Ch. 3 Plate Tectonics

Front

What is Wegener's hypothesis of continental drift?

Back

The continents were once joined together in a single landmass.

Front

Why is old oceanic crust more dense than new oceanic crust?

Back

Because it is cool.

Front

What forms when continental plates pull apart at a divergent boundary on land?

Back

A rift valley.

Front

Did Alfred Wegener provide evidence from landforms, fossils, and climate in support of his theory of the shrinking Earth?

Back

FALSE.

Front

What occurs where the oceanic crust bends down toward the mantle?

Back

A deep-ocean trench.

Front

What is the theory of plate tectonics?

Back

The theory that Earth's outer shell is divided into several plates that glide over the mantle.

Front

What are tectonic plates?

Back

Large pieces of Earth's lithosphere that move and interact with each other.

Front

What is a convergent boundary?

Back

A tectonic plate boundary where two plates collide.

Front

What is a divergent boundary?

Back

A tectonic plate boundary where two plates move apart.

Front

What is subduction?

Back

The process where one tectonic plate moves under another and sinks into the mantle.