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The convection in the Weddell Sea is mostly associated with polynya. According to Akitomo et al. (1995), Arnold L. Gordon was the first to find the remnant of deep convection near the Maud Rise in 1977. This deep convection was probably accompanied by a large polynya which had been appearing in the central Weddell Sea every winter during 1974 ...
The idea is that Earth's most outer layer, known as the lithosphere, that is made up of the crust and mantle is divided into extensive plates of rock. [8] [26] These plates sit on top of partially molten layer of rock known as the asthenosphere and move relative to each other due to convection between the asthenosphere and lithosphere. [26]
Mantle convection is the slow creeping motion of Earth's rocky mantle caused by convection currents carrying heat from the interior of the Earth to the surface. [33] It is one of 3 driving forces that causes tectonic plates to move around the Earth's surface.
In 1947, a team of scientists led by Maurice Ewing confirmed the existence of a rise in the central Atlantic Ocean, and found that the floor of the seabed beneath the sediments was chemically and physically different from continental crust. [54] [55] As oceanographers continued to bathymeter the ocean basins, a system of mid-oceanic ridges was ...
The important step Hess made was that convection currents would be the driving force in this process, arriving at the same conclusions as Holmes had decades before with the only difference that the thinning of the ocean crust was performed using Heezen's mechanism of spreading along the ridges.
In 1960, Hess made his single most important contribution, which is regarded as part of the major advance in geologic science of the 20th century. In a widely circulated report to the Office of Naval Research , he advanced the theory, now generally accepted, that the Earth's crust moved laterally away from long, volcanically active oceanic ridges .
Scientists believe they’ve discovered an ancient ocean floor comprising a new layer between Earth’s mantle and core.
Beginning in 1947 research provided new evidence about the ocean floor, and in 1960 Bruce C. Heezen published the concept of mid-ocean ridges. Soon after this, Robert S. Dietz and Harry H. Hess proposed that the oceanic crust forms as the seafloor spreads apart along mid-ocean ridges in seafloor spreading. [38]