Plate tectonics

Although it may be hard to imagine, Earth's crust is constantly shifting. The crust is made up of many regions called tectonic plates that cover the planet. Throughout history, these plates have collided, moved apart, and slid past one another, resulting in the mountain ranges, islands, and ocean floors of today. The plates' awesome destructive power is evident in violent earthquakes and erupting volcanoes. By studying plate tectonics, from massive fault lines to the Ring of Fire, geologists have been able to map the growth and shrinkage of the oceans and accurately predict certain natural disasters.