1. Weathering, Erosion, and Deposition

2. Weathering
Weathering: rock materials are broken down into smaller pieces such as pebbles, sand, or soil materials

3. Types of Weathering
Mechanical: breaks down rock by physical means without changing its chemical composition
Caused by water, wind, ice, living organisms
Chemical: breaks down rock through chemical reactions
Oxygen, water, salts, and other substances can react with the substances in rock and break, dissolve, or wash away the rock

4. Erosion
Erosion: the movement of weathered rock from one place to another
Gradually occurs over long periods of time by…
ocean waves, rivers, streams, flooding, tsunamis, glaciers, wind, gravity (landslides/mass wasting)
Is considered a destructive process that breaks down Earth’s landforms

5. Look at the following pictures and name what type of erosion is occurring

6. Baffin Island, Nunavut, Canada

7. Waterfall (moving water)

8. Outer Banks, North Carolina

9. Waves driven by ocean winds can cause the sandbars here to shift and change

10. Nevada's Great Basin National Park

11. Wind

12. Rock Formation, Grand Canyon

13. Winds sweeping through the Grand Canyon have eroded this sandstone outcrop into an anvil shape. Wind shapes these fantastical forms by eroding less dense rock, like sandstone, faster than surrounding rock.

14. Alaska's Saint Elias Mountains

15. Bernard Glacier: Glaciers are slow but highly effective shapers of the land, essentially carrying away anything in their path—from soil and rocks to hills and even the sides of mountains.

16. Gulf of St-Lawrence, Québec

17. Waves crashing against the shoreline

18. Deposition
Deposition: the dropping, or depositing, of pieces of rock that have been eroded by water, wind, ice, or gravity
Is considered a constructive process that builds or creates Earth’s landforms
The deposited pieces are called sediment

19. Delta Formation
At the mouth of a river, where the river empties into an ocean or lake, the flowing water slows down and deposits the sediment it is carrying
The sediment can build up to form a delta: a flat fan/triangle shaped piece of land at the river’s mouth

22. Mississippi River Delta

23. Nile River Delta

24. Erosion and Deposition
Both are the result of interactions between Earth’s lithosphere and hydrosphere
Lithosphere: Earth’s rigid outer layer, which is broken into tectonic plates
Hydrosphere: contains all of Earth’s water (including liquid water, ice, and water vapor)
Both are affected by factors like: slope of the land, sediment size, and speed of the water or wind

25. Video Clip
(shoreline erosion)