Dembaba Fm
Period:
Carboniferous
Age Interval:
Moscovian - Gzhelian
Province:
Murzuq Basin, Ghadames Basin
Type Locality and Naming
It was originally defined by Lelubre (1952) for a series of mainly carbonate rocks overlying the Assedjefar Formation in the Hamadat Tanghirt area (Hallett, 2002).
Synonym:
References: Lelubre, 1952; Mamgian, 1980; Hallett, 2002; Alkhalas, 2006
Lithology and Thickness
In the type area the Dembaba Formation consists of about 40m of gypsiferous claystone in the lower part, with a grayish blue limestone within the lower 10m above the base, containing stromatolitic structures (Alkhalas, 2006). The upper part of the Dembaba Formation in the type area consists of about 60m of light "grau dolomits" and highly fossiliferous dolomitic limestone with thin interbeds of claystone, capped by slumped limestone (Mamgian, 1980).
Lithology Pattern:
Clayey limestone
Relationships and Distribution
Lower contact
It conformably overlies the Assedjefar Fm.
Upper contact
It is conformably overlain by the Tiguentourine Fm.
Regional extent
It is present in the Murzuq and Ghadames Basins.
GeoJSON
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Fossils
Age
Age Span:
Beginning stage:
Moscovian
Fraction up in beginning stage:
0.00
Beginning date (Ma):
315.15
Ending stage:
Gzhelian
Fraction up in the ending stage:
0.00
Ending date (Ma):
303.68
Depositional setting
marine (Alkhalas, 2006)
Depositional pattern:
Additional Information
Compiler:
Enam O. Obiosio, Solomon Joshua Avong and Henry Nasir Suleiman (2024) - Stratigraphic Lexicon compiled from the following books: