The theory of plate tectonics states that the Earth's surface is made up of several large, moving plates. These plates are constantly moving, colliding, and pulling apart due to forces generated by the movement of material in the Earth's mantle. The movement of these plates causes the creation of earthquakes, volcanoes, and mountain ranges as well as the formation of oceanic crust and the reshaping of continents over time. The movement of the plate is caused by the convection currents in the Earth's mantle, which causes the plate to move in a slow and steady way.