The Seafloor Spreading Hypothesis

Mantle convection is the slow churn ing motion of earth s mantle.

The seafloor spreading hypothesis.

Tuzo said that earth s crust or lithosphere was divided into large rigid pieces called plates. Seafloor spreading theory of lithospheric evolution that holds that the ocean floors are spreading outward from vast underwater ridges. This evidence however was also used to support the theory of continental drift. When oceanic plates diverge tensional stress causes fractures to occur in the lithosphere.

Tuzo wilson combined the continental drift and seafloor spreading hypotheses to propose the theory of plate tectonics. The seafloor spreading hypothesis scientists brought these observations together in the early 1960s to create the seafloor spreadinghypothesis. These plates float atop an underlying rock layer called the asthenosphere. Magma at the mid ocean ridge creates new seafloor.

In 1965 a canadian geophysicist j. This evidence was from the investigations of the molten material seafloor drilling radiometric age dating and fossil ages and the magnetic stripes. 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 theory that oceanic crust forms along submarine mountain zones known collectively as the mid ocean ridge system and spreads out laterally away from them.

In this hypothesis hot buoyant mantle rises up a mid ocean ridge causing the ridge to rise upward figurebelow. Seafloor spreading helps explain continental drift in the theory of plate tectonics. Resulted in a ground breaking hypothesis that later would be called seafloor spreading. Seafloor spreading and other tectonic activity processes are the result of mantle convection.

Harry hess s hypothesis about seafloor spreading had collected several pieces of evidence to support the theory. A mystery solved in 1912 when alfred wegener proposed that the continents had once been joined together and had split apart the biggest weakness in his hypothesis was the lack. In 1959 he informally presented this hypothesis in a manuscript that was widely circulated. In 1962 these ideas.

Hess its major tenets gave great support to the theory of continental drift continental drift. First proposed in the early 1960s by the american geologist harry h. Seafloor spreading is a geologic process in which tectonic plate s large slabs of earth s lithosphere split apart from each other. The motivating force for seafloor spreading ridges is tectonic plate slab pull at subduction zones rather than magma pressure although there is typically significant magma activity at spreading ridges.