Features оf Hydraulic Fracturing in Sediments with Hard to Recover Reserves

Introduction. When developing productive deposits containing hard-to-recover oil reserves, the main difficulty is associated with low values of the reservoir properties of the reservoirs and their significant heterogeneity. The use of hydraulic fracturing technology allows solving these problems by increasing the well drainage area, and also as a means of intensifying production.

Materials and methods of research. The study of the process of hydraulic fracture development in the deposits of the Bazhenov formation in a vertical well showed that when water is injected, long narrow fractures are formed in the formation, their filling with subsequent supply of a fracturing fluid with proppant leads to an increase in the width and height of the created fracture. Due to the hydrophobic properties and increased brittleness of the rocks of the Bazhenov formation, an effect similar to hydraulic fracturing is also possible during the injection of water into the formation at high pressures, for example, when organizing a waterflooding system. Another direction is multi-zone hydraulic fracturing. The advantage of this method is the greater distribution of fractures over the area compared to point hydraulic fracturing operations.

Results and Discussion. On the deposits of the Bazhenov formation, pilot work was carried out to create artificial fracturing by pumping water. The positive effect was expressed in a twofold increase in oil recovery in the pilot area. As a negative side effect, a sharp increase in water cut was noted. The experience of using multi-zone hydraulic fracturing in the conditions of the Bazhenov formation was considered on the example of the deposits of the Surgut arch. The dynamics of flow rates and cumulative oil production by wells during operation is presented. Also, a comparison was made of the main performance indicators of wells with multi-stage hydraulic fracturing with the average indicators of directional wells of the same fields.

Conclusion. The pilot work conducted on water injection into the Bazhenov formation deposits unambiguously showed that additional fracturing is formed in the reservoir and the volume of additional fractured capacity is directly proportional to the volume of injected water. The experience of using multi-zone hydraulic fracturing revealed the advantages of this technology compared to directional wells. Under conditions of reservoir reservoir properties uncertainty, the creation of artificial conductivity using hydraulic fracturing may be the only way to ensure well productivity. MSHF in horizontal wells forms a system of fractures in a large volume and seems to be more effective in such conditions compared to conventional hydraulic fracturing.

1. Andreev V.E. Andreev V. E., Batalov D. A., Dubinsky G. S., Mukhametshin V. V. Prospects for the use of hydraulic fracturing to intensify the recovery of oil reserves and increase oil recovery // Energy Efficiency. Problems and Solutions: XV International Scientific and Practical Conference, Ufa, October 27, 2015. Ufa: Institute for Problems of Transportation of Energy Resources of the Republic of Bashkortostan, 2015. P.109–110. (In Russ.).

2. Afanasiev I.S. et al. Bazhenov formation. General review, unresolved problems // Russian oil and gas technologies. 2011. No. 25. P. 24–35. (In Russ.).

3. Verikosin A.E., Zinovieva L.M. Features of the technology of flushing and development of horizontal wells after selective hydraulic fracturing in the fields of Western Siberia // Nauka. Innovation. Technology. 2015. No. 3. Р. 79–90. (In Russ.).

4. Grachev S.I., Kopytov A.G., Korovin K.V. Estimation of the increase in drained oil reserves by wells during hydraulic fracturing, Izv. Oil and gas. 2005. No. 2. Р. 41–46. (In Russ.).

5. vanov A.S., Sarancha A.V. Brief analysis of the effectiveness of geological and technical measures carried out at the fields of the Khanty-Mansi Autonomous Okrug-Yugra // Academic Journal of Western Siberia. 2019. Vol. 15. No. 1. P. 11. (In Russ.).

6. Karpov V.B. New ways of developing hydrocarbon reserves in the deposits of the Bazhenov formation // Proceedings of the VIII International Technological Symposium. Moscow. 2013. Р. 47. (In Russ.).

7. Klubova T.T., Khalimov E.M. Oil-bearing capacity of the deposits of the Bazhenovskaya suite of the Salym field. M.: VNIIOENG, 1995. 40 p. (In Russ.).

8. Kulakov K.V., Tishkevich S.V., Ostashuk A.D., Barkalov S.Yu. «Gazprom Neft» is a leader in terms of competencies in conducting repeated multi-stage hydraulic fracturing // PROneft. Professionally about oil. 2019. No. 2. Р. 42–47. DOI: 10.24887/2587-7399-2019-2-42-47 (In Russ.).

9. Marakov D.A., Krasnova E.I., Inyakin V.V. et al. Experience in the development of oil and gas fields using hydraulic fracturing // Academic Journal of Western Siberia. 2014. Vol. 10. No. 5. Р. 117–119. (In Russ.).

10. Panyak S.G., Askerov A.A., Yusifov T.Yu. Hydraulic fracturing is an effective method for additional extraction of oil and gas reserves // Izvestiya vysshikh uchebnykh obrazovaniya, Izv. Oil and gas. 2011. No. 5. Р. 56–59. (In Russ.).

11. Repnik A.A., Bochkarev V.A. Influence of fragility and plasticity of shale formations on the efficiency of hydraulic fracturing // Neftepromyslovoye delo. 2016. No. 6. Р. 26–35. (In Russ.).

12. Sarancha A.V., Garina V.V., Mitrofanov D.A., Levitina E.E. Results of pilot development of the Bazhenov formation at the West Sakhalin deposit // Fundamental Research. 2015. No. 2–14. Р. 3052–3055. (In Russ.).

13. Sarancha A.V., Mitrofanov D.A., Sarancha I.S., Ovezova S.M. Development of the Bazhenov Formation at the Ai-Pimskoye field // Modern problems of science and education. 2015. No. 1–1. Р. 204. (In Russ.).

14. Sonich V.P. et al. Problems and prospects for the development of the Bazhenov formation // Oil industry. 2001. No. 9. P. 36–68. (In Russ.).

15. Chertenkov M.V., Kovalchuk S.P., Zolova I.V. et al. Field development planning and management: new approaches, modern solutions. 2013. No. 9. Р. 82–85. (In Russ.).

16. Yarkeeva N.R., Khaziev A.M. Application of hydraulic fracturing for the stimulation of oil flow in wells. 2018. Vol. 16. No. 5. P. 30–36. DOI: 10.17122/ngdelo-2018-5-30-36 (In Russ.).

17. Boschee P. Produced and Flowback Water Recycling and Reuse. Economics, Limitations, and Technology // Oil and Gas Facilities. 2014. February. Р. 16–21.

18. Sarancha, A.V., Mikhaylov S.Y., Inyakin V.V. Shale oil in Bazhenov formation on deposits of Western Siberia // IOP Conference Series: Earth and Environmental Science, SaintPetersburg, March 23–24, 2017. Saint-Petersburg: Institute of Physics Publishing, 2017. P. 042019. DOI: 10.1088/1755-1315/87/4/042019

19. Schramm E. What is flowback, and how does it differ from produced water? //Institute for Energy and Environmental Research of Northeastern Pennsylvania Clearinghouse website [Electronic resource]. URL: http://energy.wilkes.edu/205.asp. (Accessed 18.04.2019).

20. Paklinov N.M., Shepelevich A.N., Strekalov A.V. Creation of the installation for studying the impact of current pulse excitation on the bottomhole formation zone // IOP Conference Series: Earth and Environmental Science: conference 1, Tyumen, 28–29 September 2018. Vol. 181. Tyumen: Institute of Physics Publishing, 2018. P. 012024. DOI: 10.1088/1755-1315/181/1/012024