Chapter 7 Glaciers, Deserts, and Wind Flashcards
Which of the following is true about ice sheets?
a. They are the smallest type of glacier.
b. They flow in all directions.
c. They usually flow down valleys.
d. They are found only in high mountain areas.
b. They flow in all directions.
Where is almost two thirds of Earth’s fresh water located?
a. the Arctic Ice Sheet
b. the Great Lakes
c. the Antarctic Ice Sheet
d. the Atlantic Ocean
c. the Antarctic Ice Sheet
In a flowing glacier,
a. the lower ice layer is brittle, while the upper layer moves
over Earth’s surface.
b. the entire glacier moves as a unit over Earth’s surface.
c. the uppermost ice layer is more brittle than the
underlying layer.
d. there are no crevasses.
c. the uppermost ice layer is more brittle than the
underlying layer.
One characteristic of glacial movement is that
a. all glaciers, regardless of size, move at about the
same rate.
b. new snowfall accumulates in a zone at the bottom
of the glacier.
c. the zone of wastage is at the top of the glacier.
d. how the glacier moves depends on the balance between
accumulation and wastage.
d. how the glacier moves depends on the balance between
accumulation and wastage.
What is the loosening and lifting of blocks of rock by glaciers? a. plucking b. wastage c. abrasion d. till
a. plucking
What is a bowl-shaped depression at the head of a glacial valley? a. glacial trough b. arête c. horn d. cirque
d. cirque
What is material deposited directly by a glacier?
a. a kettle
b. a drumlin
c. till
d. stratified drift
c. till
Eskers are glacial features formed when
a. blocks of stagnant ice become buried in drift and
eventually melt.
b. sediment is deposited in a broad ramp-like accumulation
downstream from the end moraine.
c. streams flowing in tunnels beneath glaciers deposit sand
and gravel.
d. large amounts of debris are deposited along the sides
of a glacial valley.
c. streams flowing in tunnels beneath glaciers deposit sand
and gravel.
In the desert, ephemeral streams
a. run continuously, although the amount of flow varies.
b. run only after it rains.
c. are actually dried stream beds that no longer carry water.
d. carry water underground.
b. run only after it rains.
What causes the rust-colored tint of some desert landscapes?
a. chemical weathering
b. mechanical weathering
c. flash flooding
d. the intense heat of the sun
a. chemical weathering
Why is rock weathering generally reduced in the desert
environment?
a. Rocks are very scarce in deserts.
b. Most rocks are buried deep within the soil.
c. Moisture is lacking and organic acids are scarce.
d. The soil is so well developed.
c. Moisture is lacking and organic acids are scarce.
Desert pavement is created as a result of
a. abrasion.
b. deflation.
c. blowouts.
d. water erosion.
b. deflation.
Deflation affected the Dust Bowl in the 1930s by
a. creating rock pinnacles.
b. building up sand dunes.
c. depositing loess.
d. lowering the land.
d. lowering the land.
Abrasion changes the desert surface by
a. creating blowouts.
b. cutting and polishing exposed rock surfaces.
c. depositing loess across the landscape.
d. creating a stony surface layer.
b. cutting and polishing exposed rock surfaces.
What causes abrasion in a desert?
a. wind
b. flowing water
c. humidity
d. friction from rocks
a. wind
Windblown silt that blankets a landscape is called
a. a blowout.
b. a sand dune.
c. desert pavement.
d. loess.
d. loess.
When wind creates a sand dune, the sheltered side
of the dune
a. forms a gentle incline.
b. has the same incline as the windward side.
c. is steeper than the windward side.
d. continues to rise higher than the windward side.
c. is steeper than the windward side.
Over time, how do sand dunes tend to migrate?
a. perpendicular to the movement of the wind
b. in the same direction as the wind blows
c. toward the wind
d. in random directions
b. in the same direction as the wind blows
What is a sand dune that forms scalloped rows of sand at right angles to the wind? a. star dunes b. transverse dunes c. parabolic dunes d. barchanoid dunes
d. barchanoid dunes
The shape of star dunes is mostly due to
a. the amount of vegetation.
b. wind direction.
c. wind speed.
d. the amount of sand.
b. wind direction.
The small glaciers that exist in high mountainous areas are called
valley glaciers
The only ____________ that exist today are found covering
Greenland and Antarctica.
ice sheets
The way a glacier moves depends on the balance, or lack of
balance, between __________ and wastage.
accumulation
In the ___________ process, glaciers smooth and polish
the bedrock below, creating a pulverized substance called rock flour.
abrasion
A U-shaped __________ results after a glacier moves
through a narrow V-shaped valley.
glacial trough
____________ is unsorted sediment laid down by glacial
meltwater.
Stratified drift
A broad, ramp-like accumulation of sediment called a(n) ____________
is found downstream from the end moraine of a glacier.
outwash plain
The __________ Lakes are lowlands that glaciers eroded
and transformed into wide, deep basins.
Great
In desert areas, ___________ streams can cause a great
deal of erosion in a very short period of time.
ephemeral
A(n) ____________ is a cone of debris left at the mouth
of a desert canyon.
alluvial fan
Loose particles such as clay and silt are lifted and removed from
the desert surface by a process called ___________.
deflation
Desert rock surfaces are cut and polished by windblown sand
in the ____________ process.
abrasion
The color of the Yellow River in China is produced by abundant
deposits of buff-colored sediments called ____________.
loess
Most sand dunes have a gently sloping ____________ side
and a steeper ____________ side.
windward
sheltered
The “sand seas” found in the Sahara are ____________
dunes because they form perpendicular to the direction of
the wind.
transverse
