Question 1

Which of the following best describes the deposit left by a flash flood?

Accepted Answer

A) a combination of desert pavement and loess 
B) a flat deposit of coarse debris 
C) channel,levee,and floodplain deposits 
D) thin deposits of evaporites 
A) a combination of desert pavement and loess 
B) a flat deposit of coarse debris 
C) channel,levee,and floodplain deposits 
D) thin deposits of evaporites B

Question 2

Why does much of a desert's surface consist of sand,gravel,and rock rubble?

Accepted Answer

A) because clay minerals form slowly in a desert environment 
B) because wind blows away clay and soil before it can accumulate to great thickness 
C) because vegetation is sparse and cannot prevent erosion of soil 
D) all of the above 
A) because clay minerals form slowly in a desert environment 
B) because wind blows away clay and soil before it can accumulate to great thickness 
C) because vegetation is sparse and cannot prevent erosion of soil 
D) all of the above D

Question 3

Which of the following statements is true?

Accepted Answer

A) Air flows and stream flows are mostly laminar. 
B) Air flows are mostly laminar; stream flows are mostly turbulent. 
C) Air flows are mostly turbulent; stream flows are mostly laminar. 
D) Air flows and stream flows are mostly turbulent. 
A) Air flows and stream flows are mostly laminar. 
B) Air flows are mostly laminar; stream flows are mostly turbulent. 
C) Air flows are mostly turbulent; stream flows are mostly laminar. 
D) Air flows and stream flows are mostly turbulent. D

Question 4

What ultimately limits the height of a sand dune?

Accepted Answer

A) the amount of sand it contains 
B) saltation 
C) wind speed 
D) air temperature 
A) the amount of sand it contains 
B) saltation 
C) wind speed 
D) air temperature

Question 5

What is the Coriolis effect?

Accepted Answer

A) a type of air circulation 
B) the effect of Earth's rotation on global air circulation 
C) local weather effects 
D) the effect of solar flares on Earth's climate 
A) a type of air circulation 
B) the effect of Earth's rotation on global air circulation 
C) local weather effects 
D) the effect of solar flares on Earth's climate

Question 6

Over the past 20 million years,the interior of Australia has changed from a moist,humid climate to a desert.Why?

Accepted Answer

A) because plate collisions have built mountains near the coastline that block moisture-bearing winds from the continent's interior 
B) because Australia has moved northward into an arid,subtropical zone 
C) because Australia has moved southward out of the path of the more humid trade winds 
D) because the continent has grown through volcanic activity,making the interior too far away from moisture-bearing winds 
A) because plate collisions have built mountains near the coastline that block moisture-bearing winds from the continent's interior 
B) because Australia has moved northward into an arid,subtropical zone 
C) because Australia has moved southward out of the path of the more humid trade winds 
D) because the continent has grown through volcanic activity,making the interior too far away from moisture-bearing winds

Question 7

Most windblown sand consists of

Accepted Answer

A) calcite. 
B) feldspar. 
C) gypsum. 
D) quartz. 
A) calcite. 
B) feldspar. 
C) gypsum. 
D) quartz.

Question 8

Long wavy sand ridges that lie perpendicular to the prevailing wind are called

Accepted Answer

A) barchan dunes. 
B) blowout dunes. 
C) linear dunes. 
D) transverse dunes. 
A) barchan dunes. 
B) blowout dunes. 
C) linear dunes. 
D) transverse dunes.

Question 9

If the North American plate suddenly changed direction and headed due south,then which region of North America would be most prone to desertification?

Accepted Answer

A) Northern California 
B) the northern Great Plains 
C) the Great Lakes region 
D) the Eastern Seaboard 
A) Northern California 
B) the northern Great Plains 
C) the Great Lakes region 
D) the Eastern Seaboard

Question 10

Martian dust storms are a major problem for many of the rovers that have roamed the planet surface.Which one of following rovers would you expect to be least affected by the Martian dust?

Accepted Answer

A) Opportunity 
B) Curiosity 
C) Spirit 
D) Sojourner 
A) Opportunity 
B) Curiosity 
C) Spirit 
D) Sojourner

Question 11

The cross beds exposed in an eolian sandstone dip to the west.During the deposition of the sand,the prevailing winds were probably from the

Accepted Answer

A) east. 
B) north. 
C) south. 
D) west. 
A) east. 
B) north. 
C) south. 
D) west.

Question 12

As a dune grows in height,

Accepted Answer

A) it gets steeper on the leeward side. 
B) saltation becomes less important in sand movement. 
C) wind speeds increase at the top. 
D) it slows down its forward movement. 
A) it gets steeper on the leeward side. 
B) saltation becomes less important in sand movement. 
C) wind speeds increase at the top. 
D) it slows down its forward movement.

Question 13

Which of the following processes describes the gradual erosion of the ground surface by wind?

Accepted Answer

A) deflation 
B) desertification 
C) solifluction 
D) subsidence 
A) deflation 
B) desertification 
C) solifluction 
D) subsidence

Question 14

Temporary lakes that accumulate in arid desert basins are called ______ lakes.

Accepted Answer

A) eolian 
B) erg 
C) playa 
D) wadi 
A) eolian 
B) erg 
C) playa 
D) wadi

Question 15

Which of the following retards deflation?

Accepted Answer

A) construction 
B) motor vehicles 
C) plowing 
D) vegetation 
A) construction 
B) motor vehicles 
C) plowing 
D) vegetation

Question 16

Most of the world's deserts occur in the

Accepted Answer

A) regions around the north and south pole. 
B) regions where the westerlies blow. 
C) regions north and south of the equator knows as the tropics. 
D) regions of elevation above 10,000 meters. 
A) regions around the north and south pole. 
B) regions where the westerlies blow. 
C) regions north and south of the equator knows as the tropics. 
D) regions of elevation above 10,000 meters.

Question 17

Which of the following is a broad,gently sloping platform of bedrock that is left behind as a mountain front eroded in the desert?

Accepted Answer

A) alluvial fan 
B) erg 
C) mesa 
D) pediment 
A) alluvial fan 
B) erg 
C) mesa 
D) pediment

Question 18

Which of the following is an important source of dust?

Accepted Answer

A) volcanic dust from eruptions 
B) clay minerals from soils 
C) organic sources,such as charcoal,pollen,and bacteria 
D) all of the above 
A) volcanic dust from eruptions 
B) clay minerals from soils 
C) organic sources,such as charcoal,pollen,and bacteria 
D) all of the above

Question 19

What is the primary cause of frosting present in the surface of quartz sand grains in the desert?

Accepted Answer

A) abrasion by air currents 
B) dissolution by dew 
C) chemical reaction with feldspar grains 
D) reactions with other sand grains 
A) abrasion by air currents 
B) dissolution by dew 
C) chemical reaction with feldspar grains 
D) reactions with other sand grains

Question 20

Outside of the regular large desert environments (e.g.,the Sahara and the Gobi),sand dunes are found next to lakes and beaches.Why is that?

Accepted Answer

A) Wet or damp sand grains stick together more easily than dry ones. 
B) Water waves,tides,or storms pile the sand up,which starts dunes. 
C) There is ample supply of sand and strong onshore winds. 
D) Near-shore vegetation help trap the sand,allowing large sand dunes to pile up. 
A) Wet or damp sand grains stick together more easily than dry ones. 
B) Water waves,tides,or storms pile the sand up,which starts dunes. 
C) There is ample supply of sand and strong onshore winds. 
D) Near-shore vegetation help trap the sand,allowing large sand dunes to pile up.

Exam 19: Winds and Deserts

Which of the following best describes the deposit left by a flash flood?

Why does much of a desert's surface consist of sand,gravel,and rock rubble?

Which of the following statements is true?

What ultimately limits the height of a sand dune?

What is the Coriolis effect?

Over the past 20 million years,the interior of Australia has changed from a moist,humid climate to a desert.Why?

Most windblown sand consists of

Long wavy sand ridges that lie perpendicular to the prevailing wind are called

If the North American plate suddenly changed direction and headed due south,then which region of North America would be most prone to desertification?

Martian dust storms are a major problem for many of the rovers that have roamed the planet surface.Which one of following rovers would you expect to be least affected by the Martian dust?

The cross beds exposed in an eolian sandstone dip to the west.During the deposition of the sand,the prevailing winds were probably from the

As a dune grows in height,

Which of the following processes describes the gradual erosion of the ground surface by wind?

Temporary lakes that accumulate in arid desert basins are called ______ lakes.

Which of the following retards deflation?

Most of the world's deserts occur in the

Which of the following is a broad,gently sloping platform of bedrock that is left behind as a mountain front eroded in the desert?

Which of the following is an important source of dust?

What is the primary cause of frosting present in the surface of quartz sand grains in the desert?

Outside of the regular large desert environments (e.g.,the Sahara and the Gobi),sand dunes are found next to lakes and beaches.Why is that?

The Earth System

Plate Tectonics: The Unifying Theory

Earth Materials: Minerals and Rocks

Igneous Rocks: Solids From Melts

Sedimentation: Rocks Formed by Surface Processes

Metamorphism: Alteration of Rocks by Temperature and Pressure

Deformation: Modification of Rocks by Folding and Fracturing

Clocks in Rocks: Timing the Geologic Period

Early History of the Terrestrial Planets

History of the Continents

Geobiology: Life Interacts With Earth

Volcanoes

Earthquakes

Exploring Earths Interior

The Climate System

Weathering,erosion,and Mass Wasting: Interactions Between the Climate and Plate Tectonic Systems

The Hydrologic Cycle and Groundwater

Stream Transport: From Mountains to Oceans

Coastlines and Ocean Basins

Glaciers: the Work of Ice

Landscapes: Tectonic and Climate Interaction

The Human Impact of Earths Environment

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