Djourab Depression

geographical feature, Africa

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Last updated

June 25, 2026

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The Djourab Depression is the lowest point within the Chad Basin, a vast inland drainage area in Central Africa. This depression is located approximately 300 miles (480 km) northeast of the modern Lake Chad. The Chad Basin itself is a downwarped section of the Precambrian African Shield, significantly influenced by a large ancient sea known as Mega-Chad. This ancient sea once covered an area of about 154,400 square miles (400,000 square km). The Djourab Depression is part of this geological history, characterized by clay and sand sediments.1

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Chad
Relief and drainage
…of the basin is the Djourab Depression, which is 573 feet (175 meters) above sea level.
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…of the basin is the Djourab Depression, which is 573 feet (175 meters) above sea level.
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Lake Chad
Geology and physiography
…its lowest point in the Djourab Depression, some 300 miles (480 km) away. Lake Chad occasionally overflows into the generally intermittent El-Ghazal River leading into the depression, but it is usually confined by the dune fields of Kanem.
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…its lowest point in the Djourab Depression, some 300 miles (480 km) away. Lake Chad occasionally overflows into the generally intermittent El-Ghazal River leading into the depression, but it is usually confined by the dune fields of Kanem.
Read More