Unit 5 Vocabulary

Front

Asthenosphere

Back

the plastic (malleable) layer within the mantle

Front

Continental Drift

Back

a hypothesis that suggests continents are in constant motion on the surface of Earth

Front

Fossil

Back

the preserved remains or evidence of past living organisms

Front

Lithosphere

Back

the rigid outermost layer of Earth that includes the uppermost mantle and crust

Front

Magnetic Reversal

Back

the process by which Earth’s magnetic field reverses direction

Front

Mid-Ocean Ridge

Back

a mountain range in the middle of an ocean

Front

Plate Tectonics

Back

a theory that Earth’s surface is divided into large plates of rocks that move with respect to each other

Front

Seafloor Spreading

Back

the process where new oceanic crust forms along a mid ocean ridge and older oceanic crust moves away from the ridge

Front

Superposition

Back

the principle that in undisturbed rock layers, the oldest rocks are on the bottom.