Zone de Passage Formation

Zone de Passage Fm

Period:

Silurian

Age Interval:

Pridoli (?).

Province:
Oued Mya Basin

Type Locality and Naming

Synonym:

References: Klett, 2000.

Lithology and Thickness

The Zone de Passage Fm is made up of sandstones and mudstones, and it is the lateral equivalent of the Akakus Fm. of the Ghadames Basin (Klett, 2000).

Lithology Pattern:

Clayey sandstone

Relationships and Distribution

Lower contact

It conformably overlies the Oued Imirhou Fm. in the Oued Mya (Triassic) Basin, and conformably overlies the Hot Shales Fm. in the Ahnet-Mouydir Basin.

Upper contact

It is unconformably overlain by the Hassi Tabankort Fm (Late Silurian-Early Devonian Unconformity – Klett, 2000), and it is unconformably overlain by the Oued Samene Fm. in the Ahnet-Mouydir Basin.

Regional extent

The term, and approximately same age span, is also used for an upward change from claystone into overlying sandstone in the Ahnet and Mouydir basins in NW Africa (which are temporarily on a different website – northafricalex.geolex.org. This extent is not added here with the Oued Mya basin version.

GeoJSON

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Fossils

Age

Age Span:

Beginning stage:

Pridoli

Fraction up in beginning stage:

0.00

Beginning date (Ma):

422.73

Ending stage:

Pridoli

Fraction up in the ending stage:

1.0

Ending date (Ma):

419.00

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:

Baouche, R., Ganguli, S. S., Sen, S., Radwan A. E. (2023): Assessment of reservoir stress state and its implications for Paleozoic tight oil reservoir development in the Oued Mya Basin, northeastern Algerian Sahara. Geosystems and Geoenvironment 2: pp.1-18. https://doi.org/10.1016/j.geogeo.2022.100112

Fadila B. (2004): Reservoir Characterization and Reservoir Modeling in the Northwestern Part of Hassi Massaoud Field Algeria. A PhD thesis at the University of Hamburg, Hamburg, Germany.

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.

Kraouia et al., (2023): Ordovician–Upper Silurian–Triassic Petroleum System Assessment in the Chotts Area. In S. Khomsi and F. Roure (eds.), Geology of North Africa and the Mediterranean: Sedimentary Basins and Georesources, Regional Geology Reviews, https://doi.org/10.1007/978-3-031-18747-6_7