What is it?
Plate tectonics is a theory derived from Alfred Wegner’s 1915 continental drift theory. This theory attempted to explain the strange puzzle-like fit between some of the coastlines of the continents. He proposed that the Earth was made up of several large plates that actually float on the lithosphere. The lithosphere is a layer of molten rock under the earth’s crust. Convection currents are believed to be the driving force behind these movements. A convection current is a “wave” of heat that causes movement. Where the plates’ boundaries are is where there is high seismic activity, such as volcanoes, earthquakes, and mountain formation.
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