1. Erosion and Deposition
Mass Movement
Goals:
1) Understand what processes wear down the Earth’s surface.
2) Distinguish between the different types of mass movement.

2. Erosion
The process by which natural forces move rocks and soil from one place to another.
On Earth water is the primary agent of erosion

3. Deposition
Occurs where agents of erosion lay down sediment (sand, soil, rocks etc.) to make new landforms
Erosion and Deposition work together to build up and wear down the land over and over again.

4. Mass Movement
Gravity is the force that moves rock and other material downhill.
There are several types of mass movement – moving materials like dirt, rocks and sand down hill.

5. Landslides Are the most destructive kind of mass movement
Occurs when rock and soil move quickly down a steep slope

6. Landslides

7. Landslides

8. Mudflows A rapid movement of a mixture of water, rock and soil.
Water may make up 60% of flow.
Often occur after heavy rains in dry regions

9. Mudflows

10. Mudflows

11. Slump
A mass of rocks and soil slip down hill together in one large piece.
Often looks like someone took a bottom piece out from under the slope

12. Slump

13. Creep Very slow downhill movement of rock and soil
Movement can create weird angles and tilt objects like telephone poles

14. Creep

15. Mass Movement The downhill movement of eroded material.
Water and gravity are major factors in erosion
Question:
Why would a landslide be more likely on a steep slope than a gentle slope?