The East African Rift

When was the East Africa rift formed?

• About 22 milion years ago, in the Miocene era.

• About 4000 million years ago, in the Hadean era.

• About 3100 million years ago, in the Mesoarchean era.

• About 66 million years ago, in the Mesozoic era.

The East African Rift System is formed by...

• three microplates; the Victoria microplate in the north and the Rovuma and Lwandle microplates in the south.

• two microplates; the Lwandle microplate in the north and the Rovume microplate in the south.

• three microplates; the Rovuma and the Lwandle microplates in the north and the Victoria microplate in the south.

• two micropletes; the Rovuma microplate in the north and the Lwandle microplate in the south.

What will happen when the lithosphere is subjected to a horizontal extensional force?

• It will stretch, becoming thinner, leading to the formation of a rift valley

• It will compress, becoming thinner, leading to the formation of a rift valley

• It will stretch, becoming thicker, leading to the formation of a rift valley.

• It will compress, becoming thicker, leading to the formation of a rift valley.

What is the East African Rift responsible for?

• It is responsible for the spreading of the sea floor.

• It is responsible for the destruction of the crust.

• It is responsible for the lateral movement of tectonic plates.

• It is responsible for the creation of mountains and volcanoes

Towards the Afar region, the entire rift valley floor is covered with volcanic rocks.This suggests that, in this area, the lithosphere has thinned almost to the point of complete break up.

What will happen if this succeeds?

• When this happens, a new ocean will begin forming by the solidification of magma in the space created by the broken-up plates.

• When this happens, Africa will expand and it will become 2 times larger than what it already is

• When this happens, the magma will go to the surface and it will form a lot of tall montains.

• When this happens, part of Africa will sink and a ocean will be formed.

What causes the stretching of the lithosphere and potential rupture of the lithosphere?

• Convection currents.

• Violent eruptions.

• The erosion of the lithosphere

• Subduction zones