1. Erosion

2. Preview Questions: What force causes sediment movement down a slope?
What might cause a landslide?

3. Erosion
Erosion is the process by which natural forces move weathered rock and soil from one place to another.
The material moved by erosion is called sediment.
Gravity moves sediments downhill. Gravity causes mass movement.

4. Agents of Erosion
Gravity
Wind
Running water
Glaciers
Waves

5. Mass Movement Three types of mass movement are: Landslides Mudflows
Slump
Creep

6. Landslides The most destructive type of mass movement.
Rock and soil slide quickly down a steep slope.

7. Mudflows
Rapid downhill movement of a mixture of water, rock, and soil.

8. Slump Mass of rock or soil suddenly slips down a slope.
The material slumps down in one large mass.

9. Creep
The very slow downhill movement of rock and soil.

10. Questions: What is creep? Sketch a drawing of it.
What is the difference between a landslide and a slump?
3. A fence runs across a steep hillside. The fence is tilted downhill and forms a curve rather than a straight line. What can you infer happened to the fence?