Continental Drift

A theory that explains how continents move over time due to the movement of tectonic plates.

Convection currents in the Earth's mantle.

Basalt.

Oceanic crust is more dense than continental crust.

Continental crust and oceanic crust.

Convection.

The process by which new oceanic crust is formed at mid-ocean ridges and older crust is pushed away.

The discovery of seafloor spreading in the Atlantic Ocean.

A major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur.

The process where one tectonic plate moves under another and is forced into the mantle.