Deliya info 1.2019 | oilandgasgeology

Якорь 1

S.V. Deliya, I.D. Agapitov, I.V. Kazora, L.A. Popova, I.N. Kerusov

Structure of Jurassic and Cretaceous formations in the south-western part of the Caspian Basin

DOI 10.31087/0016-7894-2019-1-62-71

The study purpose is to clarify geological structure of the Jurassic-Cretaceous formations in the above-salt series of the south-western Caspian oil and gas bearing basin. Main commercial oil and gas occurrence of this series is associated with the Jurassic terrigenous formations. High facies variability over the area and over the section is typical of the Upper Jurassic section. Sedimentation in the coastal-marine environment caused accumulation of both sandy and clayey varieties. The paper presents the results of studies of this pay zone conducted using an integrated interpretation of geological and geophysical information. In the course of this work, the authors analysed a body of published and archive information on geological structure and oil and gas occurrence in above-salt formations. Sequence stratigraphy analysis for the first time conducted for this series resulted in consideration of relative sea level variations within the study area; and first and second order sequences were identified. When interpreting seismic attributes, the authors took into account the regional sedimentation settings and factor of salt dome structures uplifting. As a result, information on spatial distribution of sand bodies was obtained, which may be of utmost interest in terms of future exploration activities. Outcome of the presented studies was an essential clarification of geological model of the Jurassic-Cretaceous formations in the south-western Caspian oil and gas bearing basin.

Key words: Caspian; Astrakhan arch; above-salt series; 3D common depth point method; wide-azimuth seismics; seismic interpretation; sequence stratigraphy; seismic facies analysis.

For citation: Deliya S.V., Agapitov I.D., Kazora I.V., Popova L.A., Kerusov I.N. Structure of Jurassic and Cretaceous formations in the south-western part of the Caspian Basin. Geologiya nefti i gaza. 2019;(1):62–71. DOI: 10.31087/0016-7894-2019-1-62-71.

References

1. Brodskii A.Ya., Voronin N.I., Mitalev I.A. Structure of Lower Carboniferous and Devonian formations and focus of petroleum exploration in the Astrakhan Arch. Oil and gas geology. 1994;(8):8–11.
2. Gabrielyants G.A., Dikenshtein G.Kh. , Kapustin I.N. Regional geology of oil and gas bearing territories in USSR. In: G.A. Gabrielyants, ed. Moscow: Nedra; 1991. 283 p.
3. Kalyagin S.M. Lithological and facies features of the Middle Jurassic pay zone in the south-western Caspian depression. Nauka: Poisk 2003. Issue 1. Astrakhan: AGTU 2003. pp. 239–243.
4. Muromtsev V.S. Electrometric geology of sand bodies — oil and gas stratigraphic traps. Leningrad: Nedra; 1984. 260 p.
5. Atlas of lithology and paleogeography, depth, palinspastic and geoecological maps of the Central Eurasia. In: S.Zh. Daukeeva et al., eds. Almaty: NII Prirodnykh Resursov YuGGEO; 2002. 26 p.
6. Vail P.R., Sangree J.B. Seismic Stratigraphy and Global Changes of Sea Level: Part 5. Chronostratigraphic Significance of Seismic Reflections: Section 2. Application of Seismic Reflection Configuration to Stratigraphic Interpretation. AAPG Memoir. 1977;(26):99–116.
7. Catuneanu О. Principles of Sequence Stratigraphy. New York: Elsevier; 2006. 386 p.
8. Hunt D., Tucker M.E. Stranded parasequences and the forced regressive wedge systems tract: deposition during base-level fall. Sedimentary Geology. 1992;(81):1–9. DOI:10.1016/0037-0738(92)90052-S
9. Haq B.U., Al-Qahtani A.M. Phanerozoic cycles of sea-level change on the Arabian Platform. GeoArabia. 2005;10 (2):127–160.