Tectonic Plates

 

The crust of our planet is cracked into seven large and many other smaller slabs of rock called plates. As they move (only centimeters per year), and depending on the direction of that movement, they collide, forming deep ocean trenches, mountains, volcanoes, and generating earthquakes.

As you can see, some of the plates contain continents and others are mostly under the ocean. The type of crust that underlies the continents is called continental crust, while the type found under the oceans is called oceanic crust. Continental crust is thicker — about 35 to 70 km thick — and usually older than oceanic crust, which is only 7 to 10 km thick.

 

 

This site shows how the plates move:

http://www.learner.org/interactives/dynamicearth/plate.html

 

Major tectonic plates Antarctic Plate African Plate Eurasian Plate Indo-Australian Plate (on certain occasions, this plate is subcategorized into Indian Plate and Australian Plate) South American Plate North American Plate Pacific Plate

Minor plates Caribbean Plate Arabian Plate Cocos Plate Juan de Fuca Plate Philippine Sea Plate Nazca Plate Scotia Plate