By Nompumelelo Kubheka
An earthquake with a 5.5 magnitude has been felt throughout the country on Tuesday, 6 August killing one man, injuring 34 mine workers and damaging buildings.
The earthquake was felt in Johannesburg, Durban and Cape Town and with the epicentre in the Orkney area in the North West.
One man was killed when a wall collapsed on him in, 34 mine workers were injured while hoisted to safety along with 3 300 workers at AngloGold Ashanti mines and at least 400 houses have been damaged in Orkney according to news24 report.
Buildings shook in Johannesburg and surrounding area. Clinics and schools had to close in Orkney.
So what caused this tremor?
Dr Herman van Niekerk, a specialist in structural geology at the department of geology at the University of Johannesburg, told Beeld that the African continent is slowly ripping apart, with a giant tear stretching from the Rift Valley to northern Mozambique.
According to Beeld, these movements place stress on the Earth's crust, which needs to release this stress somewhere, and on Tuesday it happened near Orkney.
The eastern section of this tear is moving away from the rest of the continent at about 2.5cm per year, according to The Basement Geographer. The tear will eventually result in a new tectonic plate and a new continent containing most of Africa's east coast, known as the Somali plate.
So it is not the mining activity that caused the quake, pointing out that the epicentre was 10km underground, while the deepest mines in the area were only 4km deep according to Herman.
The Council for GeoScience, Michelle Grobbelaar also told Eyewitness News that the quake was not related to mining or fracking, saying the area had experienced earthquakes in the past. She added that the depth of the quake caused the tremor to spread widely, which is why it was felt over large parts of the country
Michelle Grobbelaar further stated that Durbanites got a taste of the earthquake because the beach sand tends to amplify the ground motion.
What should you do after an earthquake, according to news24:
· Establish if you have sustained any injuries. Check around you and try to see if anyone else sustained any injuries. If you can provide first aid, proceed to do so.
· Call emergency services for medical assistance if someone sustained an injury.
· If the building you are in sustained structural damage, even if you are unsure, evacuated calmly and quickly. (If possible)
· Try and listen to your local radio station for emergency or news updates.
· Do not enter any damaged buildings or areas. There might be debris lying around. Be very careful around broken glass and other items that can cause you harm. Do not take off your shoes.
· Stay away from beaches until the area has been announced as safe.
· If the area you are in has an evacuation or emergency plan, try and follow it.
Things to do during earthquakes:
- Stay calm.
- Try and stay where you are.
- Use large and sturdy objects such as a big desk to crawl under.
- If you are in a building, try and stand with your back against the wall near the centre of the building.
- Stay away from windows and outside doors.
- Should you be outside at the time of an earthquake, look around you. Ensure you are clear from power cables or anything overhead that might fall on you. Do not stand near or against a building, debris might fall on top of you.
- Use the stairs to evacuate premises (only when it is safe to do so)
Other things you should know about earthquakes:
- At the earth’s surface, earthquakes manifest themselves by shaking and sometimes displacement of the ground.
- They are caused mostly by rapture of geological faults. Other events such as volcanic activity, landslides, mine blasts and nuclear tests may trigger them.
- Magnitude 3 or lower earthquakes are mostly imperceptible or weak and magnitude 7 and over potentially causes serious damage over larger areas, depending on their depth.