Mamu Fm
Period:
Cretaceous
Age Interval:
Campanian – Maastrichtian
Province:
Type Locality and Naming
It is in located near Enugu Cuesta.
References: 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
Lithology and Thickness
Consists of alternations of sandstones, mudstones, siltstones, coal seams, and rare shales with concretionary siderite and marcasite (Nwajide, 2013). The basal thickness is estimated to be 100m of the Coal Measures of the Anambra Basin by Nwajide (2013).
Lithology Pattern:
Coal
Relationships and Distribution
Lower contact
it conformably overlies the Nkporo Gr facies.
Upper contact
Overlain by the Ajali Fm
Regional extent
Anambra Basin
GeoJSON
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Fossils
Foraminifera (Haplophragmoides sp., Textularia, Ammomarginulina, Ammobaculites, Heterohelix globulosa) Ichnofissils (Thalassinoides, Teichichnus, Monocraterion), Ostracods (Bairdiasp., Paracyprisaugusta, Paracyprisnigeriensis) Palynomorphs (Achomospaera sp., Batiacasphaeridium, Tricolpites tiebaensis, Retitrocolpites clarensis, Staphanocolpites costatus).
Age
Late Cretaceous
Age Span:
Beginning stage:
Campanian
Fraction up in beginning stage:
0.85
Beginning date (Ma):
73.89
Ending stage:
Maastrichtian
Fraction up in the ending stage:
0.3
Ending date (Ma):
70.33
Depositional setting
Shallow Marine environment (Reyment, 1965; Courelet al., 1991); Transgressive
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.