Located midway between Lake Chad and the Gulf of Syrte, this caldera volcano is situated in the middle of the volcanic region of Tibesti in Southern Libya and Northern Chad. This region makes a triangle that measures nearly 350 miles in length and is surrounded by the sandstone plains and plateaus of the central Sahara. Toon's caldera has a diameter of around 10 km.
This volcanic complex has the volcanoes Yega, Oyoye, Tieroko and Voon located off to the west and southwest of it.
Grove, A. T.; Geomorphology of the Tibesti Region with Special References to Western Tibesti, p18.
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