East African Rift Valley Flashcards
What is the East African Rift valley a product of?
The East African Rift System is a much larger landscape and is the product of the ongoing creation of a divergent plate boundary.
How is the East African Rift valley formed?
Combination of two key factors:
● The constructive/divergent plates: African and Arabian.
● And the magma plume beneath the plates.
The plume pushed up the land creating bulges and cracks allowing flood basalts to rise through fissures and add to the gradient and create long mountain ranges.
As a result of the divergent plates a small section of land in between these plates breaks away and sinks leaving faults which are filled and covered by lava (flood basalts). Horsts and Grabens are therefore formed.
What is the landscape like?
Two broadly parallel rifts that extend for over 4000km from the Red Sea to Mozambique, with the fault scarps reaching heights of 600m while its width varies between 10 and 50km (A2 Edexcel Geography).
Graben and horst in the East African Rift valley.
The areas of crust that have dropped are known as graben, with the central block of the rift valley being called a horst.
How is the Great Glen and the East African Rift valley different?
Both resulted in valleys, Great Glen is a valley that has been eroded along the fault line as it was a line of weakness whereas the East African rift valley is a much wider and longer valley with horst and graben.
The direction of plate movement at plate boundaries also leads to distinctive landscapes.
Divergent movement lead to the formation of a rift valley.
Convergent movement lead to the formation of mountain ranges.
What other landforms make up the landscape?
Lake Tanganyika is the 2nd deepest lake in the world
Mt Kenya and Mt Kilimanjaro two tallest mountains (composite volcanoes) in Africa (5200m and 5900m)
