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Kerb En Naga Formation
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Kerb En Naga Fm base reconstruction

Kerb En Naga Fm

Period: 
Devonian

Age Interval: 
Middle – Late Famennian


Province: 
Tindouf Basin

Type Locality and Naming

Djebilet-Yetti subbasin (exposed on northwest margin of Tindouf Basin)

Synonym:

References: Guerrak, 1989

[Fig. 1: Geological map of the Tindouf Basin region. (from Guerrak, 1989).]

[Fig. 2: Location of the Tindouf Basin Province, North Africa, and the six assessment units (AUs) (USGS, 2019).]

[Fig. 3: Stratigraphic column of the Tindouf Basin region (Guerrak, 1989).]

[Fig. 4: Stratigraphic correlation of the northern and southern flanks of the Tindouf Basin (Guerrak, 1989).]

[Fig. 5: Stratigraphic column of the study area (redrawn after Guerrak, 1988a).]


Lithology and Thickness

The Kerb En Naga Fm is about 100-140m thick, and is made up of siltstones and shales (Guerrak, 1989).


Lithology Pattern: 
Siltstone


Relationships and Distribution

Lower contact

Conformably overlies the Oued Ghazal Fm

Upper contact

Conformably underlies the Kerb Es Slouguia Fm

Regional extent

Extends throughout southern flanks of the Tindouf Basin, and Djebilet-Yetti subbasin (exposed on northwest margin of Tindouf Basin)


GeoJSON

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Fossils


Age 

Middle – Late Famennian

Age Span: 

    Beginning stage: 
Famennian

    Fraction up in beginning stage: 
0.5

    Beginning date (Ma): 
365.20

    Ending stage: 
Famennian

    Fraction up in the ending stage: 
1.0

    Ending date (Ma):  
359.30

Depositional setting


Depositional pattern:  


Additional Information


Compiler:  

Enam O. Obiosio, Solomon Joshua Avong and Henry Nasir Suleiman (2024) - Stratigraphic Lexicon compiled from the following books:

Andrea Ciampalini, Francesca Garfagnoli, Benedetta Antonielli, Chiara Del Ventisette & Sandro Moretti (2012) Photo-lithological map of the southern flank of the Tindouf Basin (Western Sahara), Journal of Maps, 8:4, 453-464, DOI: 10.1080/17445647.2012.746947

Guerrak S. (1989): Time and space distribution of Palaeozoic oolitic ironstones in the Tindouf Basin, Algerian Sahara. In: Young, T. P. & Taylor, W. E. G. (eds), 1989: Phanerozoic Ironstones

Geological Society Special Publication 46, pp. 197-212

Guerrak S. (1988a): Geology of the Early Devonian oolitic iron ore of the Gara Djebilet field. Saharan Platform, Algeria. Ore Geology Reviews, (In Press).