A Rift in Africa | weatherology°
By: Meteorologist Michael Karow
Updated: Jul 21st 2020

A Rift in Africa

There's a place where a continent is literally being ripped apart to form two separate continents and a new sea in-between. Although this entire process will take 5-10 million years, the eastern portion of Africa, known as the East African Rift, is an area being studied with many tools to better understand what is going on geologically, including GPS and satellite-based radar.

The Earth's crust is split into 7 major and 8 smaller minor tectonic plates. These sections of crust encompass land that is both above sea level and also sections of ocean floor. As these tectonic plates move past each other, they also sometimes collide and even split apart, driven by the currents in the more fluid, molten mantle layer deeper in the Earth. It is a rising plume of magma from deep within the mantle that geologists believe is driving the split or rift between Africa's Nubian and Somalian plates.

Using GPS sensors, scientists are able to measure the movement in the tectonic plates down to the millimeter scale. Along with radar systems based on satellites orbiting Earth, geologists now have a better idea of the speed at which Africa's rifting is occurring. They found that the Nubian and Somalian plates are moving apart at a rate of 6-7 mm/year. At this rate, it will take roughly 5-10 million years to form a new sea.

This process has happened before, too. In the same region, the Red Sea and the Gulf of Aden, two long and relatively narrow bodies of water were formed when the Arabian tectonic plate rifted away from the two African plates. It is this long, narrow-style sea that geologists project will form in the future along the East African Rift.

Africa tectonic motion earthquakes Stamps 2018
Map of African earthquakes (circles) and motion of tectonic plates (arrows) - [Stamps et al., 2018]
10 million years Africa future Times India
Projection of what Africa will look like 10 million years in the future - [The Times of India]
Africa rift mantle plume Levin 2005
Cross section of the African rift showing the mantle plume below - [Levin, 2005]