Bilma Fm
Period:
Cretaceous
Province:
East Niger Rift Basin - Bilma Sub-basin
Type Locality and Naming
The Bilma cliff (or cuesta)
References: Plauchut et al., 1959; Faure, 1966; Fabre et al., 1983; Meister et al., 1994.
Synonym: Equivalent(s): Galhama Fm, Emi-Bao Fm, Termit Fm.
Lithology and Thickness
Brown sandstones, sometimes coarse with cross-bedded stratifications with intercalations of white kaolinitic clays. Its thickness 250-300 m.
Lithology Pattern:
Sandstone
Relationships and Distribution
Lower contact
Underlying unit is the Kafra Fm
Upper contact
None
Regional extent
East Niger Rift Basin - Bilma Sub-basin - South
GeoJSON
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Fossils
The ferruginous levels show plant debris; Dadoxylon (Araucarioxylon) sp.
Age
Late Cretaceous (Maastrichtian - Paleocene)
Age Span:
Beginning stage:
Maastrichtian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
72.17
Ending stage:
Thanetian
Fraction up in the ending stage:
1.0
Ending date (Ma):
56.00
Depositional setting
Continental
Depositional pattern:
Additional Information
Compiler:
Jacques LeBlanc (2022), Stratigraphic Lexicon: The Sedimentary Formations of The Republic of Niger, Africa. Colnes Publishing (Tallin, Estonia), 365 pp. https://doi.org/10.47909/978-9916-9760-6-7 (or via https://sites.google.com/site/leblancjacques)