1. Weathering
And
Erosion
Weathering
And
Erosion

2. Weathering The breaking down of the Earth’s crust into smaller pieces
Weathering The breaking down of the Earth’s crust into smaller pieces. It is caused by physical, chemical, or biological means.

3. The Different Types of Weathering
Physical Weathering
The Different Types of Weathering
Process by which rocks are broken down into smaller pieces by external conditions.
Types of Physical Weathering
Frost heaving and frost wedging
Plant roots
Friction and impact
Burrowing of animals
Temperature changes

4. Frost Wedging

5. Frost Heaving

6. Frost Action or ice wedging slowly breaks up this sedimentary rock into unusual shapes.

7. Root Pry
The tree is growing in the rock and soon the rock will break apart because of the tree roots.

8. Plant Roots

9. Friction and Repeated Impact

10. Burrowing of Animals

11. Temperature
Temperature can produce mechanical weathering. During the day, the sun’s energy heats a rock’s surface. During the night, the rock’s surface cools. The repeated change from hot to cold may cause the rock to peel or flake layers that are parallel to the rock’s surface. This peeling or flaking is known as exfoliation.

12. Temperature Changes

13. This is a picture of the Half Dome
This is a picture of the Half Dome. The rock is peeling away from the mountain in layers just like an onion. This is exfoliation.

14. These rocks have been blasted by wind and sand causing them to become rounded.
WIND ABRASION

15. Chemical Weathering
The process that breaks down rock through chemical changes.
The agents of chemical weathering
Water
Oxygen
Carbon dioxide
Living organisms
Acid rain

16. Water
Water weathers rock by dissolving it

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

18. This rock is red because of the oxidation of iron in the sediment when the rock was being formed.

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

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

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

22. Acid rain has eaten away this limestone statue.

23. Karst Topography
A type of landscape in rainy regions where there is limestone near the surface, characterized by caves, sinkholes, and disappearing streams.
Created by chemical weathering of limestone

25. Features of Karst: Caves

26. Features of Karst: Disappearing Streams

27. Features of Karst: Sinkholes

28. Erosion
The process by which water, ice, wind or gravity moves fragments of rock and soil.
Erosion loosens & transports sediment formed by weathering.

29. There are many kinds of Erosion.
Here are a few:
Wave Action
Running Water
Landslides
Avalanche
Glaciers
Slump
Creep
Rock Fall
Mud Flow

30. Erosion Moving water & wind cause changes to
existing land forms & create new landforms
such as valleys, plateaus, flood plains,
canyons, caves or dunes

31. Colorado River as it winds its way through the Grand Canyon.

32. Grand Falls,
near Leup,
Arizona

33. Water Erosion
Rivers, streams, and runoff

34. Wave action is when waves hit the rocks and pieces of rock break off.

35. In this picture the running water eroded the sides of this canyon and created the V-shaped valleys.

36. Ice Erosion
Glaciers

37. This is a picture of a glacier which carves out a U-shaped valley where it flows dragging rocks and boulders along the way.

38. Wind Erosion

39. Mass Movements
Landslides, mudslides, slump and creep

40. This is a picture of a landslide. A type of mass wasting.

41. This is a picture of an avalanche
This is a picture of an avalanche. It is similar to a landslide with ice and snow instead of rock.

42. Mudslide

44. This is a diagram of creep
This is a diagram of creep. The hillside slowly slips over many years from temperature or water.

45. Creep

47. In this picture the land has slumped
into the road below.