1. Mechanical Weathering
What is weathering?
Mechanical and chemical processes that change objects on Earth’s surface over time. Weathering occurs slowly but the rate of weathering varies depending on the weathering agent.
Mechanical Weathering
When physical processes naturally break rock into smaller pieces over time.
Chemical Weathering changes the object chemically over time. Chemical reactions occur during chemical weathering.

2. Examples of Mechanical Weathering
Ice Wedging
Abrasion
Plants
animals

3. Examples of chemical weathering
Acidification
Oxidation

4. What is the difference between weathering and erosion?
Erosion is the movement of Earth’s sediment
from one location to another. The effects of weathering are often followed by erosion.
Which example below is weathering and erosion?
The constant pounding of waves on the shoreline causing rock to turn to sand.______________
The wind blowing the sand to make dunes._____

5. Do Now: Write mechanical or chemical weathering next to each example.
Wave action against the shore.__________
A rusty nail__________________________
Cement cracks in a driveway.__________
Pot holes on a highway._______________
Plant roots growing into a driveway.______
Acidic rain causing pitting of a metal lamp post.__________________

6. Do Now:
How do you think weathering and erosion will shape the coastline of Long Island in the next 100 years?

7. What is Deposition?
Deposition is the laying down(setteling) of eroded sediment.
Often happens at river basins, mountain valleys, ocean bottoms and along coasts.
How are erosion and deposition related?
What factors effect the rate of erosion?

8. Sediment sorting by size
Poorly sorted sediment has a wide range of sizes
Moderately sorted sediment has a small range of sizes
Well sorted sediment has particles all the same size
How would you classify the sediment below?

9. Do Now: Observe the diagram of sediment below.
Label each as well sorted, moderately sorted and poorly sorted.
Explain why you believe each is grouped as such.
Which best characterizes the sand at Smith Point?