Chicla Formation

Chicla Fm

Period:

Cretaceous

Age Interval:

Berriasian – Barremian.

Province:
Ghadames Basin

Type Locality and Naming

Synonym: Equivalent to Cabao Fm (clayey dolomite of Berriasian-Hauterivian) plus overlying Continental Intercalaire Fm (sandstone of Barremian) of the Triassic Basin succession (Klett, 2000)

References: Bora and Dubey, 2015

Lithology and Thickness

The Chicla Fm. is mainly sandstones (Bora and Dubey, 2015) to sandy limestone (Klett, 2000)

Lithology Pattern:

Sandstone

Relationships and Distribution

Lower contact

It unconformably (Base Cretaceous unconformity) overlies the equivalent of the Touratine Gr– see Fig. 2 of Bora and Dubey, 2015). However, this “Touratine Gr” is the Serie de Taouratine of the Illizi Basin, whereas USGS-Klett have the Tauratine ending in mid-Cretaceous. Therefore, the underlying unit, based on the general Triassic Basin stratigraphy, is the Shakshuk Fm (Soesciuch Fm) as in the Triassic Basin regional stratigraphy of Oued Mya Basin, etc..

Upper contact

It is unconformably overlain by the Nefusa Fm. (Austrian unconformity – see Fig. 2 of Bora and Dubey, 2015).

Regional extent

It extends throughout the Ghadames Basin.

GeoJSON

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Fossils

Age

Age Span:

Beginning stage:

Berriasian

Fraction up in beginning stage:

0.00

Beginning date (Ma):

143.10

Ending stage:

Barremian

Fraction up in the ending stage:

1.0

Ending date (Ma):

121.40

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:

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.