African continent split likely cause of quake - expert
Johannesburg - An expert says Tuesday's 5.5 magnitude earthquake in Orkney may have been caused by movements of the Earth’s crust in the Rift Valley in Ethiopia.
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.
Dr Herman van Niekerk, a specialist in structural geology at the department of geology at the University of Johannesburg, told Beeld the African continent is slowly ripping apart, with a giant tear stretching from the Rift Valley to northern Mozambique.
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.
Van Niekerk said it was unlikely that mining activity had caused the quake, pointing out that the epicentre was 10km underground, while the deepest mines in the area were only 4km deep.
Van Niekerk told Sapa that the quake, which killed one person, could be considered big, but it was not uncommon.
The Council for GeoScience's Michelle Grobbelaar 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.