External Forces of Change Weathering & Erosion
Weathering breaks down rocks on Earth’s surface into smaller pieces Erosion wears away Earth’s surface (wind, glaciers, moving water), and then carries materials away 1. Explain the difference between weathering & erosion.
Physical- breaks rock into smaller pieces Water freezes in crack, ice splits rock 2. Explain the difference b/w physical & chemical weathering; give example.
Chemical- Δs the actual chemical make-up of the rock Water + CO2 destruction of limestone 2. Explain the difference b/w physical & chemical weathering; give example.
Acidic chemicals from pollution (factories, cars, etc) combine w/ precipitation Eats away at buildings, kills fish/plants, etc. 3. What causes acid rain?
Movement of dust, sand, soil from one place to another Benefits: Mineral-rich soil is deposited creating fertile soil Drawbacks: Good soil can be carried away leaving land barren 4. What is wind erosion? 5. Benefits & drawbacks?
Fertile, yellow-gray soil carried by wind throughout the Yellow River leaving the land great for farming 6. Define LOESS.
7. How can glaciers cause erosion? Slowly move downhill p.u. soil/rocks destroy forests, carve u- valleys, alter river course, wear down mtns.
Large piles of debris/rocks left behind by glaciers Form long ridges of land or create dams that form glacial lakes 8. What are moraines?
9. Describe the difference b/w sheet glaciers and mtn. glaciers. Sheet: flat, broad sheets of ice (Greenland, Antarctica) Can break off to form icebergs Mtn: found in high mts. (Rockies) Move downhill creating valleys
10. How does water cause erosion? Fast-moving water cuts into land, wears away soil/rock creates sediment which grinds away other rocks Waves erode cliffs, beaches, etc. Bill Nye
Water Erosion Bryce Canyon, Utah
Grand Canyon, Arizona Water Erosion, maybe some wind as well
Glacial Erosion Glacier National Park, Montana
Chemical Weathering Bronze turning green
Physical Weathering Breaking of Tombstones