Continuing its successful public lecture series, UKZN’s College of Agriculture, Engineering and Science (CAES) hosted a virtual public lecture delivered by Land Surveying lecturer, Dr Mayshree Singh and PhD candidate and Land Surveying lecturer, Mr Thando Nqasha that delved into what causes the earth to move, interesting earthquake research and implications for KwaZulu-Natal.
Themed: What Do Scientists Do? A Look Inside the Ivory Tower, the series features UKZN scientists working in the CAES and the co-ordinator of the Science and Technology Education Centre (STEC @UKZN) Dr Tanja Reinhardt, who facilitates the lectures.
Said Singh: ‘It is a great pleasure to be able to communicate our research to you in the hope of educating the general public on earthquakes in the region and raising awareness of the ways we can improve resilience to the devastating effects they have.’
Singh, who directs the Maya Geophysics consultancy and teaches Hydrographic Surveying and Introduction to Geomorphology courses at UKZN as well as supervising postgraduate students, is interested in seismo-tectonics which examines the causes of earthquakes from a geological and geophysical perspective. She has over 20 years’ experience in research and industrial aspects of probabilistic seismic hazard and risk.
Nqasha is a contractor at Maya Geophysics and a lecturer at UKZN – he holds a Master’s degree in Land Surveying from the University – and his PhD research is focused on factors that contribute to the damage caused to low cost homes by earthquakes. He has done extensive research into the earthquake directional effects of the 2014 earthquake in the North West Province town of Orkney.
Their presentation gave insight into earthquake research at UKZN, the causes of earthquakes and terminology used to describe them, historical earthquakes in South Africa and KZN, the directional effects of earthquakes, the Haiti earthquake that featured in recent news, and how participants could contribute to earthquake research and resilience.
Singh introduced research projects underway at UKZN including an underwater heritage mapping project, the use of UKZN’s seismic station, and applied research that is of use to society and industry through collaborative consulting projects that involve probabilistic seismic hazard assessments.
She said skills being developed at UKZN could assist in understanding what is happening on the sea floor and thereby contribute to earthquake research and monitoring.
Earthquake research at UKZN involves the collection of relevant historical and instrumental earthquake data, fieldwork after large earthquakes, investigation of damaged structures, development and modification of specialised toolboxes, and research into the causes and mechanism of earthquakes.
‘The large earthquakes that we have in South Africa are in the region of about magnitude six; an earthquake of this magnitude will occur around 150 times a year worldwide, but the energy release is still equivalent to the energy released by the Hiroshima atomic bomb, so it can be quite destructive,’ said Nqasha.
He noted that South Africa had a good seismological monitoring network, while Singh said South Africa had relatively low levels of seismicity and described the different kinds of earthquakes that occurred in the country, highlighting the use of historical records to understand the hazards and risks for regions.
The duo covered the effect of a 2016 seismic event that occurred in KZN and impacted on low-cost housing, the reasons for South Africa’s lower magnitude earthquakes, and the need for increased seismic monitoring and mapping of neotectonic faults to identify the causes of small seismic events in KZN. Nqasha discussed the earthquake directional effect on infrastructure, and how understanding this can reduce the vulnerability of structures being damaged in earthquakes.
The public lecture series will continue in October with Professor Colleen Downs presenting on the topic: Adapt or Die! – The Persistence of African Wildlife in Urban KZN.
Words: Christine Cuénod