The authors identified the evolution stages of development system for the central section of the Priobskoye field (southern part) and evaluated the effectiveness of the implemented solutions. The object of study is the low-permeable horizons AC10 and AC12, identified at the beginning as a single development object. Joint exploitation of different-permeable formations AС10 (6.9·10-3 mkm2) and AС12 (2·10-3 mkm2) led to a twofold lag in the production of oil reserves from the worst formation. The authors explored key issues in the development of low-permeability reservoirs: if it is it possible to obtain relatively high rates of oil recovery under the indicated conditions and by what means can they be ensured; what will be the characteristic of the water-flooding of the area developed with the massive and repeated use of large-volume hydraulic fracturing; are there any prospects to ensure oil recovery at such facilities - more than 0.3. The study of the 20-year history of the development of the central section of the AC10-12 reservoir allowed to answer positively the above questions. The factors for a rapid increase in oil production in the area at stages I-II are high drilling rates, repeated large-volume hydraulic fracturing in wells, creation of low bottomhole pressures (less than 5 MPa) in production wells and high wellhead injection pressures (more than 20 MPa) , correct consideration of the probable direction of development of hydraulic fractures in the reservoirs. The factors for maintaining oil production at the III stage of the development of the site were quick commissioning of infill production wells; mass drilling of horizontal wells with multi-stage hydraulic fracturing into separate layers in order to locally subdivide the AС10-12 object; selective sidetracking from idle wells; reduction of bottomhole pressure in high-watered wells − up to 3 MPa; regulation of water injection volumes by area zones, reduction of the current withdrawal compensation by injection. Due to these effective measures, it was possible to ensure a favorable characteristic of oil displacement by water. As a result, the final recovery factor expected for the area will be 20% higher than the oil recovery approved in general for the AC10-12 facility in the southern part of the Priobskoye field.
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