Ar Rajmah Gr

According to Shaltami et al. (2020), this group consists of an upward succession of a Jardinah Fm (lower Burdigalian), Benghazi Fm (Langhian-lowermost Serravalian), Al Sceleidima Fm (upper Serravallian), Msus Fm (middle Tortonian), 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. [Most of those formations were indicated on stratigraphic charts in other publications consulted during preparation of this lexicon.] The overview by Google Gemini splits into just two main formations – a lower Benghazi Fm and an upper Wadi Al Qattarah Fm – which is used here for simplicity (and lack of other details), but with addition of the basal Jardinah Fm.

Synonym: Ar Rajmah Fm

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

Wadi Al Qattarah Fm (Upper; Messinian age): Evaporite-rich. 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).

Benghazi Fm (Lower; Langhian-Tortonian age): Reef-limestone-type rich. Deposited during a Middle Miocene marine transgression. It consists of open-marine skeletal packstones, coral-reef boundstones, and fossiliferous rhodolith (red algae) beds.

Jardinah Fm (basal; Burdigalian age): Predominantly bioclastic packstones, wackestones, calcarenites, and rich fossiliferous limestone beds. Represents a major Early Miocene marine transgression across the Cyrenaica Platform.

Extensive outcrops of the group (especially south and east of Benghazi) serve as key field analogs for complex ooid-grainstone and microbial carbonate hydrocarbon reservoirs across the North African subsurface