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Do you know the answers?

What large landform in the western United States

was formed by the movement of water over millions

of years?

Why do the pyramids in

Egypt look like this?

The Grand Canyon was formed by the

Colorado River

Weathering due to sand

and acid rain

Agenda 03 – 04 MAR 15

1.Quiz Review (I have – Who has?)

2.Vocabulary Quiz

3.Weathering and Erosion Notes

4.Weathering Lab

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WEATHERING AND EROSION

Human!

The Natural Bridge

was a sacred site of

the Native American

Monacan Tribe tribe

here in Virginia.

215 feet

tall!

90 feet

across!

Click the pic to watch a video!

Weathering

The breaking down of rocks, soils, and minerals in

the Earth’s crust into smaller pieces

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Weathering

Chemical

Weathering

Physical (Mechanical) Weathering

Physical Weathering

Process by which rocks are broken down into

smaller pieces by external conditions without

changing their chemical composition

Types:

Frost breaking rock (2 kinds!)

Plant roots

Friction and repeated impact

Burrowing of animals

Temperature changes

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Frost Wedging

Water seeps into cracks in the rock and freezes. Freezing water expands, pushing apart the rocks. Repeated cycles will eventually split the rock!

Frost Heaving An upward swelling of soil due to water freezing beneath the surface. This can even make buildings shift upward!

Click the pic to watch a video!

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Plant Roots

(Root Wedging)

Plant roots extend into fractures and begin to grow which causes the fracture to expand. Continued growth and expansion can break the rock!

Friction and

Repeated Impact

Rocks continually scrape or bump into other rocks, breaking smaller pieces off. These smaller pieces continue to bump and scrape against other rocks, eventually wearing away completely.

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Burrowing of Animals

Temperature

Changes

Heating causes rocks to expand. Cooling causes rocks to contract (shrink). When this happens unevenly, rocks can break. Heating can be caused by sunlight or fires!

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Chemical Weathering

The process that breaks down rock through

chemical changes.

Types:

Dissolving by water

Oxygen (Oxidation)

Carbon dioxide

Living organisms (urine) or dead decomposing

Acid rain

Water Water weathers rock by dissolving it.

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Oxygen Oxygen combines with other elements to form new substances. For example, oxygen combines with iron in the presence of water. The product of this oxidation reaction is rust.

Carbon

Dioxide

Carbon dioxide (CO2) dissolves in rain water, forming carbonic acid. Carbonic acid can easily dissolve limestone and marble, causing significant weathering.

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Living & Dead

Organisms

Lichens that grow on rocks produce weak acids that chemically weather rock. Decaying organisms can also produce acids (from bacteria) that are capable of weathering rock.

Acid Rain Compounds from burning coal, oil, and gas react chemically with water forming strong acids. Acid rain causes very rapid chemical weathering.

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Karst Topography

A type of landscape in rainy regions that causes

disappearing streams, caves, and sinkholes

Created by chemical weathering of limestone

Example of Karst: Disappearing Streams

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Example of Karst: Caves

Example of Karst: Sinkholes

Click the pic to watch a video!

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Erosion Movement of rocks and soil

by water, wind, or ice.

Water Erosion

Rivers, streams, and runoff

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Mass Movements

Landslides, mudslides, slump, creep, and debris flow

Click the pic to watch a video! Click the pic to watch a video!

Ice Erosion

Glaciers

Click the pic to watch a video!

Click the pic to watch a video!

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Wind Erosion

Click the pic to watch a video!

1. FOLLOW all directions

2. Work with YOUR group

3. Write down your very BEST answer

4. CLEAN UP your lab station

5. Turn in to the “IN BOX”

6. Becomes homework if not done!

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Websites and Videos from the Presentation

1. http://studyjams.scholastic.com/studyjams/jams/science/rocks-minerals-

landforms/weathering-and-erosion.htm

(Study Jams – Weathering and Erosion)

2. https://www.youtube.com/watch?v=9jzycX380PA

(Foundation Frost Heaving)

3. http://pbskids.org/dragonflytv/show/sinkholes.html

(Sinkholes)

4. http://video.nationalgeographic.com/video/101-videos/landslides

(Landslides 101)

5. https://www.youtube.com/watch?v=_yCnQuILmsM

(Amazing Flash Flood/Debris Flow Southern Utah)

6. https://www.youtube.com/watch?v=njTjfJcAsBg

(Underneath a Glacier Time Lapse)

7. www.discovery.com/tv-shows/frozen-planet/videos/time-lapse-glacier-movement/

(Time Lapse Glacier Movement)

8. http://pbskids.org/dragonflytv/show/sand_dunes.html

(Sand Dunes by Victoria and Alejandra)

9. https://ees.as.uky.edu/sites/default/files/elearning/module07swf.swf

(Weathering and Climate Animation)

Extra material!