The Famenian reservoir limestones on core petrophysical and electron spin resonance data (Southern slope of South-Tatarian Arc)

UDK: 551.7
DOI: 10.24887/0028-2448-2017-12-90-93
Key words: the Famenian oil saturated limestones, electron spin resonance (ESR) labels alternation
Authors: N.G. Nurgalieva, N.M. Khassanova, E.A. Anikina (Kazan (Volga Region) Federal University, RF, Kazan)

This paper presents core data on the composition and reservoir properties of the Famenian carbonate rocks in typical well section on the southern slope of South-Tatarian Arc. The core data include structures, minerals, reservoir properties measurements from previous studies and geochemical signs, just received by method of electron spin resonance (ESR).

Investigated intervals of 16 and 6 m thicknesses belong to the Famenian stage. The thickest interval is composed of grainstones and packstones. The second interval is composed of mainly packstones. The granulated fossils predominate in the studied limestones. Porous space is controlled by primary structure and also by leaching processes, secondary calcite mineralization and stylolites. The interval of 16 m concludes four layers on thin sections data and reservoir properties. The interval of 6 m belongs to one layer. ESR data have been obtained on 22 samples collected with step 0.6-1.2 m along the section. ESR spectra are characterized by narrow lines, pointing on marine genesis of carbonates. Paramagnetic centers of Mn2+ and SO2- have been observed as typical labels of rocks due by processes of carbonate sedimentation. A symbate behavior of Mn2+ and SO2- contents along the section correlates with reservoir characteristics increasing. A diverse behavior of Mn2+ and SO2- contents corresponds to reservoir characteristics decreasing. It can be explained by the unaltered carbonates in the first case and the altered carbonates in the second case because of the leaching, secondary crystallization, adding of the paramagnetic ions and redistribution of paramagnetic centers in new formed mineral phases.


1. Bulka G.R., Nizamutdinov N.M., Mukhutdinova N.G. et al., EPR probes in sedimentary rocks: the features of Mn2+ and free radicals distribution in the Permian formation in Tatarstan, Applied Magnetic Resonance, 1991, V. 2, no. 1, pp. 107–115.

2. Nurgalieva N.G., Galeev A.A., Issledovanie porod metodom ESR (Research of rocks by ESR method), Collected papers “Stratotipicheskiy razrez tatarskogo yarusa na reke Vyatke” (Stratigraphic section of Tatarian stage on the Vyatka River), Moscow: GEOS Publ., 2001, pp. 56–68.

3. Nurgalieva N.G., Khasanova N.M., Gabdrakhmanov R.R., Conditions of formation of  Urzhum stage deposits on ESR data (In Russ.), Uchenye zapiski Kazanskogo universiteta. Ser. Estestvennye nauki, 2010, V. 152, no. 1, pp. 226–234.

4. Fakhrutdinov E.I., Nurgalieva N.G., Khasanova N.M., Silant'ev V.V., The Lower Kazanian substage in the key section: lithologies and paleoenvironments based on the ESR data (In Russ.), Uchenye zapiski Kazanskogo universiteta, 2015, V. 157, no. 3, pp. 87–101.

5. Nurgalieva N.G., Anikina E.A., Khasanova N.M., The Tournesian reservoir limestones on core petrophysical and geochemical data (Southern slope of South-Tatarian Arc) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 2, pp. 46–48.

6. Nurgalieva N.G., Smelkov V.M., Kal'cheva A.V., Lithological and petrophysical features of Famenian and Tournesian carbonate reservoir rocks (In Russ.), Neft'. Gaz. Novatsii, 2013, no. 4, pp. 38–44.

7. Nurgalieva N.G., On influence of stylolites on reservoir properties of famennian carbonate rocks using Fourier spectra (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 4, pp. 16–19.

8. Dunham R.J., Classification of carbonate rocks according to depositional texture. In: Classification of carbonate rocks according to depositional texture, In: Classification of carbonate rocks – a symposium, AAPG Mem., 1962, V. 1, pp. 108–121.


To buy the complete text of article (a format - PDF) or to read the material which is in open access only the authorized visitors of the website can. .

Mobile applications

Read our magazine on mobile devices

Загрузить в Google play

Press Releases