Sea Floor Spreading E

Their crystals are pulled into alignment by the earth s magnetic field just like a compass needle is pulled towards magnetic north.

Sea floor spreading e.

World war ii gave scientists the tools to find the mechanism for continental drift that had eluded wegener. Seafloor spreading theory that oceanic crust forms along submarine mountain zones and spreads out laterally away from them. These age data also allow the rate of seafloor spreading to be determined and they show that rates. Seafloor spreading definition a process in which new ocean floor is created as molten material from the earth s mantle rises in margins between plates or ridges and spreads out.

Further he claimed that continents would be pushed aside by the same forces that cause the ocean to grow. Most basalt magmas contain abundant molten iron. Once the basalt cools completely into solid rock the. The process of sea floor spreading.

The mid ocean ridge is the region where new oceanic crust is created. The concept of seafloor spreading was put forward by h harry hess an american geologist. Maps and other data gathered during the war allowed scientists to develop the seafloor spreading hypothesis this hypothesis traces oceanic crust from its origin at a mid ocean ridge to its destruction at a deep sea trench and is the mechanism for continental drift. The formation of the new crust is due to the rising of the molten material magma from the mantle by convection current.

As upwelling of magma continues the plates continue to diverge a process known as seafloor spreading samples collected from the ocean floor show that the age of oceanic crust increases with distance from the spreading centre important evidence in favour of this process. Seafloor spreading occurs along mid ocean ridges large mountain ranges rising from the ocean floor. Earlier theories by alfred wegener and alexander du toit of continental drift postulated that. As magma starts to harden into rock iron rich minerals solidify first.

He suggested that new sea floor forms at the oceanic ridges and spread outwards from the line of origin. The mid atlantic ridge for instance separates the north american plate from the eurasian plate and the south american plate from the african plate the east pacific rise is a mid ocean ridge that runs through the eastern pacific ocean and separates the pacific plate from the north american. The oceanic crust is composed of rocks that move away from the ridge as new crust is being formed.