by reducing the risk of fracture penetration into the water-bearing zone of the reservoir, including the peripheral areas of deposits with minor oil-saturated thickness, to bring the oil production rate to a profitable level due to the absence of colmatation (clogging) by guar within the target interlayers, to increase the number of wells eligible for hydraulic fracturing and to bring into development the reserves that were previously considered substandard.
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