Deck 22: Amazing Ice: Glaciers and Ice Ages

Question 1

Cirques and horns are features associated with ________.

A) mountain glaciation
B) continental glaciation
C) glacial outwash deposits
D) loess deposits

Answer 1

A

Question 2

During the last ice age,a ________ glacier covered much of the northern United States.

A) piedmont
B) cirque
C) mountain
D) continental

Answer 2

D

Question 3

What type of glacier is seen in the foreground of the following picture?

A) a continental glacier
B) a cirque glacier
C) a piedmont glacier
D) an alpine glacier

Answer 3

C

Question 4

Ice is a substance with a high albedo,which means it ________.

A) requires much heat to raise its temperature by 1°C
B) absorbs most of the light that falls on it
C) reflects most of the light that falls on it
D) strongly refracts the light that falls on it

Question 5

A glacier will always advance from its source area if the rate of accumulation is greater than the rate of ________.

A) subsidence
B) erosion
C) ablation
D) uplift

Question 6

At the present,glaciers cover about ________ of the surface of the continents.

A) 1%
B) 5%
C) 10%
D) 20%

Question 7

Glacial ice cores can be used to determine the atmospheric concentration of CO₂ during the Earth's history.How do scientists come up with these data?

A) They use the thickness of the ice layers to determine how much CO₂ was in the atmosphere.
B) They melt the ice and measure how much carbon was trapped in the ice.
C) They record changes in the shape of ice crystals to determine the paleoclimate.
D) They break the ice apart,release the air trapped in bubbles,and then measure the gases.

Question 8

The current interglacial interval began a little more than ________ years ago.

A) 1,000
B) 10,000
C) 100,000
D) 1 million

Question 9

Glacial ice exhibits ________ behavior near the top but ________ behavior at a depth of more than 60 m.

A) brittle; plastic
B) plastic; brittle
C) solid; elastic
D) plastic; elastic

Question 10

Glaciers form as fresh ________ falls to the ground and accumulates.The accumulation adds pressure,which compresses the ________ until they form a packed granular material called ________.Some material melts and then ________ in the pore spaces to create a solid mass of ice.

A) snow; snowflakes; cirques; dissolves
B) snow; snowflakes; firn; refreezes
C) ice; ice; firn; refreezes
D) firn; glacier; ice; gets trapped

Question 11

An intermediate product in the transformation of snow to glacial ice is ________.

A) firn
B) deposition
C) ablation
D) terminus

Question 12

Boulders left behind by glacial ice are known as __________.

A) till
B) erratics
C) piedmont
D) horns

Question 13

Today,continental glaciers are limited to Antarctica and ________.

A) Alaska
B) Greenland
C) Canada
D) Siberia

Question 14

The polar ice caps on Mars are an example of what type of glacier?

A) continental glacier
B) cirque glacier
C) piedmont glacier
D) valley glacier

Question 15

Which of the following statements is true of flowing water and glacial ice?

A) Both flowing water and glacial ice are capable of sorting sediments based on clast size.
B) Flowing water will sort sediment based on clast size; glacial ice will not.
C) Glacial ice will sort sediment based on clast size; flowing water will not.
D) Neither flowing water nor glacial ice will sort sediment based on clast size.

Question 16

At depths of greater than 60 m,ice moves by plastic deformation.What causes this transition from brittle to ductile behavior?

A) A decrease in temperature causes the glacier to melt and slide.
B) An increase in pressure increases friction and melts the ice.
C) An increase in the pressure allows for only minute deformation.
D) A decrease in the amount of trapped sediments allows more flow.

Question 17

An angular peak surrounded by three or more bowl-shaped depressions formed by a mountain glacier is termed a(n)________.

A) arête
B) cirque
C) horn
D) tarn

Question 18

Glacial deposits consist primarily of __________.

A) very fine-grained material
B) very coarse-grained material
C) very well-sorted material
D) very poorly sorted material

Question 19

A bowl-shaped depression formed by a mountain glacier is termed a(n)________.

A) arête
B) cirque
C) horn
D) tarn

Question 20

Currently,almost all the glaciers on the Earth are in a state of retreat,which means that the rate of ________ is less than the rate of ________.

A) accumulation; ablation
B) ablation; accumulation
C) formation; sublimation
D) calving; advance

Question 21

You are hiking in your favorite forest when you encounter a surface that appears to have very fine scratches in it.What are these features?

A) glacial till
B) moraines
C) striations
D) scour marks

Question 22

Identify the farthest reach of the glacier in the figure below.

A) E
B) C
C) G
D) F

Question 23

Identify the esker in the figure below.

A) E
B) C
C) A
D) F

Question 24

If you wander around Central Park in New York City,you will eventually encounter random,large boulders that are made of a type of rock not found in the area.How did these large boulders get to Central Park?

A) The Parks and Recreation Department placed them there for kids to play on.
B) They were carried by rivers and deposited in point bars.
C) They were carried by glaciers and dropped as glacial erratics.
D) They were placed there by a giant tsunami millions of years ago.

Question 25

A(n)________ in global sea level is ultimately the result of a ________ event.

A) increase; global cooling
B) increase; local uplift
C) decrease; subsidence
D) decrease; global cooling

Question 26

If glaciers carry a mixture of different clast sizes,why are glacial outwash deposits layered?

A) because clasts fall out of the glacier in size progression
B) because gravity pulls out only the smallest particles
C) because glacial outwash is formed from the bottom of the glacier
D) because the glacier does not deposit the sediments; the river does

Question 27

Which of the following figures is of glacial lake-bed deposits?

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

Question 28

Cirques,horns,and arêtes form due to glacial ________,whereas moraines,erratics,and till form from glacial ________.

A) erosion; deposition
B) deposition; carving
C) retreat; advance
D) erosion; sublimation

Question 29

When the sea level rises,causing the ocean to fill a glacially carved valley,a ________ results.

A) cirque
B) tarn
C) fjord
D) estuary

Question 30

Sediments deposited directly by glaciers as they melt are characterized by ________.

A) uniformly coarse grain size
B) uniformly fine grain size
C) an absence of sorting
D) graded bedding

Question 31

Stratified sorted sand and gravel are deposited by ________.

A) mountain glaciers
B) continental glaciers
C) glacial outwash streams
D) windstorms

Question 32

A hanging valley is formed when a ________.

A) smaller glacially carved valley intersects with a larger glacially carved valley
B) smaller stream-cut valley intersects with a larger stream-cut valley
C) smaller stream-cut valley intersects with a larger glacially carved valley
D) stream-cut valley is on the upthrust side of a normal fault

Question 33

Sediments deposited directly by glaciers as they melt are ________.

A) firn
B) loess
C) outwash
D) till

Question 34

Identify the area where layered sediments have been deposited in the figure below.

A) E
B) C
C) A
D) F

Question 35

Using the figure below,identify which way the glacier advanced.

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

Question 36

Valleys carved by glaciers tend to be shaped like the letter ________,whereas valleys carved by water tend to be shaped like the letter ________.

A) V; U
B) V; C
C) U; V
D) I; V

Question 37

Moraines are composed of jumbled piles of very poorly sorted rock fragments ranging in size from boulder to clay that fall out near the edges of glaciers.Why are the larger particles (boulders,etc.)not broken down during transport in the glacier?

A) because the ice is not strong enough to break up rock
B) because sediments are picked up and carried along with the ice as it moves
C) because the sediments are not carried for very long distances
D) because the ice stops the chemical weathering processes

Question 38

What types of moraines are shown prominently in the figure below?

A) medial moraines
B) terminal moraines
C) lateral moraines
D) recessional moraines

Question 39

Wind blows finer particles long distances from glacial environments,where they settle out to form ________.

A) firn
B) loess
C) outwash
D) till

Question 40

Which types of features would you find in a glacially eroded landscape?

A) eskers,drumlins,cirques,and kettles
B) cirques,arêtes,horns,and moraines
C) cirques,arêtes,kettles,and tarns
D) drumlins,ground moraines,and arêtes

Question 41

List and describe one short-term cause for glaciations.

Question 42

Label the glaciers in the image below using words from the word bank included.(Hint: not all the names will be used.)

Question 43

Examine the graph below.There have been ________ to ________ ice ages in the Earth's history,with the latest one occurring in the ________.

A) four; five; Pleistocene Period
B) five; six; Pleistocene Period
C) four; five; Proterozoic Era
D) five; six; Cenozoic Era

Question 44

Notice the boulders in the center of this picture of a glacially formed landscape.What are they? How did they get there?

Question 45

What happens to global sea level during times of increased glaciation? During interglacial periods? Why?

Question 46

What are the circumstances that lead to glacial advance versus glacial retreat? Most glaciers today are in retreat.What does this imply about the glaciers and their environment?

Question 47

Describe what you would expect to see in glacial till deposit.Why?

Question 48

Contrast a glacially carved valley with one carved by a river.

Question 49

The loss of rainforests would ________ the greenhouse gases,thereby ________ global warming.

A) increase; increasing
B) increase; decreasing
C) decrease; increasing
D) decrease; decreasing

Question 50

You and some friends are going on a road trip and one of your goals is to see a glacier.Where could you go in the continental United States to do this? What type of glacier will you most likely be visiting?

Question 51

In the movie Ice Age: The Meltdown,there is a large wall of ice that begins to melt and finally breaks,causing a large flood.What real-life geologic event was this part of the movie based on?

A) the destruction of Glacial Lake Missoula
B) the formation of the Great Salt Lake
C) the breakup of the Ross Ice Shelf
D) the draining of Lake Bonneville

Question 52

Explain why the deposits made by glacial outwash are stratified.

Question 53

Imagine that you live in a desert.Installing a roof that is a light tan color would help ________ your house by ________ the albedo.

A) warm; increasing
B) warm; decreasing
C) cool; increasing
D) cool; decreasing

Question 54

The effect of periodic changes in the Earth's orbital eccentricity and magnitude and direction (precession)of its axial tilt on the advance and retreat of ice sheets was first proposed by ________.

A) Richter
B) Milankovitch
C) Mohorivic
D) Lyell

Question 55

By increasing the albedo of the Earth,global ice sheets produce conditions that are ________ to their further advance,thus providing an example of ________ feedback.

A) detrimental; positive
B) detrimental; negative
C) favorable; positive
D) favorable; negative

Question 56

Imagine you are living in your current home but during the Pleistocene Ice Age.Contrast the present climate with that of your new climate in the Pleistocene.In one sentence,summarize how the climate is different now.

Question 57

During the Pleistocene Ice Age,all the climate belts of the northern hemisphere shifted to the __________.

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

Question 58

An important long-term factor that determines whether glacial ice will form on a continent has likely been the proportion of which gas in the atmosphere?

A) oxygen
B) nitrogen
C) carbon dioxide
D) carbon monoxide

Question 59

The formation of continental glaciers ____________ the weight of the lithosphere causing it to __________.

A) increases; subside
B) increases; uplift
C) decreases; subside
D) decreases; uplift

Question 60

The Milankovitch cycles describe the change in ________ because of changes in the ________ of the Earth relative to the Sun.

A) greenhouse gases; tilt
B) eccentricity; orientation
C) albedo; precession
D) solar insolation; orientation