Erosion is the movement of weathered materials by wind, water, or ice. There are two types of weathering that break down rocks over time: chemical weathering, where rocks are dissolved, and physical weathering, where rocks change shape. Physical weathering occurs through constant freezing and thawing of water in rock joints, while chemical weathering happens as chemicals in rainwater dissolve limestone over a long period.

1. What is erosion?

2. Erosion The movement of weathered materials by wind, water, or ice .

3. Chemical & Physical Weathering Weathering is the process rocks break down. A rock can be broken down in 2 different ways. Chemical weathering is when a rock is dissolved over time. Physical weathering is when the rocks shape is changed.

4. Physical Weathering Constant freezing, and thawing of water penetrates into the rock’s joints

5. Chemical Weathering Chemicals in rainwater dissolve a type of rock called limestone over a long period of time.

6. Oxidation Is the interaction between oxygen molecules and all the different substances they may contact, from metal to living tissue

7. Acid Rain Rain that contains unhealthy amounts of acid is called acid rain. .

8. Alluvial fan Shallow, flat area formed where a deep fast moving stream slows down, widens and deposits its sediment Hint: comes down a mountain

9. Delta Triangle- shaped area at the mouth of a river formed when the river reaches its base level, slows down, and deposits its sediment.

10. Floodplain Broad, flat area surrounding a stream, close enough in elevation so that occasional flooding occurs.

11. Levee A natural bank confining a stream channel

12. Meander A curve or bend in a streambed.

13. Sediment Bits of rock, soil, sand, shells, and remains of organisms.

14. Glacier A large body of moving ice

15. Glacial Till This is the name given to the silt, sand, and rocks.

16. Permeable The rate at which water passes through a material

17. Tidal Action The alternating rise and fall of the ocean’s surface level, caused by the gravitational pull of the Moon and Sun on Earth.

18. Dune A hill of sand that is deposited by the wind