AIM: DO NOW: HW:

AIM: WHAT ARE THE DIFFERENT TYPES OF WEATHERING AIM: WHAT ARE THE DIFFERENT TYPES OF WEATHERING? DO NOW: WHAT IS FOUND IN LIMESTONE THAT CAUSES IT TO REACT EASILY WHEN EXPOSED TO ACID RAIN? (FYI: FLORIDA HAS A FOUNDATION OF LIMESTONE BEDROCK!) HW: WEATHERING WIZARD DUE MONDAY

AIM: QUIZ TODAY DO NOW:TAKE AN ESRT AND CLEAR YOUR DESK HW:

AIM: WHAT IS WEATHERING. DO NOW: 1. DEFINE THE FOLLOWING TERMS: A AIM: WHAT IS WEATHERING? DO NOW: 1. DEFINE THE FOLLOWING TERMS: A. RESISTANT B. WEATHERING HW: WEATHERING WIZARD QUIZ DUE NEXT MONDAY AT 11:59 PM

WHICH MINERAL ON PAGE 16 IS MOST RESISTANT TO WEATHERING???

What do These 3 Things Have in Common?? Statue Grand Canyon Sand Pile

WEATHERING

The physical and chemical processes that change rock. What is Weathering? The physical and chemical processes that change rock.

For weathering to occur, rocks must be exposed to: AIR (atmosphere) WATER (hydrosphere) HUMAN AND/OR ANIMAL ACTIVITIES

Physical Weathering

AIM: WHAT ARE THE DIFFERENT TYPES OF WEATHERING AIM: WHAT ARE THE DIFFERENT TYPES OF WEATHERING? DO NOW: WHAT IS FOUND IN LIMESTONE THAT CAUSES IT TO REACT EASILY WHEN EXPOSED TO ACID RAIN? (FYI: FLORIDA HAS A FOUNDATION OF LIMESTONE BEDROCK!) HW: WEATHERING WIZARD DUE MONDAY

What is Physical weathering? Rocks are broken into smaller pieces without changing the chemical nature of the rock.

Physical Weathering

Types of Physical Weathering

WHY DID THIS HAPPEN??

#1 Frost Action

Water seeps into cracks…. If it freezes it expands….. Slowly breaks (wedges) rock apart Cold and humid climates

Plant Action Tree roots grow into tiny cracks in bedrock….. As the roots grow and expand they break rock apart…. The roots continue to dig deeper and continue the process.

Tree roots can damage pavement

Abrasion

Water causes large angular sediments to tumble into each other…… The angular edges are chipped off….. The size of the rock decreases and it becomes rounded Common in running water “OR” Wind blows sand against bedrock…… Less resistant layers are chipped away and it becomes pitted Wind abrasion in dry climates

ROUNDED PITTED

Humans!!!!

Cute little animals!!!

If you increase the surface area, you will ____________ the rate of weathering

WHAT VISUAL DIFFERENCE DO YOU SEE BETWEEN THE WEATHERED AND UNWEATHERED SHALE?

AIM: WRAP UP WEATHERING AIM: WRAP UP WEATHERING! DO NOW: TAKE OUT WEATHERING NOTES HW: WIZARD DUE MONDAY AT 11:59PM

Chemical Weathering

What is Chemical Weathering? Rocks are broken AND the chemical composition is changed.

Types of Chemical Weathering:

Oxidation – Oxygen from air combines with minerals to form oxides = RUST

Red Sand has been oxidized

Oxidation of Statue of Liberty

Oxidation of Copper When copper oxidizes, it turns a greenish color – called patina.

2. Carbonation Occurs when water containing carbonic acid dissolves minerals

Limestone Cave

What mineral in the limestone causes it to weather so easily What mineral in the limestone causes it to weather so easily? How do you know this?

Stalactites Stalagmites

3. Pollution Oxides of sulfur and nitrogen make rainwater unnaturally acidic. = Acid Rain

4. HYDRATION When water unites chemically with minerals Example: Hornblende + Feldspar + water = CLAY

Dominates in COLD, MOIST climates Physical Weathering: Dominates in COLD, MOIST climates

Dominates in WARM, MOIST climates Chemical Weathering: Dominates in WARM, MOIST climates

What do they both have in common? In general, when there is more MOISTURE, there is more weathering!

What is the end product of weathering? Sediments

The end result of weathering and biologic activity is: SOIL

A B C D Soil Horizons: Bedrock Top Soil - Rotting plants (organic) & finely weathered rock A B Little organic material, partially weathered rock C Partially weathered bedrock D Bedrock

Transported & Residual Soil Types: Transported & Residual

Transported Soils: Carried (by wind, water, humans) from location of parent rock

Most of N.Y. soil is transported by: GLACIERS

Transported Soil

AIM: WRAP UP WEATHERING AIM: WRAP UP WEATHERING! DO NOW: TAKE OUT WEATHERING NOTES HW: WIZARD DUE MONDAY AT 11:59PM

Residual Soil: Remains on top of bedrock from which it was formed.

Therefore, similar composition to bedrock below (parent rock)

What could affect the rate of weathering? (HINT: PAGE 16 OF THE ESRT)

Rock resistance (hardness)

Shale Shale Shale Dolostone Which rock is the most resistant to weathering? Shale Limestone Sandstone Shale Sandstone Shale

Which rock is the least resistant to weathering? Shale Dolostone Which rock is the least resistant to weathering? Shale Limestone Sandstone Shale Sandstone Shale