1. Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
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2. Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
Florida Benchmarks
SC.6.N.3.4 Identify the role of models in the context of sixth grade science benchmarks.
SC.6.E.6.1 Describe and give examples of ways in which Earth’s surface is built up and torn down by physical and chemical weathering, erosion, and deposition.
SC.6.E.6.2 Recognize that there are a variety of different landforms on Earth’s surface such as coastlines, dunes, rivers, mountains, glaciers, deltas, and lakes and relate these landforms as they apply to Florida.
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3. Gone with the Wind How can wind shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
Gone with the Wind
How can wind shape Earth?
When wind moves soil, sand, and rock particles, it acts as an agent of erosion.
The grinding and wearing down of rock surfaces by other rock or sand particles is abrasion.
Rocks can become smooth and polished from abrasion.
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4. How can wind shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
How can wind shape Earth?
The removal of fine sediment by wind is called deflation.
Desert pavement results when wind carries soil and fine sediment away from an area, leaving only rocks behind.
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5. How can wind shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
How can wind shape Earth?
How does desert pavement form?
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6. How can wind shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
How can wind shape Earth?
Dunes are mounds of wind-deposited sand common in deserts and along the shores of lakes and oceans.
Dunes usually move in the same direction the wind is blowing.
Wind moves material up the slope and deposits materials on the other side.
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7. How can wind shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
How can wind shape Earth?
Why is the slip face of a dune steeper than the windward slope?
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8. How can wind shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
How can wind shape Earth?
Loess are thick deposits of windblown, fine-grained sediment.
The fine-grained material in loess can be carried far away from the original source and is a valuable resource for forming good soils.
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9. Groovy Glaciers What kinds of ice shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
Groovy Glaciers
What kinds of ice shape Earth?
A glacier is a large mass of moving ice that forms by the compacting of snow by natural forces.
Glaciers move downhill by gravity and cause erosion. As a glacier melts, it deposits the materials it carries.
Glacial drift is the general term for all materials carried and deposited by a glacier.
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10. What kinds of ice shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
What kinds of ice shape Earth?
An alpine glacier is a glacier that forms in a mountainous area.
Glaciers can erode a V-shaped valley caused by a stream into a U-shaped glacial valley.
Cirques, arêtes, horns, and hanging valleys are landforms caused by alpine glaciers.
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11. What kinds of ice shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
What kinds of ice shape Earth?
Continental glaciers are thick sheets of ice that may spread over large areas, including across entire continents.
Continental glaciers flatten and smooth land.
Erratics and drumlins are landforms caused by continental glaciers.
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12. Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
Melting the Ice
During the last Ice Age, an ice dam held back the water of Glacial Lake Missoula.
The dam broke and emptied the entire lake at once, forming huge waterfalls, deep canyons, and tall ripple marks in the land.
Lake Missoula reformed and flooded about 40 more times.
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13. Slippery Slopes How can gravity shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
Slippery Slopes
How can gravity shape Earth?
Gravity influences the movement of water and ice. Gravity also moves rocks and soils down slope.
Mass movement is the shifting of materials due to gravity.
Creep is the extremely slow movement of materials down slope.
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14. How can gravity shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
How can gravity shape Earth?
Rapid mass movements usually happen on steep slopes and are the most destructive.
A rockfall happens when loose rocks fall down a steep slope.
A landslide is the sudden and rapid movement of a large amount of material down slope.
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15. How can gravity shape Earth?
Unit 2 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity
How can gravity shape Earth?
A mudflow is a rapid movement of a large mass of mud.
Mudflows happen when a large amount of water mixes with soil and rock.
Deforestation, volcanic eruptions, and heavy rains can all create mudflows.
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