Akinbo Fm
Period:
Paleogene
Age Interval:
Paleocene
Province:
Dahomey Basin
Type Locality and Naming
The formation was formalized by Ogbe (1972) and the type locality of the formation is in Ewekoro Quarry and named after a village 2.5km west of Ewekoro (Nwajide, 2013)
References: Reyment, 1965; Adeleye, 1975; Kogbe,1976; Dessauvagie, 1975; Petters, 1978; Offodile, 1980; Whiteman, 1982; Benkhelil, 1989; Okosun, 1992; Guiraud, 1993; Akande et al., 1998; Zaborski et al., 1998; Jauro et al., 2007; Obaje, 2009; Nwajide, 2013
Lithology and Thickness
This clay-rich formation is richly fossiliferous and contains pyrite crystals and spherulitic iron ore. The upper parts tend to lose lamination and become sandy, passing gradationally into massive mudstone. The topmost part is a sandy bed, which attains an abnormal thickness of 2.4km (??) in the northeast of Ewekoro quarry.
Lithology Pattern:
Claystone
Relationships and Distribution
Lower contact
Ewekoro Fm (unconformable)
Upper contact
Oshosun Fm (Gradational boundary)
Regional extent
Dahomey Basin
GeoJSON
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Fossils
foraminifera
Age
Paleocene (unconformity at base => left schematic gap of Lower Selandian)
Age Span:
Beginning stage:
Selandian
Fraction up in beginning stage:
0.5
Beginning date (Ma):
60.45
Ending stage:
Ypresian
Fraction up in the ending stage:
0.0
Ending date (Ma):
56.00
Depositional setting
Deep marine depositional environment
Depositional pattern:
Additional Information
Compiler:
Enam O. Obiosio, Solomon Joshua Avong and Henry Nasir Suleiman (2024)- Stratigraphic Lexicon compiled from the following books:Nigeria: Its Petroleum Geology, Resources and Potential, by Arthur Whiteman, 1982; (Volume 1) Published by Graham and Trotman Ltd.A review of the Cretaceous System in Nigeria by P. M. Zaborski (1998) In Africa Geoscience Review, Vol.5, No.4, pp385-483
Geology and Mineral Resources of Nigeria by Nuhu George Obaje, Published by Springer-Verlag Berlin Heidelberg 2009; http://www.springer.com/series/772
Geology of Nigeria Sedimentary Basins, Nwajide C. S., 2013; Published by CSS Bookshops Limited, Lagos Nigeria.