Pokuttia deep fault and its influence on tectonics and the oil- and gas-bearing of the south-eastern segment of the Carpathians

Received: September 12, 2018
Institute of Geology and Geochemistry of Combustible Minerals of NAS of Ukraine

Objective. The objective of this study is to analyze the influence of the Pokuttia deep fault on tectonics and the oil- and gas-bearing of the south-eastern part of the Ukrainian Carpathians.  Methodology. It is contained in the detailed complex analysis of the geological-geophysical data on the given area. Results. The influence in the Pokuttia deep fault on the flysch structure has revealed itself in the Boryslav-Pokuttia nappe as a series of dislocations with a break of continuity of the north-eastern orientation at the boundary between the Hutsulkyi and Boikivskyi segments with the structures horizontally displaced 10 km off and up to 1,5 km vertically- left-strike slip fault. In the Skyba nappe this is truncation of its front part of the Hutsulskyi segment. In the Dukla-Chornohora nappe and the Bitlya-Svydovets sub-nappe these are sigmoid curvature of their parts in the fault zone with amplitudes of horizontal displacements of up to 10 km. As a result, the Krasnoshora and Hoverla units are joined into single sub-nappe, and the thrust-folds of the Bitlya-Svydovets sub-nappe to a considerable extent are overlapped by it and by the Skupiv sub-nappe. Owing to post-overthrusting vertical movements the Hutsulskyi segment was uplifted during Pliocene-Pleistocene. The rise of the area with the Duklya –Chornohora nappe was the most intensive. The structures of the Bitlya-Svydovets sub-nappe are fragmentally outcropped from under it. In the territory of Romania structurally correspond to them from the north - the thrust-sheet with olistostrome Slon in the Lower Verkhovyna deposits of Oligocene, and from the south - tectonic units Toroklezh and Makla. The Pokuttia fault displaces the Precarpathian regional minimum (amplitude of about 10 km), and the Uzhok deep fault with the signs of right-shift. This is a perceptible impact of the Pokuttia fault on the sub meridional Radekhiv-Viktoriv fault. Sites of intersections of the mentioned faults, so-called knots, if the traps are available, are known to be favourable zones for hydrocarbon accumulation on commercial scales. In the light of new data  on the geological structure of the region the perspective estimate is raised for the structures distinguished of Vorohta-Yasynia (Lazeshchynska, Yasynska and Voronenkivska), as well as Semakivska and Hryniavska, where commercial influxes of hydrocarbons were obtained. This observation also concerns the structures of the basement of the Lopushna subzone of the outer zone of the Carpathean Foredeep under the overthrust of the Carpathians. Scientific novelty. For the first time, using new geological data it was possible to prove the influence of the Pokuttia fault in the zone of its action in a form of the left-strike-slip on the structures of the flysch cover. The structural parallelization of the Bitlya-Svydovets sub-nappe of the Krosno nappe of the Ukrainian Carpathians was carried out with the tectonic units of the Romanian Eastern Carpathians. Interaction of the given fault with the Precarpathian regional minimum and the Uzhok deep fault has a character of the right shift. Areas connected with these dislocations are prospective for hydrocarbon accumulations of commercial value. Practical Value. As a result of investigations essential corrections have been inserted concerning the geological structure of the south-eastern part of the Ukrainian Carpathians. Together with geochemical indications this presents new possibilities in searching for hydrocarbon deposits here.

  1. Bejer, M. A. (1969). About shift dislocations in the Soviet Carpathians. In the book: Scientific reporting conference of the geological department. (Abstracts). Moscow State University Publishing House.
  2. Bejer, M. A., Byzova S. L., Lomize M. G. Tectonic nappe of Mount Petros (Eastern Carpathians). Geotectonics, 4, 84–91.
  3. Bucur, J. (1971). Observatii privind nomenclatura tectonică in flischul cretacic si paleogen din Carpatii Orientali / Dări seamă sedint. Inst. geol.– vol.57. №5, 23–32.
  4. Cheban, V. D., Babyuk, S. G., Stepanyuk, V. P., Monchak, L. S., Anikeyev, S. G., Zhuchenko, G. O. Geological nature of the Carpathian region minimum of the gravity force. Scientific Visn. of IFNTUNG, 3(4), 183–189.
  5. Dabagjan, N. V., Kul'chickij, Ja. O., Kuzovenko, V. V., & Shlapinskyi. V. E. (1987). Basic sections of the boundary layers of the upper part of  Eocene – lower part of  Oligocene of the southern part of the Skyba, Krosno and Chernogora zones. Paleont. sb.,  24, 27–33.
  6. Dolenko, G. N. (1962). Geology of oil and gas of the Carpathians. Kyiv: Publishing House of the Academy of Sciences of the Ukrainian SSR.
  7. Dolenko, G. N., Bojchevskaja, L. T., Kilyn,  I. V., Ulizlo, B. M., & Pasternak, S. I. (Ed.). (1976). Fault tectonics of the Carpathian Foredeep and Transcarpathian Depression and its influence on the distribution of oil and gas deposits. Kyiv: Naukova dumka.
  8. Gabinet, M. P., Kulchytsky, Y. O., & Matkovsky, O. I. (1976). Geology and Mineral Resources of the Ukrainian Carpathians. Part I. Lviv: Vishcha Shkola.
  9. Glushko V. V., Lozynjak, P. Ju., & Petrashkevich, M. I. (1982). New ideas about the structure and zoning of the Carpathian Foredeep. Geology and geochemistry of combustible minerals, 58, 19–31.
  10. Glushko, V. V., & Kruglov, S. S. (1977). Justification of the directions of oil and gas exploration in the deep horizons of the Ukrainian Carpathians. Kyiv: Naukova. Dumka.
  11. Glushko, V. V., Kuzovenko, V. V., & Shlapinskyi. V. E. (1994). Scheme of tectonics of the Teresva-Chorny Cheremosh doub. . Geology and geochemistry of combustible minerals, 1–2. 158–163.
  12. Glushko, V. V., Kuzovenko, V. V., & Shlapinskyi. V. E. (2007). Geological map of the Ukrainian Carpathians. Transcarpathian, Ivano-Frankivsk, Lviv and Chernivtsi Regions of the Ukraine, 1:100000, by Report of JSC Nadra Concern. Ed. Yu. Z. Krupsky. Kyiv, 2007. Funds of JSC Nadra Concern.
  13. Gofshtejn, I.  D. (1995). Geomorphological essay on the Ukrainian Carpathians. Kyiv: Naukova dumka.
  14. Gruzman, A. D., & Smirnov, S. E. (1982). Olistostrom in the Upper Krosno sub-suite of the Ukrainian Carpathians. DAN USSR. Ser. B. 10, 11–14.
  15. Gruzman, A. D., & Smirnov, S. E. (1985). Opistostroms of the Krosno suite of the Ukrainian Carpathians. DAN URSR. Ser. B., 4, 17–20.
  16. Kuzovenko, V. V., Zhygunova, Z. F., Bunda, V. A., Evtushko, T. L., Shlapinskij, V. E., & Shakin, A. V. (1982). Report on group geological survey at a scale of 1:50000 in the area of Vyshkov of the Ivano-Frankivsk and Transcarpathian Region of Ukr.S.S.R in 1978-1982 (sheets M-34-120-A,В, M-34-131-Б, M-34-132-A,B). Lviv. Funds of the State Enterprise Zakhidukrgeologia.
  17. Kuzovenko, V. V., Glushko, V. V., Myshkin, L. P., & Shlapinskyi, V. E. (1990). Report on the theme: Studies of geological-geophysical materials on the Skyba and Krosno zones of the Folded Carpathians with the purpose of revealing of objects prospective for oil and gas for 1988-1990, Lviv.
  18. Kuzovenko, V. V., & Shlapinskyi. V. E. (2007). On the nature and conditions of the placement of "cliffs" of Neocomian diabases in the Burkut nappe of the Ukrainian Carpathians. Proceedings of NTSh. Geol collection, 1, 40–49.
  19. Krupskyi, Yu. Z., Kurovets, I. M., Senkovskyi, Yu. M., Mykhailov, V. A., Chepil, P. M., Dryhant, D. M, Shlapinskyi. V. E., Koltun, Yu. V. … & Bodlak, V. P. (2014). . Unconventional sources of hydrocarbons in Ukraine: monograph in 8 volumes. V. 2 Western oil and gas region. NJSC Naftogaz Ukrainy and others. Kyiv: Nika-Centr.
  20. Malskaya, R. V. (1983). Tectonic lineaments in the Carpathian region. Oil and gas industry, 1, 19–21.
  21. Nakapelukh, M., Bubniak, I., Yegorova, T., Murovskaya, A., Gintov, O., Shlapinskyi, V., & Vikhot, Y. (2017). Balanced geological cross-section of the outer ukrainian carpathians along the pancake profile. Journal of Geodynamics, 108, 13-25. https://doi.org/10.1016/j.jog.2017.05.005
  22. Sandulescu, M., Micu, M., Bratu, E., Constannin, P., Popescu, O. (1987). Sur la presence du facies de Slons, dans la nappe de Tarcau, au nord de la vallee de la Moldova (Carpathes Orientales). Rev. Roum.Geol. Geoph. Geogr. – Serie Geologie, XXXI.
  23. Subbotin, S. I. (1955). The deep structure of the Soviet Carpathians. Kyiv: Publishing House of the Academy of Sciences of the Ukrainian SSR.
  24. Shakin, V. A., & Sandler, Ja. M. (1963). Gypsum in the Oligocene flysch of the Carpathians. Tr. UkrNIGRI. 6, 110–173.
  25. Shlapinskyi, V. E. (2009). Microfauna in the olistostormic formations in the Upper Cretaceous of the Goverla sub-nappe in the Yasinya area. Fossil fauna and flora of Ukraine: paleoecological and stratigraphic aspects: [collection of scientific works of IGS NAS of Ukraine]. [resp. ed. P. F. Gozhyk]. Kyiv
  26. Shlapinskyi, V. E. (1989). Geochemical anomalies of the Folded Carpathians and their relationship with petroleum bearing. Problems of geology and geochemistry of combustible minerals of the west of the Ukrainian SSR: abstracts of the reports. of the  rep. conf. (Lviv, October 2–6, 1989). III, 77–78.
  27. Shlapinskyi, V. E. (2012). Some issues of the tectonics of the Ukrainian Carpathians. Proceedings of NTSh, Geological collection, ХХХ, 48–68.
  28. Shlapinskyi, V. E. (2012). On the boundary between the Oligocene and the Miocene in the Boryslav-Pokutttya nappe of the Carpathian Foredeep and the Folded Carpathians. Proceedings of NTSh, Geological collection, ХХХ, 100–118.
  29. Shlapinskyi, V. E. (2014). Tectonic klippes in the upper reaches of streams Svidovets and Stanislaw (Gorna Tysa basin) – geoturistic objects. Carpathians Potential of the Cognitive Tourism. Edited by Ihor Bubniak and Andrzeу Solecki. Krosno, 77–81.
  30. Shlapinskyi, V. E. (2015). Complex assessment of oil and gas prospects of the frontal part of the Folded Ukrainian Carpathians. International scientific conference. Geology of Combustible Minerals: Achievements and Prospects, Kyiv, September 2-4, 2015
  31. Shlapinskyi, V. E. (2017). Prospects of oil and gas bearing of Verkhovyna-Yablunytsia area. International scientific conference devoted to the 100th anniversary of academician Grygoriy Nazarovych Dolenko. Geology and geochemistry of combustible minerals. 1–2 (170–171), 187–188.
  32. Stefanesku, M. (1980). Slon olistostrome:lithological, geometrical position, tectonic significance  // Materialy XI kongressa KBGA (litologija) Kyiv: Naukova. dumka.
  33. Tcarnenko, P. (1989). On the discoveries of tectonic remains in the Ukrainian Carpathians. XIV Congress of the KBGA, Sofia, abstracts, 458-461.
  34. Vyalov, O. S., Danysh, V. V, Tsarnenko, P. N. (1969). Some new ideas about the tectonics of the Eastern Carpathians. Geol. Magazine, 29, 5, 23-35.