EARTH SCIENCE
TECTONICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the earth’s crust moves around but is never destroyed
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old crust is destroyed into the mantle and new crust is formed over time
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old crust is broken down into sand
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all of the above
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Detailed explanation-1: -In the ocean, tectonic processes continuously create and destroy oceanic crust. New crust is created at mid-ocean ridges and moves away from them over millions of years. Old crust is destroyed when it reaches seafloor trenches.
Detailed explanation-2: -Plates occasionally collide and fuse, or they can break apart to form new ones. When the latter plates break apart, a plume of hot rock can rise from deep within the Earth’s interior, which can cause massive volcanic activity on the surface.
Detailed explanation-3: -The correct answer is option (d) Earth’s crust is divided into several large plates that do not move relative to each other. The crust may be a little shell outside the planet, accounting for fewer than 1 Chronicles of the surface.
Detailed explanation-4: -Just as oceanic crust is formed at mid-ocean ridges, it is destroyed in subduction zones. Subduction is the important geologic process in which a tectonic plate made of dense lithospheric material melts or falls below a plate made of less-dense lithosphere at a convergent plate boundary.