On tectonics preconditions to form an oil and gas deposits

UDK: 553.98
DOI: 10.24887/0028-2448-2021-4-18-22
Key words: sedimentary cover, platform, small grabens, block, migration
Authors: E.V. Lozin (RN-BashNIPIneft LLC, RF, Ufa)

The influence of tectonics evolution of passive margin East-European platform (EEP) (within Bashkortostan) to form oil and gas deposits are discussed in the article. Studied territory during more 2.5 billion years was developing from primordial boulder-block framework Archean-Lower Proterozoic foundation to contemporary typical platform beds sedimentary rocks on the given crystal bed. Erode relief of crystalline basement, which constitutes sag along latitude, fill up with consolidative sediments and dipping step by step to East – to Pre-Urals foremost depression. Sedimentary cover contains Rifenian-Vendian and over Paleozoic sediments. The average thickness of Riphean-Vendian sedimentary cover makes up 7.0 km and its total thickness more than Paleozoic in 4.5 times. The average thickness of Paleozoic sediments is 3.0 km. By seismic and aeromagnetic data there were ascertain abatement of dislocating tectonics from the crystalline basement to Paleozoic deflections, which breaks be considered as a rarity. All oil and gas fields (more than 210) were ascertained in Paleozoic deflections, which contain seven Oil-Gas complexes. Its two terrigenous include 88% of total initial hydrocarbon reserves. The rentable masses of hydrocarbon in Riphean-Vendian sediments were not exposed because of fluid-cover absence up to the present time. During a long time, geological conception about classical monocline tectonic pattern of East margin EEP were corroborated by open oil and gas fields in plikative large-scale gross output structures Tuymasynian type. But at 1960s “small grabens”- regionally consedimentary grabens in terrigenous Devonian and postsedimentary grabens in Vendian-Paleozoic geological section are discovered. Than the echelon of consedimentary grabens, the horst-like zones – narrow semi-regional structures of conciseness are determined. The role of all list dislocates is containing in setting up absolutely new zones oil-gas bearing. Ones controlled oil fields with total reserves nearly a quarter of total initial hydrocarbon reserves of the Bashkir region. Detail analysis permits in any way examine well-known geological facts. The ambiguous function of regional and semi-regional dislocates were ascertained. On initial stage, they serve as conductor for vertical migration hydrocarbons and on the late-stage its function transformation to the (tectonic) screen with form oil deposits. Many oil fields settle down in dislocating zones. The efforts of press from the Urals were favourable this prose.


1. Trofimuk A.A., Neftenosnost' paleozoya Bashkirii (Oil content of the Paleozoic of Bashkortostan), Moscow: Gostoptekhizdat Publ., 1950, 248 p.

2. Trofimuk A.A., Usloviya obrazovaniya mestorozhdeniy Uralo-Volzhskoy neftenosnoy oblasti (Conditions for the formation of deposits in the Ural-Volga oil-bearing region), Part 1, Moscow: Publ. of Academy of Sciences of the USSR, 1955, 26 p.

3. Rozanov L.N., Istoriya formirovaniya tektonicheskikh struktur Bashkirii i prilegayushchikh oblastey (History of formation of tectonic structures of Bashkiria and adjoining areas), Ufa: Publ. of UfNII, 1957, 207 p.

4 Ovanesov G.P., Formirovanie zalezhey nefti i gaza v Bashkirii, ikh klassifikatsiya i metody poiskov (Formation of oil and gas deposits in Bashkiria, its classification and search methods), Moscow: Gostoptekhizdat Publ., 1962, 296 p.

5. Egorova N.P., Khalimov E.M., Ozolin B.V. et al., Zakonomernosti razmeshcheniya i usloviya formirovaniya zalezhey nefti i gaza Volgo-Ural'skoy oblasti (Regularities of location and conditions for the formation of oil and gas deposits in the Volga-Urals region), Part 4. Bashkirskaya ASSR (The Bashkir ASSR), Moscow: Nedra Publ., 1976, 240 p.

6. Lozin E.V., Geologiya i neftenosnost' Bashkortostana (Geology and oil content of Bashkortostan), Ufa: Publ. of BashNIPIneft', 2015, 704 p.

7. Lozin E.V., Anomal'no vysokoe plastovoe davlenie v neftyanykh zalezhakh v zonakh grabenoobraznykh progibov: svyaz' s mekhanizmom obrazovaniya zalezhey (Abnormally high reservoir pressure in oil reservoirs in zones of graben-like troughs: connection with the mechanism of reservoir formation), Proceedings of BashNIPIneft', 1992, V. 85, pp. 19–25.

8. Khat'yanov F.I., Paleorifty i transformnye mikrorazlomy na vostoke Russkoy plity (In Russ.), Metallogeniya i novaya global'naya tektonika, 1973, pp. 130-132.

9. Khat'yanov F.I., On the tectonic nature of buried Devonian micro-grabbers and the prospects for the search for oil-bearing structures in the southeast of the Russian platform (In Russ.), Geologiya nefti i gaza, 1971, no. 7, pp. 41–46.

10. Lozin E.V., Dragunskiy A.K., Age of graben-like troughs of Bashkiria (In Russ.), Izvestiya AN SSSR. Seriya geologicheskaya, 1988, no. 8, pp. 122–129.

11. Lozin E.V., On the mechanism of formation of sedimentary graben-like troughs in the east of the East European platform (In Russ.), Geologiya nefti i gaza, 1994, no. 2, pp. 16-17.

12. Lozin E.V., Racheva L.M., Specification of structure for post-sedimentary graben-like deflections in the platform using relevant seismic data (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 9, pp. 8–11.

13. Trofimov V.A., Korchagin V.I., Oil supply channels: spatial position, detection methods and methods of their activation (In Russ.), Georesursy, 2002, no. 31(9), pp. 18–23.

14. Utoplennikov V.K., Ogarinov I.S., Yarullin K.S., Controversial ideas about the structure and prospects of oil-bearing capacity of the Cis-Ural trough (In Russ.), Geologiya nefti i gaza, 1987, no. 3, pp. 53–55.

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