1028 EARTHQUAKES AND RELATED GEOHAZARDS IN AFRICA
Dr Chris Hartnady, geologist, Umvoto Africa
In 1915 and 1932 earthquakes of 6.8 magnitude occurred in the central Mozambique Channel and off Cape St Lucia in KwaZulu-Natal. With such large events in its recent tectonic past, Africa cannot afford a false sense of security about the maximum size of future earthquakes. This five-lecture course will give an historical overview of significant African earthquakes and the tectonic framework of seismicity within which they occurred. It will introduce participants to the East African Rift System, the divergent plate boundary between Nubia and Somalia often cited as a modern archetype for continental breakup. Mining-induced seismicity has long been associated with gold-mining on the Witwatersrand, and pressure created by holding back billions of tons of water has led to reservoir-induced earth tremors at the Kariba dam on the Zambezi River after impoundment in 1959 and Katse dam in Lesotho after October 1995. The course will end with an assessment of the geohazards – volcanoes, landslides and tsunami – associated with earthquakes in Africa.
1. Historical overview of significant African earthquakes
2. Tectonic framework of African seismicity
3. Evolution and plate-kinematics of the East African Rift System
4. Natural and induced earthquakes in southern Africa
5. Associated African geohazards
Hartnady, C. 2002. Earthquake hazard in Africa: perspectives on the Nubia–Somalia boundary.
Hartnady, C. 2014. Fracking Rocks (and Rolls!).
Meghraoui, M. et al. 2016. The Seismotectonic Map of Africa.