How does convection in Earth’s mantle help move tectonic plates?

Most scientists believe that tectonic plates move due to convection currents within the Earth’s mantle. Driven by heat from the decay of radioactive elements, this process involves the circulation of mantle material: warm, buoyant material rises while cool, dense material sinks.12

Although the mantle is solid, it flows through solid-state creep—a slow movement similar to that of glaciers—because the material is near its melting temperature. This convective circulation is thought to propel the plates that sit atop the mantle. Specifically, the asthenosphere, a hotter and more fluid zone of the mantle, is believed to lubricate the undersides of these plates, facilitating their movement.213

While mantle convection is a primary driver, other forces such as slab pull (where dense, sinking plates drag the rest of the plate) and ridge push (a gravitational force at spreading ridges) also play significant roles in plate motion.124