ABSTRACT
Valleys in the desert plateau, forming a complex network were created mainly by rare but violent floods such as the case of M’zab valley, or by the permanent flow of water such as Labiod valley. The valley of M’zab is one of the greatest valleys in this net and is situated roughly in the middle. It is about 20 km long, 0.4 and 2 km wide, with a depth varying between 100 and 150 m, and is dry in summer (Bouchair 2003). Labiod valley where the Ghoufi balconies settlements are implanted is about 4 km long, 0.35 km wide and about 60 m deep. Width and depth increases as water is added from tributaries.
