Strong evidence of seafloor spreading and plate tectonics.
Sea floor spreading geography.
The formation of the new crust is due to the rising of the molten material magma from the mantle by convection current.
Seafloor spreading occurs along mid ocean ridges large mountain ranges rising from the ocean floor.
Alfred wegener a german meteorologist born in 1880 developed the idea of continental drift.
The concept of seafloor spreading was put forward by h harry hess an american geologist.
Paleomagnetism led the revival of the continental drift hypothesis and its transformation into theories of sea floor spreading and plate tectonics.
Further he claimed that continents would be pushed aside by the same forces that cause the ocean to grow.
The process of sea floor spreading.
World war ii gave scientists the tools to find the mechanism for continental drift that had eluded wegener.
The rate at which new oceanic lithosphere is added to each tectonic plate on either side of a mid ocean ridge is the spreading half rate and is equal to half of the spreading rate.
The concept of sea floor spreading.
The oceanic crust is composed of rocks that move away from the ridge as new crust is being formed.
The mid ocean ridge is the region where new oceanic crust is created.
The regions that hold the unique record of earth s magnetic field lie along the mid ocean ridges where the sea floor is spreading.
Seafloor spreading theory that oceanic crust forms along submarine mountain zones and spreads out laterally away from them.
He suggested that new sea floor forms at the oceanic ridges and spread outwards from the line of origin.
He suggested that continents moved around the earth like giant rafts.
Fellow scientists at the time thought the theory was ludicrous.
Plate tectonics theory convection currents and sea floor spreading.
This idea played a pivotal role in the development of the theory of plate tectonics which revolutionized geologic thought during the last quarter of the 20th century.
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.