Sea Floor Spreading For Dummies
For instance the atlantic ocean is believed to be expanding because of its few trenches.
Sea floor spreading for dummies. The motivating force for seafloor spreading ridges is tectonic plate pull rather than magma pressure although there is typically significant magma activity at spreading ridges. The motivating force for seafloor spreading ridges is tectonic plate pull rather than magma pressure although there is typically significant magma activity at spreading ridges. Seafloor spreading theory that oceanic crust forms along submarine mountain zones and spreads out laterally away from them. This seafloor spreading hypothesis had been proposed a few years earlier by harry hess a petrologist at princeton university and robert dietz an oceanographer in the us coast and geodetic survey the federal department that made maps of the oceans and us coastlines.
Seafloor spreading happens at the bottom of an ocean as tectonic plates move apart. Harry hess proposed the seafloor spreading hypothesis in 1960 published in 1962. Seafloor spreading occurs along mid ocean ridges large mountain ranges rising from the ocean floor. This mechanism which is a more accurate version of alfred wegener s original drift of continents that plow through the sea was proposed by harry hess from princeton university in the 1960s this phenomenon is known to be caused by convection currents in the.
Subduction and sea floor spreading are processes that could alter the size and form of the ocean. 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. At ridges in the middle of oceans new oceanic crust is created. Seafloor spreading is a part of the theory of plate tectonics.
Due to this continuous seafloor spreading occurs and makes atlantic ocean floor to be connected to other continental crust making the ocean gets wider over the time. According to hess seafloor was created at mid oceanic ridges by the convection of the earth s mantle pushing and spreading the older crust away from the ridge. The seafloor moves and carries continents with it. Sea floor spreading is the process by which continental drift occurs.
The term spreading of the seafloor was introduced by geophysicist robert s. At ridges in the middle of oceans new oceanic crust is created. The seafloor moves and carries continents with it. Uniformitarianism in geology the doctrine suggesting that earth s geologic processes acted in the same manner and with essentially the same intensity in the past as they do in the present and that such uniformity accounts for all geologic change.
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. Geophysicist frederick john vine and the canadian.