Alhamra Gr
Period:
Cretaceous
Age Interval:
Turonian – Maastrichtian.
Province:
Oued Mya Basin, Ghadames Basin
Type Locality and Naming
Synonym: Al Hambra Gr, Al Hamra Gr (mis-spelled?; USGS-Klett 2000), Alhambra Fm. (Bora and Dubey, 2015).
References: Bora and Dubey, 2015
Lithology and Thickness
The base of the Alhambra Gr is characterized by shale that laterally transitions into sandstone. On this unit is a thick section of limestones that is capped by a thin shale layer. The top of the group is truncated by the Alpine Unconformity (Alpine Orogeny) (Bora and Dubey, 2015).
Lithology Pattern:
Clayey limestone
Relationships and Distribution
Lower contact
It conformably overlies the Nefusa Gr.
Upper contact
-NA- Basin surface.
Regional extent
It extends throughout the Oued Mya and Ghadames Basin.
GeoJSON
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Fossils
Age
Turonian-Maastrichtian (into earliest Cenozoic?) on diagram of USGS-Klett (2000) (used here), although another source suggests base is base-Cenomanian.
Age Span:
Beginning stage:
Turonian
Fraction up in beginning stage:
0.00
Beginning date (Ma):
93.90
Ending stage:
Maastrichtian
Fraction up in the ending stage:
1.0
Ending date (Ma):
66.04
Depositional setting
Depositional pattern:
Additional Information
:
Compiler:
s:Enam O. Obiosio, Solomon Joshua Avong and Henry Nasir Suleiman (2024) - Stratigraphic Lexicon compiled from the following books:Bora, D., Dubey, S. (2015): New insight on petroleum system modeling of Ghadames basin, Libya. Journal of African Earth Sciences, 112: pp.111-128. http://dx.doi.org/10.1016/j.jafrearsci.2015.08.020
T.R. Klett (2000): Total Petroleum Systems of the Trias/Ghadames Province, Algeria, Tunisia, and Libya - The Tanezzuft-Oued Mya, Tanezzuft-Melrhir, and Tanezzuft-Ghadames. U.S. Geological Survey Bulletin, 2202-C.