Over the past few years, hard-to-recover reserves have been actively developed. The main method of well stimulation in case of low reservoir permeability is hydraulic fracturing. Currently, commonly used water-based fracturing fluids are cross-linked guar gels. The advantages of these systems include high values of effective viscosity, due to which the compositions retain the proppant well in volume. Another advantage is controlled time of cross-linking and destruction, which can be varied over a wide range by changing the concentrations of the reagents in the compositions. However, such fluids have several disadvantages; the main one is the clogging of the pore space of the fractured zone and the proppant pack by the remains of the undestroyed polymer. Clogging and, as a result, a decrease in the fracturing efficiency can also be related to swelling and subsequent migration of particles of clay minerals. New types of fracturing fluids that can minimize the disadvantages of cross-linked guar systems remain underestimated because of established approaches to testing sand-bearing fluids. Such liquids are compositions based on viscoelastic surfactants and synthetic polymers. The authors propose integrated approach to the study of structural and mechanical properties based on a combination of rotational and oscillatory rheology, and a comparative analysis of the influence of fluids on the reservoir rock.
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