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oceanic crust, the outermost layer of Earth’s lithosphere that is found under the oceans and formed at spreading centres on oceanic ridges, which occur at divergent plate boundaries. Oceanic crust is about 6 km (4 miles) thick. It is composed of several layers, not including the overlying sediment.
Hence most oceanic crust is the same thickness (7±1 km). Very slow spreading ridges (<1 cm·yr −1 half-rate) produce thinner crust (4–5 km thick) as the mantle has a chance to cool on upwelling and so it crosses the solidus and melts at lesser depth, thereby producing less melt and thinner crust.
1 Ιαν 2018 · Oceanic crust formed at MOR is primarily basaltic in composition and thin (~3–10 km thick) compared to continental crust that has an average thickness of 35–40 km and a roughly andesitic composition (Taylor and McLennan 1985; Rudnick 1995).
On average, oceanic crust is 6–7 km thick and basaltic in composition as compared to the continental crust which averages 35–40 km thick and has a roughly andesitic composition.
14 Ιαν 2019 · The thickness and velocity structure of unaltered oceanic crust mainly depends on the conditions at the mid-ocean ridge where it was formed (cf. McKenzie & Bickle, 1988). By contrast, the properties of continental crust are the result of a much longer evolution.
12 Δεκ 2016 · Our linear regressions of the seismic data show that average oceanic crust of the Indian and Atlantic oceans is roughly 7.9 km thick at 150 Ma, and has decreased to 4.6 km near the modern ...
1 Ιαν 2023 · Oceanic crust is the outer solid layer of the Earth beneath the oceans. This type of crust is 6–9 km thick, it is essentially basaltic (mafic) in composition and denser of the continental crust.
