An earthquake of magnitude 3.3 occurred at 23:15 on Friday, 28 km east of Viljoenskroon, Fezile Dabi District Municipality in the Free State.

According to the European-Mediterranean Seismological Centre (EMSC), the quake was located at a shallow depth of 10 km.

Shallow earthquakes are felt more strongly than deeper ones as they are closer to the surface.

Cities and towns close to the epicentre may have experienced very weak shaking. Image: Volcanodiscovery

The exact magnitude, epicentre, and depth of the quake may be revised as seismologists review data and refine their calculations. Other agencies may also issue their own reports*.

Cities and towns close to the epicentre may have experienced very weak shaking, said the EMSC. This would have included Vredefort (pop. 14 600), Viljoenskroon (pop. 55 000), and Parys (pop. 71 300).

Other areas further away, like Potchefstroom (pop. 123 700), Stilfontein (pop. 93 100), and Kroonstad (pop. 104 000) likely did not feel the quake, the agency added.

SOUTH AFRICA GETS THE SHAKES

A series of small quakes has rattled the Republic in 2024, without major incident.

A light magnitude 3.2 earthquake was reported in parts of Johannesburg on 6 February.

According to Volcano Discovery, the quake hit 8.7km away from Westonaria, Gauteng, at a very shallow depth of 5km and was felt widely in the area.

Meanwhile in Cape Town, social media platforms were abuzz with reports of a loud rumble or bang heard from various parts of the city on 27 March.

The Council for Geoscience (CGS) eventually confirmed that a mild earthquake, with a magnitude of 1.4, had in fact struck the Mother City.

CAN EARTHQUAKES BE BLAMED ON MINING ACTIVITY?

South Africa isn’t famous for major seismic activity. Yet the country has a surprising history of significant tremors and earthquakes and most of these have occurred around the mining belt.

In the wake of the damaging magnitude 4.9 Orkney quake of 2014, Professor Andrzej Kijko of the University of Pretoria’s Natural Hazard Centre said that 95% of South Africa’s tremors were caused by mining, especially around the areas of Klerksdorp, Welkom and Carletonville.

“Mining in South Africa is leading to enormous stress factors being created. If there is a natural fault weakness 6km underground, the stresses caused by mining can easily activate it,” he said.

*magnitude, epicentre, and depth accurate at time of publishing.

source:What was that? Small earthquake hits near Free State town (thesouthafrican.com)