Front

What is seafloor spreading?

Back

Seafloor spreading is the process by which new oceanic crust is formed at mid-ocean ridges as tectonic plates move apart.

Front

Where does seafloor spreading begin?

Back

Seafloor spreading begins at the mid-ocean ridge.

Front

What is found at deep-ocean trenches?

Back

Older oceanic crust is found at deep-ocean trenches.

Front

What are magnetic seafloor stripes?

Back

Magnetic seafloor stripes are patterns of magnetic orientation in the ocean floor that provide evidence for seafloor spreading.

Front

What evidence supports the theory of seafloor spreading?

Back

Evidence includes magnetic seafloor stripes and the age of rocks.

Front

What is a mid-ocean ridge?

Back

A mid-ocean ridge is an undersea mountain range formed by the upwelling of magma at divergent tectonic plate boundaries.

Front

What is the asthenosphere?

Back

The asthenosphere is a semi-fluid layer of the Earth's mantle that allows tectonic plates to move.

Front

What is continental drift?

Back

Continental drift is the theory that continents have moved over geological time and were once joined together.

Front

What role do tectonic plates play in seafloor spreading?

Back

Tectonic plates move apart at mid-ocean ridges, allowing magma to rise and create new oceanic crust.

Front

How does age of rocks relate to seafloor spreading?

Back

Rocks closer to mid-ocean ridges are younger, while rocks further away are older, indicating the process of seafloor spreading.