The current publication represents the fundamentally new approach to selection of well candidates for refracturing that is suggested based on the stress-deformed reservoir state monitoring using the geomechanical modelling tools and downhole investigations. On the example of RN-Uganskneftegas LLC the statistical analysis of well-candidates base for refracturing is implemented. The necessity for developing of innovational methods for the increase of well stimulation works is demonstrated. As a result the method of well-candidates search for refracturing is suggested where the effect of spatial fracture reorientation will take place. The analysis of a reservoir stress-deformed state alteration is implemented on the different scales through the study of experimental researches applied on a core sample and dynamic characteristics of a reservoir. The post-event analysis of wells with refracturing is implemented where the fracture reorientation was diagnosed by the result of cross-dipole acoustic log surveys and mathematical modeling. Based on the post-event analysis and previously made scientific investigations related to rock mechanics study of a low permeable reservoirs the criterion of secondary fracture reorientation are derived. In order to understand the lower limit of commercial viability for implementing refracturing with fracture reorientation in comparison with refracturing without fracture reorientation the multivariate reservoir simulation is applied. The new approach of refracturing is demonstrated for wells with high risk of fracture’s breakthrough to the water injected front. Solution and risks analysis in such a case is demonstrated. The presented innovational approach allows to increase the quantity of well-candidates for refracturing, to increase the recovery factor of the oilfield, and to minimize the risks while implementing such well stimulation works.
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