Geological environments forming the Eocene black-shale formation of the Silesian Nappe (Ukrainian Carpathians)

Received: February 19, 2019
Institute of Geology and Geochemistry of NAS of Ukraine
Institute of Geology and Geochemistry of NAS of Ukraine

Objective. To elaborate the geological structure and stratigraphy of the Eocene black shale formation of the Silesian Nappe, to recreate the depths and processes of its accumulation, and to reconstruct paleogeography and geodynamics of the Eocene sedimentatary Silesian Sub-basin. Methodology includes geological mapping, studing the lithostratigraphy and sedimentological features of the deposits (elements of Bouma sequence et al.) in a natural sedimentary succession, as well as paleobathimetric analyses of the foraminiferal assemblages. Results. The geological position of the studied sediments has been refined: the Eocene black-shale formation (Soimy Formation) developed within the Silesian Unit, and the variegated Paleocene-Eocene clayey deposits are distributed along the borders of the Silesian Unit in the Rozluch Structure (Subsilesian Nappe) and in the olistostrome strata. It is established, that the Soimy Formation is composed mainly of both products of the different density turbidity flows and the dark to black hemipelagic mud sediments. This formation was deposited in the Silesian Sub-basin at the bathyal-abyssal depths below the calcite compensation depth (CCD) which is indicated by the deepwater agglutinated foraminifera (assemblages “Glomospira-Haplophragmoides”, “Recurvoides”, “Glomospira”, “Rhabdammina-Reticulophragmium” and fauna “A”-type). The Silesian Sub-basin was limited by the uplifts such as Bukovets (branch of Silesian Kordiliera) and Subsilesian ones, on which in the Late Paleocene, the pelagic calcareous sediments enriched with planktonic foraminifera were deposited at the bathyal depths above the CCD and above the foraminiferal lysokline. In the Eocene on these uplifts, the clayey (hemi)pelagic deposits with the agglutinated foraminifera (assemblages “Rzehakina”, “Glomospira”, “Glomospira-Karrerulina” and fauna “B-type and “Rhabdammina-Reticulophragmium”) were settled below the CCD. In the Eocene, on the south-eastern wedge-shaped ending of the Silesian Sub-basin, there was a semi-isolated deep-water area, bounded on the northeast by the Sub-Silesian uplift, on the south-west by the Silesian (Bukovetsky) elevation, and on the south by the Fore-Marmarosh accretionary prism. Into this area, the circulation of the bottom-oxygen currents was limited and organic-enriched deposits (Soimy Formation) were deposited. At the end of Eocene, as a result of the subduction of the sedimentary basis of the Outer Carpathian Basin, the flysch strata was torn off from this basis and was thrust towards the platform and tectonically covered the submarine uplifts. Thrust movements caused the shallowing of the sedimentatary Outer Carpathian (including Silesian) Basin during the end of Eocene. Scientific novelty. A new paleogeographic model of the Eocene black shale (Soimy Formation) accumulation was proposed. According to the model, these deposits were accumulated by the turbidity flows and (hemi) pelagic sedimentation in the south-eastern semi-isolated deep-water section of the Silesian Sub-basin partly limited by uplifts. Practical Value. The geological characteristic of the Eocene black-shale formation, which may be potentially oil-generating, is given. Taking into account its availability, it can considerably expand the directions of the search of such work in the Carpathians.

1. Byzova, S. L., Beer, M. A. (1974). Main features of the tectonics of the Soviet part of the Flysch Carpathians. Geotectonics, (6), 82-94. (In Russian).
2. Csontos, L., & Vörös, A. (2004). Mesozoic plate tectonic reconstruction of the Carpathian region. Palaeogeography, Palaeoclimatology, Palaeoecology, 210, 1-56. doi:10.1016/j.palaeo.2004.02.033
3. Curtis, J. B., Kotarba, M. J., Lewan, M. D., Wiec1aw, D. (2004). Oil/source correlations in the Polish Flysch Carpathians and Mesozoic basement and organic facies of the Oligocene Menilite Shales: insights from hydrous pyrolysis experiments. Organic Geochemistry, 35, 1573-1596
4. Dabagyan, N. V., Kulchitskiy, Ya. O., Kuzovenko, V. V. & Shlapinsky, V.E. (1987). Key sections of the boundary layers of Upper Eocene-Lower Oligocene of the southern part of Skiba, Krosno and Chernogora zones. Paleontologicheskiy sbornik, 24: 27-33. (In Russian).
5. Glushhenko, L. A., Zhigunova, Z. F., Kuzovenko, V. V., Lozynjak, P. Ju., Temnjuk, F. P. (1980). Olistostrome in the Oligocene deposits of the Krosno (Silesian) zone of the Ukrainian Carpathians. In: Proceeding of the XI Congress of Carpathian-Balkan Geological Association. Lithology (pp. 55-64). Kyiv: Naukova dumka. (In Russian).
6. Glushko, V. V. & Kruglov, S. S. (Eds.). (1971). Geological structure and combustible minerals of the Ukrainian Carpathians. Moscow: Nedra.
7. Gradstein, F. M., Ogg, J. G., Schmitz, M. D., Ogg G.M. (Eds.). (2012). The Geologic Time Scale 2012. Elsevier, 2012.
8. Haigh, D. W. (1979). Global distribution patterns for mid-Cretaceous foraminiferids. Journal of Forest Research, 9, 29-40.
9. Hnylko, O. (2010) On the north-eastern boundary of the Krosno tectonic Zone in the Ukrainian Carpathians. Geology and geochemistry of combustible minerals, 151 (2), 44-57. (In Ukrainian).
10. Hnylko, O. (2011). Principles of distinguishing, features, classification and genesis of the olistostromes and melanges of the Ukrainian Carpathians. Bulletin of Lviv State University. Seria "Geology", 25: 20-35. (In Ukrainian).
11. Hnylko, O., & Hnylko, S. (2010). On geological composition of the Smozhe Structure from the Krosno Nappe of the Ukrainian Carpathians. Geology and geochemistry of combustible minerals, 152-153 (3-4), 57-72. (In Ukrainian).
12. Hnylko, O., & Hnylko, S. (2011). Stratigraphy and sedimentary environments of the Eocene flysch from the Krosno (Silesian) Nappe of the Ukrainian Carpathians. Geological Journal, 2, 12-24. (In Ukrainian).
13. Hnylko, S., & Hnylko, O. (2016). Foraminiferal stratigraphy and palaeobathymetry of Paleocene-lowermost Oligocene deposits (Vezhany and Monastyrets nappes, Ukrainian Carpathians). Geological Quarterly, 60 (1), 75-103. DOI:
14. Hnylko, O. M. (2000). Chaotic formation of south-western part of the Krosno Zone - the products of origin and development.
15. Hnylko, O. M. (2012). Tectonic zoning of the Carpathians in term's of the terrane tectonics Article 2. The Flysch Carpathian - ancient accretionary prism. Geodynamics. 14, 61-68. (In Ukrainian).
16. Kaminski, M. A., Gradstein, F. M. (2005). Atlas of Paleogene cosmopolitan deep-water agglutinated foraminifera. Grzybowski Foundation Special Publication, 10, 1-547.
17. Kaminski, M. A., Gradstein, F. M., Berggren, W. A., Geroch, S. & Beckmann, J. P. (1988). Flysch-type agglutinated foraminiferal assemblages from Trinidad: Taxonomy, stratigraphy ànd paleobathymetry. Abhandlungen der Geologischen Bundesanstalt, 41, 155-227.
18. Kaminski, M. A., Gradstein, F. M., Berggren, W. A. (1989). Paleogene benthic foraminifer biostratigraphy and paleoecology at Site 647, Southern Labrador Sea. Proceeding of the Ocean Drilling Program, Scientific Results, 105, 705-730.
19. Krupskyi, Yu. Z., Kurovets, I. M., Senkovskyi, Yu. M., Mykhailov, V. A., Chepil, P. M., Dryhant, D. M., Shlapinskyi, V. Ie., Koltun, Yu. V., Chepil, V. P., Kurovets, S. S., Bodlak, V. P. (2014). Unconventional sources of Hydrocarbons of Ukraine. Book II. Western gas-bearing region. Kyiv: Nika-Centre. (In Ukrainian).
20. Kotarba, M. J., Curtis, J. B., Lewan, M. D. (2009). Comparison of natural gases accumulated in Oligocene strata with hydrous pyrolysis from Menilite Shales of the Polish Outer Carpathians. Organic Geochemistry, 40, 769-783.
21. Kováč, M., Plašienka, D., Ján Soták, J., Vojtko, R., Oszczypko, N., Less, G., Ćosović, V., Fügenschuh, B., Králiková, S. (2016). Paleogene palaeogeography and basin evolution of theWestern Carpathians, Northern Pannonian domain and adjoining areas. Global and Planetary Change, 140, 9-27.
22. Kováč, M., Márton, E., Oszczypko, N., Vojtko, R., Hók, J., Králiková, S., Plašienka, D., Klučiar, T., Hudáčková, N., Oszczypko-Clowes, M. (2017). Neogene palaeogeography and basin evolution of the Western Carpathians, Northern Pannonian domain and adjoining areas. Global and Planetary Change, 155, 133-154.
23. Kuhnt, W., Kaminski, M. (1989). Upper Cretaceous deep-water agglutinated benthic foraminiferal assemblages from the western Mediterranean and adjacent areas. In J. Wiedmann (Ed.), Cretaceous of thewestern Tethys. Proceedings 3rd International Cretaceous Symposium, Tubingen 1987 (pp. 91-120). Stuttgart: Schweizerbart'sche Verlagsbuchhandlung.
24. Kuzovenko V. V. (Ed.). (2003). State Geological Map of Ukraine. Scale 1: 200,000. Carpathian series. Sheet "Snina": State Geological Survey. (In Ukrainian).
25. Murray, J. W. (1976). A method of determining proximity of marginal seas to an ocean. Marine Geology, 22, 256-284.
26. Olszewska, B. (1984). A paleoecological interpretation of the Cretaceous and Paleogene foraminifers of the Polish Outer Carpathians. Biuletyn Instytutu Geologicznego, 346, 7-62. (in Polish).
27. Olszewska, B. (1997). Foraminiferal biostratigraphy of the Polish Outher Carpathians: a record of basin geohistory. Annales Societatis Geologorum Poloniae, 67, 325-337.
28. Oszczypko, N. (2006). Late Jurassic-Miocene evolution of the Outer Carpathian fold-and-thrust belt and its foredeep basin (Western Carpathians, Poland). Geological Quarterly, 50 (1), 169-194.
29. Picha, F. J. and Golonka, J. (Eds.). (2005). Carpathian and their foreland: Geology and hydrocarbon resources. Tulsa, Oklahoma, U.S.A: AAPG Memory, 84.
30. Ponomaryova, L., Hnylko, S., Lemishko, O., Kylyanda, M., Marchenko, R, & Bratus, L. (2010). Some aspects of the reconstruction of sedimentary conditions in the Carpathian Basin on the basis of the foraminiferal study. In Report on Scientific work: O. S. Stupka, Z. M. Lyashkevych, O. M. Hnylko et al. Tectonic zoning of the Ukrainian Carpathians in the light of modern geological concepts (No. of State Registration 0106U002035), pp. 75-97. Lviv. Institute of Geology and Geochemistry of Combustible Minerals of the National Academy of Sciences.
31. Sachsenhofer, R. F., & Koltun, Y. V. (2012). Black shales in Ukraine - A review. Marine and Petroleum Geology, 31, 125-136. doi:10.1016/j.marpetgeo.2011.08.016
32. Ślączka, A. (2005). Bukowiec Ridge: a cordillera in front of the Dukla basin. Mineralica Slovaca , 3 (37), 255-256.
33. Vialov, O. S., Gavura, S. P., Danysh, V. V., Leshchuch, R. J., Ponomaryova, L. D., Romaniv, H. M., Tsarnenko, P. N., Tsizh, I. T. (1981). The History of the Geologic Development of the Ukrainian Carpathians. Kyiv: Naukova Dumka. (In Russian).
34. Waśkowska, A. (2015). Stratigraphy of the Hieroglyphic Beds with "Black Eocene" facies in the Silesian Nappe (Outer Flysch Carpathians, Poland). Annales Societatis Geologorum Poloniae, 85, 321-343. doi: