The Seafloor Spreading Hypothesis

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.

The seafloor spreading hypothesis.

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 1959 he informally presented this hypothesis in a manuscript that was widely circulated. The seafloor spreading hypothesis scientists brought these observations together in the early 1960s to create the seafloor spreadinghypothesis. This evidence was from the investigations of the molten material seafloor drilling radiometric age dating and fossil ages and the magnetic stripes.

Resulted in a ground breaking hypothesis that later would be called seafloor spreading. Magma at the mid ocean ridge creates new seafloor. 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. This evidence however was also used to support the theory of continental drift.

Seafloor spreading helps explain continental drift in the theory of plate tectonics. These plates float atop an underlying rock layer called the asthenosphere. In this hypothesis hot buoyant mantle rises up a mid ocean ridge causing the ridge to rise upward figurebelow. 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.

When oceanic plates diverge tensional stress causes fractures to occur in the lithosphere. Tuzo said that earth s crust or lithosphere was divided into large rigid pieces called plates. In 1962 these ideas. 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.

Hess like wegener ran into resistance because little ocean floor data existed for testing his ideas. Harry hess s hypothesis about seafloor spreading had collected several pieces of evidence to support the theory. 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 and other tectonic activity processes are the result of mantle convection. Seafloor spreading theory of lithospheric evolution that holds that the ocean floors are spreading outward from vast underwater ridges. Seafloor spreading is a geologic process in which tectonic plate s large slabs of earth s lithosphere split apart from each other. In 1965 a canadian geophysicist j.