Deck 18: Amazing Ice: Glaciers and Ice Ages

Question 1

A remnant ridge separating two bowl-shaped depressions formed by a mountain glacier is termed a(n)____________.

A) arête
B) cirque
C) horn
D) tarn

Answer 1

A

Question 2

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

Answer 2

C

Question 3

The first scientist to theorize the past presence of glaciers in Europe was ____________.

A) Isaac Newton
B) Charles Darwin
C) Walter Alvarez
D) Louis Agassiz

Answer 3

D

Question 4

A lake that forms within a bowl-shaped depression formed by a mountain glacier is termed a(n)____________.

A) arête
B) cirque
C) horn
D) tarn

Question 5

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

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

Question 6

Mars has polar ice caps that differ from the Earth's Antarctic ice cap in that ____________.

A) the Martian caps consist of a combination of water ice and frozen carbon dioxide (dry ice)
B) the Martian caps have a spiral fracture pattern not found in Antarctica
C) Martian caps are ablated by sublimation only; there is currently no liquid water on Mars
D) All of the above are correct.

Question 7

Glacial ice exhibits ____________ behavior near the top,but ____________ behavior beneath a depth of 60 m.

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

Question 8

Stratified,sorted sand and gravel are deposited by ____________.

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

Question 9

Because glacial advance is driven by gravity,it is impossible for glaciers to advance over perfectly flat terrain.

Question 10

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

A) subsidence
B) melting
C) ablation
D) abrution

Question 11

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

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

Question 12

Cape Cod,Massachusetts,and Long Island,New York,are both examples of Pleistocene glacial ____________ that have been further built up by wave-deposited sands.

A) drumlins
B) kettles
C) eskers
D) end moraines

Question 13

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

A) 1000
B) 10,000
C) 100,000
D) 1,000,000

Question 14

Walking across an Antarctic ice sheet during winter would not be very treacherous,because icy surfaces are not slippery if the temperature is well below freezing.

Question 15

A hanging valley is formed when a ____________.

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

Question 16

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

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

Question 17

Cirques and horns are features associated with ____________.

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

Question 18

Today,continental glaciers are limited to Antarctica and ____________.

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

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

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 21

That periodic changes in Earth's orbital eccentricity and magnitude,as well as in the direction (precession)of Earth's axial tilt,affect the advance and retreat of ice sheets was first proposed by ____________.

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

Question 22

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 23

Areas on the southern margins of the continental glaciers of the northern hemisphere were much ____________ during Plio-Pleistocene glaciations than they are today,as suggested by evidence of large ____________ during this time.

A) warmer; tropical rainforests
B) wetter; tropical rainforests
C) drier; deserts
D) wetter; pluvial lakes

Question 24

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

A) smorgasbord
B) tarn
C) fjord
D) ford

Question 25

Given the modern continental configuration,it is much easier for large continental ice sheets to become established in the ____________ hemisphere than in the ____________ hemisphere.

A) eastern; western
B) western; eastern
C) northern; southern
D) southern; northern

Question 26

An important long-term factor determining whether glacial ice will form on the continents has likely been the proportion of which gas in the atmosphere?

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

Question 27

Sediments deposited directly by glaciers as they melt are termed ____________.

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

Question 28

Advance and retreat of massive glacial ice sheets during glacial episodes is a simple function of incident sunlight.Glacial behavior can be modeled precisely by considering only Milankovitch orbital variation and variable solar output.

Question 29

Two mountain glaciers merge their flows in a glacial valley.Prior to their merger,each possessed two lateral moraines and no medial moraines.As a result of a merger,the new larger glacier in the valley will possess ____________.

A) four lateral moraines and no medial moraines
B) three lateral moraines and no medial moraines
C) two lateral moraines and two medial moraines
D) two lateral moraines and one medial moraine

Question 30

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

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