Changing the Earth: Erosion

Lesson Plan - Get It!

Audio:

The earth is a beautiful place, filled with many different land forms like mountains and canyons.

All of these incredible landforms have been changed over the course of time. Think about the landforms around your home or learning space. A landform is a naturally-occurring formation on the earth's surface.

For example, mountains and hills are landforms. All the landforms around the world have been changed by weathering.

In the previous lesson, found under Related Lessons in the right-hand sidebar, you learned all about weathering.

• What are two types of weathering that affect the earth's surface?

^{Image by Etan J. Tal, via Wikimedia Commons, is licensed under the CC BY 3.0 license.}

• Did you remember that weathering occurs when certain types of weather break down soil and rocks physically?

Great! Some examples of weathering are:

• a river flowing through a canyon wears down the sides of the canyon as it flows
• water seeping into the cracks of rocks and freezing, causing the rock to break
• glaciers moving across the surface of the earth wear away the surface of the earth
• wind causing rocks to break apart, and making soil move from one location to another

Weathering constantly affects the earth around you.

• Did you know weathering causes the earth's soil and rocks to erode?

Erosionoccurs when rocks and soil are moved to different locations by water, ice, and wind. Any time you think of the word erosion, picture rocks and soil moving from one place to another. Erosion is all about the movement of rocks and soil.

^{Image by El Guanche, via Wikimedia Commons, is licensed under the CC BY 2.0 license.}

Take a look at the example below.

• Can you see where the soil and rock have been moved?
• What do you think caused the soil and rock to be removed from this area? .

This picture shows erosion caused by moving water. When an area floods and a small stream forms, this stream moves the soil and rocks from one area to another. Once the stream has dried up, a path is left showing where the stream once was. This path will eventually lead to where the soil and rock were deposited.

Sand dunes are affected by erosion. When the wind blows sand from one area to another, it creates large piles of sand called sand dunes. The sand dune you can see standing tall in the back will eventually be transported to another area in the desert through the process of erosion.

Now that you've seen some samples of erosion, before moving on to the Got It? section, say aloud what the word erosion means.