1. Geology 4th edition by Chernicoff & Whitney
Chapter 18
Deserts and the Work of Winds
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2. Copyright © 2007 Pearson Prentice Hall, Inc.
What Is a Desert?
A region that receives very little annual rainfall and is generally sparsely vegetated
A region where the aridity index (ratio of potential evaporation to annual precipitation) is greater than 4.0
Figure 18-2
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Deserts of the World
Figure 18-4
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Types of Deserts
Subtropical
Rain-shadow (orographic)
Continental interior
Cold-ocean current
Polar
Figure 18-3
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Types of Deserts
Subtropical
Rain-shadow (orographic)
Continental interior
Cold-ocean current
Polar
Figure 18-5
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Types of Deserts
Subtropical
Rain-shadow (orographic)
Continental interior
Cold-ocean current
Polar
Figure 18-4
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Types of Deserts
Subtropical
Rain-shadow (orographic)
Continental interior
Cold-ocean current
Polar
Figure 18-6
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Types of Deserts
Subtropical
Rain-shadow (orographic)
Continental interior
Cold-ocean current
Polar
Figure 17-25
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9. Weathering in Deserts Primarily mechanical weathering Desert varnish
Figure 5-8
Figure 18-8
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Desert Processes
Stream erosion
Stream deposition
Wind erosion
Wind deposition
Figure 18-10
Figure 18-1
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11. Stream Erosion in Deserts
Arroyos & canyons
Pediments
Inselbergs
Figure 18-9
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12. Stream Erosion in Deserts Inselberg formation
Figure 18-11
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13. Stream Deposition in Deserts
Alluvial fans
Playa
Figure 18-9
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14. Stream Deposition in Deserts Playa deposition
Figure 18-12
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15. The Work of Winds How winds work
Figure 18-14
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16. The Work of Winds How winds work
Figure 18-15
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17. Wind Erosion in Deserts
Deflation
Blowouts
Deflation basins
Abrasion
Figure 18-16
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18. Wind Erosion in Deserts
Deflation
Abrasion
Balanced rocks
Ventifacts
Yardangs
Figure 18-17
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19. Wind Erosion in Deserts
Deflation
Abrasion
Balanced rocks
Ventifacts
Yardangs
Figure 18-18
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20. Wind Erosion in Deserts
Deflation
Abrasion
Balanced rocks
Ventifacts
Yardangs
Figure 18-19
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21. Wind Transport in Deserts
Bed load
Rolling
Saltation
Suspended load
Figure 18-20
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22. Wind Transport in Deserts
Highlight 18-2
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23. Wind Deposition in Deserts Bed-load deposition - Sand dunes
Figure 18-23
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24. Sand Dunes Dune formation
Figure 18-22
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25. Sand Dunes Dune migration
Figure 18-25
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26. Sand Dunes Dune migration
Figure 18-26
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Sand Dunes Dune shapes
Transverse dunes
Longitudinal dunes
Barchan dunes
Parabolic dunes
Star dunes
Figure 18-28
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Sand Dunes Dune shapes
Transverse dunes
Longitudinal dunes
Barchan dunes
Parabolic dunes
Star dunes
Figure 18-28
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29. Copyright © 2007 Pearson Prentice Hall, Inc.
Sand Dunes Dune shapes
Transverse dunes
Longitudinal dunes
Barchan dunes
Parabolic dunes
Star dunes
Figure 18-28
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30. Copyright © 2007 Pearson Prentice Hall, Inc.
Sand Dunes Dune shapes
Transverse dunes
Longitudinal dunes
Barchan dunes
Parabolic dunes
Star dunes
Figure 18-28
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31. Copyright © 2007 Pearson Prentice Hall, Inc.
Sand Dunes Dune shapes
Transverse dunes
Longitudinal dunes
Barchan dunes
Parabolic dunes
Star dunes
Figure 18-28
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32. Wind Deposition in Deserts Suspended-load deposition - Loess
Figure and 18-30
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33. Wind Deposition in Deserts Suspended-load deposition - Desert pavement
Figure 18-32
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34. Reconstructing Paleowind Direction
Figure 18-33
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35. Copyright © 2007 Pearson Prentice Hall, Inc.
Desertification The invasion of desert conditions into formerly non-desert areas
Figure 18-34
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36. Desertification Natural processes
Figure 18-36
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37. Desertification Human induced
Figure 18-37
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38. Desertification Reversing desertification
Figure 18-38
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39. Extraterrestrial Wind Action Wind features on Mars
Figures and 18-40
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