Research of mining and geological conditions for geological exploration in Pre-Caucasian region
- 1 — Ph.D., Dr.Sci. First Deputy General Director JSC «SevKavNIPIgaz»
- 2 — Ph.D., Dr.Sci. Associate Director Institute of Oil and Gas of North-Caucasus Federal University
- 3 — Ph.D., Dr.Sci. professor Institute of Construction, Transport and Engineering of North-Caucasus Federal University
- 4 — Ph.D., Dr.Sci. professor Engineering Institute of North-Caucasus Federal University
- 5 — Ph.D., Dr.Sci. General Director Ltd «SevKavneftegazgeofizika – New technologies»
Abstract
Taking into consideration natural depletion of reserves of hydrocarbons in Mesozoic deposits of the majority of operated deposits of North Caucasus and for the purpose of further development of oil and gas producing industry in the region it is necessary to involve a carbonaceous complex of Jura of West Pre-Caucasus with the burial depth of more than 5300 m in the development. When drafting engineering design for a construction of exploratory wells in complex mining and geological conditions driven by anomalously high overburden pressure and temperature, use of thoroughly studied field geological information and taking into consideration the experience of boring similar wells is important. The paper provides analysis of geophysical data, the results of complex studies of reservoir porosity and permeability features of rocks picked out of core-samples of the first exploratory well on Krupskaya zone (porosity, permeability, electrical, acoustic, lithological characteristics), pressure-and-temperature conditions. The information obtained allowed to specify technological parameters of boring and tailing-in and to give recommendations regarding the way of exploratory wells boring and use of borehole equipment. In order to avoid the development of significant hydrodynamic pressure in the borehole which provokes gas showings it is necessary to keep on a certain level of minimal values of mud rheology parameters (dynamic shear stress τ = 70¸135 dPa; plastic viscosity η = 25¸35 mPa·s). For the purpose of real-time keeping of overbalance with anomalously high overburden pressure, control and regulation of calculated head pressure a stripper head should be included into the equipment configuration. Furthermore well head equipment and blowout preventer equipment must be designed for expected gradient of overburden pressure.
References
- Potapov A.G., Anan'ev A.N., Khristenko Yu.P. et al. Influence of hydrogen disulfide on drilling muds and methods of con-trol and chemical bonding of hydrogen disulfide. RI «Burenie gazovykh I morskikh neftyanykh skvazhin». Мoscow: VNIIEgazprom, 1980. Iss.4, p.28-36 (in Russian).
- Galyan D.A. Deacidification of hydrogen disulfide in drilling liquids during boreholes drilling. Мoscow: VNIIEgazprom, 1983,p.53 (Obzornaya informatsiya. Ser. «Burenie gazovykh i gazokondensatnykh skvazhin». Iss.5) (in Russian).
- Gasumov R.A. Geological factors affecting the quality of well casing (sample of a certain well of Pribrezhnaya group of deposits). Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdenii. 2014. N12, p.48-53(in Russian).
- Gasumov R.A., Il'chenko L.A. Complex scientific and technical solutions for issues of search, exploration and development of hydrocarbon reservoirs of the South of Russia. Nauka I tekhnika v gazovoi promyshlennosti. 2013. N4 (56), p.16-20 (in Russian).
- Gasumov R.A. Peculiarities of small deposits development (example of gas condensate reservoirs of North Caucasus). Zapiski Gornogo instituta. 2016. Vol.220, p.556-563 (in Russian).
- Goronovich S.N. Methods of providing compatibleness of drilling intervals. Мoscow: Ltd «Gazpromekspo», 2009, p.356 (in Russian).
- Dubenko V.E., Chernukhin V.I., Vasil'ev V.A. Designed method of justification of the intervals of liner strings installation in gas boreholes. Puti povysheniya skorostei bureniya I sokrashcheniya srokov stroitel'stva skvazhin: materialy nauchno-tekhnicheskogo soveta (Tyumen', noyabr' 2004). Мoscow: IRTsGazprom, 2005, р.102-112 (in Russian).
- Leonov E.G., Isaev V.I. Aerohydrodynamics in drilling. Мoscow: Nedra, 1987, р.304 (in Russian).
- Obukhova Z.P., Kutovaya A.A., Kiril'chenko N.E. Salt composition determination in corrosion products. Gazovayapro-myshlennost', 1982. N4, p.35-36 (in Russian).
- Protosenya A.G., Verbilo P.E. Study of compression strength of a fractured rock massif. Zapiski Gornogo instituta. 2016. Vol.223, р.51-57 (in Russian).
- Barton N. Shear strength criteria for rock, rock joints, rockfill and rock masses: Problems and some solutions // Journal of Rock Mechanics and Geotechnical Engineering. 2013. Vol. 5. N 4. P. 249-261.
- Effects of fracture geometry and stress on the strength of a fractured rock mass / A.Khani, A.Baghbanan, S.Norouzi, H.Hashemolhosseini // International Journal of Rock Mechanics & Mining Sciences. 2013. Vol. 60. P. 345-352.
- Numerical determination of strength and deformability of fractured rock mass by FEM modeling / Yang Jian Ping, Chen Wei Zhong, Yang Dian Sen, Yuan Jing Qiang // Computers and Geotechnics. 2015. Vol. 64. P. 20-31.
- Rahman S.S. Treatment of drilling fluid to combat drill pipe corrosion // Corrosion (USA). 1990. N 9. Р. 778-782.
- Use of inhibitors for scale control in brine-producing gas and oil wells / L.A.Rogers, K.Varughese, S.M.Prestwich, C.Q.Waggeot, M.H.Salmf, J.H.Oddo, E.H.Street, M.B.Tomson // SPH Prod. Eng. 1990. N 1. Vol. 5. P. 77-82.