The regional stratigraphy is continuous across North Africa and have been controlled by the tectonic history of individual basins. Deformational events in the region, most of them minor, are recorded by unconformities reflecting basin tilting, uplift, and erosion of intracratonic structural axes at various throughout the Phanerozoic. The main old deformational events occured in the Precambrium to Early Cambrium, Late Silurian to Early Devonian, Carboniferous to Permian.
Throughout most of Paleozoic, North Africa was a single depositional basin on the northern shelf of the African craton. The basin generally deepened northward where deposition and marine influence were greater. In the Late Silurian and Early Devonian, Laurasia separated from Gondwana resulting in minor deformation, uplift, and lokal erosion. Many of the basins and uplifts preserved today were initially developed during this event from ealier structures. Later, in the Middle to Late Devonian, the initial collision of Laurasia and Gondwana began resulting in erosion and further modification of preexisting structures. The Hercynian orogeny (Carboniferous to Permian) marks the collision between Laurasia and Gondwana and caused regional uplift, folding, and erosion. Paleozoic basins that were delineated by earlier tectonic events were modified, resulting in the development of several intracratonic sag and foreland basins.
Several transgressive-regressive cycles occurred throughout the Paleozoic. Two major flooding events, one in the Silurian and other in the Carboniferous. Many of the prograding fluvial, esturine, deltaic, and shallow marine sands that were deposited during these cycles.

During the Paleozoic, most of the area between northwestern Sudan, southeastern Libya and southwestern Egypt was a stable part of the African craton without much structural differentiation. There was, however, a zone of strong subsidence along the eastern edge of the Kufra basin, the Howar-Uweinat-Uplift. This area became subsidence during the Early Paleozoic and continued until to the Devonian age. The Howar-Uweinat Uplift forms the eastern border of the deep Kufra Basin in Libya. The meaning of the Howar-Uweinat-Uplift documents itself through the enormous difference of the Basement base between Uplift and Kufra Basin of up to >3000 m. At the eastern edge of the Uplift is the difference with <500 m essentially lesser. It is evident, that in maximum of two times probably parts on this structure was uplifted and sediments were eroded. The last significant ascent happened by the Bretonian event of the Upper Devonian age.
The Kufra Basin in southeast Libya forms an elongate depression oriented northeast-southwest, with an aerial extent of about 400,000 km2. The Kufra Basin began in the Early Paleozoic. By marine transgression during the Lower Silurian and Upper Carboniferous, which intercalated the far-reaching continental sedimentation, thick, vastly differentiated predominantly Paleozoic sediments are found here. The basin fill attains a maximum thickness of 3000 m and comprises a sequence of Paleozoic sediments unconformably overlain by Mesozoic strata and has remained land since the end of Paleozoic times. The centre oft he basin is sand covered and except for a few small isolated hills of Cretaceous Nubian sandstone outcrops are limited to the southeast and southwest of the Kufra oasis. The base of the Paleozoic succession is exposed only in the north, southeast and southwest where it rests unconformably on Precambrian basement. See also International Conference, Cairo 2007
Another basin developed northeast of the Howar-Uweinat-Uplift in Egypt. This Dakhla Basin is filled with Mesozoic strata . The Dakhla region was probably in the Paleozoic period mostly a highland. A separation of the Kufra Basin from the Dakhla Basin is evident, because the Dakhla Basin is a younger depression filled predominantly with sediments of the Cretaceous age of maximal 3000 meters in thickness.
The origin of an other Uplift (Uweinat-Bir Safsaf-Aswan-Uplift) is not clear. The whole area from directly east of Djebel Uweinat to Aswan formed a regional high from which Paleozoic and older Mesozoic strata were generally not present, or they were eroded and then transported to south (Lakia Formation in Sudan).
 

Probable structural - geological development

 

The area between Djebel Uweinat and Gilf Kebir (incl. Abu-Ras Plateau, Jabal Asba, Djebel Kamil, Djebel Kissu etc.) is an area on the Howar-Uweinat-Uplift. The Basement reaches an evenly altitude to the earth's surface. The first uplifting of the area resulted probably already in the Early Paleozoic (late Silurian). The second uplifting resulted probably in the Upper Devonian age (Bretonian event). The third uplifting resulted probably in the Carboniferous age (Sudetian event).
This high structure was since the first uplift then more a area of denudation and fewer a area of sedimentation. The whole sedimentary block over the Basement reaches both in the Gilf Kebir as well as in the Djebel Uweinat a maximum thickness of 400 m. The Basement outcrop between Uweinat and Gilf Kebir is approximately of + 600 m NN. The Gilf Kebir block (incl. Abu-Ras Plateau) has a high of +1000 m NN. The hardened mountain ridge of the Abu Hassanein plateau of the Djebel Uweinat (+1800 m NN) is built by a tertiary magmatic intrusion and a followed uplift of the sedimentary block of Silurian (?) and Devonian strata. On top of the mountain ridge is placed a striking crater with a basaltic bottom. The Carboniferous strata at the Uweinat and surrounding are a near-shore facies of a transgression from the southern Kufra basin. The strata overlain unconformably the northeastern to southeastern foothills of the already uplifted mountain range of the Djebel Uweinat. The sediments of the Lower Carboniferous age in the Abu-Ras plateau (northern Gilf Kebir) and Jabal Asba, specially from the Wadi Abdel Malik, are the result of an advance of the Carboniferous transgression over the eroded side of the plateau, from the northern Kufra basin coming.
In the uplifted area, between Gilf Kebir and Djebel Uweinat, deposits of the Lower Cretaceous occure as remains. Specially sediments nearby the Aqaba passage and in the Wadi Wassa represent the most extensive expansion of early sediments of Cretaceous age, from the Abu Ballas area coming. More complete Cretaceous deposits are found in edge-position of the uplift southwest of Abu Ballas (Djebel Kamil and surroundig).

1. Paleozoic Sedimentation
    Djebel Uweinat and surrounding
    Abu-Ras Plateau (= northern Gilf Kebir plateau)
    Kemal-el-Din Plateau (= southern Gilf Kebir plateau)
    Jabal Asba (Libya)
    Jabal Zalmah/Dalma (Libya)
2. Early Cretaceous Sedimentation
    Surrounding of Kemal-el-Din Plateau (= southern Gilf Kebir plateau)
    Djebel Kamil and surrounding
 

1. Paleozoic Sedimentation
    (in sense KLITZSCH, E. & SCHANDELMEIER, H., in Geology of Egypt, 1990)

The best exposures of Paleozoic strata are to be seen in the Gilf Kebir - Djebel Uweinat area:  At the southern slope of the Abu-Ras Plateau (meant is northern part of  Gilf Kebir), the Um Ras area (near the Libyan border), Wadi Talh (within the Abu-Ras Plateau) and its side wadis and, further south, at the northeastem, eastern and southeastern edge of Djebel Uweinat including Karkur Talh, Wadi Wahesh and Karkur Murr.

Ordovician Sedimentation
The only place where Paleozoic strata older than Silurian is known in the area investigated is Gebel Uweinat. SEILACHER identified Cruziana cf. rouaulti LEBESCONTE which was found by MONOD on sandstone just above basement around 21°58'N and 25°08’E in Northern Sudan. This trilobite track indicates an Ear1y Ordovician age. It is from nearshore marine sandstone which contains abundant Skolithos sp. in some beds. This formation is called Karkur Talh Formation. It is exposed at both sides of Karkur Talh in the eastern part of Gebel Uweinat. Several ten meters of interbedded fluvial sandstone and conglomeratic sandstone are intercalated with highly bioturbated marine sandstone. The formation unconformably overlies Precambrian metamorphics and is unconformably overlain by marine and fluvial sandstone of Silurian (?) age (Umm Ras Formation).
Remark: This formation agrees with the Umm Ras Formation. A fossil trace (Cruziana cf. rouaulti LEBESCONTE) is no useful marks for a separation.

Silurian (?) Sedimentation

Along the southern foreland areas of the Abu-Ras Plateau, probably Silurian (?) strata can be studied. There, fine to medium and partly coarse-grained white sandstone of fluvial and deltaic origin is interbedded with nearshore marine sandstone, beach sand and silty shale to clayey silt-stone. Several beds are intensively burrowed by trace fossils (Scolithos, Harlania/Arthrophycus, Cruziana). This so called  Umm Ras Formation reaches above the Precambrian Basement a maximum thickness of approximately 100 meters. It builds the lower parts of the Abu-Ras Plateau and Gilf Kebir Plateau (including Aqaba Passage).
In the entire Djebel Uweinat shallow marine to fluvial sandstone forms the lower sandstone unit directly overlying the Precambrian Basement (for example to seen at Karkur Talh). These strata are, in parts, highly burrowed by trace fossils (Scolithos , Harlania/Arthrophycus, Cruziana). These Sediments are very similar to strata found near the Umm Ras Passage along the Libyan border and strata found southeast of Djebel Kissu. The thickness of this Silurian (?) strata of Djebel Uweinat is less than 100 m.
At the outliers and small plateaus, directly east of Djebel Uweinat along the Sudanese border, the basal part of the strata consists of  Silurian strata, as around Karkur Talh.
The massive sandstone outcrops at the edges of the granite-domes of the Jabal Arkenu and Jabal Babein are likewise probably of Ordovician age, in sense to BELLINI & MASSA (1980).

Remark: The series of this sedimentary units were named by BELLINI & MASSA  (The Geology of Libya) as Memouniat Formation and classified as Ordovician. This contrast must be clarified. In any case fossil traces are no useful marks for a dating. Here a suggestion for the correlation of both geological sequences. See also Jabal Asba.
 

Devonian Sedimentation
Devonian strata are exposed on surface in the Jabal Asba (Libya), along the western and southwestern edge of the Abu-Ras Plateau near the Libyan border,  north of the Umm Ras Passage toward Wadi Abdel Malik, at the northern Gilf Kebir Plateau, at the northern part of Djebel Uweinat etc. Unfortunately, no paleontological proof has been found until now within southwest Egypt. The stratigraphical interpretation is based on the position of these sediments between underlain strata of proven Silurian (?) age and  overlain strata of proven Carboniferous age. This sandstone is very similar in appearance to the Tadrart Sandstone of Libya.
The Devonian sediments consists of mainly tabular cross-bedded fine-to coarse-grained sandstone, partly slightly conglomeratic, frequently with convolute bedding. These are also present in lesser thicknesses southeast of Djebel Kissu in Sudan.

Carboniferous Sedimentation
The Wadi Malik Formation more or less conformably overlies the Devonian beds in the middle part of the southwestern and western Abu-Ras Escarpment. It is, however, best exposed all along the Wadi Abdel Malik and its side wadis (Wadi Talh) which reach from the southern and southwestern part of this 60 x 120 km large plateau towards its relatively flat northern end. The approximately 100  m thick Wadi Malik Formation consists of marine sandstone, siltstone and shale interbedded with fluvial, deltaic and tidal sandstone. In marine beds, brachiopods (Camerotoechia sp.), trace fossils (like tracks of tribolites) and starfish (Asteriacites) or burrows like Bifungitis fezzanensis DESIO are frequent. Other forms (Scolicia, Neonereites, Zoophycus, Phycosiphon) provide no time signature, while they may be used as indicating marine conditions. Several non-marine beds contain frequent plant remains including many different plant remains of Visean age (for example Triphyllopteris, Eremopteris, Rhodea, Rhacopteris) .
In north Wadi Abdel Malik, the Wadi Malik Formation underlies unconformably a 30 to 60 m thick bed of an chaotic sediment, consisting of clay, sand, gravel, blocks of older strata up to house size. Southward, in the middle and southern parts of Wadi Malik and its side wadis, these strata are replaced by fluvial sandstone, conglomerate and sandstone with isolated blocks of older strata (erratic boulders). The thickness of this fluvio-glacial unit is several tens of meters. It is overlain by cross-bedded and parallel-bedded sandstone containing plants of Stephanian age in the central parts of the Abu-Ras Plateau, for example Cordaites sp., was found in sandstone directly overlying the fluvio-glacial North Wadi Malik Formation.
Both in the southeastern part of Djebel Uweinat at Karkur Murr and in the northeast at Karkur Talh, and also directly east of the mountain area, Carboniferous strata are present in varying thickness and facies. The lower 50 to 120 m of the Carboniferous section are mainly made up of sandstone, siltstone and some shale deposited in shallow marine, coastal floodplain or fluvial environment. Parts of the strata are intensively burrowed and brachiopods as well as plant remains of Early Carboniferous age are common. At Karkur Murr these strata rest directly on Precambrian rocks, while at Karkur Talh, as well as east of Djebel Uweinat, they overlie older Paleozoic strata. In most locations, they more or less conformably overlie the Devonian Tadrart Sandstone Formation.

Above these partly marine strata, a unit of very heterogeneous Sediments follows. It is made up of fluvial sandstone which is interbedded with a very regularly-laminated siltstone (similar to varve Sediments) in some locations, for example the section at Karkur Murr; the base of this unit is made up of several meters of a chaotic sediment similar to Tillite.  At Karkur Talh and southeast of Djebel Uweinat in Sudan, the varve-type siltstone dominates the whole formation. It occupies the same stratigraphic position of the Tillite and the fluvio-glacial sandstone of the northern Wadi Malik and is, therefore, called the North Wadi Malik Formation. Previously, the varve-type sediments were called Lake Beds Formation.

Remark: Varve-like siltstones of the northern Sudan the author found also at the northern plateau of the Djebel Uweinat and at the western edge of the southern Gilf Kebir plateau as valley-filling.

The Silurian shallow marine to fluvial sandstones forms the lower unit directly overlying the Precambrian Basement in the Djebel Uweinat. These strata are, in parts, highly burrowed by trace fossils (Scolithos, Harlania/Arthrophycus, Cruziana). They exposed on surface at the eastern part of Djebel Uweinat as a markedly silty sandstone layer.

In 2009 Andras Zboray found on the northern part of the plateau the Silurian trace fossils Arthrophycus again. The find-layer is the same as in the eastern part of the Uweinat.

    
Ichnofossils from southern Karkur Thal (3) and northern plateau (1). Photos: Andras Zboray, 2008 and 2009


Ichnofossils from the southern (2) and upper end of western Karkur Thal (1). Photos: The autor, 2006

 
Strata very similar to the Umm Ras Formation also overlie the basement in Northern Sudan south and east of Gebel Kissu. Southward and eastward the continental influence of this sediment increases. Nevertheless, Harlania harlani DESIO and Cruziana acacensis SEILACHER are found 50 kilometers SSE of Gebel Kissu, and Skolithos sp. within the same formation approximately 100 kilometers east of Gebel Kissu.

Devonian strata are exposed on surface at the northern part of Djebel Uweinat. Unfortunately, no paleontological proof has been found until now within southwest Egypt. This sandstone is very similar in appearance to the Tadrart Sandstone of Libya. The Devonian sediments consists of mainly tabular cross-bedded fine-to coarse-grained sandstone, partly slightly conglomeratic, frequently with convolute bedding.

The hardened mountain ridge of the Abu Hassanein plateau of the Djebel Uweinat (+1800 m NN) is built by a tertiary magmatic intrusion and a followed uplift of the sedimentary block with Silurian and Devonian strata. On top of the mountain ridge is placed a striking crater with a basaltic bottom !
 

The presence of Lower Carboniferous strata has been known for a long time from Karkur Murr and Karkur Talh at the eastern side of Djebel Uweinat. It was already known, that the so-named Karkur Murr/Wadi Waddan Formation  (now Wadi Malik Formation in sense KLITZSCH) consist of sandy shales and include often numerous well-preserved plant remains.

The Carboniferous strata of this Wadi Malik Formation are present in varying thickness and facies. It is normally several 10 meters thick and it consists of  crossbedded to flaserbedded sandstone, siltstone and some shale deposited in shallow marine, coastal floodplain or fluvial environment. Parts of the strata are intensively burrowed and brachiopods as well as plant remains of Lower Carboniferous age are common. At Karkur Murr these strata rest directly on methamorphic Precambrian rocks, while at Karkur Talh, as well as east of Djebel Uweinat, they overlie older Paleozoic strata.
The Carboniferous strata at the Uweinat and surrounding areas are a near-shore facies of a transgression from the southern Kufra basin. The strata overlain  unconformably the northeastern to southeastern  foothills of the already uplifted mountain range the Uweinat. Remains of strata from the Carboniferous transgression also were found extensive at the northern Clayton Craters and approximately 100 kilometers southeast of Djebel Kissu.

On the eastern side of the Uweinat massif, at Karkur Murr, it is possible to see a good exposure of the contact between the metamorphic basement and the lowermost Carboniferous. The basement is formed of schists and gneisses, reddish-grey, folded, with numerous quartz veins; it is unconformably overlain by a thin bed of sandstone and approximately 10 m of rhyolite. These volcanics are followed by 15 m of shale and sandstone interbeddings and, subsequently, approximately 35 m of cross-bedded sandstones with rare shale interbeddings. The lower sandy shales often yield numerous, well-preserved plant remains.

At Djebel Uweinat, (Karkur Murr and Karkur Talh), the Wadi Malik Formation contains the following flora of Lower Carboniferous age:
Cyclostigma ungeri JONGMANS
Lepidodendropsis aff. rhombiformis DE ROUVRE
Lepidodendropsis cf. vandergrachti JONGMANS
Precyclostigma tadrartense LEJAL-NICOL

Directly east and southeast of Djebel Uweinat as well as approximately 100 kilometers east of Djebel Kissu, both in northwestern Sudan, the following flora was found:
Triphyllopteris cf. rhombifolia DABER.
Lepidodendron veltheimi STERNBERG
Lepidodendropsis vandergrachti JONGMANS
Prelepidodendron aff. lepidodendropsis LEJAL
Lepidosigillaria intermedia LEJAL
Archaeosigillaria vanuxemi KIDSTON
Precyclostigma sp.

Without exact statements to the place of discovery in the Djebel Uweinat and surrounding are finds mentioned of
Rhodea aff. lotzensis STOCKMANS
Cordaites cf. angulostriatus GRAND'EURY
Eskdalia africana LEJAL-NICOL
Eskdalia malikense LEJAL-NICOL
Eremopteris elegans E.L.
Ursodendron aegyptiacum LEJAL-NICOL
Archaeocalamites sp.

In recent years, and especially in 2008 and 2009 by Andras Zboray, were found fossil plants on the northern part of the Uweinat plateau. The plant-remains of the types "Lepidodendron" and "Sigillaria" are usually not well preserved. The barely layered deposits have a fine-grained or coarse-grained facies. The finds were deposited on intra-Devonian level. It is likely that this deposits are terrestrial, this means, products of the intra-erosion of the Devonian mountains. This facies differs from the shallow-marine or coastal facies on the eastern side of the Uweinat (e.g. Karkur Murr). The plant-remains are preserved almost in situ. In contrast, the plant-remains in shallow-marine deposits are allochthon of origin at the eastern part of the Uweinat.

         
In the foreground terrestrial Carboniferous layers with plant-remains

Along the southern foreland areas of the Abu-Ras Plateau (including the Aqaba Passage) and the Umm Ras Passage, Paleozoic strata can be studied at many places. The best exposures and a very thick section are at the Umm Ras passage, directly south of the Abu-Ras Plateau near the Egyptian-Libyan border. The Silurian Umm Ras Formation reaches a thickness of approximately 100 m between the Umm Ras area and the southwestern slope of the Abu-Ras Plateau. It consists mainly of fluvial and deltaic white sandstone, intercalated with interbeds of shallow marine siltstone, some shale and burrowed sandstone. These beds contain Harlania harlani DESIO, Cruziana cf. acacensis SEILACHER, Scolithos sp. and other trace fossils at several levels. This Umm Ras Formation reaches as far east as the Aqaba Passage and  Gilf Kebir Plateau.
At the type locality, the Umm Ras Formation directly overlies Precambrian basement. South of the Umm Ras passage, the trilobite tracks of Silurian age occur only some meters above basement. At the Umm Ras passage they occur also in the upper part of the section. The facies of this formation is very similar to the Akakus Sandstone in Libya.

Between the Umm Ras Formation and the Wadi Malik Formation of Carboniferous age, approximately 300 m (?) of fluvial sandstone similar to the Devonian Tadrart Sandstone, are exposed at the escarpments of the Abu-Ras Plateau and Gilf Kebir Plateau. At the Aqaba Passage the Devonian strata are truncated by the Gilf Kebir Formation of Early Cretaceous age. Trace fossils or plant remains were not found up to now.

At the Wadi Abdel Malik respectively at the western foreland of the Abu-Ras Plateau (Wadi Talh), shallow marine sandstone, siltstone and shale prevail, containing - apart from plants - brachiopodes, lamellibranchiates and different ichnofossils. These strata reach more than 100 meters of thickness in the Abu-Ras area and they are called Wadi Malik Formation (KLITZSCH 1979). Here they are overlain by a tillite of up to several 10 meters in thickness. Southward in the southern parts of Wadi Abdel Malik area, the stratigraphical position of the tillite is taken by crossbedded sandstone containing irregular large blocks. This sandstone seems to be of fluvial-glacial origin.

The sediments of the Wadi Malik Formation lie over an eroded base of the Devonian Tadrart sandstone unconformably. They were deposited during a transgressive expansion of the Kufra basin in the Lower Carboniferous age from the northwestern direction.

A rich flora was discovered in the Wadi Abdel Malik/Wadi Talh type area, including: Archaeosigillaria minuta, Lepidodendropsis cf. sinaica, Lepidosigillaria intermedia, Prelepidodendron lepidodendroides, P. rhomboidale, Rhacopteris ovata, Triphyllopteris gothani. This flora proves a Tournaisian to Visean age.

At Wadi Abdel Malik/Wadi Talh, were found this flora several meters below intercalations containing remains of different brachiopods, for example Camerotoechia sp. as well as abundant marine ichnofossils (SEILACHER, 1983) including Asteriacites gugelhupf, Bifungites fezzanensis, Spirophyton sp., Cruziana sp. and many others.

The upper part of Carboniferous strata, which is mainly made up of diamictites, occurs in three different facies, which interfinger and which all rest unconformably upon the Wadi Malik Formation. At central parts of Wadi Abdel Malik, the formation rests above an erosional contact on sandstone of Lower Carboniferous age. The uppermost parts of the underlying strata contain plant remains like Triphyllopteris gothani. The upper part of the formation, which is here approximately 50-55 m thick, is overlain by a thin conglomerate followed by sandstone, containing among others Cordaites angulostriatus, which, according to LEJAL-NICOL (1987) indicates Stephanian age. Moreover, the upper part of the northern Wadi Malik Formation - directly below the conglomerate - contains Rhodea lontzenensis, which indicates Namurian age for the glacial formation.

Carboniferous strata in the Wadi Talh	Karma pass
Carboniferous strata in the western part of Wadi Abdel Malik (Wadi Talh) in the foreground marine shales Carboniferous strata in the northern part of Wadi Abdel Malik Hill with the marine shales and bioturbation	Section through Wadi Malik Formation from the Wadi Abdel Malik area  Source: KLITZSCH & WYCISK, 1987 Marine shales of the Carboniferous age Bioturbation
Carboniferous shales and siltstones on top	Plant-rich layers in the Wadi Talh

The whole Gilf Kebir plateau is built by Paleozoic rocks (Devonian strata and probably a reduced Silurian base).  The Aqaba passage is an eroded valley between northern Abu-Ras Plateau and southern Kemal-el-Din Plateau.

2. Early Cretaceous Sedimentation
    (in sense KLITZSCH, E. & SCHANDELMEIER, H., in Geology of Egypt, 1990)

Early Cretaceous strata (possibly also late Jurassic age) were deposited at the Kemal-el-Din Plateau (meant is the southern foreland of the Aqaba passage and  the Wadi Wassa), along the northern edge of the Abu-Ras Plateau and at the Djebel Kamil as well as surrounding. Nearby the Aqaba passage this unit overlies Precambrian basement, and on the Abu-Ras Plateau it unconformably overlies Paleozoic beds. The so-named Gilf Kebir Formation covers also areas southeastwards toward Djebel Kamil.
In the upper part of the southern Abu-Ras Plateau and on isolated hills on the plateau in this extensive landscape, the Carboniferous strata underlie unconformably the Gilf Kebir Formation. These strata consist of fluviatile, deltaic and partly near-shore sandstones.
At the eastern edge of Gilf Kebir toward the Abu Ballas area, the Gilf Kebir Formation is overlain by Nubian strata of Lower Cretaceous age (incl. marine Abu Ballas Formation). Within layers at the Aqaba Passage as well as at the western end of Wadi Wassa (Wadi Firaq) in the south are several horizons rich in flora. There is however unfortunately no exact statements to the places of the discovery. Fine-grained sandstone and siltstone locally contain an abundant flora of ferns and other plants of the Early Cretaceous age (among Cladeophlebis oblonga HALLE, Phlebopteris polypodoides BRONGNIAERT and Weichselia reticulata STOCKES & WEBB. More or less the same facies also characterizes the Early Cretaceous Gilf Kebir Formation on top along the northern edge of the Abu-Ras Plateau, north and northeast of Wadi Abdel Malik. The lower part of Djebel Kamil and strata in southern surrounding are similar characterized by lower Cretaceous flora (some meters above basement).

Fossil flora separated in the surrounding of southern Kemal-el-Din Plateau  and at the northern edge of the Abu-Ras Plateau indicate the presence of Early Cretateous strata. Pteridophylla and Gymnosperms are found:

At the southern foothills of Kemal-el-Din Plateau  (Wadi Wassa) a similar flora is present with:
Phlebopteris muensteri SCHENCK   ?
Podozamites sp.

Remark: All not easily to determined plant remains probable on Weichselia reticulata based. That could be a mistake. In the Wadi Halfa (Sudan) was recently found a similar form. It is a very similar Paleoweichselia aff. defrancei BRONGNIART from the Upper Carboniferous (Westphalian). The reticulate venation is imperfectly developed.

At the eastern part of the Howar-Uweinat-Uplift, in the Gebel Kamil area sequences of fluvial sandstones and interbedded nearshore sediments with channel-fill fades overlie the Precambrian basement with a total thickness of maximal 100 m meters. They are of Cretaceous age.
The lower part is named “Gilf Kebir Formation” (equivalent of Six Hills Formation ? or younger ). Sedimentation starts with the upper part of the Gilf Kebir Formation, which consists of intercalations of fluvial braided and minor tidal-channel deposits, overlaying a thin basal conglomerate.
The section contains fluvial, medium to coarse-grained sandstones with single conglomeratic layers at the scoured base of the sequence. Small-scale tabular cross-bedding is the main facies in these cycles, trough cross-sets occur infrequently.
The fluvial deposits are interbedded by nearshore sediments ranging from 2-6 meters in thickness. This facies consists of grey medium to fine-grained sandstones with silt and shale intercalations. Wavy, flaser-and-lenticular bedding prevail in the lower part of the coarsening-upward sequence. This facies in particular is overlain by massive or irregular horizontally laminated sandstones, containing shale intraclasts, scattered quartz granules and isolated vertical burrow tubes. Burrows of Spongeliomorpha up to 15 cm in diameter occur in an intensely bioturbated sandstone.

The upper shore face deposition is characterized by medium to coarse-grained well sorted sandstones, with laminated layers, low angle and trough cross-beds. Vertical burrow tubes probably made by crabs are present throughout the facies. Press structures similar to “Lebensspuren” of sea urchins occur in the section.

At Djebel Kamil between 30 and 55 meters above Basement the following flora is found:
Cladophlebis aff. oblonga HALLE
Cladophlebis aff. patagonica FRENGUELLI
Phlebopteris aff. muensteri SCHENCK
Podozamites sp.

Twenty-two kilometers south of Djebel Kamil the following flora is found approximately 20 meters above Basement:
Neocalamites sp.
Weichselia reticulata STOCKS & WEBB

Sources:

KLITZSCH, E. & LEJAL-NICOL, A. (1984): Flora and fauna from strata in southern Egypt and northern Sudan (Nubia and surrounding areas).
Berliner geowiss. Abh., (A) 50, p. 47-79.
KLITZSCH, E. (1984): Northwestern Sudan and bordering areas: Geological development since Cambrian time.
Berliner geowiss. Abh., (A) 50, p. 23-45.
WYCISK, P. (1984): Depositional Environments of Mesozoic strata from northwestern Sudan.
Berliner geowiss. Abh., (A) 50, p. 81-97.
KLITZSCH, E. & WYCISK, P. (1987): Geology of sedimentary basins of northern Sudan and bordering areas.
Berliner geowiss. Abh., (A) 75.1, p. 97-136.
LEJAL-NICOL, A. (1987): Flores nouvelles du Paleozoique et du Mesozoique d’Egypte et du Soudan septentrional.
Berliner geowiss. Abh., (A) 75.1, p. 151-248.
 

"Geology of Egypt"
A. A. Balkema, Rotterdam, 1990
 

"The Geology of Libya", Volume I
M. J. Salem & M. T. Busrewil, Academic Press, 1980