Heat is continuously flowing outward from Earth’s interior, and the transfer of heat from the core to the mantle causes convection in the mantle. This convection is the primary driving force for the movement of
tectonic plates. At places where convection currents in the mantle are moving upward, new lithosphere forms (at ocean ridges), and the plates move apart (diverge). Where two plates are converging (and the convective flow is
downward), one plate will be subducted (pushed down) into the mantle beneath the other. Many of Earth’s major earthquakes and volcanoes are associated with convergent boundaries.
