East African Rift Valley
Introduction
East African Rift Valley is one of the most extensive rifts on the Earth 's surface; the valley is about 6,400 kilometers long, averages 48 to 64 kilometers wide and has a depth from a few hundred to several thousand meters. The huge, brittle tectonic plates that make up Earth 's crust normally move only a few centimeters per year, not fast enough to be noticeable in a human lifetime. However, in the East African Rift Valley, this tectonic motion is happening with remarkable speed. The East African Rift valley is an example of an active divergent rift, one of the few areas on Earth where a continent is being actively separated (rifted) by the ongoing forces of plate tectonics.
East Africa Rift System (EARS)
The East African rift system is widely recognized as the classical example of a continental rift system, which is part of the Afro Arabian rift system that extends from the Red Sea to Mozambique in the south.
The rift is assumed to mark the incipient plate boundary between the
Somali and Nubian micro-plates and linked to the Afar- Red Sea- Gulf of Aden rift systems (Figure 1). As the rift extends from the Ethiopian segment southwards it splits at about 5°N into the Eastern and Western branches. The two branches of the rift skirts around the Tanzania craton and formed within the Late Proterozoic belts adjacent to the margins of the craton. However, the Eastern Branch that comprises the Afar,
Ethiopian, Turkana and Kenya rifts is older and relatively more volcanically active than the western branch that comprises Albert, Kivu,
Tanganyika, Rukwa and Malawi rifts. The SW branch comprises
Luangwa-Kariba-Okavango rifts.
FIGURE 1: Structural map showing the East
African Rift System
(Modified from Atekwana et al., 2004)
The rift valleys are a system of normal faults bordering a 40-60 km wide trough, funneling out toward north in the Afar region. The Kenya Rift diverges into splays towards north (Turkana) and south Tanzania
East African Rift Valley is one of the most extensive rifts on the Earth 's surface; the valley is about 6,400 kilometers long, averages 48 to 64 kilometers wide and has a depth from a few hundred to several thousand meters. The huge, brittle tectonic plates that make up Earth 's crust normally move only a few centimeters per year, not fast enough to be noticeable in a human lifetime. However, in the East African Rift Valley, this tectonic motion is happening with remarkable speed. The East African Rift valley is an example of an active divergent rift, one of the few areas on Earth where a continent is being actively separated (rifted) by the ongoing forces of plate tectonics.
East Africa Rift System (EARS)
The East African rift system is widely recognized as the classical example of a continental rift system, which is part of the Afro Arabian rift system that extends from the Red Sea to Mozambique in the south.
The rift is assumed to mark the incipient plate boundary between the
Somali and Nubian micro-plates and linked to the Afar- Red Sea- Gulf of Aden rift systems (Figure 1). As the rift extends from the Ethiopian segment southwards it splits at about 5°N into the Eastern and Western branches. The two branches of the rift skirts around the Tanzania craton and formed within the Late Proterozoic belts adjacent to the margins of the craton. However, the Eastern Branch that comprises the Afar,
Ethiopian, Turkana and Kenya rifts is older and relatively more volcanically active than the western branch that comprises Albert, Kivu,
Tanganyika, Rukwa and Malawi rifts. The SW branch comprises
Luangwa-Kariba-Okavango rifts.
FIGURE 1: Structural map showing the East
African Rift System
(Modified from Atekwana et al., 2004)
The rift valleys are a system of normal faults bordering a 40-60 km wide trough, funneling out toward north in the Afar region. The Kenya Rift diverges into splays towards north (Turkana) and south Tanzania
References: 11- WENDY MILLER-EAST AFRICAN RIFT VALLEY PROJECT-GEOLOGY 306-WINTER, 2009 12- China Daily 08/03/2005 page2