![]() ![]() The East African Rift is described as an active type of rift.An example of a place on Earth where this has happened is the South Atlantic Ocean, which resulted from the breakup of South America and Africa around 138m years ago.Rifts are the initial stage of a continental break-up and, if successful, can lead to the formation of a new ocean basin.This process is accompanied by surface manifestations along the rift valley in the form of volcanism and seismic activity.The crust above Yellowstone hotspot is thinning because of mantle plume).Įventually, it will rupture, leading to the formation of a rift valley. The lithosphere is subject to a horizontal extensional force, and it will stretch, becoming thinner (E.g.Faulting due to divergence creates extensive rift system (fault zones, rift valleys).Both normal and thrust faults (reverse fault) occur during upwarping. During upwarping, a series of faults are created.Rising limbs of the convection currents create a plume that tries to escape to the surface by upwarping the lithosphere (doming the lithosphere upwards).Rift Valley: a linear-shaped lowland (graben) between several highlands (horst) or mountain ranges created by the action of a geologic rift or fault.Plume: a column of magma rising by convection in the earth’s mantle.Upwarp: a broad elevated area of the earth’s surface.New lithosphere is created at the divergent boundary and old lithosphere is destroyed somewhere else at the convergent boundary.The process of formation of a new sea begins with the formation of a divergent boundary.The primeval water bodies evolved to form seas and oceans.Water began to accumulate in the hollows and basins, and the primeval (earliest) water bodies were formed.After the Earth’s surface temperature came down below the boiling point of water, rain began to fall.They were formed due to continuous ‘degassing’ of the Earth’s interior. ![]()
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