Geomorphology of Dakhla Depression
53
According to the above mentioned study this pediplain reaches a huge stretch
(70,000 km
2 ) and is dissected by many E-W faults giving rise to scarps of low
altitudes, 40–50 m above the surface of the desert, isolated hills, ridges and many
small local depressions. The altitude of this pediplain ranges from 100 m amsl at its
eastern side near Kharga scarp to 500 m amsl near the twin hills of Abu Ballas at the
edge of the Sand Sea (see for more details Issawi et al. 2009).
Dakhla depression is also geophysically connected with the wider region. In
their research about the Nubian Sandstone Aquifer System (recharge, depletion, and
connectivity) Mohamed et al. (2016) studied the other sub-basins: Dakhla, Northern
Sudan Platform, and Kufra.
The importance of Dakhla exceeds its regional geomorphology to the global
one, especially with respect to paleogeography. According to Moawad et al. (2008)
Mawhoob area revealed a prominent accumulation of vertebral bones that delineate outlines of huge vertebral animals (more than 10 m in length) indicating that
these skeletals were associated with large vertebrates that lived during the Mesozoic
period. The previously mentioned study concluded that these animals are reaching
its climax through the Upper Cretaceous and extinct by the close of the Cretaceous
time.
The importance of this discovery lies in its standing mostly upon two facts; the
first is the intact relationship of these bones. The second is the stratigraphic position
where these bones were accumulated. The bones herein precisely mark the (K/T)
boundary (see for details Moawad et al. 2008).
These results were affirmed by recent findings of skeletons of dinosaurs in Teneida
area (Eastern Dakhla), which becomes world widely known as Mansourasaurus: a
Late Cretaceous dinosaur dispersal between Europe and Africa (see for more details
Sallam et al. 2015).
3 Principal Geomorphological Units
3.1 Plateau and Escarpment
The tabular landscape of the Western Desert of Egypt is known in the previous literature as “the Libyan plateau” where the most prominent geomorphological landmark
in the study area is a transverse scarp wall generally runs ESE-WNE for about 300 km
(see Fig. 10).
The promontories and embayments along the scarp line have been ascribed by
Brooks to be developed on synclinal and anticlinal swells (see Brooks 1993).
This scarp is structurally composed of cuesta cliff exceeds 45° in slope (Fig. 10).
The cuesta scarp overlooks Dakhla Depression and facing south (see Fig. 11), while
the gentle slope faces towards northwestern direction till it reaches Farafra Depression. Most of the tabular surfaces behind the cuesta wall are covered by sand dunes
53
According to the above mentioned study this pediplain reaches a huge stretch
(70,000 km
2 ) and is dissected by many E-W faults giving rise to scarps of low
altitudes, 40–50 m above the surface of the desert, isolated hills, ridges and many
small local depressions. The altitude of this pediplain ranges from 100 m amsl at its
eastern side near Kharga scarp to 500 m amsl near the twin hills of Abu Ballas at the
edge of the Sand Sea (see for more details Issawi et al. 2009).
Dakhla depression is also geophysically connected with the wider region. In
their research about the Nubian Sandstone Aquifer System (recharge, depletion, and
connectivity) Mohamed et al. (2016) studied the other sub-basins: Dakhla, Northern
Sudan Platform, and Kufra.
The importance of Dakhla exceeds its regional geomorphology to the global
one, especially with respect to paleogeography. According to Moawad et al. (2008)
Mawhoob area revealed a prominent accumulation of vertebral bones that delineate outlines of huge vertebral animals (more than 10 m in length) indicating that
these skeletals were associated with large vertebrates that lived during the Mesozoic
period. The previously mentioned study concluded that these animals are reaching
its climax through the Upper Cretaceous and extinct by the close of the Cretaceous
time.
The importance of this discovery lies in its standing mostly upon two facts; the
first is the intact relationship of these bones. The second is the stratigraphic position
where these bones were accumulated. The bones herein precisely mark the (K/T)
boundary (see for details Moawad et al. 2008).
These results were affirmed by recent findings of skeletons of dinosaurs in Teneida
area (Eastern Dakhla), which becomes world widely known as Mansourasaurus: a
Late Cretaceous dinosaur dispersal between Europe and Africa (see for more details
Sallam et al. 2015).
3 Principal Geomorphological Units
3.1 Plateau and Escarpment
The tabular landscape of the Western Desert of Egypt is known in the previous literature as “the Libyan plateau” where the most prominent geomorphological landmark
in the study area is a transverse scarp wall generally runs ESE-WNE for about 300 km
(see Fig. 10).
The promontories and embayments along the scarp line have been ascribed by
Brooks to be developed on synclinal and anticlinal swells (see Brooks 1993).
This scarp is structurally composed of cuesta cliff exceeds 45° in slope (Fig. 10).
The cuesta scarp overlooks Dakhla Depression and facing south (see Fig. 11), while
the gentle slope faces towards northwestern direction till it reaches Farafra Depression. Most of the tabular surfaces behind the cuesta wall are covered by sand dunes