makes up the bottom of the world's oceans is Magma from the underlying mantle erupts at the edges, then cools and solidifies to form new ocean crust.plate a process called seafloor spreading and back into the.
the crust + lithosphere earth's crust: crust crust continental crust lithosphere crust continental and oceanic crust mantle asthenosphere mantle lower mantle mantle outer core outer core inner core inner core
Subduction occurs on continental boundaries because oceanic sub floor is denser and heavier than the lighter more buoyant crust. The oceanic crust slides under the continental crust areas usually on a plate boundary. This is in a recycle style mode that constantly is remaking the ocean floor. The oldest rocks on the ocean bottom are a drop in the geologic time bucket, compared to the rock ages on land.
The oceanic crust slides under the continental crust due to the differences in their densities. The continental crust is more felsic (contains more silica) which makes it lighter than the oceanic crust which is more mafic (containes more fe and mg). Because the process of subduction is very slow, gravitational forces have a stronger effect on the more dense oceanic crust, causing this crust to be pulled under the continental crust and down into the mantle.
Continental crust is made of granite. Oceanic crust is made of basalt.
Crust and the upper mantle
Oceanic crust.
From the colliding plates called Plate Tectonics which two continental crust/ two oceanic crust/ continental - oceanic crust will collide then the one that is denser will go in the mantle that we called Subduction after that happens the one continental crust will go upward until volcano will formed that is called Upthrust Faulting. It is either the crust will form mountain or volcano but it depends upon the pressure in the mantle that makes the landform to have a Magma Chamber
The oceanic crust is denser
Continental: granite oceanic: basalt
The correct answers are - B. Where oceanic crust meets continental crust, and C. Earthquakes.Subduction zones appear only on places where a crust of lower density (oceanic crust) meets a crust of higher density (continental crust).On the places where the oceanic crust meets the continental crust, the oceanic crust goes beneath the continental crust, this makes changes and readjustments in the inner part of the crust, and plus there's significant pressure from the mantle layer from beneath, so earthquakes are a very common occurrence.Check all that apply. A. Broad river deltas B. Where oceanic crust meets continental crust C. Earthquakes D. Two continents collide
Inner core: 2450 km thick Outer core: 2300 km thick Lower mantle: 2500 km thick Upper Mantle: 400 km thick continental crust: 30-70 km thick Oceanic Crust: 6 km thick
The oceanic crust is the part of the earth's crust that is below the ocean. The rock that makes up the oceanic crust is about 200 million years old.