Bilma is located in the Kaouar Valley in the Ténéré desert. The place is an oasis with numerous shallow smaller lakes and streams leading to them. Numerous fish cavort in the waters. There is a phenomenon in the entire Kaouar Valley: salt water and fresh water push upwards at short intervals. Due to complex fracture tectonics in this part of the Ténéré Desert, water from great depths penetrates sloping rock layers through artesian pressure. Where it flows through saline layers from the Cretaceous period, it reaches the surface as a saline solution and, after being greatly reduced by evaporation, is used for salt production. Otherwise, the date palms use the groundwater and therefore do not need any additional irrigation. - Kaouar - Ténéré - Niger - 1968
Bilma is located in the Kaouar Valley in the Ténéré desert. The place is an oasis with numerous shallow smaller lakes and streams leading to them. Numerous fish cavort in the waters. There is a phenomenon in the entire Kaouar Valley: salt water and fresh water push upwards at short intervals. Due to complex fracture tectonics in this part of the Ténéré Desert, water from great depths penetrates sloping rock layers through artesian pressure. Where it flows through saline layers from the Cretaceous period, it reaches the surface as a saline solution and, after being greatly reduced by evaporation, is used for salt production. Otherwise, the date palms use the groundwater and therefore do not need any additional irrigation. - Kaouar - Ténéré - Niger - 1968