One person was killed and 17 injured when a 5.5 magnitude earthquake hit South Africa on Tuesday, causing scares in mining operations and evacuations in parts of the country.
“For South Africa, a 5.5 magnitude quake is quite big but it’s not uncommon,” said Herman van Niekerk, a structural geologist at the University of Johannesburg.
“It went on for about 20 seconds or so, but some people say they felt it for a lot longer,” he told Sapa.
The quake, one of South Africa’s largest magnitude earthquakes in the past decade, was felt as far way as Mozambique and Botswana. The Council for Geoscience said its epicentre was in the Orkney region in North West province, where one person was killed.
“It occurred in the Stilfontein, Klerksdorp, and Orkney region and it was quite widely felt… as far as the Eastern Cape,” said the council’s Michelle Grobbelaar.
She said more tremors, aftershocks and possibly a second quake of the same magnitude were expected in the coming days, but it was unknown when.
“We are monitoring. It will continue for days, if not months,” she said.
“More tremors are expected. We can expect one of the same magnitude in future, we just don’t know when. We cannot predict.”
At least 400 houses were reportedly destroyed by the earthquake that hit the area of Orkney in the North West on Tuesday, premier Supra Mahumapelo told reporters.
“We have heard of 400 houses that have been affected in the area,” said Mahumapelo.
ER24 spokeswoman Luyanda Majija said the body of a 31-year-old man was found in an old mining village in Orkney following the quake.
“He was found lying under some debris,” she said.
She said there was no new information regarding any other injuries or deaths by Tuesday evening.
Mamosa Melato, a resident of Orkney, said she thought the world was ending during the quake.
“I ran outside and saw the ground cracking. The toilet seat was dislodged from the plumbing system and water was everywhere,” she said.
Melato’s neighbour was also affected by the earthquake. Emergency personnel cordoned off both houses. While outside, two aftershocks were felt and residents were told not to enter their houses. Citizens in Gauteng, KwaZulu-Natal, and the Free State reported feeling the quake. According to AngloGold Ashanti, 17 employees at its Vaal River operations were injured.
“Early indications are that 17 of our employees at the Great Noligwa and Moab Khotsong mines sustained minor injuries and are being attended to on site by emergency medical staff.”
The mine said it had no further updates on the employees by Tuesday evening. The eThekwini metro in KwaZulu-Natal said a tremor struck the city about eight minutes after the earthquake registered at its epicentre.
“There was spontaneous evacuation within the city centre where the effect was felt, particularly in high-rise buildings. No reports of damage or injury have been received,” spokeswoman Tozi Mthethwa said.
KwaZulu-Natal co-operative governance MEC Nomusa Dube-Ncube said disaster management centres throughout the province were put on high alert.
“We have activated all our systems and resources. Our disaster management facilities are monitoring the situation closely and we are ready to intervene in any part of KZN with speed should it become necessary,” Dube-Ncube said.
In Durban the 32-storey Durban Bay House, one of the tallest buildings in the city, was evacuated. Johannesburg emergency services spokesman Robert Mulaudzi said the quake was felt in most parts of the city. However by Tuesday evening there were no reports in the metro.
“We did not receive any reports on incidents related to the earthquake.”
In Tshwane, the offices of the public protector and two buildings at the University of Pretoria were evacuated.
Tshwane emergency services said it was “liaising” with geoscientists on the quake and people wanted to know if their buildings were safe.
“Only a building inspector or structural engineer may declare a building safe. Disaster management is not in a position to declare buildings safe for re-occupation,” it said in a statement.
The Free State government evacuated all public servants from Bloemfontein’s two tallest buildings during the earthquake.
“The director general of the Free State, Kopung Ralikontsane, ordered all public servants immediately to evacuate the government buildings, go home and report for duty the next day,” spokesman Mondli Mvambi said.
Tremors were felt in Bloemfontein, Welkom, Thabong and Kroonstad.
Free State police spokesman Captain Stephen Thakeng said Welkom and Thabong residents phoned in to report shaking houses and broken windows.
He said schools evacuated children from buildings as a precaution.
In Rustenburg, in the North West, structural engineers inspected the municipal office building following the quake.
“The eight-storey building vibrated during the earthquake. The building was evacuated for safety reasons,” municipal spokesman Thapelo Matebesi said.
The Folha de Maputo website in Mozambique reported that a number of buildings in the capital city were evacuated.
According to statistics by data company Lightstone, the first reference to the quake on social media site Twitter was made at 12.23pm, a minute after the earthquake occurred.
At the close of business of Tuesday, the quake was mentioned 12,000 times.
Van Niekerk said the quake was an indication that the earth’s crust was under stress.
“It tells us about the stress conditions in the earth’s crust at the moment, and something is putting it under stress.”
Van Niekerk said one of the “stresses” could be what was happening in the Great Rift Valley, where violent seismic activity was reportedly tearing the continent in two.
“That will cause some other stresses throughout the earth’s crust, and with this stresses you might have very old structures — older than gold mines, which were there billions of years ago — that could be re-mobilised to relieve stresses.”
Van Niekerk said he did not believe that mining was to blame for the quake.
“We’ve had 5.2 [magnitude] in Welkom in 1976, we’ve had 4.7 Carletonville in 1992, and in 2011 we had five magnitude in the Augrabies, in the Northern Cape.”
According to the Council for Geoscience, a 5.3 magnitude earthquake struck the same region in the North West in 2005. More recently, a magnitude four earthquake struck the Johannesburg region in November last year, while one with the same magnitude struck Bela-Bela in Limpopo in December. SAPA