Wadi Qattara Formation

Wadi Qattara Fm

Period:

Neogene

Age Interval:

Messinian

Province:
Cyrenaica Basin

Type Locality and Naming

Used here for the cluster of Messinian-age formations of Shaltai et al. (2020) of the Al Jaghbub Fm (basal Messinian), and a middle and upper Messinian trio of Wadi Al Qattarah Fm, Bu Mariam Fm and Al Abyar Fm. All are separated by unconformities in their chart. But Google Gemini overview lumps all of these under a broader definition of the Wadi Al Qattarah Fm.

Synonym:

References: Shaltami, O.R., et al. (2020), and Google Gemina (Aug’26)

Lithology and Thickness

Highly evaporitic sequence characterized by thick, irregular gypsum bodies, siliceous oolitic limestones, and interbedded gypsiferous mudstones. The Messinian set represents a shallowing-upward, restricted marine phase. It is dominated by cross-bedded oolitic grainstones, microbialites (stromatolites and thrombolites), green shales, and thick bedded evaporites (gypsum and anhydrite).

Lithology Pattern:

Evaporite

Relationships and Distribution

Lower contact

Unconformable onto the Benghazi Fm suite of reef-type limestones of the Ar Rajmah Gr.

Upper contact

Unconformably overlain by the Umm Al Gharaniq Fm of the Al Hishah Gr according to Shaltami et al. (2020).

Regional extent

GeoJSON

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Fossils

Age

Messinian. For graphic purposes, the unconformities between the sub-units are not included.

Age Span:

Beginning stage:

Messinian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

7.25

Ending stage:

Messinian

Fraction up in the ending stage:

1.0

Ending date (Ma):

5.34

Depositional setting

The Messinian set represents a shallowing-upward, restricted marine phase. The upper gypsum and microbial beds mark the onset of restricted marine conditions linked to the drawdown of the Mediterranean Sea near the end of the Miocene.

Depositional pattern:

Additional Information

Compiler:

Shaltami, O.R., et al. (2020). Petroleum system of the Cyrenaica Basin – A review. In: 1^st International Symposium on Geosciences (ISG2020), 21th March 2020, Proceeding Book: published by BR Petrobras. P. 64-71.

Tawadros, E.E. (2011). Geology of North Africa. CRC Press (Taylor & Francis Group), 931 pp.

Google Gemini (Aug 2026) – assembled synthesis of Cyrenaica Basin units from various web-accessible publications.

El Oshebi, F.M., Fares, F.F. (2026). Stratigraphy, facies, and depositional environments of the Eocene sequence in the Ras Al Hilal area, Cyrenaica, Libya. Arabian Jour. Geosciences, 19:79. https://doi.org/10.1007/s12517-026-12488-2.

El-Hawat, A.S., Abdulsamad, E.O. (2004) Geology and Archeology of Cyrenaica, Northeastern Libya. Field trip guide B01, 32^nd International Geological Congress. 36 pp.