The Tibesti Mountains formed through an interplay of tectonic phenomena and volcanism, with the central high sector of the mountains formed by Cenozoic volcanism, while the lower parts were formed during Precambrian to Cenozoic age. The volcanic activity covered an area of about and took various forms, including deep craters, large calderas, shield volcanoes and stratovolcanoes. At Soborom, these volcanics crop out in various series known as the Middle Dark Series, Middle Bright Series and Upper Dark Series.