The
East African Rift is part of the larger
Great Rift Valley. It is a continental
rift zone that appears to be a developing
divergent tectonic plate boundary. The rift is a narrow zone in which the
African Plate is in the process of splitting into two new plates called the Nubian and Somalian subplates or protoplates. It runs from the
Afar Triple Junction in the
Afar Depression southward through eastern Africa. It is believed to run offshore of the coast of Mozambique along the Kerimba and Lacerda rifts or grabens, terminating in the
Andrew Bain Fracture Zone complex, where it is believed to have its junction with the
Southwest Indian Ridge.
The East African Rift is unusual in that most of the world's active rifts are found in oceanic crust, and mostly beneath the seas. Besides the much smaller Baikal Rift Zone in eastern Russia and the remote, ice sheet-covered West Antarctic Rift, it is the only other example of actively rifting continental crust on Earth.
The East African Rift consists of two main branches called the Eastern Rift Valley and the Western Rift Valley. These result from the actions of numerous normal (dip-slip) faults which are typical of all tectonic rift zones.
Volcanic activity
The East African Rift zone includes a number of active as well as dormant volcanoes. These include
Mount Kilimanjaro,
Mount Kenya,
Mount Karisimbi,
Mount Nyiragongo,
Mount Meru and
Mount Elgon as well as the
Crater Highlands in
Tanzania. The
Ol Doinyo Lengai volcano remains active, and is currently the only
natrocarbonatite volcano in the world.
References