Author(s): Ikhane Phillips R, Folorunso Adetayo F, Nton Matthew E, Oluwalaanu Josiah A, Oyebolu Olalekan O
The Turonian Nkalagu Formation exposed at NIGERCEM (Nigerian Cement Company) within the Lower Benue Trough was studied in this work in order to determine and establish the lithostratigraphic successions and reconstruct the paleoenvironment of the deposition. Two major litho-facies were delineated. The first is matrix-supported bioclastic shell lag wackestone facies which account for about 70% of the carbonates. The second is a massive fossil-poor micritic limestone. However, using the fossil contents, five distinct micro-biofacies were recognized namely: massive lithoclastic floatstone, bioclastic wakestone, siliceous fossil-poor limestone, bioclastic (bivalve debris) wackestone and bioclastic packstone. The litho-clast consists of probably shallow water transported materials while still in various degrees of lithification from shelf into deeper basin. Many of the lithoclasts are sub-angular whereas others have rounded shape. Textural gradient was upward fining and algae were completely absent which is typical of shallow calcareous marine sediments of the photic zone. The trends of the textural characteristics fall in pattern correlatable with the different facies outlined in the study. Thus, the evidence from this study has put Nkalagu Formation as a deposition in shallow marine environment but later displaced into relatively deeper water, probably that of the off-shelf zone, by some sedimentary flow mechanisms.
Turonian, paleoenvironmental reconstruction, lithoclasts, bioclasts, facies, Nkalagu Formation
- Al-Jaboury A. I and McCann T. (2008): The Middle Miocene Fatha (Lower Fans) Formation, Iraq. GeoArabia, Middle East Petroleum Geosecience. Vol. 13. No.3, p. 141-174
- Amajor, L. C. (1992): Storm Induced Turbidity-like Deposits: An example from the Turonian Eze-Aku Formation at Nkalagu, South eastern Nigeria. Nigeria Jour of Min and Geol., Vol. 28., 1 p. 7-17
- Banerjee, I. (1981): A subtidal bar model for the Eze â€“ Aku sandstones, Nigeria: Sed Geology, V. 25, p. 291 â€“ 309
- Dunham, R.J. (1962): Classification of Carbonate Rocks According to Depositional Texture. In: Ham (Ed.) Classification of Carbonate Rocks. Memoir, 1, AAPG, p. 103-121
- Fayose, E. A and de Klasz, I. (1976): Microfossils of the Ezeaku Formation (Turonian) at Nklalagu Quarry Eastern Nigeria, Nigerian Journ, Min. Geol., 13, p. 51 â€“ 61
- Jassim S. and Buday T. (2006): Latest Eocene â€“ Recent Mega sequence ApII. IN S.2 Jassim and J. C. Goff (Eds), Geology of Iraq. Dolin and Moravian Museum, Czech Republic, p. 169-184
- Murat, R. C. (1972): Stratigraphy and Paleogeography of the Cretaceous and Lower tertiary in Southern Nigeria; In T.F.J Dessauvagie, and A.J. Whiteman, eds., African Geology, Ibadan, Nigeria, Univ. Ibadan, p. 251 -266
- Peters, S. W. (1978a): Stratigraphic Evolution of the Benue Trough and its implication for the Upper Cretaceous Paleogeography of West Africa. Journal of Geology, 78, p.311 â€“ 312
- Peters, S. W. (1978b): Mid Cretaceous Paleoenvironments and Biostratigraphy of the Benue Trough: Nigeria Geol. Soc. Amer. Bull. 89, p.151-154
- Peters, S. W. (1980): Biostratigraphy of Upper Cretaceous Foraminifera of the Benue Trough, Nigeria. Journal. Forams, Research, 10: 191 â€“ 204
- Peters, S. W. and Ekweozor, C. M. (1982): Petroleum Geology of the Benue Trough and Southeastern Chad Basin, Nigeria. Bull Amer. Ass. Petroleum Geologist, 66, p. 1141-1149
- Reyment, R.A. (1965): Aspects of geology of Nigeria, Ibadan Univ. Press, Ibadan, 145p
- Simpson, A. (1955): The Nigeria coalfield: The geology of parts of Owerri and Benue Provinces, Bull, Geol. Surv. Nigeria, 24, p. 79-81
- Umeji, O. P. (1984): Ammonite Palaecology of the Exe Aku Formation Southeastern Nigeria: Nig. Jour. Mining and Geology. Vol. 21, p. 55-59
International Journal of Sciences is Open Access Journal.
This article is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) License.
Author(s) retain the copyrights of this article, though, publication rights are with Alkhaer Publications.