Unit 1 Vocab Earth Science Unit

Continental crust Rocky material that makes up continents; less dense than material of oceanic crust

Formed where two sections of Earth’s crust are colliding Convergent boundary Formed where two sections of Earth’s crust are colliding

Forms where lithosphere plates are moving away from each other Divergent boundary Forms where lithosphere plates are moving away from each other

Mid-ocean ridge Undersea mountain range that forms where two parts of Earth’s crust are pushing apart. (Divergent plate boundary)

Oceanic crust Earth’s outer crust that lies beneath the oceans, denser than the continental crust

The place where two lithosphere plates meet Plate boundary The place where two lithosphere plates meet

Sea-floor spreading Theory that magma from Earth’s mantle rises to the surface at mid-ocean ranges and cools to form new seafloor, slowly pushing away from the ridge

Subduction zone The process in which one lithosphere plate slides under another; occurs at converging plate boundaries

Tectonic plate One of the pieces of Earth’s rocky crust that rests and moves on the semi-liquid mantle

Theory of plate tectonics Describes plate movement and how movement affects Earth’s geologic features

Transform boundary Boundary between two lithospheric plates where the plates are sliding past each other