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WEEKLY NEWSLETTER
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Saudi Arabia
Index
Three great deserts isolate Najd from north, east, and south
as the Red Sea escarpment does from the west. In the north, the
An Nafud--sometimes called the Great Nafud because An Nafud is
the term for desert--covers about 55,000 square kilometers at an
elevation of about 1,000 meters. Longitudinal dunes--scores of
kilometers in length and as much as ninety meters high, and
separated by valleys as much as sixteen kilometers
wide--characterize the An Nafud. Iron oxide gives the sand a red
tint, particularly when the sun is low. Within the area are
several watering places, and winter rains bring up short-lived
but succulent grasses that permit nomadic herding during the
winter and spring.
Stretching more than 125 kilometers south from the An Nafud
in a narrow arc is the Ad Dahna, a narrow band of sand mountains
also called the river of sand. Like the An Nafud, its sand tends
to be reddish, particularly in the north, where it shares with
the An Nafud the longitudinal structure of sand dunes. The Ad
Dahna also furnishes the beduin with winter and spring pasture,
although water is scarcer than in the An Nafud.
The southern portion of the Ad Dahna curves westward
following the arc of the Jabal Tuwayq. At its southern end, it
merges with the Rub al Khali, one of the truly forbidding sand
deserts in the world and, until the 1950s, one of the least
explored. The topography of this huge area, covering more than
550,000 square kilometers, is varied. In the west, the elevation
is about 600 meters, and the sand is fine and soft; in the east,
the elevation drops to about 180 meters, and much of the surface
is covered by relatively stable sand sheets and salt flats. In
places, particularly in the east, longitudinal sand dunes
prevail; elsewhere sand mountains as much as 300 meters in height
form complex patterns. Most of the area is totally waterless and
uninhabited except for a few wandering beduin tribes.
Data as of December 1992
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