Analysis of the Jurassic microfauna and palinological complexes in the western and eastern parts of the Caspian Sea water area and Pre-Caspian territory
UDC: 551.762:563.12:561.252
DOI: -
Authors:
BOGUSLAVSKAYA ELENA V.
1,
MELIKHOVA ELIZAVETA V.1
1 LUKOIL-Engineering LLC, Volgograd, Russia
Keywords: microfauna, foraminifera, palynology, dinocysts, the Jurassic period, the Caspian Sea
Annotation:
Stratigraphic dissection of the Jurassic deposits of the studied well sections was performed on the basis of available paleontological data as well as by comparison with sections of adjacent wells in the Caspian Sea. According to paleontological data, the stratigraphic sequence, volumes and facets of stratons up to tiers and sub-tiers have been established in sections. In some places, the borders are very conditional. It is caused by the insignificant characterization of the core material and the presence of "dumb" samples in the sludge and core, or the presence of few biofossils, insufficiently preserved. The most reasonable and detailed data on the age of the Jurassic deposits of the studied samples were obtained based on the definitions of foraminifera. The definition of palynomorphs gave a wider age range. According to the results of complex micropaleontological studies (foraminifera, spores, pollen, dinocysts) in wells sections of the northwestern and eastern parts of the Caspian Sea, the Middle-Late Jurassic age of sediments has been substantiated by varying degrees of detail. The undifferentiated Baios-batian deposits of the Middle Jurassic, the Kellovian (as part of the Middle and Upper Kellovian sublayers), the Oxford, Kimmeridgian and Tithonian tiers of the Upper Jurassic system are distinguished.
Bibliography:
1. Azbel’ A.Ya. Agglyutiniruyushchie foraminifery iz yurskikh otlozheniy Mangyshlaka // Voprosy mikropaleontologii. – M.: Nauka, 1977. – Vyp. 20. – S. 157–171.
2. Evropeyskaya chast’ SSSR. Prakticheskoe rukovodstvo po mikrofaune SSSR / A.Ya. Azbel’, A.A. Grigyalis [i dr.] (red.). – T. 5. Foraminifery mezozoya. – L.: Nedra, 1991. – S. 64–76.
3. Grigyalis A.A. Foraminifery yurskikh otlozheniy yugo-zapadnoy Pribaltiki // Vil’nyus: Mokslas, 1985. – 240 s.
4. Il’ina V.P. Palinologiya yury Sibiri // Tr. In-ta geologii i geofiziki. – M.: Nauka, 1985. – Vyp. 638. – 238 s.
5. Pyatkova D.M., Permyakova M.N. Foraminifery i ostrakody yury Ukrainy: paleontologicheskiy spravochnik. – Kiev: Naukova dumka, 1978. – 289 s.
6. Smirnova O.I., Alekseev A.G., Smirnov M.V. Opyt kompleksirovaniya bio- i litostratigraficheskikh issledovaniy na primere verkhneyursko-nizhnemelovykh produktivnykh otlozheniy Prikumsko-Tsentral’no-Kaspiyskoy sistemy progibov i podnyatiy (akvatoriya Kaspiya) // Geologiya, geofizika i razrabotka neftyanykh mestorozhdeniy. – 2023. – № 10(382). – S. 16–24. – DOI: 10.33285/2413-5011-2023-10(382)-16-24
7. Litologo-fatsial’nye i paleogeograficheskie osobennosti verkhneyurskikh-nizhnemelovykh otlozheniy akvatorii Tsentral’nogo Kaspiya / O.I. Smirnova, A.G. Alekseev, E.Yu. Baraboshkin, M.V. Smirnov // Geologiya, geofizika i razrabotka neftyanykh mestorozhdeniy. – 2024. – № 10(394). – S. 5–14.
8. Unifitsirovannaya regional’naya stratigraficheskaya skhema yurskikh otlozheniy Vostochno-Evropeyskoy platformy: ob"yasnitel’naya zapiska / V.V. Mitta, A.S. Alekseev, S.M. Shik (red.). – M.: PIN RAN, FGUP "VNIGNI", 2012. – 64 s.
9. Riding J., Thomas J. Dinoflagellate cysts of the Jurassic System // A Stratigraphic Index of Dinoflagellate Cysts. – 1992. – Pp. 7–99.
10. Bailey D. BioStrat Stratigraphic Consultancy [Electronic resource]. – UK: Backbarrow, 2017. – URL: http://biostrat.org.uk (data obrashcheniya 12.02.2024)
Back to issue