Morphometric analysis of pebbles in verification of transport processes and interpretation of palaeoenvironment: A case study from the Ogwashi Formation (Oligocene), Niger Delta Basin, Nigeria

• Autorzy: Ogbe Ovie B. , Osokpor Jerry , Emelue Chukwunomso V. , Ocheli Azuka

Identyfikatory

DOI

10.14746/logos.2023.29.1.02

• Języki publikacji: EN

Abstrakty

EN

The present paper discusses a palaeoenvironmental interpretation of the Oligocene Ogwashi Formation (Niger Delta Basin, Nigeria) through morphometric analysis of pebbles, a research method essentially depending on the quantitative evaluation of pebble size and shape which change during transport processes in a range of depositional environments. The relationship of bivariate and ternary-diagram plots of independent functions was determined from freshly exposed sandstone sections in quarries at Ibusa, near Asaba, Nigeria. The grain size of pebbles ranges from fine (11.00 mm) to very coarse (41.33 mm), with a mean size of 21.05 mm (coarse pebbles). A bivariate plot of the flatness index vs maximum projection sphericity index shows 37% of the pebbles to fall within a beach (marine) environment, and 33% within a fluvial environment; the remaining 30% are uncertain. The maximum projection sphericity index vs oblate-prolate index bivariate plot indicates that 47% of pebbles fall within a marine environment and 22% within a fluvial environment, while the remaining 31% are uncertain. The sphericity-form ternary diagram plot shows that the pebbles primarily comprise bladed, platy, very bladed and very platy of near-equal proportions with minor elongate and very elongate stones, which suggests that the pebbles are diverse in origin. The sphericity-form bivariate plot indicates that the pebbles are largely of disc and blade shapes with a minor number of spherical and rod shapes. The near-equal proportion of pebbles in different segments of the bivariate and ternary diagram plots, and the wide distribution of the pebble grain sizes and shapes suggest the Ogwashi Formation is composed of redeposited sediments that likely were transported and deposited in a mix of marine and fluvial settings with possible transitional environments. In other words, the pebbles can be interpreted as marine-influenced fluvial sediments in marginal-marine settings.

Słowa kluczowe

EN

grain morphometry; sandstone facies; bivariate plot; ternary diagram; mixed environments; Oligocene sediments

PL

morfometria; frakcja; piaskowiec; osady; Oligocen

• Wydawca: Uniwersytet im. Adama Mickiewicza. Instytut Geologii
• Czasopismo: Geologos
• Rocznik: 2023
• Tom: Vol. 29, No. 1
• Strony: 21--31
• Opis fizyczny: Bibliogr. 52 poz.

Twórcy

autor

Ogbe Ovie B.

• Department of Earth Sciences, Federal University of Petroleum Resources, PMB 1221, Effurun, Delta State, Nigeria

autor

Osokpor Jerry

• Department of Earth Sciences, Federal University of Petroleum Resources, PMB 1221, Effurun, Delta State, Nigeria

autor

Emelue Chukwunomso V.

• Department of Earth Sciences, Federal University of Petroleum Resources, PMB 1221, Effurun, Delta State, Nigeria
• Department of Hydrogeology and Hydrology, Delta State Ministry of Water Resources and Development, Asaba, Nigeria

autor

Ocheli Azuka

• Department of Geology, University of Delta, Agbor, Nigeria

Bibliografia

• Abdulkadir, T.A. & Abdullatif, O.M., 2013. Facies, depositional environments, reservoir potential and palaeogeography of the Cambro-Ordovician Dibsiyah Formation, Wajid outcrop belt, Saudi Arabia. Arabian Journal Science and Engineering 38, 1785–1806.
• Adeoye, M.O., Ndeze, C.K., Akande, S.O. & Ojo, O.J., 2016. Petrographic facies evaluation, provenance and depositional environment of the Oligocene – Miocene Ogwashi-Asaba Formation, southern Anambra Basin. Journal of Mining and Geology 52, 1–18.
• Arua, I., 1986. Paleoenvironment of Eocene deposits in the Afikpo syncline, southern Nigeria. Journal of African Earth Sciences 5, 279–284.
• Barudžija, U., Velić, J., Malvić, T., Trenc, N. & Božinović, N.M., 2020. Morphometric Characteristics, Shapes and Provenance of Holocene Pebbles from the Sava River Gravels (Zagreb, Croatia). Geosciences 10, 1–21.
• Bluck, B.J., 1967. Sedimentation of beach gravels: examples from South Wales. Journal of Sedimentary Petrology 37, 128–156.
• Brush, L.M., 1961. Drainage basins, channels, and flow characteristics of selected streams in Central Pennsylvania. U.S. Government Printing Office, pp. 145–181.
• Dobkins, J.E. & Folk, R.L., 1970. Shape development in Tahiti Nui. Journal of Sedimentary Petrology 40, 1167–1203.
• Ejeh, O.I., Akpoborie, I.A. & Etobro, A.A.I., 2015. Depositional setting of sandstones from the Oligocene-Miocene Ogwashi-Asaba Formation, Niger Delta Basin, Nigeria: Evidence from grain size analysis and geochemistry. Universal Journal of Geoscience 3, 71–82.
• Ekwenye, O.C. & Nichols, G.J., 2016. Depositional facies and ichnology of a tidally influenced coastal plain deposit: the Ogwashi Formation, Niger Delta Basin. Arabian Journal of Geosciences 9, 1–27.
• Ekwenye, O.C., Nichols, G. & Mode, A.W., 2015. Sedimentary petrology and provenance interpretation of the sandstone lithofacies of the Paleogene strata, south-eastern Nigeria. Journal of African Earth Sciences 109, 239–262.
• Elfrink, B. & Baldock, T. 2002. Hydrodynamics and sediment transport in the swash zone: a review and perspectives. Coast Engineering 45, 149–167.
• Els, B.G., 1988. Pebble morphology of an ancient conglomerate: the Middelvlei gold placer, Witwatersrand, South Africa. Journal of Sedimentary Petrology 58, 894–901.
• Gale, S.J., 1990. The shape of beach gravels. Journal of Sedimentary Petrology 60, 787–789.
• Gale, S.J. 2021. The shape of fluvial gravels: Insights from Fiji’s Sabeto River. Geosciences 11, 161.
• Hubert, F.L., 1968. Selection and wear of pebbles on gravel beaches. University of Groningen Geological Institute Publication, 190, 144 pp.
• Illenberger, W.K., 1991. Pebble shape (and size). Journal of Sedimentary Petrology 61, 756–767.
• Kogbe, C.A., 1976. The continental intercalaire in northwestern Nigeria. Journal of Mining and Geology 13, 45–50.
• Lewis, D.W. & McConchie, D., 1994. Analytical sedimentology. Earth Science, Springer, 206 pp.
• Lutig, G., 1962. The shape of pebbles in the continental, fluviatile and marine facies. International Association of Science Hydrology 59, 253–258.
• Madi, K. & Ndlazi, N.Z., 2020. Pebble morphometric analysis as signatures of the fluvial depositional environment of the Katberg Formation near Kwerela River around East London, Eastern Cape Province, South Africa. Arabian Journal of Geoscience 13, 235.
• Madukwe, Y. & Bassey, E., 2015. Geochemistry of the Ogwashi-Asaba Formation, Anambra Basin, Nigeria: Implications for provenance, tectonic setting, source area weathering, classification and maturity. International Journal of Science and Technology 4, 312–327.
• Murat, R.C., 1972. Stratigraphy and paleogeography of the Cretaceous and lower Tertiary in southern Nigeria. [In:] T.F.J. Dessauvagie & A.J. Whiteman (Eds): African Geology, University of Ibadan Press, Nigeria, pp. 251–266.
• Nichols, G., 2009. Sedimentology and stratigraphy. Blackwell Scientific Publications, Oxford, 419 pp.
• Nton, M.E. & Adamolekun, O.J., 2016. Sedimentological and geochemical characteristics of outcrop sediments of Southern Bida Basin, Central Nigeria: implications for provenance, paleoenvironment and tectonic history. Ife Journal of Science 18, 345–369.
• Nwajide, C.S., 1980. Eocene tidal sedimentation in the Anambra Basin, Southern Nigeria. Sedimentology Geology 25, 189–207.
• Nwajide, C.S., 2006. Anambra Basin of Nigeria: synoptic basin analysis as a basis for evaluating its hydrocarbon prospectivity. [In:] C.O. Okogbue (Ed.): Hydrocarbon potentials of the Anambra Basin: Geology, geochemistry and geohistory perspectives. Proceedings of 1st seminar organized by Petroleum Technology Development Fund Chair in Geology, University of Nigeria, Nsukka, pp. 1–46.
• Nwajide, C.S., 2013. Geology of Nigeria’s sedimentary basins. CSS Bookshops, Lagos, Nigeria, 565 pp.
• Nwajide, C.S. & Hoque, M., 1982. Pebble morphometry as an aid in environmental diagnosis: an example from the Middle Benue Trough. Journal of Mining and Geology 19, 114–120.
• Ocheli, A., Okoro, A.U., Ogbe, O.B. & Aigbadon, G.O., 2018. Granulometric and pebble morphometric applications to Benin Flank sediments in western Anambra Basin, Nigeria: proxies for paleoenvironmental reconstruction. Environmental Monitoring and Assessment 190, 1–17.
• Odumodu, C.F.R. & Israel, H.O., 2014. Pebble form indices as paleoenvironmental reconstruction tools for the Ogwashi–Asaba Formation, southeastern Nigeria. International Journal of Geology, Earth & Environmental Sciences 4, 149–159.
• Ogala, J.E., 2012. The geochemistry of lignite from the Neogene Ogwashi-Asaba Formation, Niger Delta Basin, southern Nigeria. Earth Sciences Research Journal 16, 151–164.
• Ogala, J.E., Adaikpoh, E.O, Omo-Irabor, O.O. & Onotu, R.U., 2010. Granulometric analysis and pebble morphometric studies as indicators of depositional environments of the sandstone facies around Okanyan and environs in the Benin Formation, Southwestern Nigeria. World Applied Sciences Journal 11, 245–255.
• Ogbe, O.B., 2021. Reservoir sandstone grain-size distributions: Implications for sequence stratigraphic and reservoir depositional modelling in Otovwe field, onshore Niger Delta Basin, Nigeria. Journal of Petroleum Science and Engineering 203, 108639.
• Ogbe, O.B. & Osokpor, J., 2021. Depositional facies, sequence stratigraphy and reservoir potential of the Eocene Nanka Formation of the Ameki Group in agu-Awka and Umunya, southeast Nigeria. Heliyon Elsevier 7, e05846.
• Okoro, A.U., Onuigbo, E.N., Akpononu, E.O. & Obiadi, I.I., 2012. Lithofacies and pebble morphogenesis: keys to paleoenvironmental interpretation of the Nkporo Formation, Afikpo Sub-Basin, Nigeria. Journal of Environment and Earth Science 2, 26–37.
• Olugbenro, R. & Nwajide, C.S., 1997. Grain size distribution and particle morphogenesis as signatures of depositional environments of Cretaceous (non-ferruginous) facies in the Bida Basin, Nigeria. Journal of Mining and Geology 33, 89–101.
• Oluwajana, A.O., Ugwueze, C.U., Ogbe, O.B. & Egunjobi, K.J., 2021. Pebble morphogenesis of the Cretaceous conglomerates from the Abeokuta Formation near the Oluwa River, Eastern Dahomey Basin, Southwestern Nigeria. Mining-Geology-Petroleum Engineering Bulletin 36, 93–104.
• Onyemesili, O.C. & Odumodu, C.F.R., 2019. Pebble morphometric study of the Ogwashi-Asaba Formation at Ubakala and environs in Southeastern Nigeria. Journal of Natural Sciences Research 9, 36–50.
• Osokpor, J. & Ogbe, O.B., 2019. Sequence stratigraphic signatures from Xen-1 well: key for understanding Cretaceous–Tertiary transitional events in the northwestern Niger Delta Basin, Nigeria. Petroleum and Coal 61, 860–880.
• Overare, B. & Osokpor, J., 2020. Providing clues on the paleo-weathering of Ogwashi-Asaba Formation, Niger Delta Basin: Evidence from geochemistry. Tropical Journal of Science and Technology 1, 74–92.
• Petters, S.W., 1991. Regional geology of Africa. Lecture Notes in Earth Sciences. Springer-Verlag, Berlin, 743 pp.
• Reyment, R.A., 1965. Aspects of the geology of Nigeria: The stratigraphy of the Cretaceous and Cenozoic deposits. Ibadan University Press, Ibadan, Nigeria, 145 pp.
• Sames, C.W., 1966. Morphometric data of some recent pebble associations and their application to ancient deposits. Journal of Sedimentary Petrology 36, 125–142.
• Short, K.C. & Stauble, A.J., 1967. Outline of geology of Niger Delta. American Association of Petroleum Geologist Bulletin 51, 761–779.
• Simpson, A., 1955. The Nigerian coalfield. The geology of parts of Onitsha, Owerri and Benue provinces. Geological Survey of Nigerian Bulletin, 24, 85 pp.
• Sneed, E.D. & Folk, R.L., 1958. Pebbles in the lower Colorado River, Texas: a study in particles morphogenesis. Journal of Geology 66, 114–150.
• Sremac, J., Velić, J., Bošnjak, M., Velić, I., Kudrnovski, D. & Troskot-Čorbić, T., 2018. Depositional model, pebble provenance and possible reservoir potential of Cretaceous conglomerates: Example from the southern slope of Medvednica Mt. (Northern Croatia). Geosciences 8, 456.
• Stratten, T., 1974. Notes on the application of shape parameters to differentiate between beach and river deposits in southern Africa. Transactions Geological Society of South Africa 77, 59–64.
• Tankard, A.J, Martin, K.A., Eriksson, D.K., Hobday, K.A., Hunter, D.R. & Minter, W.E.L., 1982. Crustal evolution of southern Africa: 3.8 billion years of earth history. Springer-Verlag, Heidelberg, 523 pp.
• Tattam, C.M., 1944. A review of Nigerian stratigraphy. Report of Geological Survey of Nigeria (1943), 27–46.
• Widera, M., 2010. The morphology of fossil pebbles as a tool for determining their transport processes. Annales Societatis Geologorum Poloniae 80, 315–325.
• Wilcock, D.N., 1971. Investigation into the relations between bedload transport and channel shape. Geological Society of America Bulletin 82, 2159–2176.

Uwagi

Opracowanie rekordu ze środków MNiSW, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2024).