The puzzle pieces of the crust
The crust is broken up into several pieces called tectonic plates
These plates move around because of convection currents (= movement of liquid rock in the mantle, caused by heat of the inner core).
Plate tectonics = The movement of tectonic plates.
Plate boundaries = The places where two plates meet.
So if you thought Earth plates were formed in the
following way, as in the video Ice Age, then you are