1. Chapter 3: Erosion and Deposition
Section 1: Changing Earth’s Surface

2. Wearing Down & Building Up
Erosion- the process by which natural forces move weathered rock and soil from one place to another
Deposition- occurs where the agents of erosion deposit, or lay down, sediment

3. Wearing Down & Building Up
Weathering, erosion, and deposition act together in a cycle that wears down and builds up Earth’s surface. This cycle, called the geologic cycle, has continued for billions of years.

4. Mass Movements
gravity- the force that moves rock and other materials downhill
mass movement- any one of several processes that move sediment downhill

5. Mass Movements
The different types of mass movement include landslides, mudflows, slump, and creep.

6. Landslides Occurs when rock and soil slide rapidly down a steep slope
May contain only a small amount of rock and soil
Can be triggered by earthquakes

7. Landslides

8. Landslides

9. Mudflows
The rapid downhill movement of a mixture of water, rock, and soil
Can contain as much as 60% water
Can be triggered by earthquakes

10. Mudflows

11. Mudflows

12. Slump A mass of rock and soil rapidly slips downhill
Moves as one large piece

13. Slump

14. Creep The very slow downhill movement of rock and soil
Can occur on gentle slopes
Can form from the freezing and thawing of water in cracked layers

15. Creep

16. Creep

17. Creep

18. The end.