1. Weathering and Erosion

2. Weathering
The breakdown of the materials of Earth’s crust into smaller pieces.

3. The Agents of Weathering
Ice
Plant roots
Friction and impact
Burrowing of animals
Temperature changes
Water
Oxygen
Carbon dioxide
Living organisms
Acid rain

4. Frost Wedging (Ice)

5. Plant Roots

6. Burrowing of Animals

7. Temperature Changes

8. Water
Water weathers rock by dissolving it

9. Oxygen
Iron combines with oxygen in the presence of water in a processes called oxidation
The product of oxidation is rust

10. Carbon Dioxide CO2 dissolves in rain water and creates carbonic acid
Carbonic acid easily weathers limestone and marble

11. Living Organisms
Lichens that grow on rocks produce weak acids that chemically weather rock

12. Acid Rain
Compounds from burning coal, oil and gas react chemically with water forming acids.
Acid rain causes very rapid chemical weathering

13. Erosion
The process by which water, ice, wind or gravity moves fragments of rock and soil.

14. Water Erosion
Rivers, streams, and runoff

15. Ice Erosion
Glaciers

16. Wind Erosion