Quiz 13: Deserts and Wind Action
Geology/Geography/Oceanography/Atmospheric Sciences
Q 1Q 1
A desert is any region which has a dry or arid climate with a low rainfall of less than 25 cm per year.
Free
True False
True
Q 2Q 2
The world's best-known deserts lie in a belt 10-15 degrees centered at latitude of 30 degree (North and South).
Free
True False
True
Free
True False
True
Free
True False
Free
True False
Free
True False
Q 7Q 7
Because sand-sized grains are heavier than silt or clay-sized grains, sand moves close to the ground in a series of short hops called saltation.
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True False
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True False
Q 9Q 9
Most sand dunes are asymmetric in cross section with a gentle slope facing the wind and a steeper slope on the downwind side.
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True False
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True False
Q 11Q 11
Rapid down cutting of desert stream channels produces narrow canyons with vertical walls and flat gravel-strewn floors.
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True False
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True False
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True False
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True False
Q 15Q 15
Since many desert regions have internal drainage, runoff collects on the valley floors as bajadas.
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True False
Q 16Q 16
A transverse dune is a relatively straight, elongated dune oriented parallel to wind direction.
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True False
Q 17Q 17
A pediment is an erosional surface underlain by solid rock, while a bajada is depositional and is underlain by sediment.
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True False
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True False
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True False
Q 20Q 20
Loess is a deposit of wind-blown silt primarily composed of unweathered angular grains of quartz and feldspar.
Free
True False
Q 21Q 21
_____ is the dominant agent of erosion in desert regions.
A) Wind
B) Frost action
C) Running water
D) Actions of the geosphere
E) A combination of all of these.
Free
Multiple Choice
Q 22Q 22
How do deserts form in coastal tropical regions?
A) rain shadow
B) cold ocean currents
C) continental interiors
D) ascending air
E) drought
Free
Multiple Choice
Q 23Q 23
Because of their low rainfall, intermittent stream flow, and dry stream beds, desert lack ____.
A) through-flowing streams
B) vegetation
C) mammals
D) runoff
E) transverse dunes
Free
Multiple Choice
Q 24Q 24
Not all deserts are hot. Descending air near the North and South poles creates ____ deserts.
A) rain shadow
B) cold ocean current
C) sparse
D) polar
E) All deserts are hot.
Free
Multiple Choice
Q 25Q 25
Desert stream channels called ____ are characterized by narrow canyons with vertical walls and flat, gravel-strewn floors.
A) dry streams
B) intermittent channels
C) desert streams
D) stream beds
E) arroyos
Free
Multiple Choice
Q 26Q 26
This area of the desert southwest is characterized by mostly flat-lying beds of sedimentary rock over 1,500 meters above sea level.
A) Colorado Plateau
B) Basin and Range
C) Great Salt Lake
D) Interior Desert
E) Butte province
Free
Multiple Choice
Q 27Q 27
High-speed winds can cause ____, clouds of sand moving rapidly near the land surface.
A) dust clouds
B) sand storms
C) dust devils
D) bajadas
E) deflation
Free
Multiple Choice
Q 28Q 28
A _____ is a depression on the land surface caused by wind erosion which may have a pillar left at the center.
A) mesa
B) loess
C) blowout
D) plateau
E) deflation basin
Free
Multiple Choice
Q 29Q 29
This agent of erosion and deposition is most effective on fine sediment that is dry.
A) flash floods
B) wind
C) frost action
D) desertification
E) dry wash
Free
Multiple Choice
Q 30Q 30
The Colorado Plateau is marked by peculiar, step-like bends in rock layers called ____.
A) hogbacks
B) mesas
C) monoclines
D) cuestas
E) buttes
Free
Multiple Choice
Q 31Q 31
____ is a hard shiny coating of dark iron and manganese oxides and clay minerals that form on rock surfaces in arid environments.
A) Deflation coating
B) Desert armor
C) Ventifact
D) Desert varnish
E) Corona
Free
Multiple Choice
Q 32Q 32
A(n) _____ is a broad gently sloping surface formed by the coalescing of alluvial fans.
A) bajada
B) pediment
C) playa
D) cuesta
E) mesa
Free
Multiple Choice
Q 33Q 33
A(n) ____ is a gently sloping erosional surface, commonly covered with a veneer of gravel, cut into the solid rock of a mountain.
A) bajada
B) pediment
C) cuesta
D) arroyo
E) playa
Free
Multiple Choice
Q 34Q 34
When the desert sun dries a lake, a very flat surface underlain by hard mud-cracked clay called a _______ may form.
A) bajada
B) alluvial fan
C) playa
D) pediment
E) cuesta
Free
Multiple Choice
Q 35Q 35
The removal of clay, silt, and sand particles from a land surface by wind is called _____.
A) blowout
B) saltation
C) scour
D) deflation
E) depression
Free
Multiple Choice
Q 36Q 36
The "horns" in a _______ dune point in a downwind direction.
A) longitudinal
B) symmetrical
C) transverse
D) star
E) barchan
Free
Multiple Choice
Q 37Q 37
The steep downwind face of a sand dune is called the ______.
A) slip face
B) coarsest grains
C) longest dimension
D) gentle slope
E) upwind surface
Free
Multiple Choice
Q 38Q 38
Sand moving over a dune surface by saltation typically forms ___.
A) graded beds
B) ripple marks
C) mud cracks
D) desert pavement
E) tool marks
Free
Multiple Choice
Q 39Q 39
Sand grains found in dunes are commonly _______.
A) poorly sorted and well rounded
B) well sorted and poorly rounded
C) well sorted and well rounded
D) poorly sorted and poorly rounded
E) gravel sized
Free
Multiple Choice
Q 40Q 40
Which of the following would not be a control on desert development?
A) rain shadow
B) great distance from an ocean
C) location near cold ocean currents
D) areas beneath rising air masses
E) climatic belts at 30 north and south latitude
Free
Multiple Choice
Q 41Q 41
U.S. deserts in Nevada and northern Arizona are largely the result of the Sierra Nevada Mountains ____.
A) combined with Coriolis Force
B) deflation
C) volcanism
D) south wind
E) rain shadow
Free
Multiple Choice
Q 42Q 42
Deflation continues to deepen a blowout until it reaches ______.
A) the water table
B) bedrock
C) extent of roots from vegetation
D) sea level
E) There is no lower limit to blowouts.
Free
Multiple Choice
Q 43Q 43
The expansion of deserts into once populated areas is known as ___.
A) sahel formation
B) desertification
C) rain shadow effects
D) deflation
E) desert migration
Free
Multiple Choice
Q 44Q 44
A ______ is a narrow hill of resistant rock with a flat top and very steep sides found in some deserts.
A) butte
B) horn
C) plateau
D) pediment
E) ridge
Free
Multiple Choice
Q 45Q 45
_______ dunes in the Sahara are as high as 200 m and as long as 120 km.
A) Barchans
B) Parabolic
C) Transverse
D) Longitudinal
E) Ventifact
Free
Multiple Choice
Q 46Q 46
Loess deposits in the U.S. Midwest are derived from ____.
A) the Ohio River valley
B) the Rocky Mountains
C) top soil loosened by agriculture
D) the Sahara Desert
E) glacial outwash of the Pleistocene age
Free
Multiple Choice
Q 47Q 47
Most dunes move only ____ per year.
A) 10 to 15 meters
B) 30 to 100 meters
C) 1 to 2 kilometer
D) 5 to 10 kilometers
E) 10 to 100 kilometers
Free
Multiple Choice
Q 48Q 48
Wind-blown sand may sculpt isolated pebbles, cobbles, or boulders into ____.
A) sand dunes
B) ventifacts
C) desert pavement
D) desert varnish
E) desert road
Free
Multiple Choice
Q 49Q 49
A ____ dune is deeply convex and its horns point upwind.
A) bajada
B) parabolic
C) barchan
D) longitudinal
E) transverse
Free
Multiple Choice
Q 50Q 50
Because sand grains are heavier than clay and silt particles, sand grains move close to the ground in a leaping pattern called ______.
A) slipping
B) jumping
C) saltation
D) parabolas
E) blowouts
Free
Multiple Choice
Q 51Q 51
In the United States, large areas of _____ are blanketed with a cover of loess.
A) California
B) Arizona and New Mexico
C) the Rocky Mountains
D) the Midwest
E) Canada
Free
Multiple Choice
Q 52Q 52
_______ has extensive loess deposits up to 100 meters thick.
A) California
B) Canada
C) Brazil
D) Ireland
E) China
Free
Multiple Choice
Q 53Q 53
A large dune type is the _______ (or seif) dune, which forms a ridge parallel to prevailing wind direction.
A) barchan
B) transverse
C) parabolic
D) longitudinal
E) moon
Free
Multiple Choice
Q 54Q 54
_______ is a thin surface layer of closely packed pebbles found in deserts.
A) A pediment
B) Desert pavement
C) A barchan
D) Desert varnish
E) A mesa
Free
Multiple Choice
Q 55Q 55
The angle of repose of sand-sized particles falling from the air is _____ degrees.
A) 14
B) 24
C) 34
D) 44
E) 90
Free
Multiple Choice
Q 56Q 56
An area with desert conditions in the United States is ____.
A) the Sahara
B) the southern Appalachians
C) the Colorado Plateau
D) the Pacific Northwest coast
E) Minnesota
Free
Multiple Choice
Q 57Q 57
The high runoff following sporadic desert downpours can create sudden local floods called ______.
A) ephemeral floods
B) flash floods
C) spring floods
D) storm surges
E) desert disasters
Free
Multiple Choice
Q 58Q 58
Where sand supply is limited a _____ dune usually forms.
A) blowout
B) star
C) longitudinal
D) barchan
E) seif
Free
Multiple Choice
Q 59Q 59
Dunes are not just desert features, they are commonly found near ____.
A) glaciers
B) beaches
C) rivers
D) folds
E) exposed rock
Free
Multiple Choice
Q 60Q 60
Rock debris picked up in flash floods is deposited at the base of mountains in ____.
A) an alluvial fan
B) a barchan dune
C) a playa
D) an arroyo
E) a meandering river
Free
Multiple Choice