Question 1

Desert varnish is caused by ____________.

Accepted Answer

A)  pesticide and other pollutant residues 
B)  dusts of iron and magnesium oxides 
C)  dust deposits altered by microorganisms 
D)  carbonate cements with iron impurities, for example, siderite 
A)  pesticide and other pollutant residues 
B)  dusts of iron and magnesium oxides 
C)  dust deposits altered by microorganisms 
D)  carbonate cements with iron impurities, for example, siderite

Question 2

Why is the land surface higher underneath the clumps of vegetation?

Accepted Answer

A)  evaporation, causing compaction of soils 
B)  compaction of the ground from the hoofs of cattle or other grazing animals 
C)  deflation of the ground surface by wind erosion 
D)  excretion of soil particles by the bushes during their lifetimes 
A)  evaporation, causing compaction of soils 
B)  compaction of the ground from the hoofs of cattle or other grazing animals 
C)  deflation of the ground surface by wind erosion 
D)  excretion of soil particles by the bushes during their lifetimes

Question 3

Which of the following is NOT a condition in which cold deserts occur?

Accepted Answer

A)  at low latitudes 
B)  at high elevations 
C)  at latitudes > 60° 
D)  near oceans 
A)  at low latitudes 
B)  at high elevations 
C)  at latitudes > 60° 
D)  near oceans

Question 4

Which of these factors does NOT contribute to the salinity of the Great Salt Lake and similar water bodies?

Accepted Answer

A)  evaporation 
B)  the inflow of water from streams 
C)  the outflow of water from the Great Salt Lake 
D)  chemical weathering 
A)  evaporation 
B)  the inflow of water from streams 
C)  the outflow of water from the Great Salt Lake 
D)  chemical weathering

Question 5

What is the most important difference between a talus deposit and an alluvial fan?

Accepted Answer

A)  size of the clasts 
B)  climate of formation. Alluvial fans form in desert regions; talus forms in all climates. 
C)  the agent that moves clasts: water, for alluvial fans; gravity, for talus 
D)  degree of weathering of clasts. In alluvium, materials have undergone extensive chemical weathering; in talus, clasts have undergone little chemical weathering. 
A)  size of the clasts 
B)  climate of formation. Alluvial fans form in desert regions; talus forms in all climates. 
C)  the agent that moves clasts: water, for alluvial fans; gravity, for talus 
D)  degree of weathering of clasts. In alluvium, materials have undergone extensive chemical weathering; in talus, clasts have undergone little chemical weathering.

Question 6

As compared to humid climates,rates of chemical weathering in deserts are ____________.

Accepted Answer

A)  much faster 
B)  much slower 
C)  very similar 
D)  only a bit slower 
A)  much faster 
B)  much slower 
C)  very similar 
D)  only a bit slower

Question 7

A geologist discovers several lithified horizons that contain ventifacts within matrices material that can be age-dated by carbon-14.Which of the following should the geologist NOT infer,even with good field and laboratory methods of research?

Accepted Answer

A)  average rates of sediment deposition 
B)  the predominant type(s) of geologic materials being transported through the area at the time/age of each soil horizon 
C)  the predominant wind directions and age of each horizon 
D)  the age of the rock from which the ventifacts formed 
A)  average rates of sediment deposition 
B)  the predominant type(s) of geologic materials being transported through the area at the time/age of each soil horizon 
C)  the predominant wind directions and age of each horizon 
D)  the age of the rock from which the ventifacts formed

Question 8

The two deserts with the highest recorded temperatures on Earth are _________.

Accepted Answer

A)  Death Valley, United States, and the Gobi Desert, Mongolia 
B)  the Atacama Desert, Chile, and the Sahara Desert, Libya 
C)  Death Valley, United States, and the Sahara Desert, Libya 
D)  Death Valley, United States, and the Atacama Desert, Chile 
A)  Death Valley, United States, and the Gobi Desert, Mongolia 
B)  the Atacama Desert, Chile, and the Sahara Desert, Libya 
C)  Death Valley, United States, and the Sahara Desert, Libya 
D)  Death Valley, United States, and the Atacama Desert, Chile

Question 9

The factors that control the shapes of sand dunes include all of the following EXCEPT for _________.

Accepted Answer

A)  the average speed of wind when it blows 
B)  the constancy/variability in the direction that moderate and strong winds blow 
C)  the supply of sand 
D)  the size fraction of sand that composes the dunes 
A)  the average speed of wind when it blows 
B)  the constancy/variability in the direction that moderate and strong winds blow 
C)  the supply of sand 
D)  the size fraction of sand that composes the dunes

Question 10

What statement describing shared features of alluvial fans and pediment is FALSE?

Accepted Answer

A)  Both form from clastic sediment. 
B)  Both form along flanks of mountains. 
C)  Both form where canyons exit from the side of a mountain range. 
D)  Both have radial or "fan shapes." 
A)  Both form from clastic sediment. 
B)  Both form along flanks of mountains. 
C)  Both form where canyons exit from the side of a mountain range. 
D)  Both have radial or "fan shapes."

Question 11

What meteorological phenomenon controls the formation of subtropical deserts?

Accepted Answer

A)  downwelling of air from the upper atmosphere 
B)  the Coriolis Effect 
C)  upwelling of air 
D)  the cooling and drying effects of cold-water ocean currents that originate at high latitudes 
A)  downwelling of air from the upper atmosphere 
B)  the Coriolis Effect 
C)  upwelling of air 
D)  the cooling and drying effects of cold-water ocean currents that originate at high latitudes

Question 12

In deserts,what is the primary process that causes mesas and buttes to shrink with time?

Accepted Answer

A)  erosion by running water 
B)  erosion by wind 
C)  chemical weathering and downslope creep 
D)  bedrock separation along joints, along cliff-like slopes 
A)  erosion by running water 
B)  erosion by wind 
C)  chemical weathering and downslope creep 
D)  bedrock separation along joints, along cliff-like slopes

Question 13

Which two terms go together?

Accepted Answer

A)  lag deposit and playa 
B)  playa and talus 
C)  talus and evaporate 
D)  deflation and talus 
E)  lag deposit and deflation 
A)  lag deposit and playa 
B)  playa and talus 
C)  talus and evaporate 
D)  deflation and talus 
E)  lag deposit and deflation

Question 14

The Atacama of Chile is a desert primarily because it is located ____________.

Accepted Answer

A)  in the subtropics 
B)  near the South Pole 
C)  near the center of a large continent 
D)  next to a cold ocean current 
A)  in the subtropics 
B)  near the South Pole 
C)  near the center of a large continent 
D)  next to a cold ocean current

Question 15

The most expansive hot deserts on Earth occur in the ____________.

Accepted Answer

A)  tropics, at or near the equator 
B)  subtropics, between 20° and 30° north or south of the equator 
C)  temperate zone, between 30° and 50° north or south of the equator 
D)  in the rainshadows of mountain ranges between 10° and 25° north or south of the equator. 
A)  tropics, at or near the equator 
B)  subtropics, between 20° and 30° north or south of the equator 
C)  temperate zone, between 30° and 50° north or south of the equator 
D)  in the rainshadows of mountain ranges between 10° and 25° north or south of the equator.

Question 16

Which of the following was NOT a factor contributing to the Dust Bowl event in 1933 in the United States and Canada?

Accepted Answer

A)  lower-than-normal rainfall 
B)  high winds 
C)  withering and crumbling of vegetation due to lack of water 
D)  higher-than-normal temperatures 
A)  lower-than-normal rainfall 
B)  high winds 
C)  withering and crumbling of vegetation due to lack of water 
D)  higher-than-normal temperatures

Question 17

Which would be a better place to build a house-at point A or at point B?

Accepted Answer

A)  at A 
B)  at B 
C)  A and B are equally good locations. 
D)  The picture does not provide any useful information for answering the question.. 
A)  at A 
B)  at B 
C)  A and B are equally good locations. 
D)  The picture does not provide any useful information for answering the question..

Question 18

Why would the Antarctic ventifact shown below be black?

Accepted Answer

A)  It is made of dolomite. 
B)  It has been carbonized. 
C)  It is coated with desert varnish. 
D)  It formed from coal. 
A)  It is made of dolomite. 
B)  It has been carbonized. 
C)  It is coated with desert varnish. 
D)  It formed from coal.

Question 19

Which of these factors allows the bouncing of sand grains to exceed 0.5 m in height (off the ground)during saltation?

Accepted Answer

A)  Particle size. Very fine and fine-grained sand may bounce as high as 2 m, after hitting other sand particles in saltation. 
B)  Lower density. Weathered platy minerals (clays and micas, primarily) are lofted further off the ground. 
C)  Bouncing off of bedrock instead of off of other sand or silt grains. 
D)  Air pressure. Extremely low air pressure (as occurs near or within tropical storms and depressions) can allow sand clasts to bounce as much as 2 m in height before being pulled back downward. 
A)  Particle size. Very fine and fine-grained sand may bounce as high as 2 m, after hitting other sand particles in saltation. 
B)  Lower density. Weathered platy minerals (clays and micas, primarily) are lofted further off the ground. 
C)  Bouncing off of bedrock instead of off of other sand or silt grains. 
D)  Air pressure. Extremely low air pressure (as occurs near or within tropical storms and depressions) can allow sand clasts to bounce as much as 2 m in height before being pulled back downward.

Question 20

Some of the physiographic features that cause extreme aridity may be found together within a single desert,but the deserts found in the western United States are primarily due to being located ____________.

Accepted Answer

A)  in the subtropics 
B)  within the rain shadow of one or more mountain ranges 
C)  near the center of a large continent 
D)  next to a cold ocean current 
A)  in the subtropics 
B)  within the rain shadow of one or more mountain ranges 
C)  near the center of a large continent 
D)  next to a cold ocean current

Exam 17: Dry Regions: the Geology of Deserts

Desert varnish is caused by ____________.

Why is the land surface higher underneath the clumps of vegetation?

Which of the following is NOT a condition in which cold deserts occur?

Which of these factors does NOT contribute to the salinity of the Great Salt Lake and similar water bodies?

What is the most important difference between a talus deposit and an alluvial fan?

As compared to humid climates,rates of chemical weathering in deserts are ____________.

A geologist discovers several lithified horizons that contain ventifacts within matrices material that can be age-dated by carbon-14.Which of the following should the geologist NOT infer,even with good field and laboratory methods of research?

The two deserts with the highest recorded temperatures on Earth are _________.

The factors that control the shapes of sand dunes include all of the following EXCEPT for _________.

What statement describing shared features of alluvial fans and pediment is FALSE?

What meteorological phenomenon controls the formation of subtropical deserts?

In deserts,what is the primary process that causes mesas and buttes to shrink with time?

Which two terms go together?

The Atacama of Chile is a desert primarily because it is located ____________.

The most expansive hot deserts on Earth occur in the ____________.

Which of the following was NOT a factor contributing to the Dust Bowl event in 1933 in the United States and Canada?

Which would be a better place to build a house-at point A or at point B?

Why would the Antarctic ventifact shown below be black?

Which of these factors allows the bouncing of sand grains to exceed 0.5 m in height (off the ground)during saltation?

Some of the physiographic features that cause extreme aridity may be found together within a single desert,but the deserts found in the western United States are primarily due to being located ____________.

The Earth in Context

The Way the Earth Works: Plate Tectonics

Patterns in Nature: Minerals

Up From the Inferno: Magma and Igneous Rocks

The Wrath of Vulcan: Volcanic Eruptions

Pages of Earths Past: Sedimentary Rocks

Metamorphism: a Process of Change

A Violent Pulse: Earthquakes

Crags, cracks, and Crumples: Crustal Deformation and Mountain Building

Deep Time: How Old Is Old

A Biography of Earth

Riches in Rock: Energy and Mineral Resources

Unsafe Ground: Landslides and Other Mass Movements

Streams and Floods: the Geology of Running Water

Restless Realm: Oceans and Coasts

A Hidden Reserve: Groundwater

Amazing Ice: Glaciers and Ice Ages

Global Change in the Earth System

Rock Groups

A Surface Veneer: Sediments and Soils

The Rock Cycle

The Earths Interior Revisited: Insights From Geophysics

Memories of Past Life: Fossils and Evolution

An Introduction to Landscapes and the Hydrologic Cycle

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