GEOLOGY

Detailed explanation-1: -A tectonic plate (also called lithospheric plate) is a massive, irregularly shaped slab of solid rock, generally composed of both continental and oceanic lithosphere. Plate size can vary greatly, from a few hundred to thousands of kilometers across; the Pacific and Antarctic Plates are among the largest.

Detailed explanation-2: -Most tectonic plates are composed of both oceanic and continental crust. The Pacific Plate, however, is made up of mostly oceanic crust. Oceanic crust, which is basaltic, is thinner than continental crust. Continental crust, which granitic, is more buoyant than oceanic crust.

Detailed explanation-3: -The fact that the plates include both crustal material and lithospheric mantle material makes it possible for a single plate to be made up of both oceanic and continental crust. For example, the North American Plate includes most of North America, plus half of the northern Atlantic Ocean.

Detailed explanation-4: -Continental and oceanic crust can both be part of the same plate. For example, the North American plate has continental crust (essentially the land area of North America) at its core; this is surrounded on most sides by oceanic crust. A geographic “continent” does not equal a plate.

Detailed explanation-5: -Continental plates have a lower density than Oceanic plates. Granite and recycled materials are much thinner than the ocean plates’ thick basalt layers. Oceanic plates occupy about 71% of the Earth’s surface. Continental plates make up 29% of the Earth’s surface.