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What forces drive the process in subduction zones dense pieces of oceanic crust are pulled downward toward the mantle?
Wiki User
∙ 12y ago
gravity
Wiki User
∙ 12y ago
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How are subduction boundaries related to mid-ocean ridges?
The ocean ridges push the old crust into a convergent boundary where it goes into a mantle convection current. The crust then melts in the convection current and is pushed out of the ocean ridge to restart the process again.
Why do composite volcanoes occur at the boundary between oceanic crust and continental crust?
The simple answer: Oceanic crust is more dense than the continental crust, so it goes under as the two plates ram into each other. (This is called subduction) This submerged crust melts into magma, and collects into a large pool under the continental plate where it went under. The pool of magma forces its way up to form a volcano, which sits in front of us and blows when least expected. The whole process takes a very long time. Also, it only happens in convergent boundaries.
Why is the oceanic crust is more active than the continental crust?
This is because the Oceanic Crust is denser and thinner than the Continental Crust and is actively being created by the forces of the magma at different mid-oceanic ridges.
What type of fault occurs when compression forces push one of the fault upward and the other side downward?
thrust A+
Why do volcanoes occur at constructive plate margins and subduction zones?
Because the subducting plate is water saturated oceanic crust, and as it moves down into the mantle it vaporizes the water and forces steam upwards. At the same time, the descending plate causes friction and circulation, leading to pressure-release melting. All of these processes melt the upper mantle to form magma chambers and thus, volcanoes.
Why does subduction occur at some tectonic plate boundaries?
Subduction occurs at convergent plate margins where plates are moving toward each other. Subduction occurs as old oceanic crust becomes thicker and more dense than the upper mantle directly below it. Because it is more dense, it is forced under younger, less dense oceanic crust, or under continental crust, which is always less dense. At these borders of collision, the older and more dense oceanic crust is drawn by gravity downward, into the mantle, where it is slowly melted. The two basic forces responsible are gravity and heat.
Why does oceanic crust slide under continental crust during subduction?
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.
When huge sections of the Earth collide what do they produce?
The huge sections are called tectonic plates. When they collide this is called a convergent boundary. Usually one plate is oceanic and one is continental, and the oceanic plate is forced down in a subduction zone. This forces the continental plate up, giving rise to mountains and often volcanoes.
How does subduction occur?
A plate will subduct for tens to hundreds of millions of years.
Pulling forces form what kind of mountains?
I believe that this question has to do with earth science. When two continental plates come together, a convergent plate boundary, mountains form. If an oceanic plate and a continental plate converge, or come together, a subduction zone is form and the oceanic plate subducts under the continental usually because the oceanic plate is less dense. Hope I kind of answered the question..?
What features of the ocean floor is the deepest?
The ocean basins are the result of tectonic forces and processes. All of the ocean basins were formed from volcanic rock that was released from fissures located at the mid-oceanic ridges. The oldest rocks found in these basins are approximately 200 million years old. This is a lot younger than the oldest continental rocks which have ages greater than 4 billion years. The reason for this discrepancy is simple. Tectonic processes destroy old oceanic rocks! Oceanic rock is returned to the Earth's mantlewhen oceanic crust is subducted. Many of these subduction zones occur at the continental marginswhere oceanic crust meets continental crust. Subduction also creates the ocean's deep trenches.
How are subduction boundaries related to mid-ocean ridges?
The ocean ridges push the old crust into a convergent boundary where it goes into a mantle convection current. The crust then melts in the convection current and is pushed out of the ocean ridge to restart the process again.
How does the rock cycle relates to plate tectonics?
Subduction zones forces rocks to be pulled back down into the mantle where pressure and heat melts and recycles the rocks. Convection in the mantle then forces the magma to the surface at mid ocean ridges and volcanoes.
Why do composite volcanoes occur at the boundary between oceanic crust and continental crust?
The simple answer: Oceanic crust is more dense than the continental crust, so it goes under as the two plates ram into each other. (This is called subduction) This submerged crust melts into magma, and collects into a large pool under the continental plate where it went under. The pool of magma forces its way up to form a volcano, which sits in front of us and blows when least expected. The whole process takes a very long time. Also, it only happens in convergent boundaries.
Why is the oceanic crust is more active than the continental crust?
This is because the Oceanic Crust is denser and thinner than the Continental Crust and is actively being created by the forces of the magma at different mid-oceanic ridges.
When the upward and downward forces on a falling object or changes its direction is called an?
Terminal Velocity.
The relationship between the upward and downward forces exerted on an object in a liquid is called?
buoyancy
