Is Africa really going to split into two?
Almost 335 million years ago, there existed one giant mass of land on earth. It was a supercontinent called Pangaea. Around 175 million years ago, Pangaea started to break apart because of continental drift: the shifting of the nine major and a large number of smaller tectonic plates on the surface of the earth.
It split into Laurasia (which became North America and Eurasia) and Gondwana (which became the remaining continents). And thus we have the world as we know it, or as humanity has ever known it to be. That may soon change.
When we say soon, we mean 50 million years. But the signs have begun to make themselves visible.
On March 19, following heavy rain and seismic activity it witnessed, the bustling Maai Mahiu-Narok road in the ominous-sounding Great Rift Valley in Kenya was struck by a deep crack. According to Daily Nation, a local news outlet, the tear measures 50 feet deep and 65 feet wide in some spots and stretches for several miles. And it is supposedly still growing.
According to geologist David Adede, previously, the crack was likely filled with volcanic ash from nearby Mt Longonot. This means the space was only exposed when rainwater washed the ash away. “The valley has a history of tectonic and volcanic activities,” said Adede.
Wait? So does that mean the planet will soon have a new continent? Not quite.
What is the deal with Africa?
There is much change that the cradle of humanity is witnessing, and not just politically and culturally. The real tumult is happening beneath our gaze, under the land masses, and has everything to do with tectonic plates. To understand the phenomenon, one needs to understand what is happening to the Great Rift Valley.
The continent of Africa does not sit on one major continental plate. Four countries in the Horn of Africa — Somalia and half of Ethiopia, Kenya and Tanzania — sit on top of a smaller plate commonly referred to as the Somali Plate. The rest of the continent sits on what is commonly called the Nubian Plate, to avoid confusion.
The East African Rift Valley, which stretches over 3,000km from the Gulf of Aden in the north towards Zimbabwe in the south, splits the African plate into two unequal parts.
According to a recent report by Lucia Perez Diaz, a postdoctoral researcher at the Fault Dynamics Research Group at Royal Holloway, University of London, continental rifting requires the existence of extensional forces massive enough to break the lithosphere. The report adds that in the case of the East African Rift — an active type of rift, in which the source of stresses lies in the circulation of the underlying mantle — the rise of a large mantle plume “is doming the lithosphere upwards, causing it to weaken as a result of the increase in temperature, undergo stretching and breaking by faulting”.
Diaz adds that “although most of the time rifting is unnoticeable to us, the formation of new faults, fissures and cracks or renewed movement along old faults as the Nubian and Somali plates continue moving apart can result in earthquakes”.
But are we going to see new continents being born?
Nope.
This process may take anything up to 50 million years. Diaz himself admits that while the continental split will take place someday, “dramatic events, such as sudden motorway-splitting faults or large catastrophic earthquakes may give continental rifting a sense of urgency but, most of the time, it goes about splitting Africa without anybody even noticing”.
There are also other things at play, and according to an extensive report in The Guardian, much of it was based on unsubstantiated rumours and science taken out of context. For example, as Austin Elliott, a postdoctoral academic at the NERC Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics, pointed out, the rift was “no tensile crack” but “an eroded out gully; there are parts of it clearly visible in the video that haven't been eroded yet, and certainly aren't extended”.
Quite simply, the crack was formed by sudden erosion and not by extension along active geological faults. This could also be confirmed by satellite imaging — similar erosions can be seen elsewhere in the region, suggesting that the flash flood events have caused erosion before.
The Guardian pointed out that reports of seismic activity were unsubstantiated, adding that there have been no official reports of earthquakes from authorities within Kenya.
The National Geographic, like Diaz, too notes that eventually, the Somali plate would completely separate from the Nubian plate and form a separate land mass comparable to Madagascar or New Zealand. Fortunately for those who live there, that separation isn't expected to happen for a long time now. Geology is a slow process, after all.