Timescale of Earth's Events

Front

What causes cracks in the Earth's surface?

Back

Earthquake

Front

How often does the surface of the Earth change?

Back

All the time in different places.

Front

What has changed the shape of the Grand Canyon besides water?

Back

Wind

Front

How long did it take to form the Grand Canyon?

Back

Many years

Front

What causes rough rocks to become smooth over many years?

Back

Erosion

Front

What is erosion?

Back

The process by which natural forces like water and wind wear away rocks and soil.

Front

What is an earthquake?

Back

A sudden shaking of the ground caused by the movement of rocks beneath the Earth's surface.

Front

What is a hurricane?

Back

A large storm with strong winds and heavy rain that forms over warm ocean waters.

Front

What is a tornado?

Back

A rapidly rotating column of air that extends from a thunderstorm to the ground.

Front

What is a flood?

Back

An overflow of water that submerges land that is usually dry.