1. Weathering and Erosion.
By: Mallory, Manoj, and Brandon

2. The two main external forces of change are
Wind & Water

3. Weathering & Erosion The movements of wind and water include
weathering and erosion.

4. Weathering
Weathering is the process of which rocks break down into smaller pieces.

5. Types of weathering
Physical Biological Chemical

6. Physical weathering.
Physical weathering is the breaking down of rocks through direct contact.

8. Chemical weathering
Chemical weathering changes the actual chemical make-up of rocks.

9. Types of chemical weathering
Hydration Solution

10. Hydration
Hydration is when minerals in the rock absorb water and expand, creating stress which causes the disintegration of rocks.

11. Solution
Solution is a process by which minerals in the rocks dissolve directly in water.

12. Erosion
Erosion is the process that picks up and carries away broken off pieces of sediment

13. Types of erosion
Wind Water Glacial

15. Water Erosion Running water carves away the land much like a glacier.

16. Water Erosion The Grand Canyon Mississippi River Delta
The Colorado River carved the walls of the canyon

17. Glacial Erosion Glaciers are huge masses of ice that carve the land.
This is a glacier --

18. Glacial Erosion
An example of a
Glacial valley.