Why Is Africa Ripping Apart? Seismic Scan May Tell

Arrays of sensors stretching across more than 1,500 miles in Africa are now probing the giant crack in the Earth located there — a fissure linked with human evolution — to discover why and how continents get ripped apart.

Over the course of millions of years, Earth's continents break up as they are slowly torn apart by the planet's tectonic forces. All the ocean basins on the Earth started as continental rifts, such as the Rio Grande rift in North America and Asia's Baikal rift in Siberia.

The giant rift in Eastern Africa was born when Arabia and Africa began pulling away from each other about 26 million to 29 million years ago. Although this rift has grown less than 1 inch (2.54 centimeters) per year, the dramatic results include the formation and ongoing spread of the Red Sea, as well as the East African Rift Valley, the landscape that might have been home to the first humans.   LifeScience