By Lehlohonolo Lehana.
A moderate earthquake has struck in some parts of Johannesburg, Its magnitude and epicenter still unknown with no reports of any damages or injuries.
According to Volcano Discovery, a possible earthquake occurred near Johannesburg on Saturday just before 8:30pm.
“Details of the quake (if it is one) are so far unkown until confirmed by a seismic agency, but the event was reported felt,” Volcano Discovery said.
Expert Ray Durrheim wrote in The Conversation in 2019 that “some of South Africa’s gold and platinum mines are so deep that the great stresses around excavations exceed the strength of the rock, which may rupture suddenly”.
“These can cause shaking strong enough to damage nearby excavations,” Durrheim added.
He also said rock bursts pose a risk to mineworkers and nearby communities. These can happen anywhere where mining is deep enough.
The KwaZulu-Natal region has much seismic activity because of the presence of tectonic plates, which are the outer layers of the earth’s crust broken into large pieces.
The Council for Geoscience believes Gauteng is more stable in terms of its tectonic activity than KwaZulu-Natal or even Cape Town but this is not cast in stone.
The geoscience council and Earthquakelist.org, a resource for earthquakes happening across the planet, both warned that aftershocks should not be ruled out, although they believed these were unlikely and would probably be small if they did occur.
Being a mining city, Johannesburg is no stranger to tremors which is why many residents thought the shaking felt on Saturday was probably just one of them.
Durrheim and his colleagues analysed an earthquake in 2005 whic occurred in Klersdorp. Measuring 5.3, the quake killed two people and injured 58. It was felt in the nearby town of Stilfontein, as well as Johannesburg and a mine close to Klerksdorp.