How are mid-ocean ridges and deep-ocean trenches related to plate tectonics?

The simple answer is that mid-ocean ridges are formed at the locations where new oceanic crust is forming at the surface under the ocean (or in the case of Iceland, actually at the surface of land). Deep-ocean trenches are the physical manifestation of places where plates are colliding and one plate is moving under another in the process called ';subduction';.How are mid-ocean ridges and deep-ocean trenches related to plate tectonics?
Plate tectonics is the movement of tectonic plates as a result of convection currents in Earth's mantle. Now, these plates crash against each other creating things such a deep-ocean trenches and mountains/volcanos.





Mid-ocean ridges are where lava/magma is rising from between two plates, creating new sea floor. This is called seafloor spreading. These ridges are found commonly in the middle of oceans. The mid-Atlantic ridge is actually the longest mountain range in the world- it's a mid ocean ridge. Also, the deepest point in the world, Challenger Deep, which had been only visited once, is in the mid-Atlantic ridge.





Mid-ocean ridges and ocean trenches are results of plate tectonics and plate movement.How are mid-ocean ridges and deep-ocean trenches related to plate tectonics?
the mid-Atlantic ridge are two plate boundaries the left side is the north America plate and the right side is in-do-Europa plate they both make mountains on both sides of the Atlantic.because the to plates are moving away from each other,and deep ocean trenches are faults that are on the ocean bed that are caused by undersea earthquakes, it also may mean that the two plate boundaries are pulling the trenches apart.
They occur at the boundary between two tectonic plates.


When the Pacific Plate encounters the Philippine Plate, because it is older and more dense than the younger Philippine, it subducts below and results in the formation of a deep ocean trench. The Marianas Trench is 36,000 feet below sea level - the deepest known region of the world's oceans. Take note of the ocean floor near the infamous ';Ring of Fire.';





';Mid-Ocean Ridges are places where the Earth's tectonic plates are gradually moving apart, and as they do, magma rises up to fill the gap, sometimes leading to submarine volcanic eruptions. This shallow magma provides a heat source that creates many seafloor hot springs along the ridges which transport heat and chemicals into the ocean. ';





';The global mid-ocean ridge system is the largest single volcanic feature on the Earth, encircling it like the seams of a baseball. Here the Earth鈥檚 crust is spreading, creating new ocean floor and literally renewing the surface of our planet. Older crust is recycled back into the mantle elsewhere on the globe, typically where plates collide. The mid-ocean ridge consists of thousands of individual volcanoes or volcanic ridge segments which periodically erupt.';


The ridges are built by this upwelling of lava.








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utarch couldn't have explained it any better