Gazprom Neft has used the recent St Petersburg International Gas Forum (SPIGF) to present proprietary software ensuring optimum efficiency in calculating key criteria in hydraulic fracturing (fracking)* at unconventional reservoirs (the so-called “Bazhenov” formation). The new simulator was developed in conjunction with the Moscow Institute of Physics and Technology, and is currently the only IT product in the world developed specifically for the Bazhenov strata.
The programme developed helps assess how a crack or fissure will develop within the strata, and allows its form (length, thickness, width and other geometric characteristics) to be simulated, as well as allowing an assessment to be made of the amount of oil likely to be produced through such borehole. Highly complex mathematical and physical models are used to assess the impact of dozens of variables.
The Gazprom Neft Joint Scientific and Research Centre, together with leading Russian research institutes, is involved in developing technologies for the development of unconventional reserves. Work is being undertaken as part of a federal programme for extensive research into the Bazhenov formation.
The “Bazhenov formation” refers to a specific geological stratum identified in the centre of Western Siberia, running to depths of
Hydraulic fracturing is one of the most effective means of stimulating production, particularly in unconventional and hard-to-recover reserves, including shale oil, as is the case at the Bazhenov formation. Hydraulic fracturing, moreover — a technologically complex and rather expensive operation — requires intensive preparatory works. The outcomes of such modelling allow optimum criteria for fracking to be selected.
Alexey Vashkevich, Head of the Directorate for Geological Exploration and Resource-base development, Gazprom Neft, commented: “Our main job is to devise strategies for developing the Bazhenov formation that are as user-friendly as those used in traditional reserves. The Bazhenov formation differs from traditional strata in being practically impenetrable. The main purpose of the technologies we have developed is to create artificial conductive-fissure systems. The simulator we have developed allows us, in fact, to work out how to maximise coverage of strata through a fracture network and secure a viable oil inflow.”
* Hydraulic fracking is a means of increasing oil production at a field. It involves the high-pressure injection of a mixture of fluids and a special proppant agent (proppant) into strata. The process of injecting the mixture creates highly conductive channels (“hydraulic fractures”) connecting the well (bore hole) and the strata. These fractures allow oil to flow that would not, under other circumstances, reach the well. Under multi-stage fracking, multiple fracking operations can be undertaken from a single horizontal well, allowing a manifold increase in the catchment area covered from that well.
** The consortium investigating the Bazhenvov formation includes the Engineering Centre of the Moscow Institute of Physics and Technology, the Geology Faculty of Moscow State University, the Gubkin Russian State Oil and Gas University, and the Skolkovo Institute of Science and Technology (Skoltech). The Gazprom Neft Joint Scientific and Research Centre is acting as industrial partner in this project, as well as participating in the co-financing of the research programme.