Rift

Splitting apart Africa: The East African Rift System or Great Rift Valley is one of the best examples of a divergent plate boundary on land in the popular tectonic plate model. It extends almost 6000 km southward from the Afar triple junction between northern Ethiopia and the Arabian Peninsula through eastern to southern Africa, effectively splitting Africa into two separate plates. This results in thin crust with a high flow of heat from the Earth’s interior as well as a series of deep elongated lakes called ribbon lakes, such as Lake Tanganyika and Lake Malawi. The thin crust also results in numerous volcanoes, erupting lava, or molten magma that reaches the Earth’s surface, by a process called decompression melting. The pulling apart of continental plates creates a zone of low pressure that melts the earth’s crust and pulls the magma upwards. The weakened and fault riddled rift zone allows magma to reach the surface and erupt as volcanoes. Photo by Ben Clausen.

Plate tectonics rifting