1. REVIEW OF WEATHERING AND EROSION

2. WHAT WORD(S) SIMPLY DESCRIBE “WEATHERING”
Breaking down
Remember this is different from erosion
There are two types of weathering:
CHEMICAL AND MECHANICAL

3. CHEMICAL WEATHERING CARBON DIOXIDE DISSOLVE IN WATER ACID RAIN
OXIDATION
ORGANISMS

4. MECHANICAL WEATHERING
PLANTS
ABRASION
ANIMALS
RELEASE OF PRESSURE
TEMPERATURE CHANGE

5. WHAT WORD(S) WOULD SIMPLY DESCRIBE “EROSION”
MOVEMENT
Erosion occurs after weathering
Types of erosion include:
WATER/ICE
WIND
GRAVITY

6. EROSION
WATER
WIND
GRAVITY

7. NEW IMPORTANT TERM…

8. Principle of Uniformitarianism
States that the same processes that operate today operated in the past.
All the types of weathering and erosion we’ve studied that occur today have ALWAYS BEEN OCCURRING since the beginning of the Earth.
A principle is basically a LAW (description of how nature works).

9. Deposition and the Weathering-Erosion-Deposition Cycle (WED Cycle)

10. What is Deposition? START WIND EROSION FINISH DEPOSITION
The process in which sediment is laid down in new locations.
WIND
EROSION
FINISH
START
DEPOSITION

13. What causes Deposition?
All the types of erosion: water, wind, gravity, etc.

14. What is the WED cycle?
The Cycle of Weathering, Erosion, and Deposition that occurs now and has been occurring all around the world at all times.
Because of this cycle, the Earth’s surface has changed greatly over time.
It is what fills in lakes, shortens mountains, made the grand canyon, etc.

15. WED CYCLE
WEATHERING
EROSION
DEPOSITION

16. WED CYCLE
BEATS UP ROCKS
MOVES ROCKS
DROPS ROCKS IN NEW PLACE

17. Here is a section of the Earth’s
surface 100,000 years ago.
There is a mountain and a nice
little lake.

18. Here is the same section after
10,000 years after weathering,
erosion, and deposition have
occurred.

19. Here is the same section
today; weathering, erosion,
and deposition have
occurred and will continue
to occur.

20. Consider this…

21. The Appalachian mountains are the oldest
mountains in the world. They were formed
300 million years ago. The Rocky Mountains
were formed between 65 and 100 million years
ago. The highest part of the Appalachian
Mountains is Mt. Mitchell (in North Carolina) at
6,684 ft. The highest part of The Rocky
Mountains is Mt. Elbert (in Colorado) at
14,440 ft. Can you explain why?