Saturday 12 August 2017

Magnitude 4.8 Earthquake in Kweneng District, Botswana.

The United States Geological Survey recorded a Magnitude 4.8 Earthquake at a depth of 10 km roughly 56 km to the northeast of the village of Botlhapatlou in Kweneng District, Botswana, at slightly after 4.35 am local time (slightly after 2.35 am GMT) on Saturday 12 August 2017. This is a large Earthquake by Southern African standards, and was felt across most of eastern  Botswana, as well as in South Africa as far away as Johannesburg, though there are no reports of any damage or casualties.

The approximate location of the 12 August 2017 Kweneng District Earthquake. USGS.

Earthquakes are rare in Southern Africa, making this one of the largest Earthquakes ever recorded in the country. Because of this rarity it is hard to make precise judgements about the cause of quakes in the region, due to a paucity of data. Botswana is close the southern end of the Great Rift Valley exits the continent and passes out under the Indian Ocean. The Great Rift Valley is slowly splitting the African Plate in two allow a line from the Red Sea through Ethiopia, and which includes the great lakes and volcanoes of east-central Africa. This has the potential to open into a new ocean over the next few tens of millions of years, splitting Africa into two new, smaller, continents; Nubia to the west and Somalia to the east.  

Movement on the African Rift Valley, with associated volcanoes. Rob Gamesby/Cool Geography.

Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.
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