EROSION AND DEPOSITION
Remember that weathering is the process that breaks down rock and other
substances at Earth’s surface. After weathering occurs, erosion comes in.
Erosion is the process by which natural forces move weathered rock and soil
(called sediment) from one place to another. A landslide is an example of erosion –
one that happens very fast! A more common example of erosion is water carrying
soil and gravel down a driveway after it rains.
What are these natural forces that move weathered rock and soil, you ask?
Wind
Water
Waves
Glaciers
Deposition is the process by which sediment settles out of the water or wind that
is carrying it and is deposited in a new area. Deposition changes the shape of the
land.
You may have seen a child who picked up several toys and then carried them across
a room and put them down. This child was acting something like an agent of erosion
and deposition.
Weathering, erosion, and deposition act together in a cycle that wears down
and builds up Earth’s surfaces.
Consider the following analogy:
The construction worker is like weathering because he is breaking up the rock.
The moving dump truck is like erosion because it is carrying the rock away.
The dumping dump truck is like deposition because it is depositing the rock in a new
place.
Weathering
Erosion
Deposition
Questions:
1. Define Erosion
2. Give one example of erosion.
3. Define Sediment
4. What are the four forces that cause erosion?
5. Define Deposition
6-8. Label the following as WEATHERING, EROSION or DEPOSITION
_____________ A glacier picks up the pieces of rock and moves them downhill.
_____________ The pieces of rock are dropped off 6 miles from the mountain.
_____________ Freezing and thawing breaks a mountain into smaller pieces.
_____________ The sand is deposited in El Paso.
_____________ Pebbles are being worn down into sand in the Nevada.
_____________ Wind carries the sand.
_____________ Earthworms break up the soil in your garden.
_____________ The soil ends up in the street.
_____________ The rain carries pieces of the soil down your sidewalk.