Which energy source is thought to drive the lateral motions of Earth's lithospheric plates?

The export of heat from deep in the mantle to the top of the asthenosphere is thought to drive the lateral motions of earth’s lithospheric plates. In geology, mantle is a layer that is inside a terrestrial planet. These terrestrial planets include Venus, marks, Earth, and Mercury.

The earth’s mantle is a layer that lies between the outer core and the earth’s crust. The thickness of the earth’s mantle s estimated to be around 2886 kilometers. Even though it is solid, it behaves as a highly viscous fluid in terms of geological time. The mantle makes up around 15% of the entire volume of Earth.