Soeka Fm
Period:
Jurassic
Age Interval:
Hettangian-Aalenian
Province:
Al Kufrah Basin
Type Locality and Naming
The name Soeka Formation was applied by Wacrenier (1958) and De Lestang (1965, 1968) to the continental Mesozoic rocks overlying the Madadi Formation in the southwestern Kufrah Basin near the Libyan-Chad border. (Tawadros 2011). [Lower formation of the Al Kufra Basin version of the Nubian Sandstone Gr.]
Synonym:
References: Tawadros, 2011
Lithology and Thickness
“It consists of white and varicolored, fine to coarse-grained, kaolinitic sandstones with varicolored silty shales at the base. Its thickness is approximately 300 m (984 ft).”
Lithology Pattern:
Clayey sandstone
Relationships and Distribution
Lower contact
It unconformably overlies the Madidi Fm (when present) or the older Dalma Fm.
Upper contact
Regional extent
Only the Al Kufrah Basin.
GeoJSON
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Fossils
Age
It is assigned as Jurassic. If the Lake Fm is considered to be independent and slightly less than half of the interval, then Hettangian through Aalenian (depending if it begins at base of Jurassic)
Age Span:
Beginning stage:
Hettangian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
201.36
Ending stage:
Aalenian
Fraction up in the ending stage:
1.0
Ending date (Ma):
170.90
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:
Tawadros, 2011, Geology of North Africa (book).