The tectonostratigraphy, granitoid geochronology and geological evolution of the Precambrian of southern Ethiopia

Abstract

Two distinct tectonostratigraphic terranes, separated by repeatedly reactivated deformation zones, are recognised in the Precambrian of southern Ethiopia: (1) granite-gneiss terrane, which is classified into sub-terranes and complexes, and (2) ophiolitic fold and thrust belts. The granite-gneiss terrane consists of para- and orthoquartzofeldspathic gneisses and granitoids, intercalated with amphibolites and sillimanite-kyanite-bearing schists. The paragneisses resemble gneisses from northern Kenya that were derived from sediments that filled the Kenyan sector of the "Mozambique Belt basin" between 1200 and 820 Ma. The volume of sediments formed during this period is comparatively small in so..