Jardinah Formation

Jardinah Fm

Period:

Neogene

Age Interval:

Burdigalian

Province:
Cyrenaica Basin

Type Locality and Naming

“The Jardinah Fm is an Early Miocene lithostratigraphic unit introduced by stratigraphers to formally redefine and isolate the basal, older portion of what was traditionally lumped into the broader Benghazi Fm. Because the traditional Benghazi Fm spanned a wide time interval with varying open-marine to restricted facies, regional geologists proposed "Jardinah Formation" to clearly delineate the distinct, open-shelf Early Miocene transgressive sequence from the younger Middle Miocene rocks.” (from Google Gemini overview)

Synonym:

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

Lithology and Thickness

Predominantly bioclastic packstones, wackestones, calcarenites, and rich fossiliferous limestone beds.

Lithology Pattern:

Limestone

Relationships and Distribution

Lower contact

Unconformable (upper Aquitanian is absent) onto the Al Faidiyah Fm according to Shaltami et al. (2020).

Upper contact

Unconformably (the upper Burdigalian is absent) overlain by the Benghazi Fm of the Ar Rajmah Gr according to Shaltami et al. (2020).

Regional extent

GeoJSON

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Fossils

It was deposited in a shallow, open-marine platform setting supporting diverse marine life, notably red algae (rhodoliths), echinoids, bryozoans, and benthic foraminifera.

Age

Burdigalian according to Shaltami et al. (2020). [For graphic purposes, the extent of the upper and lower unconformities, which are equivalent to nearly the same time span of the known preserved deposits, have been omitted here, but is included in the stratigraphic column.]

Age Span:

Beginning stage:

Burdigalian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

20.45

Ending stage:

Burdigalian

Fraction up in the ending stage:

1.0

Ending date (Ma):

15.99

Depositional setting

Represents a major Early Miocene marine transgression across the Cyrenaica Platform.

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.