Science and Technology Education Centre
(STEC@UKZN)

Geology of KZN

The geology of KZN records 3 500 million years of geological history. To find out more details about the geology of a specific stratigraphic unit or event click on one of the buttons below. For example, if you want to read more about the Zululand Group, select the orange button labelled Zululand Group below.

This map is simplified and modified from 1:1 000 000 scale geology map sheets (Geological Survey, 1984, Pretoria, Government Printer, NE & SE sheets). For a more detailed explanation of the local geology and more detailed maps contact the  Council for Geoscience.

Cross sections

Cross sections

Geological cross-section from Kranskop to Swaziland (top) and from the Drakensberg Escarpment to Durban (bottom)

Geological Timescale

Geological units in KZN are shown as coloured blocks indicating their relative age and corresponding period of the timescale. Also shown is their relationship to the evolution of organisms and major extinction events in Earth’s history. 

timescl

Faulting and Uplift - Gondwana breaks up

KZN fault system

Schematic map of faults in KZN

The rift along the KwaZulu-Natal coast eventually widened into a narrow ocean similar to the present day Red Sea. Over millions of years this feature opened further to form the Indian Ocean. Evidence for this rifting is seen by the numerous faults which are concentrated along coastal KwaZulu-Natal. The largest of these – the Tugela Fault, has exploited the weakness formed between the Kaapvaal Craton and Natal Metamorphic Province. 

Gondwana

Evidence that Gondwana existed: distribution of fossils , matching mountain ranges and glaciation pattern.

Kimberlite pipes - but no diamonds in KZN (Cretaceous)

Following Gondwana breakup, there was a period of unique igneous activity. This formed numerous volcanoes of kimberlite rock, commonly known to contain diamonds.  

Unfortunately, the kimberlite pipes of KwaZulu-Natal have not yielded any significant diamonds. This is due to the kimberlites having originated from beneath the Natal Metamorphic Province. Carbon crystallises to form diamond under high pressure and low temperature – conditions only found beneath the Kaapvaal Craton, such as in northern Lesotho.   

GEM_KZNGeolkimber_h

Schematic map of Kimberlite pipe locations.

GEM_KZNgeolkimbvolh

The schematic diagram shows the structure of a KZN kimberlite pipe, indicating the erosion levels in Lesotho and in KZN. 

Letseng Diamond Mine, Lesotho
Diamond, Letseng