Mechanism of self-induced haudralic fracturing in undeveloped formations and assessment of its impact on field development on the example of the Priobskoye field

Background. Reservoir flooding is one of the main methods of oil production in low-permeability fields. At the same time, the natural decrease in the effectiveness of the flooding method leads to an increase in the water injection pressure. One of the side effects is the so-called self-induced crack growth in injection wells, which can be accompanied by a crack breakthrough in the production well operation area. A crack breakthrough, in turn, leads to problems associated with unproductive injection.Aim. To establish the relationship between the development of self-induced hydraulic cracks of technogenic origin with the technological operation parameters of injection wells, the geological properties of formations, the tectonogenetic features of stress distribution across the lower part of the sedimentary cover of the research site (the Priobskoye field).Materials and methods. Hydraulic fracturing design calculation programs: Planar 3D, FracCADE. Analytical tools: Hall plot.Results. The relationship between abnormally high reservoir pressures with the phenomenon of technogenic self-induced hydraulic fracturing is determined based on the obtained complications in drilling boreholes, associated with the production of abnormally high reservoir pressures in transit and undeveloped formations. The formation mechanism of self-induced hydraulic fracturing is established. The feasibility of optimizing the current development system in terms of achieving the design oil recovery coefficient of the reservoir is considered.Conclusion. Optimization of the existing development system at the pilot site of the Priobskoye field using low-permeable reservoirs is proposed. In the case of its successful application, the approach can be used for the entire field, as well as other fields similar in geological structure.

abnormally high reservoir pressure, hydraulic fracturing, low permeability, regional stress, unproductive injection