No.3(47),2026 PP.52-80

Neftyanaya provintsiya No. 3(47), 2026

Facies-driven strategy for further exploration and development of complex terrigenous deposits of the Bobrikovsky horizon: A case study of the Block 024 in the marginal zone of the Romashkino field, Republic of Tatarstan

T.A. Safiullin, A.A. Nazarov, V.A. Dekhtyrev, E.K. Siraev, V.A. Lagutaev
DOI: https://doi.org/10.25689/NP.2026.3.52-80

Abstract

This paper presents a detailed facies analysis and a technical justification for the development strategy of the Bobrikovsky horizon (C₁br) within Block 024, located in the marginal zone of the Romashkino field (Republic of Tatarstan). Drawing on data from 23 wells, the study integrates three independent classification methods: Muromtsev’s morphological analysis of SP curves, GR curve motif analysis according to Nazeer et al., and cross-plot analysis of reservoir properties. The findings indicate that the horizon was formed by a meandering alluvial system, within which five distinct facies types were identified. A key geological contribution of this work is the documentation of lateral paleochannel migration between individual reservoir units. By combining this facies model with hydrodynamic parameters, we propose a conceptual development framework. The strategy involves positioning production wells along the stable axis of the paleochannel, while implementing a combined pressure maintenance system that integrates edge waterflooding with intra-channel injection. This approach creates hydrodynamic support and is expected to improve displacement front control; the proposed scheme is conceptual and requires verification against actual field performance data.

Key words:

Bobrikovsky horizon, facies analysis, paleochannel migration, reservoir heterogeneity, mobility ratio, pressure maintenance system (PMS), intra-channel injection, Romashkino field

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Authors

T.A. Safiullin, category I engineer, TatNIPIneft Institute – PJSC TATNEFT
88 Telmana St., Almetyevsk, 423462, Russian Federation
E-mail: SafiullinTA@tatneft.ru

A.A. Nazarov, department head, department of geological modeling, TatNIPIneft Institute – PJSC TATNEFT
88 Telmana St., Almetyevsk, 423462, Russian Federation
E-mail: NazarovAA@tatneft.ru

V.A. Dekhtyarev, division head, geology and geological modeling division, TatNIPIneft Institute – PJSC TATNEFT
88 Telmana St., Almetyevsk, 423462, Russian Federation
E-mail: DekhtyarevVA@tatneft.ru

E.K. Siraev, department head, department of data analysis and initial model calibration,
TatNIPIneft Institute – PJSC TATNEFT
88 Telmana St., Almetyevsk, 423462, Russian Federation
E-mail: SiraevEK@tatneft.ru

V.A. Lagutaev, Lead Specialist of the Competence Center Directorate for "Integrated Corporate Systems and CTS", LLC LUKOIL-Technologies; Almetyevsk State Technological University – Higher School of Petroleum
48, 2-ya Brestskaya St., Moscow, 125047, Russian Federation
E-mail: Vladimir.An.Lagutaev@lukoil.com

For citation:

T.A. Safiullin, A.A. Nazarov, V.A. Dekhtyrev, E.K. Siraev, V.A. Lagutaev Fatsial'no-oriyentirovannaya strategiya dorazvedki i razrabotki slozhnopostroyennykh terrigennykh za-lezhey bobrikovskogo gorizonta (na primere bloka **024 v krayevoy zone Romashkinskogo mestorozhdeniya Respubliki Tatarstan) [Facies-driven strategy for further exploration and development of complex terrigenous deposits of the Bobrikovsky horizon: A case study of the Block 024 in the marginal zone of the Romashkino field, Republic of Tatarstan]. Neftyanaya Provintsiya, No. 3(47), 2026. pp. 52-80. DOI https://doi.org/10.25689/NP.2026.3.52-80. EDN WKBSSR (in Russian)

© Non-governmental organization Volga-Kama Regional Division of the Russian Academy of Natural Science, 2015-2026 All the materials of the journal are available under the Creative Commons Attribution 4.0 License (https://creativecommons.org/licenses/by/4.0/)

Key words: Bobrikovsky horizon, facies analysis, paleochannel migration, reservoir heterogeneity, mobility ratio, pressure maintenance system (PMS), intra-channel injection, Romashkino field

Key words:

Bobrikovsky horizon, facies analysis, paleochannel migration, reservoir heterogeneity, mobility ratio, pressure maintenance system (PMS), intra-channel injection, Romashkino field