stripes
Musensi forms a small hill of 2.5x1 km consisting predominantly of K-feldspar rock. Mbulu, a smaller hill about 1 km to the south, is composed of the same rock type; a further small area of this rock outcrops 2 km to the west of the southern end of Musensi. The rock consists of euhedral to rounded phenocrysts of K-feldspar in a matrix of the same material with some larger biotite crystals. One outcrop of nepheline tephrite is reported and drilling intersected carbonatized and feldspathized biotite pyroxenite in which the carbonate may form as much as two thirds of the rock. There is a swarm of feldspathic dykes extending up to 10 km from the hill. Small plugs of breccia consisting of country rock fragments occur around the occurrence.
GITTINS, J. 1966. Summaries and bibliographies of carbonatite complexes. In: O.F. Tuttle and J. Gittins (eds), Carbonatites. 417-541. John Wiley, New York. MILLER, J.A. and BROWN, P.E. 1963. The age of some carbonatite igneous activity in south-west Tanganyika. Geological Magazine, 100: 276-9.
