The movement of the Earth's tectonic plates is primarily driven by the heat from the Earth's interior. This heat causes convection currents in the mantle, which is the semi-fluid layer beneath the Earth's crust. The key mechanisms that contribute to this movement include:
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Convection Currents: Heat from the Earth's core causes the mantle material to heat up, become less dense, and rise. As it reaches the upper mantle, it cools down, becomes denser, and sinks back down. This cycle creates convection currents that can push and pull tectonic plates.
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Slab Pull: This occurs when an oceanic plate subducts beneath a continental plate or another oceanic plate. The weight of the cold, dense slab of the oceanic plate pulls the rest of the plate along with it into the mantle.
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Ridge Push: At mid-ocean ridges, where new crust is formed as magma rises to the surface, the newly formed crust is elevated compared to the older, denser crust away from the ridge. This elevation exerts a force that helps push the tectonic plates apart.
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Gravitational Forces: The gravitational forces acting on the plates also play a role, particularly in the context of slab pull and ridge push dynamics.
These processes combined create the movement of tectonic plates, leading to geological phenomena such as earthquakes, volcanic activity, and the formation of mountain ranges.
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