A Study of Granite Relief from South-West Africa

Abstract

The writer describes the relief forms and destructional processes occurring in a group of granite hills in Damaraland, South-West Africa. The hills are attributed to the dissection of a former erosion surface by rejuvenated streams. Drainage incision has followed longitudinal and diagonal joint lines, which control the orientation and sub-division of individual groups of granite domes. The destruction of granite masses by plating, or the unloading of Unweathered shells, produces the dome outline, whereas the development of vertical jointing leads to granite tors. Domes may be cleaved along transverse joints to form secondary domelets, or split longitudinally to form narrow whalebacks. The former are lowered by plating to flat dome forms the latter are reduced by marginal fracturing, here termed mural weathering. Further wastage is by slow granular disintegration on low granite outcrops.