Tarso Toon is a volcano in the central Tibesti mountains. The volcano reaches a maximum height of 2,575 metres and a width of 21 by 19 kilometres, covering a surface of 600 square kilometres. It also features a caldera 11 by 12 kilometres wide, with a gap on its northern side. It was active in the Miocene, developing over older ignimbrites with tholeiitic rocks. Later, felsic volcanic rocks were emplaced within the caldera and the Voon ignimbrite buried parts of the tholeiite.