Borkou

a desert region in the northeast of the Chad Depression in the Sahara (Republic of Chad). It borders on the Tibesti Massif to the north, the Erdi Plateau to the east, and the Bodélé Depression to the south. On the west, it merges with the plains of Kavar, in contrast to which the surface of Borkou is slightly sandy. Most of the area is occupied by accumulative plains of an elevation of 200–400 m sloping down to the south. Borkou runs into cuesta ridges (elevation, 400–700 m) on the north. Vegetation, concentrated along the beds of wadis (streams) and in sinkholes, consists of doom palm groves, acacia groves, fig palms around oases, and fig trees. There is nomadic animal husbandry and salt extraction.