Deck 19: Water, Wind, and Time: Desert Landforms

Question 1

Owens Lake disappeared because of natural drought cycles.

Answer 1

False

Question 2

In the Basin-and-Range in the Great Basin, horsts are mountain ranges and grabens are valleys.

Answer 2

True

Question 3

By volume, desert lakes are among the largest lakes in the world.

Answer 3

False

Question 4

Badlands are "bad" because they have naturally toxic soils.

Question 5

Antofagasta is located in the driest desert in the world but still experiences occasional flooding.

Question 6

Chemical weathering is more important than physical weathering in deserts.

Question 7

The Green Sahara refers to a period when the Sahara Desert was covered with tropical rainforests.

Question 8

Antofagasta is located in the rain shadow of the Andes.

Question 9

Some sand dunes make an audible sound or "sing" as their particles move in the wind.

Question 10

The Basin-and-Range is an example of a geographic province.

Question 11

Desertification is both natural and anthropogenic conversion of arid lands to desert.

Question 12

A lag deposit forms as small particles such as sand and clay are carried away by the wind, leaving an accumulation of rocks.

Question 13

All badlands are caused by poor landscape practices by people.

Question 14

Dust storms in Owens Lake contain chromium, cadmium, and arsenic.

Question 15

Sand for ergs often comes from former glacial outwash plains, dry lake beds, and river deltas.

Question 16

In recent years Mono Lake's water level has been rising because of improved management of its water resources.

Question 17

The Amu Darya and the Syr Darya rivers once flowed into the Aral Sea.

Question 18

Mesa-and-butte terrain forms only in sedimentary rocks.

Question 19

In part, Antofagasta is arid because of the cold Peru ocean current.

Question 20

As Mono Lake's level dropped, submerged tufa formations became exposed.

Question 21

A petroglyph is a prehistoric rock carving.

Question 22

Eolian erosion is the most important agent of erosion in deserts.

Question 23

The presence of an inselberg indicates that net erosion is occurring.

Question 24

Inselbergs are found in all climates, not just deserts.

Question 25

Sand dunes are found only in deserts.

Question 26

There were more permanent human settlements in the central Sahara about 5,000 years ago than there are today.

Question 27

The Green Sahara refers to a period when large lakes existed in what is now the Sahara Desert.

Question 28

Sand dunes migrate in the direction that the prevailing wind blows.

Question 29

Eolian erosion and deposition sorts particles by their sizes.

Question 30

Eolian means "of or relating to wind."

Question 31

Mesa-and-butte terrain occurs only in deserts.

Question 32

Fossils are common in badlands.

Question 33

Dust in Owens Valley today is about 30% salt.

Question 34

A bornhardt is an inselberg that is derived from crystalline rocks like granite or gneiss.

Question 35

Desert pavement is formed by the erosion of windblown silt and clay.

Question 36

Rock varnish is formed by the activities of bacteria.

Question 37

In the Great Basin Desert, grabens are a form of inselberg.

Question 38

Antofagasta is dry due to the influence of the subpolar low.

Question 39

Mono Lake's water level has dropped due to water diversions.

Question 40

Most deserts receive less than 25 cm (10 in) of precipitation annually.

Question 41

When did water diversions from Owens Lake begin?

A)1900
B)1913
C)1926
D)1953

Question 42

The process of removing sediments and lowering the land surface by wind erosion is called what?

A)a blowout depression
B)desertification
C)deflation
D)desert pavement

Question 43

Through saltation and traction, sand grains move up the ___________ of active sand dunes.

A)bedding planes
B)windward side
C)leeward side
D)slip face

Question 44

In the figure, barchan dunes are shown in which box?

A)A
B)B
C)C
D)D

Question 45

Why are dust storms toxic in the Aral Sea area today?

A)because the dust is naturally toxic
B)because the area is downwind of other polluted areas
C)because of agricultural chemicals
D)because of heavy industrial polluters in the area

Question 46

A __________ is a flat-topped area that is wider than it is tall.

A)mesa
B)butte
C)chimney
D)mesa-and-butte terrain

Question 47

What are dry stream channels called in India?

A)wadis
B)nullahs
C)dongas
D)arroyos

Question 48

Erosion of sandstone creates what?

A)rock varnish
B)quartz sand
C)ventifacts
D)a pedestal rock

Question 49

Where sand completely covers the desert floor, what linear dunes oriented perpendicularly to the prevailing wind direction may form?

A)transverse dunes
B)star dunes
C)barchan dunes
D)longitudinal dunes

Question 50

Approximately when did the Sahara experience wetter conditions?

A)20,000 years ago
B)15,000 years ago
C)7,000 years ago
D)1,000 year ago

Question 51

The Aral Sea streams were diverted mainly to grow what crop?

A)tomatoes
B)corn
C)cotton
D)wheat

Question 52

In deserts, where streams exit a steep canyon a(n) __________ often forms.

A)alluvial fan
B)wadi
C)playa
D)yardang

Question 53

__________ consists of tightly interlocking stones that form a hardened surface on the desert floor.

A)A bajada
B)Desert pavement
C)An inselberg
D)A lag deposit

Question 54

What city diverts water from Mono Lake?

A)Los Angeles
B)Phoenix
C)San Diego
D)Las Vegas

Question 55

A flat, stony plain is called a(n) __________.

A)reg
B)mesa-and-butte terrain
C)inselberg
D)erg

Question 56

In the figure, a lag deposit develops through what process?

A)weathering
B)exfoliation
C)deflation
D)mass wasting

Question 57

The largest erg is what?

A)the Rub' al Khali erg on the Arabian Peninsula
B)the Grand Erg Oriental in Algeria
C)the Erg Iquidi in Algeria
D)the Great Sand Sea in Libya and Egypt

Question 58

Which provides the correct sequence of mesa-and-butte terrain formation?

A)tectonic uplift-sedimentation and lithification-headward erosion
B)headward erosion-sedimentation and lithification-tectonic uplift
C)sedimentation and lithification-tectonic uplift-headward erosion
D)sedimentation and lithification-headward erosion-tectonic uplift

Question 59

"Summer insolation" was highest how many years ago, according to this graph?

A)5,000
B)10,000
C)15,000
D)20,000

Question 60

As a whole, sand dunes migrate in the direction of the ____________.

A)prevailing wind
B)angle of repose
C)windward side
D)dune crest

Question 61

A __________ is a slender spire of rock with a flat top.

A)mesa
B)butte
C)chimney
D)mesa-and-butte terrain

Question 62

Ergs are by definition at least _______ square kilometers in extent.

A)50
B)100
C)125
D)200

Question 63

What scientific evidence is there that indicates the Sahara was wetter?

A)tree ring data
B)ancient beaches and fossils
C)ice core data
D)migration patterns of birds

Question 64

Sand grains move over the crest and down the _____________ on active sand dunes.

A)bedding planes
B)windward side
C)direction of dune migration
D)slip face

Question 65

The Basin-and-Range Province in Nevada is forming because the crust is doing what?

A)lifting up
B)compressing
C)stretching
D)thickening

Question 66

When the dip of sedimentary rocks is less than 30 degrees, a(n) __________ forms.

A)mesa
B)cuesta
C)hogback
D)inselberg

Question 67

Which is not true about the windward side of a sand dune?

A)Sand grains move up the windward side through traction.
B)Sand grains move up the windward side through saltation.
C)Sand ripples often form on the windward side.
D)The windward side settles at the angle of repose.

Question 68

A(n) __________ is a large, weathered outcrop of bedrock surrounded by a flat, alluvium-filled plain.

A)mesa
B)cuesta
C)hogback
D)inselberg

Question 69

Why does the Aral Sea area now experience so many dust storms?

A)because the lake bed is exposed
B)because the wind speed has increased
C)because people have removed vegetation in the region that once anchored the soils
D)because farming activity has increased

Question 70

Since 1994, what has been happening to Mono Lake?

A)Its lake level has continued to fall.
B)Its lake level has remained mostly stable.
C)Its lake level has risen dramatically.
D)It has become saltier.

Question 71

By what year was Owens Lake gone as a result of diversions?

A)1900
B)1913
C)1926
D)1953

Question 72

Referring to the figure, which desert is a rain shadow desert?

A)Gobi Desert
B)Great Victoria Desert
C)Patagonian Desert
D)the Sahara

Question 73

Where sand does not completely cover the desert floor and the prevailing wind consistently comes from one direction, what crescent-shaped dunes can form?

A)barchan dunes
B)star dunes
C)transverse dunes
D)parabolic dunes

Question 74

Why are deserts particularly vulnerable to erosion by water?

A)because they have little or no protective cover of vegetation
B)because the rainfall in the desert is steady and constant
C)because the wind drives the raindrops against the rocks and soil
D)deserts are not particularly vulnerable to erosion by water

Question 75

What crescent-shaped dunes sometimes form where vegetation anchors the sand?

A)barchan dunes
B)transverse dunes
C)parabolic dunes
D)longitudinal dunes

Question 76

Referring to the figure, which desert is the largest?

A)Syrian Desert
B)Arabian Desert
C)Kalahari Desert
D)the Sahara

Question 77

Referring to the figure, which desert is in South America?

A)Gobi Desert
B)Great Victoria Desert
C)Patagonian Desert
D)the Sahara

Question 78

If the prevailing wind shifts direction over the year, what dunes can form?

A)barchan dunes
B)transverse dunes
C)parabolic dunes
D)longitudinal dunes

Question 79

The Aral Sea region has the highest rates of what type of cancer in the world?

A)breast
B)lung
C)pancreatic
D)esophageal

Question 80

Which is not one of the three factors that determine what kind of sand dune will form?

A)the composition of the sand
B)the amount of sand available
C)the strength of the wind
D)whether the wind changes direction over the year