Twenty-five million years ago, as plate tectonics began to pull apart eastern Africa, the landscape that would eventually be home to the first humans began to take shape. … The East African Rift Valley, as the region is known, formed where the Somalian and Nubian plates are pulling away from the Arabian Plate.
What caused the East African Rift Valley?
Millions of years ago, the Arabian Peninsula was connected to Africa. Seafloor spreading caused the Arabian and African plates to rift apart. The Indian Ocean flooded the rift valley between the continents, creating the Red Sea. … South of the Red Sea Rift lies the massive, complex East African Rift.
How was the rift valley formed in Africa?
Geologists know that the Rift Valley was formed by violent subterranean forces that tore apart the earth’s crust. These forces caused huge chunks of the crust to sink between parallel fault lines and force up molten rock in volcanic eruptions.
How was the East African Rift Zone created?
The East African Rift Valley (EAR) is a developing divergent plate boundary in East Africa. … The Nubian and Somalian plates are also separating from the Arabian plate in the north, thus creating a ‘Y’ shaped rifting system. These plates intersect in the Afar region of Ethiopia at what is known as a ‘triple junction’.
When was the African rift valley formed?
It included what today is called the Lebanese section of the Dead Sea Transform, the Jordan Rift Valley, Red Sea Rift and the East African Rift. These rifts and faults were formed 35 million years ago.
How is a rift valley formed give one example of a rift valley?
A rift valley is formed by the submergence of a big landmass between two high block mountains, e.g. the Rhine river flows through a rift valley in its middle course.
How are rift valleys formed Upsc?
A rift valley is a lowland region that forms where Earth’s tectonic plates move apart, or rift. Rift valleys are found both on land and at the bottom of the ocean and are created by the process of seafloor spreading.
Which process helps in formation of Rift Valley?
Detailed Solution. The correct answer is Faulting. The valley is formed by the rift or faulting. It is a liner-shaped low land between several highlands or mountain ranges created by the action of geologic rift or fault.
What volcanoes have formed in the East African Rift Zone?
The East African Rift Zone includes a number of active and dormant volcanoes, among them: Mount Kilimanjaro, Mount Kenya, Mount Longonot, Menengai Crater, Mount Karisimbi, Mount Nyiragongo, Mount Meru and Mount Elgon, as well as the Crater Highlands in Tanzania.
How are rift valleys formed and what makes the Jordan Rift Valley significant?
The Jordan Rift Valley was formed many millions of years ago in the Miocene epoch (23.8 – 5.3 Myr ago) when the Arabian Plate moved northward and then eastward away from Africa. One million years later, the land between the Mediterranean and the Jordan Rift Valley rose so that the sea water stopped flooding the area.
How are rift valleys and block mountains formed?
Block mountains and rift valleys are associated landform as they are formed by the divergent plate boundaries due to the tensional forces which act on its boundary.
Why is the Rift Valley important to Africa?
The system of rift valleys that characterizes the African continent represents a perfect environment to understand the evolution of mankind; for the important paleoanthropological discoveries in Ethiopia, Kenya, Tanzania, Uganda and Zaire, the African rift valleys are indeed considered the “cradle of mankind”, that is …
What geologic processes are occurring in East Africa’s Great Rift Valley?
The East African rift system is marked by substantial volcanic activity, including lavas erupted from fissures along the rift in the region. Much of the faulting observed in this image cuts through such lavas. Elsewhere along the rift system, individual volcanoes form.
How old is the East African Rift Valley formed?
The rift has been forming for some 30 million years (as Africa and the Arabian Peninsula separated) and has been accompanied by extensive volcanism along parts of its length, producing such massifs as Kilimanjaro and Mount Kenya.
What type of fault is the East African Rift Valley?
Continental rifting requires the existence of extensional forces great enough to break the lithosphere. The East African Rift is described as an active type of rift, in which the source of these stresses lies in the circulation of the underlying mantle.
What occurs early on in the formation of a rift?
Early in the rift formation, streams and rivers flow into the low valleys and long, narrow lakes can be created. Eventually, the widening crust along the boundary may become thin enough that a piece of the continent breaks off, forming a new tectonic plate.