Erosion and deposition are natural processes that occur constantly. This lesson will teach you how erosion and deposition work to change the surface of our earth, then you can test your knowledge with a short quiz.
Pablo the Pebble
Pablo is a tiny pebble who lives in a little patch of grass near a river. Pablo is not well behaved, so he’s always grounded. He is getting really bored of being in the same place all the time, and he often dreams of escaping to the faraway land across the river.
One morning, Pablo wakes up and notices that the wind is blowing a little bit harder than normal. He hears thunder and sees lightning flashing across the sky. Pretty soon, the wind really starts to gust, and big fat raindrops start to fall.All of a sudden, Pablo is lifted off of the ground by a strong wind and whisked into the fast-flowing river.
The water carries him for several minutes until he washes up on the opposite bank. Pablo is in a whole new world. He has just experienced natural processes called erosion and deposition.
What Is Erosion and Deposition?
Pablo’s little adventure is an example of what’s always happening in nature. Erosion is when materials, like soil or rocks, are moved by wind or water. All these materials are called sediments. Deposition is when those sediments are deposited, or dropped off, in a different location.
These processes change the way the surface of the earth looks over time.Erosion and deposition are constantly happening. After all, wind and water can easily cause materials to move to different places. Next time it rains, find a patch of dirt and watch what happens to it when the drops hit. Does the dirt look exactly as it did before, or was it moved in some way? And when it’s windy outside, can you see all of the dust blowing through the air? These are just a couple of examples of erosion and deposition happening all around us.
Now, let’s look at some more specific examples of these natural processes.
Examples of Erosion
As we mentioned, when you see dust blowing or rain moving dirt, you are seeing small examples of erosion. Over longer periods of time, these small movements can lead to some big changes. In deserts, it is easy to see the effects of wind erosion. Deserts don’t get much water, but they do get a lot of wind. Since they consist of mostly sand and rock, the wind causes a lot of erosion. Sand dunes are constantly shifting and moving, and rocks often get changed into unique shapes.
The Grand Canyon is a great example of water erosion. The Grand Canyon was formed over millions of years by the Colorado River, which carved into the ground and eroded the land. The Grand Canyon is now a mile deep in places.
Examples of Deposition
Rivers provide us with a great example of deposition, which is when the materials from erosion are dropped in a new location. Their moving waters pick up sand, dirt, and other sediments and then carry them downstream.
Rivers often turn brown or murky because of all of the materials they carry. When the river reaches its end, it deposits the sediments into lakes or oceans. Pictures taken from above show how the color of the water changes because of all the soil, rocks, and other materials that are being deposited.
Our earth is constantly changing due to erosion and deposition. Wind and water move dirt, rocks, and other materials (erosion) and drop them off in different locations (deposition).
All of these little movements lead to big changes to the surface of the earth.