1. 4.3 Agents of Erosion and Deposition
Unit 4: Weathering, Erosion, Deposition and Landscapes
January 10, 2012
Sanders

2. Unit 4: Weathering, Erosion and Landscapes
Do Now: Define
Abrasion
Deflation
Sorted (deposits)
Striations
Till
Unsorted (deposits)
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

3. Unit 4: Weathering, Erosion and Landscapes
Main Topics
The following are related to Earth’s materials.
Weathering: to break down Earth’s materials
Erosion: to carry away
Deposition: to leave behind
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

4. Unit 4: Weathering, Erosion and Landscapes
Weathering is the break down of Earth’s surface.
Infer:
What type of weathering caused this? 
Notice at right, the material has been weathered and the resulting sediment remains
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

5. Unit 4: Weathering, Erosion and Landscapes
Erosion refers to Earth’s weathered material being taken away.
What is going on in this picture?
At left, a house on the cliff is in immanent danger of falling into the water.
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

6. Unit 4: Weathering, Erosion and Landscapes
Deposition
Deposition refers to eroded material being left behind.
Where is the deposition in this picture?
At right shows material being deposited as the river slows.
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

7. Agents of Erosion & Deposition
In the following, we will look at different agents that erode the earth.
These agents also deposit material in a very specific way.
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

8. Unit 4: Weathering, Erosion and Landscapes
Running Water
Running water pushes particles along a channel.
These particles tumble against each other.
If a stone starts out sharp and angular, what happens?
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

9. Unit 4: Weathering, Erosion and Landscapes
Running Water
When the velocity of the water decreases, particles settle out.
Larger, rounder or more dense particles will settle out first.
A car is buried in mud after flooding in Highland, California.
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

10. Unit 4: Weathering, Erosion and Landscapes
Wind
Wind pushes particles along by having one particle bound into another.
It is sort of like playing pool.
At left is a hoodoo carved by wind in the Black Hills of South Dakota.
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

11. Unit 4: Weathering, Erosion and Landscapes
Wind
Like water, when the velocity wind is diminished, the larger, rounder and more dense particles settle first.
This is called sorted deposition.
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

12. Unit 4: Weathering, Erosion and Landscapes
Glaciers
Glaciers move material in its path like a giant bulldozer.
All loose material gets moved.
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

13. Unit 4: Weathering, Erosion and Landscapes
Glaciers
When glaciers melt, they leave behind piles of unsorted material called moraines.
The soil that got moved is called till.
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

14. Unit 4: Weathering, Erosion and Landscapes
Glacial Moraine
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

15. Unit 4: Weathering, Erosion and Landscapes
Saltation
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

16. Unit 4: Weathering, Erosion and Landscapes
Gravity
Gravity pulls material toward the center of the Earth.
Mud slides
Rock slides
Land slides
Simple Collapse
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes

17. Unit 4: Weathering, Erosion and Landscapes
Gravity
Material at the bottom of the slope is called a talus slope.
This is unsorted deposition.
April 8, 2019
Unit 4: Weathering, Erosion and Landscapes