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tectonic plates


a boundary where earth's tectonic plates move toward each other. This causes a collision or subduction. This will result in the formation of volcanoes and mountain ranges.

divergent boundary

a plate boundary where two plates move away from each other

transform boundary

a plate boundary where two plates move past each other in opposite directions

plate tectonic theory

the branch of geology studying the folding and faulting of the earth's crust


the outer layer of the Earth


the layer of the earth between the crust and the core


the central part of the Earth


the solid part of the earth consisting of the crust and outer mantle


the soft layer of the mantle on which the lithosphere floats

continental crust

earths crust made of land

oceanic crust

earths crust located under the ocean


a geological process in which one edge of a crustal plate is forced sideways and downward into the mantle below another plate


a crack in the earth's crust resulting from the displacement of one side with respect to the other

rift valley

A deep valley that forms where two plates move apart.


depression formed at a subduction zone

seafloor spreading

The process that creates new sea floor as plates move away from each other at the mid-ocean ridges

mid-oceanic ridge

The longest mountain range in the world; all along the center of the Atlantic Ocean; formed by active volcanoes through sea floor spreading

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