Bir Tlacsin Formation

Bir Tlacsin Fm

Period:

Ordovician, Silurian

Age Interval:

late Hirnantian-earliest Silurian

Province:
Ghadames Basin

Type Locality and Naming

Synonym:

References: Bora and Dubey, 2015.

Lithology and Thickness

The Bir Tlacsin Fm. is made up of sandstones that grade laterally into the shales of its equivalent in the Murzuq Basin (see Fig. 2 of Bora and Dubey, 2015).

Lithology Pattern:

Clayey sandstone

Relationships and Distribution

Lower contact

It conformably overlies the Mamuniyat Fm.

Upper contact

It is conformably overlain by the Tanezzuft Fm.

Regional extent

It extends in local pockets throughout the Ghadames Basin.

GeoJSON

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Fossils

Age

Local infilling of incised channels created during the Hirnantian glaciation and covered by the early Silurian transgressive shales. Age span within the latest-Hirnantian-early Rhuddanian.

Age Span:

Beginning stage:

Hirnantian

Fraction up in beginning stage:

0.7

Beginning date (Ma):

443.71

Ending stage:

Rhuddanian

Fraction up in the ending stage:

0.15

Ending date (Ma):

442.68

Depositional setting

Local infilling of incised channels created during the Hirnantian glaciation

Depositional pattern:

Additional Information

Compiler:

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.