Although convection in the mantle has yet to be fully understood, researchers generally agree on the following:
Convective flow in the rocky 2900-kilometer- (1800- mile-) thick mantle—in which warm, buoyant rock rises while cooler, denser material sinks—is the underlying driving force for plate movement.
* Mantle convection and plate tectonics are part of the same system. Subducting oceanic plates drive the cold downward-moving portion of convective flow, while shallow upwelling of hot rock along the oceanic ridge and buoyant mantle plumes are the upward-flowing arms of the convective mechanism.
* Convective flow in the mantle is a major mechanism for transporting heat away from Earth’s interior to the surface, where it is eventually radiated into space.