An expanded land of 80 000 KM2 of sand, the big occidental desert is like how
we can imagine it a huge and without any charm surrounded by the M'zab in the
east; by the SAOURA valley in the west, it is looks like an impassable barrier
between the Saharian atlas & Taidmait in the south. This alluvium sand «
which is not transported by the wind » has been accumulated in quaternary to
became now a day these huge changeable dunes.