1. Weathering and Erosion
Amole
Spectra of Science
2013

7. Weathering vs. Erosion They work together, but are NOT the same thing
Weathering is like the hammer.
They work together, but are NOT the same thing
Weathering is a process that breaks down rock
Erosion is a process that moves rock
Erosion is like the truck.

8. Types of Weathering
Physical- breaks down rock without changing its chemical composition
Frost wedging
Plant roots
Wind
Water
Chemical-breaks down rock by changing its chemical composition
CO2
Acid Precipitation
Rust

9. Frost Wedging Physical Weathering Water seeps into cracks
Freezes and expands
Pushes rock apart

10. Root Pry Physical Weathering Plant roots grow into rock
Pushes rock apart

11. Wind Abrasion Physical Weathering
Wind carrying sand blasts against these rocks causing them to become rounded

12. Animal Burrows Physical Weathering
Animals create tunnels in rock and sediments breaking them up

13. Water Abrasion Physical Weathering
Running water repeatedly flows over river rocks making them smooth

14. Oxidation of Iron Chemical Weathering
This rock is red because of the oxidation of iron in the sediment when the rock was being formed

15. Acid Precipitation 1908 1969 Chemical Weathering
Released gases from burning fossil fuels react with water in the air to create acids
This acid reacts with limestone to decompose it

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

17. Water
Chemical Weathering
Water can dissolve minerals found in rocks

18. Water
Chemical Weathering
Water can dissolve minerals found in rocks

19. Carbon Dioxide
Chemical Weathering
Reacts with water to form acid

20. Erosion Process by which rock is moved or transported
Deposition- process by which material (sediments) are laid down

21. Water Erosion Water transports and then eventually deposits sediments
Can create deltas, meanders, canyons, and flood plains

22. Meander
S-shaped streams
Wander side to side seeking lowest elevation

23. Delta Occur where rivers meet the ocean
Soil, dirt, sediments deposited at river mouth
Creates new soil-rich land

24. Canyons Large valleys created by rivers or streams over time
Grand Canyon “cut” by Colorado River

25. Wind Erosion Wind picks up and carries sediments to new locations
Creates sand dunes

26. Erosion by Gravity
Gravity causes large masses off rocks and sediments to move from higher locations to lower ones
Ex: avalanches, land slides, and mudslides

27. Erosion by Ice
Glaciers carve U-shaped valleys as they pick up and carry rock fragments along the way

28. Weathering and Erosion QUIZ

29. Frost Wedging Physical Weathering

30. Chemical weathering Rust

31. Root Pry Physical Weathering

32. Water Erosion

33. Erosion by Glacier

34. Erosion by Gravity

35. Erosion by Gravity

36. Physical Weathering- Frost Wedging Erosion- Wind

37. Chemical Weathering- Acid Precipitation
The marble grave marker has been attacked by acidic rain because of the calcite composition. The grave marker on the right, while old, has not been dissolved because of its granite composition

38. Physical Weathering-Tree Pry Erosion by Gravity