Tectonic Plates Large segments of the outer layer of Earth (lithosphere) which drift and float on the asthenosphere

Theory of Plate Tectonics Theory which states that the Earth’s outer layer is made up of rocky plates which drift and move on a thick layer of molten rock

Pangaea A super continent or single land mass existing 200 million years ago made up of the Earth’s current seven continents

Alfred Wegener A German scientist responsible for developing the theory of plate tectonics

Convergent Boundary A zone where tectonic plates collide into each other resulting in mountain formation, earthquakes and volcanic activity

Divergent Boundary A zone where tectonic plates move away from each other forming new crust as the magma rises to the surface.

Transform Boundary Plate boundaries that slide along each other in opposite directions

Subduction The process in which one edge of a tectonic plate is forced beneath the edge of another plate.

Seafloor Spreading A process where new crust on the ocean floor is created through uplifting magma which spreads apart as it cools