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| 1. |
How does an obstacle start the formation of a “dune”?
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| 2. |
Which of the following is TRUE about sand dunes?
[Hint]
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| 3. |
Match the terms for dunes with the appropriate description:
Using the pulldown boxes, match each item on the left to the corresponding item at right.
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| A. layers of sand that are inclined in the direction the wind is blowing, or has blown |
| B. sand in mounds or ridges |
| C. the leeward side of a sand mound or ridge |
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| 4. |
Choose the best description for each label on the photograph of a dune
For each item below, use the pull-down menu to select the letter that labels the correct part of the image.
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| 5. |
Which of the following determines the slope of a slipface of a dune?
[Hint]
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| 6. |
Match the type of dune with the appropriate description:
Using the pulldown boxes, match each item on the left to the corresponding item at right.
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| A. a series of long ridges that are separated by troughs and oriented at right angles to the prevailing wind |
| B. long ridges of sand that form about parallel to the prevailing wind and where sand supplies are moderate |
| C. small, solitary dunes shaped like crescents and with their tips pointing downwind |
| D. isolated hills of sand that exhibit a complex form |
| E. small, solitary dunes shaped like crescents and with their tips pointing upwind, similar in shape to the result of a finger pushed along the sand |
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| 7. |
Identify each of the indicated sand dune types by selecting the correct response.
For each item below, use the pull-down menu to select the letter that labels the correct part of the image.
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| 8. |
Match the type of dune with the description of how and/or where it forms:
Using the pulldown boxes, match each item on the left to the corresponding item at right.
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| A. form where the prevailing wind varies, but stays in the same quadrant of the compass |
| B. form along coasts where vegetation partially covers the sand, and there are strong onshore winds and abundant sand |
| C. form where supplies of sand are limited and the surface is relatively flat and hard, without vegetation |
| D. form where wind is strongly variable, and where sand is plentiful |
| E. form where the prevailing wind is steady, sand is plentiful and vegetation is sparse or absent |
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| 9. |
Which type of dune is this?
How about this?
[Hint]
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| 10. |
Which is NOT a problem caused by the migration of dunes in desert regions?
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| 11. |
Which of the following is NOT a strong factor that influences the form and size of a dune?
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Answer choices in this exercise are randomized and will appear in a different order each time the page is loaded.
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