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Anonymous writes: I am just curious to know. I live in Witfield, Boksburg in Gauteng. Last night we experienced an earthquake that was really intense. This is the second one in two years. I have lived there all my life and have never felt them so strong, thus I can't believe that it's due to the mines in the area. It lasted for about 5 seconds and was so strong that I could see my house make like a wave almost. Just want to know if someone else felt it and what it measured on the Richter scale. Should we be concerned?
SAWDIS - There is no "Earthquake Proof" areas on Earth. Yes, there is always the possibility of a large and destructive earthquake in South Africa.
An earthquake is caused by fault lines releasing energy under the earth's surface. Fault lines are found in the boundaries of two or more tectonic plates.
South Africa, and the rest of Africa, sits inside the African Plate. The closest big fault lines to South Africa is created by the African Plate and Antarctic Plate which is far down in the Southern Ocean. We should take precautions and be ready when an earthquake strike and lets not forget about the threat of a Tsunami should a large earthquake occur in the Southern Ocean.
The Earth will move whether we like it or not. Minor and small fault lines could also be created away from the main fault lines. In 1969 Tulbagh in the Western Cape experienced a devastating earthquake. So there is definitely bound to be another devastating earthquake in South Africa. It is just a question of where and when. Nobody really knows as earthquakes currently cannot be predicted.
It is not known whether this tremor is a pre-shock to a major earthquake. Earthquakes fall into 3 categories. Some have fore-shocks, some show subtle signs, and others have aftershocks. Earthquakes are still not predictable. Some have no warning at all and never show any signs of happening. The third group follow no pattern at all, they go seemingly randomly, and they can not even be estimated. It is very hard to tell which fault will be in which group, and this is why prediction is still impossible. The designation of an earthquake as fore-shock, main-shock or after-shock is therefor only possible after the main event.
Up to now the cause of last night's tremor is still unknown (possibly mine related?) but the SAWDOS would like to advise members of the public to report any further seismic activity to the SAWDOS.
SAWDOS would like to take this opportunity to thank all earthquake observers who send in reports to the SAWDOS . Despite the lack of Richterscale and other seismic information from Geoscience it is imperative that every tremor in South Africa must be reported. To all those who monitors Earthquakes in South Africa, keep up the good work and continue to inform SAWDOS of tremor events. Keep Safe!!
- SAWDOS
There is a possibility that there is no long period of time from now before a very destructive earthquake hits South Africa.
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Definitely something happening! August 2015 was my first time I felt an earthquake that was almost scary. We were just about to leave the work building when it stopped and it started out as though someone was operating a very strong hammer-drill (I thought it was the renovations going on downstairs) and after about almost a minute it was strong enough to make me decide to evacuate and then it stopped.... just after that I sat in my car and the aftershock came that felt like someone was slightly rocking the car like a cradle. This was just next to Pretoria CBD near Steve Biko hospital. Two nights ago nearly two years later now, things were shaking again but I couldn't feel it under my feet this time. I think I saw a figure depicting Africa that showed a fault line reaching well into South Africa... hopefully we don't get a nr 7+ on the richterscale!!
ReplyDeleteDefinitely something happening! August 2015 was my first time I felt an earthquake that was almost scary. We were just about to leave the work building when it stopped and it started out as though someone was operating a very strong hammer-drill (I thought it was the renovations going on downstairs) and after about almost a minute it was strong enough to make me decide to evacuate and then it stopped.... just after that I sat in my car and the aftershock came that felt like someone was slightly rocking the car like a cradle. This was just next to Pretoria CBD near Steve Biko hospital. Two nights ago nearly two years later now, things were shaking again but I couldn't feel it under my feet this time. I think I saw a figure depicting Africa that showed a fault line reaching well into South Africa... hopefully we don't get a nr 7+ on the richterscale!!
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