In Kraf Fm
Period:
Ordovician
Age Interval:
Tremadocian.
Province:
Illizi Basin
Type Locality and Naming
Synonym: Unit III-1 in Illizi Basin (Benvegnù, 2020)
References: Benvegnù, 2020
Lithology and Thickness
It is made up of shallow-marine sandstone and maximum flooding shales with dark gray silty sequences containing trace fossils representing a marine transgressive unit (Benvegnù, 2020).
Lithology Pattern:
Clayey sandstone
Relationships and Distribution
Lower contact
It conformably overlies the Hassi Leila Fm.
Upper contact
It is conformably overlain by the Hamra Fm.
Regional extent
Illize Basin of SE Algeria
GeoJSON
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Fossils
Trace fossils.
Age
Age Span:
Beginning stage:
Tremadocian
Fraction up in beginning stage:
0.00
Beginning date (Ma):
486.85
Ending stage:
Tremadocian
Fraction up in the ending stage:
1.0
Ending date (Ma):
477.08
Depositional setting
Shallow marine (Benvegnù, 2020).
Depositional pattern:
Additional Information
Compiler:
Enam O. Obiosio, Solomon Joshua Avong and Henry Nasir Suleiman (2024) - Stratigraphic Lexicon compiled from the following books:Benvegnù I. (2020): Thermal Evolution of Paleozoic and Triassic Reservoir Rocks in the Ghadames-Illizi Basin (Algeria). An unpublished MSc thesis at Universita’ degli Studi di Padova.
T.R. Klett (2000): Province, Algeria, Tunisia, and Libya - The Tanezzuft-Oued Mya, Tanezzuft-Melrhir, and Tanezzuft-Ghadames. U.S. Geological Survey Bulletin, 2202-C.