Tectonic Plates
A tectonic plate is pieces of the lithosphere floating on top of the asthenosphere. The tectonic plates differ in sizes because some have entire continents on them and others have small pieces of a continent on them. Tectonic plates move around the asthenosphere and touch each other. When tectonic plates hit each other it is called a boundary. There are three types of boundaries: convergent, divergent, and transform boundary. A convergent boundary is when two tectonic plates collide. A divergent boundary is when two tectonic plates pull away from each other. Lastly a transform boundary is when tectonic plates slide past each other horizontally. Tectonic plates move because of changes in density in the asthenosphere. These are just some of the amazing things about the Earth that happen everyday.
Pictures from: http://www.learner.org/interactives/dynamicearth/images/new_map.jpg and http://people.hofstra.edu/geotrans/eng/ch9en/conc9en/img/map_world_plate_tectonics.png
Information from: holt science and technology Earth Science text book
Pictures from: http://www.learner.org/interactives/dynamicearth/images/new_map.jpg and http://people.hofstra.edu/geotrans/eng/ch9en/conc9en/img/map_world_plate_tectonics.png
Information from: holt science and technology Earth Science text book