K1 Fm
Period:
Cretaceous
Age Interval:
Early Cretaceous (6, 7b)
Province:
East Niger Rift Basin - Termit Sub-basin, East Niger Rift Basin - Ténéré Sub-basin
Type Locality and Naming
Subsurface: Wells of the Termit sub-basin. Ahmed et al., 2020. [Do not confuse this K1 Fm with the K1 Member of the Birni N’Konni Fm. It is highly recommended that a new name be assigned to this formation by the oil companies to reflect its uniqueness.]
Equivalent(s): This sub-surface formation correlates with the surface Tégama Gr, Téfidet Gr, Dibella Fm, Achegour Fm, Fachi Fm, Tiffa Fm.
Lithology and Thickness
Restricted terrigenous sediments of gray lacustrine mudstone. 300-2500 m thick.
Lithology Pattern:
Gypsiferous claystone
Relationships and Distribution
Lower contact
Underlying is Precambrian basement
Upper contact
Overlying unit is the Donga Fm
Regional extent
East Niger Rift Basin - found only in the western part of the Termit and the Ténéré Sub-Basins
GeoJSON
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Fossils
Age
Age Span:
Beginning stage:
Aptian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
121.40
Ending stage:
Albian
Fraction up in the ending stage:
1.0
Ending date (Ma):
100.50
Depositional setting
Continental – Alluvial, Fluvial, Lacustrine
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)