Drakensberg Group
   

Dramatic outpourings of lava spread across much of Gondwana about 180 million years ago heralding the start of Gondwana breakup.

A 1.5 kilometre thick accumulation of Jurassic age basalt flows can be seen along the Drakensberg Escarpment. The magma (molten rock) made its way to the surface along a complex system of fractures.

Crystallisation of magma within these fractures formed dolerite sills and dykes.

 

Dolerite dyke in basalt lava

Sills are horizontal and dykes are vertical intrusions of igneous rock. Dolerite sills are common throughout inland KZN in sedimentary rocks of the Karoo Supergroup.

 

  

The sills often form flat areas and weather to form a very dark red soil. The sill may also form resistant cliffs such as at Howick Falls. 

Amphitheatre, Drakensberg Mountains

 Howick Falls 

Howick Falls

(Source: http://en.wikipedia.org/w iki/File:Howick-Falls -November-2009.jpg)

Basalt River Boulders

Basalt River Boulders


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