Earth's Crustal Plates. Crustal plates (tectonic plates) are the outer shell of the Earth. Continental crust and oceanic crust are the two main types of plates. Large plates like the North American Plate is considered a continental plate but also contains oceanic crust. Continental crust which contains the interior of the large continents is much older than oceanic plates. Oceanic crust is constantly being created an destroyed around the Earth's surface.