an actively deforming region where two(or more) tectonic plates of fragments of lithosphere move one another and collide.

a boundary along which two tectonic plates move apart,characterized by either a mid-ocean ridge or a continental rift valley.

one of the large,moving pieces into which earths lithosphere is broken and which commonly carries both oceanic and continental crust.

is an opening in earths crust through which molten rock,rock fragments,and hot gases erupt.