Hassi Leila Fm
Period:
Cambrian
Age Interval:
Uncertain extent within Fortunian – Cambrian Stage 10.
Province:
Illizi Basin
Type Locality and Naming
Synonym: Unit II in the Illizi Basin (Benvegnù, 2020).
References: Hallett, 2002; Benvegnù, 2020
Lithology and Thickness
It is separated from the Pan-African basement by the Infratassilis Unconformity and it is dominated by transgressive medium to coarse-grained fluvial sandstones (Benvegnù, 2020).
Lithology Pattern:
Coarse-grained sandstone
Relationships and Distribution
Lower contact
It unconformably (Infratassilis Unconformity) overlies the Infra-Tassilian/Mourizidie Basement Complex.
Upper contact
It is conformably overlain by the In Kraf Fm.
Regional extent
Illize Basin of SE Algeria
GeoJSON
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Fossils
Age
Middle to Upper Cambrian? Base is above Great unconformity terminating “Infra-Cambrian (hence Ediacaran-earliest Cambrian) metamorphic complex. Therefore, onset put as within “middle Cambrian”. Very uncertain onset and termination!
Age Span:
Beginning stage:
Drumian
Fraction up in beginning stage:
0.00
Beginning date (Ma):
504.50
Ending stage:
Cambrian Stage 10
Fraction up in the ending stage:
1.0
Ending date (Ma):
486.85
Depositional setting
Fluvio-deltaic, to intertidal-subtidal, to offshore bars depositional setting (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 An unpublished MSc thesis at Universita’ degli Studi di Padova.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.