Evidence for Plate Tectonics

Front

What is the continental drift hypothesis?

Back

The continental drift hypothesis is the theory that continents have moved over geological time and were once joined together in a single landmass called Pangaea.

Front

What evidence did Wegener use to support his hypothesis?

Back

Wegener noted that the continental coastlines appear to fit together like puzzle pieces, suggesting they were once connected.

Front

What are tectonic plates?

Back

Tectonic plates are large sections of Earth's lithosphere that move and interact at their boundaries, causing geological activity.

Front

What is a divergent plate boundary?

Back

A divergent plate boundary is where two tectonic plates move apart from each other, often resulting in the formation of new oceanic crust.

Front

What is a convergent plate boundary?

Back

A convergent plate boundary is where two tectonic plates collide, leading to subduction or mountain formation.

Front

What is a transform plate boundary?

Back

A transform plate boundary is where two tectonic plates slide past each other horizontally, causing earthquakes.

Front

How do magnetic reversal patterns support plate tectonics?

Back

Symmetrical magnetic reversal patterns on either side of a mid-ocean ridge indicate that new oceanic crust is being formed and pushed apart.

Front

What is the significance of glacial sediment deposits in supporting plate tectonics?

Back

Deposits of glacial sediment found on opposite sides of an ocean suggest that continents were once connected and have since drifted apart.

Front

Why can't we feel tectonic plates moving?

Back

Tectonic plates move very slowly, on average only a few centimeters per year, which is not perceptible to humans.

Front

What is the age relationship between rocks near a mid-ocean ridge?

Back

Rocks closer to a mid-ocean ridge are younger than those further away, as new crust is formed at the ridge.