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Facies variability of pennsylvanian oil-saturated carbonate rocks (constraints from Bashkirian reservoirs of the south-east Tatarstan)

A.N. Kolchugin, G. Della Porta, V.P. Morozov, E.A. Korolev, N.V. Temaya, B.I. Gareev

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One of the strategic ways of the old oil-producing regions is to further prospecting for potentially promising areas for hydrocarbon. One of these exploration areas is the Volga-Ural region. These reservoirs consist of Carboniferous carbonate rocks, which contain high viscous hydrocarbons and are characterized by complex facies architecture and reservoir properties influenced by diagenesis. The high degree of facies variability in the studied area does not allow reliable distribution of potential reservoir rocks not only between different areas but even within the same oil field. Based on textural and compositional features of carbonate facies, 5 main facies associations were identified and characterized with respect to the depositional settings in the Bashkirian basin. The facies associations correspond to: distal middle ramp facies, open marine proximal middle ramp facies, high-energy innershoal facies, inner ramp facies of restricted lagoons, facies of affected by subaerial exposures. From west to east in the study the following trends in facies characterare identified: 1) a decrease open marine middle ramp facies and in the total thickness of the Bashkirian sections; 2) an increase in evidences of sub aerial exposures; 3) a decrease in the proportion of potential reservoir rocks. A general shallowing of the depositional setting was identified in an eastward direction, where potentially promising reservoir facies of shallow high-energy environments were replaced by facies of restricted lagoon and facies affected by subaerial exposures and meteoric diagenesis (palaeosols, dissolution). The applied approach based on detailed carbonate facies analysis allows predicting the distribution of potentially promising cross-sections within the region.

Bashkirian stage, carbonate ramp, facies, reservoirs, correlation


  • Badiozmani K., Mackenzie F.T., Thortenson D.C. (1977). Experimental carbonate cementation: salinity, temperature and vadose-phreatic effects. J.Sed.Petrol, 47(2), pp. 529-542.
  • Bishop J.W., Montañez I.P., Gulbranson E.L., Brenckle P.L. (2009). The onset of mid-Carboniferous glacio-eustasy: Sedimentologic and diagenetic constraints, Arrow Canyon, Nevada. Palaeogeography, Palaeoclimatology, Palaeoecology, 276(1-4), pp. 217-243.
  • Della Porta G., Kenter J.A.M. & Bahamonde J.R. (2004). Depositional facies and stratal geometry of an Upper Carboniferous prograding and aggrading high-relief carbonate platform (Cantabrian Mountains, N Spain). Sedimentology, 51(2), pp. 267-295.
  • Dunham R.J. (1962). Classification of carbonate rocks according to depositional texture. Classification of carbonate rocks: Simp. Amer. Assoc. Petrol. Geol. Mem. Ed. W.E.Ham, 1, pp. 108-121.
  • Galkin V.I., Efimov A.A. (2015). Development of forecasting models for assessing the oil mobility coefficient taking into account facies environments (for example, the Bsh Kokuysky deposit). Neftepromyslovoe delo = Oil Field Engineering, 8, pp. 11-15. (In Russ.)
  • Geology of Tatarstan: stratigraphy and tectonics (2003). Ed. B.V. Burov. Moscow: GEOS, 402 p. (In Russ.)
  • Gubareva B.C., Dalmatskaya I.I., Kotelnikova E.D. (1982). Bashkirian deposits in the east of the Russian plate. Scale of the Carboniferous system in the modern data. Moscow: Nauka, pp. 94-102. (In Russ.)
  • Hvorova I.V. (1958). Atlas of carbonate rocks of the middle and upper carbon of the Russian platform. Moscow: Academy of Sciences of the USSR Publ., 170 p. (In Russ.)
  • Immenhauser A., Hillgärtner H., Sattler U., Bertotti G., Schoepfer P. Homewood P., Vahrenkamp V., Steuber T., Masse J. P., Droste H., Taal-Van Koppen. J., Van der Kooij B., Van Bentum E., Verwer K., Hoogerduijn-Strating E., Swinkels W., Peters J., Immenhauser-Potthast I., Al-Maskery S. (2004). Barremian-Lower Aptian Qishn Formation, Haushi-Huqf area, Oman: A new outcrop analogue for the Kharaib/Shu’aiba reservoirs. GeoArabia, 9(1), pp. 153-194.
  • Khalymbadzha V.G. (1962). Middle Carboniferous Deposits of the Northern, Central, and Western Regions of Tataria. Kazan: KSU Publ., 239 p. (In Russ.)
  • Kochneva O.E., Koskov V.N. (2013). Lithological and facial correlation of Bashkirian carbonate deposits according to field geophysical studies. Neftepromyslovoe delo = Oil Field Engineering, 9, pp. 32-38. (In Russ.)
  • Kolchugin A., Della Porta G., Morozov V. (2017). Lower Pennsylvanian reservoir facies from the foreland basin carbonate ramp of the Volga-Ural region, east of Russian platform, Russian Federation. 33 International Meeting of Sedimentology. Abstract book. Toulouse, p. 467.
  • Kolchugin A.N., Immenhauser A., Walter B.F., Morozov V.P. (2016). Diagenesis of the palaeo-oil-water transition zone in a Lower Pennsylvanian carbonate reservoir: Constraints from cathodoluminescence microscopy, microthermometry, and isotope geochemistry. Marine and Petroleum Geology, 72, pp. 45-61.
  • Kolchugin, A.N., Morozov, V.P., Korolev, E.A., Eskin, A.A., Gazeeva, F.M. (2013). Typical sections of Bashkirian carbonate rocks and structure of oil deposits in the southeast part of the Republic of Tatarstan. Neftyanoe khozyaystvo = Oil Industry, 11, pp. 84-86. (In Russ.)
  • Mii H.-S., Grossman E.L., Yancey T.E., Chuvashov B., Egorov A. (2001). Isotopic records of brachiopod shells from the Russian Platform – Evidence for the onset of mid-Carboniferous glaciations. Chemical Geology, 175(1‑2), pp. 133-147.
  • Moore C.H. (1989). Carbonate Diagenesis and Porosity. Ser. Developments in Sedimentology, Vol. 46. Elsevier Publishing Co., 338 p.
  • Mukhametshin R.Z. (1982). The use of statistical methods for optimal partitioning and correlation of carbonate strata. Oil and gas geology and geophysics Ser. Moscow: VNIIOENG, No. 6, pp. 25-27. (In Russ.)

Anton N. Kolchugin
Kazan Federal University
18, Kremlevskaya st., Kazan, 420008, Russian Federation
Tel: +7(843)2337954

Giovanna Della Porta
Università Degli Studi di Milano
7, Via Festa del Perdono, Milan, 20122, Italy

Vladimir P. Morozov
Kazan Federal University
18, Kremlevskaya st., Kazan, 420008, Russian Federation

Eduard A. Korolev
Kazan Federal University
18, Kremlevskaya st., Kazan, 420008, Russian Federation

Natalya V. Temnaya
Kazan Federal University
18, Kremlevskaya st., Kazan, 420008, Russian Federation

Bulat I. Gareev
Kazan Federal University
18, Kremlevskaya st., Kazan, 420008, Russian Federation


For citation:

Kolchugin A.N., Della Porta G., Morozov V.P., Korolev E.A., Temaya N.V., Gareev B.I. (2020). Facies variability of pennsylvanian oil-saturated carbonate rocks (constraints from Bashkirian reservoirs of the south-east Tatarstan). Georesursy = Georesources, 22(2), pp. 29-36. DOI: