During the Bazhenov shale development, a new integrated approach to planning the multistage hydraulic fracturing was developed. This approach is applied to each drilled well,thus implementing the strategy of technological experiment, where the well serves as a separate testing ground for testing the developed methods and implementing new technologies.With the help of modern multistage hydraulic fracturing modeling tools, developed jointly with technological partners for the project tasks, a technological experiment plan is drawn up for the well and contains new,potentially effective solutions, as well as the already accumulated experience. In accordance with the developed plan,the multistage hydraulic fracturing operation is modeled, taking into account the geological and geomechanical features of the object, such as lateral and zonal heterogeneity and the existing natural fracture zones.
Using the developed approach, multistage hydraulic fracturing operations were performed on more than 25 wells drilled at the Bazhenov shale, which is equivalent to 450 well operations.During this time, various technological solutions have been developed, tested and implemented,which include the use of new hydraulic fracturing fluid samples, the selection of optimal well perforating scheme,the use of combined proppant packs and hydraulic fracturing using mainly low-viscosity fluids.Active use of specialized software for modeling the hydraulic fracturing process and close cooperation of software developers with hydraulic fracturing engineers has led to the expansion of the functionality of the developed software product, improving its quality, convenience and stability of operation. According to the initial assessment,the implementation of the technological experiment strategy in conjunction with the use of specialized software led to a reduction in drilling hazard mitigation during multistage hydraulic fracturing operations,as well as to an increase in accumulated oil production by an average of 37 %.A database of knowledge and individual,successful technological solutions available for use in similar projects has been created.
Due to the Bazhenov shale unique structure and properties,it was necessary to adapt existing solutions in the industry for conducting multistage hydraulic fracturing in ultra-low layer permeability.The process of searching and creating new technologies, tools for modeling the multistage hydraulic fracturing process and analyzing the results was also successfully initiated. The developed approaches have already shown their effectiveness, and the work results can be replicated on subsequent wells, as well as on similar objects.
