Final answer:
The tectonic plates are large segments of the Earth's crust and upper mantle that move relative to each other. They move due to the heat from the Earth's core which creates convection currents in the molten rock, or magma, beneath the crust. Here, the speed of the plate movement given is 3.1 cm/yr.
Step-by-step explanation:
The term tectonic plates refers to the large segments of the Earth's crust and upper mantle that move relative to each other. There are several tectonic plates covering the Earth's surface, including the Pacific Plate, North American Plate, and others. The movement of these plates is driven by the heat from the Earth's core. This heat creates convection currents in the molten rock, or magma, beneath the crust, causing the tectonic plates above to move. The average speed at which these plates move is typically measured in centimeters per year. In this case, the plate is moving at a speed of 3.1 cm/yr.
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