The Eastern Desert
The Eastern (Arabian) Desert, which in its southern extension is known
as the Nubian Desert, consists in large part of the Red Sea Hills. These
reach their maximum elevation in Gabal Shayeb el-Banat (2,187 m), while
the northern parts are less high and consist mostly of Tertiary and Mesozoic
rock formations. The escarpments formed here are interrupted by the fault of
Wadi Araba. To the south the overlying layers were mostly eroded owing to
an uplift, so that the Basement Complex forms the surface in nearly all parts
between the Nile valley and the Red Sea. Unlike in the Western Desert, deep
valleys are incised in the Eastern Desert. This is due partly to the greater relief
dynamics and partly to the lesser permeability of the Basement Complex,
which mostly consists of crystalline rock. The deeply cut old wadis, which
are reactivated whenever erratic rainfall occurs, have steep slopes, and many
of them are filled mainly with fluvial and aeolian sands. They are used by the
few Bedouin living in the Eastern Desert for grazing their herds.