A rift in Kenya is threatening to split up the African continent

The Earth, with its species, is ever changing and evolving, sometimes going on at a rate that is almost unnoticeable to humans until it is evident. Plate tectonics is a good example of this and has renewed questions about the African continent splitting in two, as written by Lucia Perez Diaz for The Conversation Africa.

After heavy rains and seismic activities on Monday, 19th March, the earth split open, leaving a huge tear that is more than 50 feet deep and more than 50 feet wide weaving through the arable land in Narok County. The large crack, stretching several kilometers, and which continues to grow, caused part of the Nairobi-Narok highway to collapse in south-western Kenya

Kenya Rift Valley, Narok. Courtesy: Daily Nation

The fissures have torn the busy Mai Mahiu-Narok road apart and the Kenyan government has filled that section with rocks and cement to allow vehicles to ply the route.

Rifts are the initial stage of a continental break-up and, if successful, can lead to the formation of a new ocean basin. An example of a place on Earth where this has happened is the South Atlantic ocean, which resulted from the break up of South America and Africa around 138m years ago.

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 southwestern Kenya. This process is accompanied by surface manifestations along the rift valley in the form of volcanism and seismic activity.

Not all of these fractures formed at the same time, but followed a sequence starting in the Afar region in northern Ethiopia at around 30m years ago, and propagating southwards towards Zimbabwe at a mean rate of between 2.5-5cm a year.

Topography of the Rift Valley. James Wood and Alex Guth, Michigan Technological University. Basemap: Space Shuttle radar topography image by NASA

Although most of the time rifting is unnoticeable to us, according to geologists, 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.

The geological process cannot be stopped however, and the East African Rift allows for observation of different stages of rifting along its length.

Eventually, over a period of tens of millions of years, seafloors will spread along the entire length of the rift. The ocean will flood in and, as a result, the African continent will become smaller and there will be a large island in the Indian Ocean composed of parts of Ethiopia and Somalia, including the Horn of Africa.