Global tectonics, north-eastern Atlantic. Satellite-based artwork of a close-up of an Earth globe showing the Atlantic part of the North American Plate, one of the seven primary tectonic plates that make up the Earth's crust. Phenomena observed at the plate boundaries (yellow) include earthquakes, volcanic activity, mountain-building, and oceanic trench formation. The movement of the tectonic plates over the millions of years of geologic time drives the creation, destruction and drifting of the continents. The movement of the tectonic plates is thought to be driven by convection currents in the underlying mantle.