Investigations into two earthquakes that struck in Botswana and Stilfontein – a mining town situated between Klerksdorp and Potchefstroom – in April, are ongoing, with geological experts confident of no further seismic activity expected in Joburg.
City Buzz reported previously that the Stilfontein event measured at magnitude 4.6, resulting in seismic activity spreading out to parts of Joburg and causing fear among residents. No prior warnings had been issued by the South African Weather Services.
Read: More tremors could follow quake
Susan Webb, associate professor of geophysics at the School of Geoscience at Wits University, told City Buzz that since the occurrences, investigations conducted using radar technology have turned up specific fault areas where seismic activity was recorded. “Investigations have uncovered the extent of surface deformity in these areas, however, peer reviews and publications are yet to verify these findings,” she said.
Read: Expert: Tremor, not earthquake in Jozi
“A team comprised of African scientists has been sent to Botswana to deploy a temporary seismic network to record aftershocks. Interestingly, it’s the first time that an African response team has gone out since it’s usually a European or American-based company that oversees such expeditions.”
Read: Tremor shakes Joburg
Webb added that the occurrence of earthquake activity in Joburg was unusual. “The ground that we’re on is not on a plate boundary and so we generally don’t [experience] a lot of earthquakes,” which according to the professor does not preclude the possibility of seismic activity.
“The earthquake in Botswana was a fairly large event that occurred in an area that is not usually seismically active. However, ongoing location studies are being conducted in order to determine what the relationship of the Stilfontein event is to the [surrounding] mining areas.”
