a long, undersea mountain chain that has a steep, narrow valley at its center

the process by which new oceanic lithosphere forms as magma rises to earth's surface and solidifies at a mid-ocean ridge

the study of the alignment of magnetic minerals in rock

the theory that explains how large pieces of the lithosphere move and change shape

the solid, outer layer of Earth that consists of the crust and upper part of the mantle

the solid, plastic layer of the mantle beneath the lithosphere

the boundary between tectonic plates that are moving away from each other

the boundary between tectonic plates that are colliding

the boundary between tectonic plates that are sliding past each other horizontally

the process by which Earth's crust breaks apart

a piece of lithosphere that has a unique geologic history and that may part of a larger piece of lithosphere

the process by which supercontinents form and break apart over millions of years

the supercontinent that formed 300 million years ago and that began to break apart around 250 million years ago

the single, large ocean that covered Earth's surface during the time the supercontinent Pangaea existed