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Large Crack in East African Rift is Evidence of Continent Splitting in Two (pbs.org)
A large crack, stretching several miles, made a sudden appearance recently in south-western Kenya. The tear emerged after heavy rains caused havoc in the nation last month, which also saw neighborhood get flooded and major highways closing off. The downpour also exposed a fault line that geologists now say is evidence that the African continent will split into two over the next tens of millions of years. From a report: The Earth is an ever-changing planet, even though in some respects change might be almost unnoticeable to us. Plate tectonics is a good example of this. But every now and again something dramatic happens and leads to renewed questions about the African continent splitting in two. The Earth's lithosphere (formed by the crust and the upper part of the mantle) is broken up into a number of tectonic plates. These plates are not static, but move relative to each other at varying speeds, "gliding" over a viscous asthenosphere.
[...] The East African Rift Valley stretches over 3,000km from the Gulf of Aden in the north towards Zimbabwe in the south, splitting the African plate into two unequal parts: the Somali and Nubian plates. Activity along the eastern branch of the rift valley, running along Ethiopia, Kenya and Tanzania, became evident when the large crack suddenly appeared in south-western Kenya. When the lithosphere is subject to a horizontal extensional force it will stretch, becoming thinner. Eventually, it will rupture, leading to the formation of a rift valley. This process is accompanied by surface manifestations along the rift valley in the form of volcanism and seismic activity. Rifts are the initial stage of a continental break-up and, if successful, can lead to the formation of a new ocean basin.
[...] The East African Rift Valley stretches over 3,000km from the Gulf of Aden in the north towards Zimbabwe in the south, splitting the African plate into two unequal parts: the Somali and Nubian plates. Activity along the eastern branch of the rift valley, running along Ethiopia, Kenya and Tanzania, became evident when the large crack suddenly appeared in south-western Kenya. When the lithosphere is subject to a horizontal extensional force it will stretch, becoming thinner. Eventually, it will rupture, leading to the formation of a rift valley. This process is accompanied by surface manifestations along the rift valley in the form of volcanism and seismic activity. Rifts are the initial stage of a continental break-up and, if successful, can lead to the formation of a new ocean basin.
Seems I've heard of the East African Rift Valley for, like, decades. Only 'news' here is rain washed sediment away and people could see a fault. The entire rift is a fault zone.
It's a crack several miles long that wasn't there a couple of weeks ago. That is, in fact, pretty damn sudden.
The only new thing is the crack. The fact that Africa is splitting up along the rift valley has been known for decades - I learnt about it in a first year geology lecture as an undergrad.