The Work of Wind and Deserts - The Changing Earth: Exploring Geology and Evolution - page 404

Review Questions

1. The primary process by which bed load is transported is
a. _____ suspension;
b. _____ abrasion;
c. _____ saltation;
d. _____ precipitation;
e. _____ answers a and c.
2. The Coriolis effect causes wind to be defl ected
a. _____ to the right in the Northern Hemisphere and
to the left in the Southern Hemisphere;
b. _____ to the left in the Northern Hemisphere and to
the right in the Southern Hemisphere;
c. _____ only to the left in both hemispheres;
d. _____ only to the right in both hemispheres;
e. _____ not at all.
3. The dominant form of weathering in deserts is ______,
and the soils are ______.
a. _____ mechanical, thick;
b. _____ mechanical, thin;
c. _____ mechanical, limited;
d. _____ chemical, thick;
e. _____ chemical, thin.
4. The major agent of erosion in deserts today is______,
while during the Pleistocene Epoch, it was______.
a. _____ wind, running water;
b. _____ wind, wind;
c. _____ running water, wind;
d. _____ running water, running water;
e. _____ wind, glaciers.
5. Which of the following is a crescent-shaped dune
whose tips point downwind?
a. _____ barchan;
b. _____ longitudinal;
c. _____ parabolic;
d. _____ transverse;
e. _____ barchanoid.
6. An important source of groundwater for domestic and
agricultural use in arid regions is
a. _____ alluvial fans;
b. _____ playa lakes;
c. _____ bajadas;
d. _____ answers a and b;
e. _____ answers a and c.
7. Where are the thickest and most extensive loess depos-
its in the world?
a. _____ United States;
b. _____ Pampas of Argentina;

c. _____ Belgium;
d. _____ Ukraine;
e. _____ northeast China.
8. Coalescing alluvial fans form
a. _____ buttes;
b. _____ mesas;
c. _____ bajadas;
d. _____ inselbergs;
e. _____ playas.
9. Which of the following is a feature produced by wind
erosion?
a. _____ playa;
b. _____ loess;
c. _____ dune;
d. _____ yardang;
e. _____ none of these.
10. The dry lakebeds found in many deserts are
a. _____ playas;
b. _____ bajadas;
c. _____ inselbergs;
d. _____ pediments;
e. _____ mesas.
11. Is it possible for Mars to have the same type of sand
dunes as Earth? What does that tell us about the cli-
mate and geology of Mars?
12. Using what you now know about deserts, their location,
how they form, and the various landforms found in
them, how can you determine where deserts may have
existed in the past?
13. As noted in the text, some large cities are built on
alluvial fans. What are the advantages and disadvantages
of such an arrangement?
14. Why are so many desert rock formations red?
15. Why are low-latitude deserts so common?
16. If deserts are dry regions in which mechanical weath-
ering predominates, why are so many of their distinc-
tive landforms the result of running water and not of
wind?
17. Why is desert pavement important in a desert
environment?
18. How do dunes form and migrate? Why is dune migra-
tion a problem in some areas?
19. Much of the recent desertifi cation has been greatly ac-
celerated by human activity. Can you think of anything
that can be done to slow the process?
20. What is loess, and why is it important?