Answer: Convection currents
Step-by-step explanation:
The Earth’s tectonic plates are constantly moving like giant ‘rafts’ on top of the semi-molten mantle below. However, this movement is slow and rates vary from less than 2.5cm /yr to over 15cm/yr. One explanation for the movement of the Earth’s crustal plates is believed to be convection currents which occur in the semi-molten mantle.
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