Sea-Floor Spreading
What is Sea-floor spreading?
Seafloor spreading is a process of plate tectonics in which new oceanic crust is created as large lumps of the Earth 's crust split apart from each other and magma shafts up to fill the gap.
Who discovered sea-floor spreading?
The man who discovered sea floor spreading was Harry Hess. Harry Hess was a geologist. Part of his mission had been to study the deepest parts of the ocean floor. In 1946 he had discovered that hundreds of flat-topped mountains, perhaps sunken islands, shape the Pacific floor. After much thought, he proposed in 1960 that the movement of the continents was a result of sea-floor spreading. It was possible, he said, that molten magma from beneath the earth 's crust could ooze up between the plates in the Great Global Rift. Also Hess proved Wegener 's basic idea right. The continents are attached to the plates and do not move independently of them. But the plates themselves shift and change shape, carrying the continents along.
How is this done?
The large lumps of rock that make up the Earth’s crust are called tectonic plates. As they slowly move away from each other under the ocean floor, hot magma from the Earth’s mantle rises to the surface. This magma is then cooled by ocean water. The new rock forms a new part of the Earth’s crust. Seafloor spreading occurs along mid-ocean ridges.
What happens to the old crust?
Over time, new oceanic crust thrusts the older crust farther away. New bodies of water and even continents can be shaped through seafloor spreading. The Red Sea, for example, was created through seafloor spreading, as the African plate and the Arabian plate tear away from each other. Today, the northern Sinai Peninsula connects the Middle East with North Africa. Eventually, geologists predict that seafloor spreading will expand the Red Sea so that it will completely separate the two continents.
References:
Seafloor spreading is a process of plate tectonics in which new oceanic crust is created as large lumps of the Earth 's crust split apart from each other and magma shafts up to fill the gap.
Who discovered sea-floor spreading?
The man who discovered sea floor spreading was Harry Hess. Harry Hess was a geologist. Part of his mission had been to study the deepest parts of the ocean floor. In 1946 he had discovered that hundreds of flat-topped mountains, perhaps sunken islands, shape the Pacific floor. After much thought, he proposed in 1960 that the movement of the continents was a result of sea-floor spreading. It was possible, he said, that molten magma from beneath the earth 's crust could ooze up between the plates in the Great Global Rift. Also Hess proved Wegener 's basic idea right. The continents are attached to the plates and do not move independently of them. But the plates themselves shift and change shape, carrying the continents along.
How is this done?
The large lumps of rock that make up the Earth’s crust are called tectonic plates. As they slowly move away from each other under the ocean floor, hot magma from the Earth’s mantle rises to the surface. This magma is then cooled by ocean water. The new rock forms a new part of the Earth’s crust. Seafloor spreading occurs along mid-ocean ridges.
What happens to the old crust?
Over time, new oceanic crust thrusts the older crust farther away. New bodies of water and even continents can be shaped through seafloor spreading. The Red Sea, for example, was created through seafloor spreading, as the African plate and the Arabian plate tear away from each other. Today, the northern Sinai Peninsula connects the Middle East with North Africa. Eventually, geologists predict that seafloor spreading will expand the Red Sea so that it will completely separate the two continents.
References:
References: http://education.nationalgeographic.com/education/encyclopedia/seafloor-spreading/?ar_a=1 http://www.pbs.org/wgbh/aso/databank/entries/do62se.html By: Rakan AlMasri 8A