Enagi Siltstone Fm
Period:
Cretaceous
Age Interval:
Early –Mid Maastrichtian
Province:
Bida Basin- North and Central
Type Locality and Naming
This outcrop is exposed 6km east of the Enagi town at 9°8ꞌN and 5°35ꞌE (Whiteman, 1982; Nwajide, 2013).
Reference section: Reyment,1965; Adeleye,1975; Dessauvagie, 1975; Kogbe, 1976; 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
[Fig. 1 Stratigraphic successions in the Mid-Niger Basin (also known as Bida or Nupe Basin)]
Lithology and Thickness
It consists of siltstones and subordinate sandstones, claystones and siltstones/sandstone intermix (Nwajide, 2013).Mineral assemblage consists mainly of quartz, feldspars and clay minerals (Obaje, 2009). This formation is the lateral equivalent of the Patti Fm of South Bida subbasin (Jones, 1955 and 1958) and varies in thickness from as low as 9m to over 60m.
Lithology Pattern:
Siltstone
Relationships and Distribution
Lower contact
Lies above the Sakpe Ironstone Fm (Sakpe Fm)
Upper contact
Overlies the Batati Ironstone Fm
Regional extent
Central/Northern Bida Basin
GeoJSON
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Fossils
Fossil leaf impressions and rootlets have been found within the formation.
Age
Late Cretaceous (early-middle Maastrichtian)
Age Span:
Beginning stage:
Maastrichtian
Fraction up in beginning stage:
0.25
Beginning date (Ma):
70.64
Ending stage:
Maastrichtian
Fraction up in the ending stage:
0.5
Ending date (Ma):
69.11
Depositional setting
Continental facies of extensive delta; flood plain (Adeleye, 1972); or lacustrine, ponded marginal/transitional setting (Nwajide, 2013)
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.