Description

At Burnt Mountain in southwestern Damaraland, a sheet of dolerite, associated with the Etendeka volcanism, intruded mudstones of the Verbrande Berg Formation, Karoo Sequence. The succession at Burnt Mountain starts of with the Verbrande Berg Formation, consisting of mudstones with coal horizons and sandstone channels. The Verbrande Berg Formation is overlain by coarse fluvial sandstone of the Tsarabis Formation, followed by calcareous mudstone of the Huab Formation. Lacustrine red mudstones of the Gai-As Formation rest on the Huab Formation, and the sucession is capped by the aeolian Etjo Sandstone.

Brief History

The mudstones were originally deposited in a lacustrine environment, and therefore contained carbonaceous material derived from remnants of organisms. During contact metamorphism caused by the intrusion of the hot dolerite magma, the organic material evaporated from the sediments, leaving behind a black, clinker-like rock, mainly composed of fritted clay minerals. A secondary coating of manganese minerals adds a purple luster to the black rocks. In contrast, the sediments show all shades of white, yellow and red, and this dramatic combination of colours, coupled with the lack of vegetation, has resulted in the name “Burnt Mountain”.