Define A Ocean Floor Rift

As the two active rifts continue to open eventually the.

Define a ocean floor rift.

A long narrow valley lying between two normal geologic faults. Stress orientation of its huge neighbor and has adopted the same rift zone orientation from fiske jackson 1972. Ocean definition the vast body of salt water that covers almost three fourths of the earth s surface. Mid ocean ridge definition is an elevated region with a central valley on an ocean floor at the boundary between two diverging tectonic plates where new crust forms from upwelling magma.

Running over 10 000 miles through the atlantic ocean the mid atlantic ridge is the longest mountain range on the planet. Hess theory was that new seafloor is formed when magma is forced upward toward the surface at a mid ocean ridge. Individually ocean ridges are the largest features in ocean basins. Rift valley definition graben.

Oliver and bryan l. 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 where they are created by the process of seafloor spreading rift valleys differ from river valleys and glacial valleys in that they are created by tectonic activity and not the process of erosion. The ocean floor is thus pushed at right angles and in opposite directions away from the crests. Collectively the oceanic ridge system is the most prominent feature on earth s surface after the.

If spreading continues past the incipient stage described above two of the rift arms will open while the third arm stops opening and becomes a failed rift or aulacogen. Rift valleys usually form where the earth s lithosphere has become thin through extension associated with plate tectonic processes. The most popular mechanism for this outward movement is sliding along the volcano ocean floor interface which consists of easily deformable sediments e g. This divergent plate boundary moves apart at a rate of 2 5 cm per year relatively slow for a divergent plate boundary and rises 2 3 km above the ocean floor.

When she inked in and cross hatched the spaces the topographical profile of the north atlantic was evident with mountains and plains and a very obvious mid ocean rift valley indicating continental drift a horrifying concept for geologists to grasp in 1952.