Front

Alfred Wegner proposed that all continents were once a supercontinent called ______________.

Back

Pangea

Front

Wegner's hypothesis of _____________ suggests continents are in constant motion on Earth's surface.

Back

continental drift

Front

Mountain ranges in the ocean are called _____________.

Back

mid-ocean ridge

Front

New volcanic crust moves from the ridge.

Back

seafloor spreading

Front

State where magnetized objects, like compass needles, point north.

Back

normal polarity

Front

Magnetic field reversal occurs during _____________.

Back

magnetic reversal

Front

State where magnetized objects reverse direction & orient south.

Back

reversed polarity

Front

Theory that Earth's surface consists of moving rigid rock slabs.

Back

plate tectonics

Front

Cold & rigid outermost rock layer: ___________

Back

lithosphere

Front

Forms when two plates separate and move apart.

Back

Divergent plate boundary