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How does convection in Earth's mantle contribute to plate movement?

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Convection within the Earth’s mantle is widely considered a primary driver of tectonic plates. This process functions as a thermal system where heat—generated by the decay of radioactive elements—causes mantle material to move in a circular pattern.12

Although the mantle is solid, it flows through solid-state creep, similar to the movement of glaciers, because the material is near its melting temperature. In this system, warm, buoyant material rises while cool, dense material sinks. This convective circulation is believed to propel the plates that sit atop the mantle, though the exact mechanics of how this flow translates into surface movement remain a subject of scientific study.21

Beyond convection, other forces contribute to plate motion:
* Slab pull: Occurs when a dense oceanic plate sinks into a subduction zone, pulling the rest of the plate behind it.12
* Ridge push: A gravitational force where cooling, dense rocks at mid-ocean ridges slide away from the elevated ridge, allowing new magma to rise.12