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Tioueine is one of a number of concentrically zoned plutons, known locally as the Taourirt granites, which intrude Upper Proterozoic rocks of the central Pharusian belt of the Hoggar. It comprises four concentric units: a large outer perthite-ferroedenite granite which grades into a granite of alkali feldspar, oligoclase, biotite and rare ferroedenite. Both are cut by arcuate dykes of granite, containing ferroedenite, some riebeckite and secondary actinolite, and syenite containing in addition hedenbergite and ferrohedenbergite. The core, which intrudes these three units, is a monzonitic biotite-ferroedenite-ferrohornblende granite.
AZZOUNI-SEKKAL, A. and BOISSONNAS, J. 1985. Geochemistry of the Tioueine Pan-African granite complex (Hoggar, Algeria). Thirteenth Colloquium of African Geology, St Andrews. Occasional Publication,International Center for Training and Exchanges in the Geosciences, 1985/3: 140-1.