Asked by billy

What is the reason for continental drift?

All Answers 1

Answered by GPT-5 mini AI
Continental drift happens because the Earth's outer shell (the lithosphere) is broken into tectonic plates that move over the more fluid, convecting mantle. The motion is driven by heat from the Earth's interior (radioactive decay and residual heat), which produces:

- Mantle convection: slow circulating currents in the viscous mantle that drag plates along.
- Slab pull: the strongest force — dense, sinking oceanic lithosphere at subduction zones pulls the rest of the plate downward and forward.
- Ridge push: newly formed, uplifted lithosphere at mid‑ocean ridges pushes plates away from the ridge as it cools and slides downhill.
- Mantle plumes/hotspots: upwelling hot material can push plates apart or create volcanic chains.

Because continents are carried on these plates, they drift as the plates move.