The origin of the southern Namaqualand gneiss complex, South Africa, in the light of geochemical data

Abstract:

The Namaqualand granite-gneiss complex in South Africa covers an area of approximately 70,000 km2. The southern portion consists of mainly mesozonal biotite gneiss and a fine-grained granulite. Geochemical data suggest that regional metamorphism and possibly partial mobilisation of mainly arkosic rocks of the Kheis System gave rise to the basement gneiss in which remnants of the transformed sediments are still preserved. There is no evidence for large-scale metasomatic granitisation which, according to previous authors, transformed the original sediments into the gneisses. Petrological considerations strongly support the conclusion that the sediments of the previously called 'Malmesbury Formation' cannot be the parent rocks of the gneiss complex. © 1971.

Año de publicación:

1971

Keywords:

Fuente:

scopus