INTRODUCTION Plate tectonics is a recently developed science, and it can be used to explain a lot of phenomena on the Earth, such as earthquakes. There are actually two big fundamental theories of plate tectonics. One of the basic theories is called continental drift, and the other one is the theory of seafloor spreading. The theory of continental drift can not explain the power source of moving continents, so the theory is not complete. The …showed first 75 words of 918 total…

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