Sentences with phrase «oceanic crust formed»

Not exact matches

Mars has been viewed as an almost entirely basaltic planet, with igneous rocks that are dark and relatively dense, similar to those forming the Earth's oceanic crust, Wiens noted.

The Andes were formed by tectonic activity whereby earth is uplifted as one plate (oceanic crust) subducts under another plate (continental crust).

Generally speaking, there are two types of crust on Earth: a lighter continental crust that is rich in silicon and constitutes the dry land above sea level, and a denser oceanic crust where water gathers in the form of large oceans.

If the melt erupts quickly, it forms basalt, which makes up the crust beneath the oceans on Earth; but there are still questions about how continental crust, which is more buoyant than oceanic crust, is formed.

Magma from the mantle forms oceanic crust when it rises from the mantle to the surface at spreading centers and cools into the rock that forms the very bottom of the seafloor.

And the oceanic crust has what appears to be a thick underplating of rock formed when magma that was working its way toward the surface became trapped under the crust and cooled — very much like the processes that occur under the Hawaiian Islands.

These islands are so - called «hot - spots» with lava formed from hot mantle plumes that up - well beneath the oceanic crust.

So yes, Rapa Nui sits way out in the ass end of nowhere, atop a seamount that has formed via the Easter hotspot, an upwelling of magma below the oceanic crust that has generated a range of undersea mountains (the Nazca Ridge) as the Nazca Plate drifted above it....

«Our findings suggest that the primordial crust involved in forming our craton was actually more than 4.2 billion years old and similar in composition to oceanic crust, which is very different from continental crust,» O'Neil said.

Beginning about 50 million years ago (and continuing to the present day), the drift of the continental plates has caused the continents of India and Eurasia to collide, pushing up oceanic crust from the bottom of the sea to form the Himalayan mountain chain and the Tibetian plateau.

izen says (I am just quoting one of his letters to nature that he quoted to me) The circulation of seawater through newly formed ocean crust at mid-ocean ridge spreading centres is important in the oceanic heat and chemical budgets.