Plate Tectonics Theory
The theory of plate tectonics is that the outer rigid layer of the earth (the lithosphere) is divided into a few of dozen "plates" that move around across the earth's surface relative to each other, like ice on a lake.Plate tectonics (from the Late Latin tectonics, from the Greek: τεκτονικός "pertaining to building") is a scientific theory describing the large-scale motion of 7 large plates and the movements of a larger number of smaller plates of the Earth's lithosphere, over the last 100's of millions of years. The theoretical model builds on the concept of continental drift developed during the first few decades of the 20th century. The geoscientific community accepted plate-tectonic theory after seafloor spreading was validated in the late 1950s and early 1960s.
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