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Ghezziane Formation
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Ghezziane Fm base reconstruction

Ghezziane Fm

Period: 
Cambrian; Ordovician

Age Interval: 
Fortunian-Hirnantian


Province: 
Tindouf Basin

Type Locality and Naming

Djebilet-Yetti subbasin (exposed on northwest margin of Tindouf Basin). Also known as the Tindouf 1 (Ciampalini et al., 2012), and it was first described by Guerrak (1988a).

Synonym: Tindouf 1

References: Guerrak, 1988a; Ciampalini et al., 2012

[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 Ghezziane Fm is about 0-70m thick and is made up of layered and fractured quartz-rich sandstone (Guerrak, 1989; Ciampalini et al., 2012)


Lithology Pattern: 
Sandstone


Relationships and Distribution

Lower contact

It non-conformably overlies the Yetti Fm of Precambrian Granites.

Upper contact

It is conformably overlain by the Sebkha Mabbes Fm.

Regional extent

It is exposed across the entire width of the southern part of the basin (Ciampalini et al., 2012), and Djebilet-Yetti subbasin (exposed on northwest margin of Tindouf Basin)


GeoJSON

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Fossils


Age 

Fortunian-Hirnantian (uncertain for this relatively thin sandstone facies)

Age Span: 

    Beginning stage: 
Fortunian

    Fraction up in beginning stage: 
0.00

    Beginning date (Ma): 
538.80

    Ending stage: 
Hirnantian

    Fraction up in the ending stage: 
1.0

    Ending date (Ma):  
443.07

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).