The movement of the plates creates three types of tectonic boundaries: convergent, where plates move into one another; divergent, where plates move apart; and transform, where plates move sideways ...

St. Helens. Most of the subducting plate continues into the mantle, perhaps to reappear much later at a distant divergent boundary.

All of these processes result from plate tectonics, the movement of enormous chunks of Earth's crust. This movement may be why life exists here ... of rocks. For example, around 3 billion years ...

Four types of plate tectonic activity are demonstrated in this feature. Keep an eye on the map to see where in the world the activity takes place. Also known as spreading boundary, a divergent ...