Deck 18: Glaciers and Glaciation

Question 1

________ are stratified sands and gravels carried away from the glacial terminus by meltwater.

A)Loess
B)Outwash
C)Till
D)Diamicton

Answer 1

B

Question 2

Which crevasse will form perpendicular to the terminus as a glacier stretches to fill a valley?

A)Esker
B)Longitudinal
C)Transverse
D)Moulin

Answer 2

B

Question 3

What percentage of the Earth's land surface is currently covered by glacial ice?

A)2%
B)10%
C)15%
D)33%

Answer 3

B

Question 4

When was the Last Glacial Maximum?

A)18,000 years ago
B)10,000 years ago
C)100,000 years ago
D)32,000 years ago

Question 5

A(n)________ is a sharp mountain peak created by erosion from several cirque glaciers.

A)arête
B)cirque
C)glacial trough
D)horn

Question 6

Glaciers form because of the accumulation of large amounts of ice and snow.Which of the following provides the most water needed to create glaciers?

A)Groundwater
B)Geysers
C)Oceans
D)Streams

Question 7

________ is an elevation point above which snow remains throughout the year.

A)Firn
B)Snowline
C)Grounding line
D)Surge

Question 8

A(n)________ is a sharp, knife-edged ridge that forms between two valley glaciers.

A)horn
B)arête
C)col
D)moraine

Question 9

Which of the following locations does not currently have glaciers?

A)Norway
B)Antarctica
C)Scotland
D)Alaska

Question 10

Ice shelves are grounded in ________ and float in ________.

A)saltwater; freshwater
B)shallow water; deep water
C)freshwater; shallow water
D)deep water; shallow water

Question 11

The Hubbard Glacier in North America is an example of which kind of glacier?

A)Valley
B)Ice Sheet
C)Piedmont
D)Cirque

Question 12

The Laurentide Ice Sheet is an example of ________ glaciation.

A)alpine
B)valley
C)continental
D)ice cap

Question 13

Which part of a glacier is responsible for abrasion and plucking?

A)Basal sliding zone
B)Glacial interior
C)Terminus
D)Brittle surface zone

Question 14

Which crevasse will form parallel to the terminus as a glacier moves over a change in slope?

A)Bergschrund
B)Longitudinal
C)Transverse
D)Moulin

Question 15

________ is an erosional method where meltwater penetrates fractures in subglacial bedrock and freezes.

A)Plucking
B)Comminuting
C)Spalling
D)Abrasion

Question 16

Arêtes, horns, and hanging valleys are evidence of ________ glaciation.

A)alpine
B)ice shelf
C)continental
D)ice cap

Question 17

Which of the following ice bodies is an example of alpine glaciation?

A)Valley
B)Ice Sheet
C)Ice Cap
D)Iceberg

Question 18

What shape do glacial troughs generally display?

A)V
B)W
C)Y
D)U

Question 19

________ is fine silt generated by glaciers that can be carried for long distances by the wind.

A)Loess
B)Outwash
C)Till
D)Diamicton

Question 20

A ________ is a small, circular lake that occupies a cirque basin.

A)drift
B)marsh
C)tarn
D)fenster

Question 21

What is a pluvial lake?

A)A lake that forms on the margins of glaciers from glacial meltwater
B)A lake that fills in an arid/semiarid region due to increased precipitation in a cooler, wetter climate
C)A lake forming from a stagnant piece of melting glacial ice caught between two recessional moraines
D)A subterranean lake forming in a sinkhole

Question 22

Read the following excerpt from The Works of John Playfair (1822).What glacial landform is being described? "…For the moving of large masses of rock, the most powerful engines without doubt that nature employs are the glaciers….[Rock] fragments they gradually transport to their utmost boundaries, where a formidable wall ascertains the magnitude, and attests the force, of the great engine by which it was erected."

A)Arête
B)Drumlin
C)Horn
D)Moraine

Question 23

________ is unsorted, unstratified, bimodal sediment directly deposited by the glacial ice.

A)Loess
B)Outwash
C)Till
D)Diamicton

Question 24

Which of the following is not part of the Milankovitch Cycle?

A)Precession
B)Obliquity
C)Eccentricity
D)Isostacy

Question 25

Deposits of stratified sands and gravels transported from the glacial margin by meltwater are called a(n)________ when adjacent to an ice sheet and a(n)________ when adjacent to an alpine glacier.

A)lateral moraine; kame
B)drumlin; outwash plain
C)outwash plain; valley train
D)terminus; esker

Question 26

________ are former river valleys that were oriented parallel to the direction of ice flow and were scoured deeper by advancing glacial ice.

A)Hanging valleys
B)Paternosters
C)Finger lakes
D)Kettle lakes

Question 27

How does isostatic rebound affect a glacial landscape after the glacier is removed?

A)A depressed crust rises after glacial retreat.
B)Advancing glaciers erode bedrock, which allows rock to spring up.
C)Meltwater streams deposit sediment, severely depressing the landscape.
D)Weight of water forces the crust downward.

Question 28

Which state would you not expect to contain drumlins, eskers, and kettle lakes?

A)Minnesota
B)New York
C)Kentucky
D)Michigan

Question 29

Which moraine marks the furthest extent of glacial ice?

A)Lateral moraine
B)Medial moraine
C)Recessional moraine
D)Terminal moraine

Question 30

Which glacial erosion feature is likely to contain a waterfall today?

A)Tarn
B)Hanging valley
C)Esker
D)Horn

Question 31

Why would construction businesses find eskers to be economically important?

A)They provide flat areas for transportation routes.
B)They provide nutrient-rich farmland.
C)They provide easy access to water sources.
D)They provide easily accessible sand and gravel deposits.

Question 32

Which of the following scenarios can lead to the formation of a kame?

A)Sediment accumulates in a hole in the ice.
B)Sediment is carried on top of the glacier.
C)Sediment collects in subglacial stream channels.
D)Sediment covers a stagnant block of ice.

Question 33

What bodies of water are formed when a stagnant block of glacial ice near the terminus becomes partly or completely buried in glacial sediments, eventually melting to create a lake?

A)Tarns
B)Paternosters
C)Braided streams
D)Kettle lakes

Question 34

Which of the following descriptions does not specifically apply to sediments carried away from the glacier by meltwater streams?

A)Deposited in stratified layers
B)Composed of clay-rich materials
C)Often well sorted
D)Composed of sands and gravels

Question 35

There have been several instances in the last 150 years when valuable materials such as diamonds have been found contained in glacial debris.If one wanted to try to trace such valuable materials back to their source, which moraine would be most useful for tracing valuable gold deposits back to their bedrock source area?

A)Recessional moraine
B)Terminal moraine
C)Lateral moraine
D)Esker

Question 36

What was the most recent episode of glaciation in North America?

A)Nebraskan Episode
B)Kansan Episode
C)Illinois Episode Glaciation
D)Wisconsin Episode Glaciation

Question 37

Which of the following best explains the formation of a medial moraine on a glacier?

A)A gravel pile that marks periods of glacial readvancement
B)A ridge of debris carried down the center of glacial ice
C)Sands and gravels that fill a subglacial stream channel
D)A ridge of debris carried along the sides of an advancing glacier

Question 38

Which continent had the greatest area covered by glaciers at the height of the Ice Age?

A)South America
B)Asia
C)North America
D)Europe

Question 39

________ is the name for glacial deposits that have been lithified into a sedimentary rock.

A)Tillite
B)Loessite
C)Sandstone
D)Schist

Question 40

Lateral and medial moraines are found in connection with ________ glaciation.

A)alpine
B)ice shelf
C)continental
D)ice cap

Question 41

The amount of solar radiation coming in at ________ helps to determine whether or not a planet is going into an Ice Age.

A)10° S
B)45° N
C)76° S
D)65° N

Question 42

Land on the margins of continents that is presently under water would have been exposed to the atmosphere during glaciations because sea level would have been dozens of meters lower at that time.

Question 43

In order for a bimodal sediment to be called till, it must be directly deposited by glacial ice.If it is not, it is referred to as a diamicton.

Question 44

Sea level rises during a glaciation because glaciers are pushing down on the crust, which deforms the ocean basins.

Question 45

Because sea level does not act like base level with glaciers, a glacier can erode its bed below sea level.

Question 46

When the three parts of the Milankovitch Cycle align, there will be harsher winters in the middle to high latitudes with less snowfall and warmer summers bringing an increase in snowmelt.

Question 47

Glaciers form in areas where more snow falls in the winter than is lost in the summer.

Question 48

Most glaciers worldwide are currently in a state of retreat.

Question 49

Glaciers in arctic regions that are frozen to their beds move via internal deformation.

Question 50

When did the ice-free corridor open in North America, allowing a path for human migration from Asia?

A)12,500 years ago
B)9,000 years ago
C)100,000 years ago
D)7,500 years ago

Question 51

The Earth is still in an Ice Age today because there are still glaciers on the planet.

Question 52

A kame is an ice-contact deposit.

Question 53

Outwash sediments are stratified by wind deposition.

Question 54

________ refers to the change in the angle Earth's axis makes with the plane of our planet's orbit.

A)Subduction
B)Eccentricity
C)Obliquity
D)Precession

Question 55

Glaciers are a single, solid piece of ice that flows from the Zone of Accumulation to the Zone of Saturation.

Question 56

A glacier takes hundreds of thousands of years to form, but only a few thousand years to disappear.

Question 57

The North American continent was covered by more ice than the South American continent at the height of the Ice Age.

Question 58

How would plate tectonics explain the glaciation at the end of the Paleozoic Era, when no evidence of glacial ice can be found in high-latitude areas of North America and Eurasia?

A)The climate was too warm for glacial ice on those continents.
B)The glaciation was very small.
C)The continents were joined to form Pangaea, which was located around the South Pole.
D)There was an increased amount of solar radiation penetrating the atmosphere above those continents.

Question 59

The only continental ice sheets left on Earth today are in Greenland and Antarctica.

Question 60

When a glacier is in retreat, the ice can flow from the Zone of Ablation to the Zone of Accumulation.

Question 61

Which direction was the ice flowing (Hint: It is bedrock.)

A)Bottom to top
B)Left to right
C)Top to bottom
D)Right to left

Question 62

What factor(s)might lead glaciers to basal slip?

Question 63

North American glaciations used to be described in four episodes.However, two of those episode names, the Kansan and Nebraskan, are no longer used.What evidence did scientists use to redefine the glacial history on the North American continent?

Question 64

What evidence of glacial erosion is visible in this image?

A)Crevasses
B)Striations
C)Faults
D)Outwash

Question 65

Glacial Lake Agassiz went through many periods of catastrophic drainage starting at 13,000 years ago.Some of these periods of catastrophic change have been linked to periods of cooling climate, particularly when the lake drained through the St.Lawrence Seaway and into the North Atlantic.How would the drainage of Lake Agassiz affect the climate to such a degree that cooling would result?

Question 66

Evaluate the following statement: "Continental ice sheets generally subdue their landscapes, whereas alpine glaciers accentuate them."

Question 67

Compare and contrast proglacial lakes and pluvial lakes.

Question 68

How does ground moraine form? Relate the formation of ground moraine to changes in climate.

Question 69

During the Wisconsin Episode Glaciation, a glacial forebulge formed just off the coast of British Columbia in the vicinity of Queen Charlotte Island.What is a glacial forebulge and how did this one form?

Question 70

Explain how the presence of glaciers on the planet affects the albedo of the land surface.How will the albedo change as glaciers melt? What will this mean for the climate?

Question 71

The Zone of Fracture in a glacier is found in the uppermost 50 m of glacial ice.Explain why ice fractures above this depth, but not below.

Question 72

How does the formation of a hanging valley differ from the formation of the main glacial trough?

Question 73

The Mississippi River currently makes up the western boundary of the state of Illinois.However, the Ancient Mississippi River Valley once flowed through the center of the state, cutting off one-quarter of the state from its modern boundaries.How did the Mississippi River shift from its ancestral location to its present one? How did it end up staying in its current location? Explain.

Question 74

How is isostatic rebound affecting the Lake Michigan Basin?

Question 75

What factors influence the rate of glacial erosion?

Question 76

What erosional feature is visible in this image? (Hint: It is bedrock.)

A)Arête
B)Moraine
C)Drumlin
D)Roche moutonnée

Question 77

Which method of glacial erosion is responsible for the marks in this image?

A)Abrasion
B)Plucking
C)Quarrying
D)Jointing

Question 78

What substance is responsible for the turquoise color of the water in this image?

A)Till
B)Outwash
C)Oxidation
D)Rock flour

Question 79

How does a glacial fjord form? What does it tell us about climate change after glaciation?

Question 80

How does an ice cap compare to an ice sheet?