1. Weathering

2. Weathering
Weathering is the process by which rocks break down and change
Mechanical
Chemical

3. Mechanical Weathering
Mechanical(Physical) Weathering is the process where rocks break into smaller pieces with no change in their composition
Caused by:
Cold temperatures
Tectonic Processes
Biological Activity

4. Mechanical Weathering
Frost Wedging-The repeated thawing and freezing of water in the cracks of rocks
Water expands when frozen, chips away parts of the rock

5. Frost Wedging Expansion of freezing water in cracks and crevices
Eventually breaking rocks into pieces
Sections of rock that are wedged loose are called talus

6. Unloading
Unloading occurs when igneous rock becomes exposed through uplift and erosion
Exfoliation-Occurs when pieces of the uplifted rock are weathered and chipped away

7. Unloading
The uplift and erosion of rocks overlying igneous rocks because pressure on igneous rocks is reduce
Exfoliation—slabs of outer rock separate and break loose

8. Biological Activity Organisms can cause Mechanical Weathering
Plant roots growing into cracks in rocks
Burrowing animals moving rocks
Decayed animals can produce acids (Chemical Weathering)

9. Chemical Weathering
Chemical Weathering- Rocks undergo changes in their composition
Caused by:
Water
Oxygen
Carbon Dioxide
Acids

10. Hydrolysis/Oxidation
Hydrolysis-The reaction of water with other substances
Oxidation-The reaction of oxygen with other substances

11. Water
Water causes Chemical Weathering by absorbing gases from the atmosphere and ground
CO2 +Water  Carbonic Acid
Dissolves Rocks/Minerals
Stalactites/Stalagmites

12. Statue of liberty
The statue of liberty is made of copper which is generally a brownish color
Has been affected by chemical weathering
Water reacting with the copper
Sulfuric acid formed by pollution (debatable)

13. Differential Weathering
Differential weathering is when rocks weather at different rates
Caused by different mineral compositions
Sedimentary rocks weather more easily than igneous rocks