PLATE TECTONICS
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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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