This is a photo of EARS.
EARS is one of the oldest and best defined rifts. It is located in the Afar region of Ethiopia and is usually referred to as the Ethiopian Rift. To the south, there are a series of rifts including the western branch, the Lake Albert Rift, or Albertine Rift (which contains the East African Great Lakes), and an eastern branch that roughly bisects Kenya north-south on a line slightly west of Nairobi. These two branches have been termed the East African Rift. The two EAR branches are often grouped with the Ethiopian Rift to form EARS. The complete rift system therefore extends 1000's of km in Africa alone and several 1000s more if the Red Sea and Gulf of Aden are included. There are also many grabens that have rift like character and are clearly associated geologically with the major rifts.
2. How did these rifts form?
One popular theory states that the EARS rift was casued by elevated heat flow from the mantle of the Earth ( Asthenosphere) creating a pair of bulges in central Kenya and the Afar region. As these bulges form, they stretch and crack the outer brittle crust into many normal faults forming the classic horst and graben structure of rift valleys.
3. Explain why the East African Rift System has "two branches" the western and the eastern branch.
These two branches are supposedly following old sutures between ancient continental masses that collided long ago to form the African craton. The split around the Lake Victoria region occured due to the presence of a small core of ancient metamorphic rock, the Tanzania craton, that was too hard for the rift to tear through. The rift instead had to flank it making the two branches what they are today (Nearly Parallel).
Refer to the pictures above to see where the branches are located.
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