Question 1

How and where do glaciers form?

Accepted Answer

Glaciers form in any area where more snow falls than melts during the warmer seasons,so there is a net accumulation.This fresh snow contains about 80% air-filled pore space,but it compacts as new snow falls on it,partially thaws,and refreezes,and eventually makes a granular type of snow called firn.The firn is buried and further compacted as more snow falls,and eventually,it is recrystallized into glacial ice,which contains much less air than fresh snow.

Question 2

What conditions are needed for glaciers to form and be maintained? As a result of these conditions,where are glaciers found?

Accepted Answer

Glaciers form where there is a lot of snowfall and temperatures are cold.Since temperatures are colder at higher altitudes and latitudes,these regions have glaciers if they receive enough snow.The mountains of California receive a lot of snow,but only very high mountains are cold enough to maintain glaciers.Glaciers cover the continents in the far north and south,e.g. ,Greenland and Antarctica.

Question 3

In a cross-section of a glacier,the greatest flow velocities occur:

Accepted Answer

A)  at the surface.
B)  in the few tens of meters below the surface.
C)  in the few tens of meters above the base.
D)  at the base.
E)  in the center of the flow. B

Question 4

The presence of ____________________ in the upper 40 m or so of a glacier indicates that this portion behaves not as a plastic but as a(n)____________________ solid.

Accepted Answer

The answer of The presence of ____________________ in the upper...

Question 5

A glacial landform with steep-walled,pyramidal peaks formed by headward erosion of glaciers on at least three sides is a(n):

Accepted Answer

A)  horn.
B)  esker.
C)  kame.
D)  terminal moraine.
E)  cirque.

Question 6

Finely laminated,alternating light and dark layers of sediment deposited in a glacial lake are known as glacial ____________________.

Accepted Answer

The answer of Finely laminated,alternating light and dark layers of...

Question 7

Near the margins of the Greenland ice sheet,where glacial ice is forced between mountains so that it has an extremely high flow rate,it is called a surging glacier.

Accepted Answer

A) True 
 B)False

Question 8

If the firn limit on a glacier does not change from year to year,the glacier has a balanced snow budget.

Accepted Answer

A) True 
 B)False

Question 9

Continental glaciers are presently found on:

Accepted Answer

A)  Greenland.
B)  Antarctica.
C)  Alaska.
D)  Greenland and Antarctica.
E)  Greenland,Antarctica and Alaska.

Question 10

The Pleistocene Ice Age ended:

Accepted Answer

A)  2.6 million years ago.
B)  10,000 years ago.
C)  1300 years ago.
D)  200 years ago.
E)  It still hasn't ended.

Question 11

There is good evidence that variation in solar energy,as evinced by sunspot activity cycles,is responsible for short-term climatic variations.

Accepted Answer

A) True 
 B)False

Question 12

The zone of ____________________ is the portion of a glacier where additions exceed losses.

Accepted Answer

The answer of The zone of ____________________ is the portion...

Question 13

What are glaciers? How are they as agents of erosion and deposition?

Accepted Answer

The answer of What are glaciers? How are they as...

Question 14

Glaciers are geologically important because they erode,transport,and deposit so much material.

Accepted Answer

A) True 
 B)False

Question 15

The present glacial landscapes mainly formed during an Ice Age that lasted from ____________________ years to ____________________ years ago.

Accepted Answer

The answer of The present glacial landscapes mainly formed during...

Question 16

How does the water bound in glaciers eventually reenter the hydrologic cycle?

Accepted Answer

The answer of How does the water bound in glaciers...

Question 17

A glacier that is now longer flowing is called a(n)____________________ glacier.

Accepted Answer

The answer of A glacier that is now longer flowing...

Question 18

What evidence of their passage do glaciers leave on bedrock?

Accepted Answer

The answer of What evidence of their passage do glaciers...

Question 19

The terms continental glacier and ice sheet are synonymous.

Accepted Answer

A) True 
 B)False

Question 20

Straight scratches on rock surfaces created by glacial abrasion are known as:

Accepted Answer

A)  rock flour.
B)  glacial striations.
C)  glacial till.
D)  varves.
E)  moraines.

Exam 13: Glaciers and Glaciation

How and where do glaciers form?

What conditions are needed for glaciers to form and be maintained? As a result of these conditions,where are glaciers found?

In a cross-section of a glacier,the greatest flow velocities occur:

The presence of in the upper 40 m or so of a glacier indicates that this portion behaves not as a plastic but as a(n) solid.

A glacial landform with steep-walled,pyramidal peaks formed by headward erosion of glaciers on at least three sides is a(n) :

Finely laminated,alternating light and dark layers of sediment deposited in a glacial lake are known as glacial ____________________.

Near the margins of the Greenland ice sheet,where glacial ice is forced between mountains so that it has an extremely high flow rate,it is called a surging glacier.

If the firn limit on a glacier does not change from year to year,the glacier has a balanced snow budget.

Continental glaciers are presently found on:

The Pleistocene Ice Age ended:

There is good evidence that variation in solar energy,as evinced by sunspot activity cycles,is responsible for short-term climatic variations.

The zone of ____________________ is the portion of a glacier where additions exceed losses.

What are glaciers? How are they as agents of erosion and deposition?

Glaciers are geologically important because they erode,transport,and deposit so much material.

The present glacial landscapes mainly formed during an Ice Age that lasted from years to years ago.

How does the water bound in glaciers eventually reenter the hydrologic cycle?

A glacier that is now longer flowing is called a(n)____________________ glacier.

What evidence of their passage do glaciers leave on bedrock?

The terms continental glacier and ice sheet are synonymous.

Straight scratches on rock surfaces created by glacial abrasion are known as: