One of the urgent tasks of field development is to ensure the optimal process of reservoir flooding in order to achieve the maximum oil recovery factor. Modern systems of reservoir pressure maintenance work with injection modes in which man-made cracks (auto-fracturing) form and spread. This is one of the key complicating factors in the development of low-permeability reservoirs. To date, there is uncertainty in assessing the parameters of auto-fracturing cracks depending on the injection modes. Uncontrolled growth of man-made cracks can lead to premature flooding of producing wells or the formation of stagnant zones.
The article discusses the mechanism of formation and propagation of auto-fracturing cracks during water injection by the reservoir pressure maintenance system. The working conditions of a technogenic crack in the mode of ensuring the optimal flooding process are analyzed. In conditions of high heterogeneity of the reservoir, difficulties arise in maintaining the optimal fracture geometry of the hydraulic fracturing system for a long period of development. To solve this issue, a method has been developed to maintain optimal crack operating conditions during injection by cyclically creating an auto-fracturing crack of optimal length. The application of the described approaches has received positive field results in a number of fields. The project has a wide potential for further development.
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