What role does mantle convection play in plate tectonics?

Mantle convection is a fundamental process that drives the movement of tectonic plates. This occurs due to the heat within the Earth, which causes the mantle's semi-fluid rock to flow in a cyclical pattern. As hot material from the deeper mantle rises towards the surface, it cools and then sinks back down, creating a continuous convection current.

These convection currents exert forces on the overlying tectonic plates, facilitating their movement. This mechanism is crucial because it explains how the plates can slowly drift apart, collide, or slide past each other, leading to the various geological phenomena observed at plate boundaries, such as earthquakes, volcanic activity, and mountain building. Understanding this driving force is key to comprehending the dynamics of plate tectonics and the actions of Earth's lithosphere.