Question 1

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

Accepted Answer

Firn is the intermediate product in the transformation of snow to glacial ice. It is compacted snow that has survived one or more summer melt seasons, but has not yet been fully transformed into solid ice.

Question 2

________ involves the internal flowing of ice under,generally,solid conditions,via the breaking and reforming of chemical bonds.

Accepted Answer

Plastic deformation involves the internal flowing of ice under solid conditions through the breaking and reforming of chemical bonds.

Question 3

Which of the following scenarios would lead to glacial advance during a time of global warming?

Accepted Answer

A glacier in a depression that lies in shadows most of the day may accumulate more snow and ice due to reduced melting caused by less direct sunlight. This can lead to glacial advance even during a time of global warming. The other options do not necessarily lead to glacial advance during global warming.

Question 4

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

Accepted Answer

The answer of Valleys carved by glaciers tend to be...

Question 5

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

Accepted Answer

The answer of Glacial ice exhibits ________ behavior near the...

Question 6

Which of the following images shows the oldest snow?

Accepted Answer

The answer of Which of the following images shows the...

Question 7

Cirques and horns are features associated with ________.

Accepted Answer

Cirques and horns are features commonly formed by the processes of mountain glaciation, including the accumulation and movement of ice in high-altitude regions. Continental glaciation refers to the type of glaciation that occurs over large landmasses and across entire regions, which typically produces different landforms such as drumlins, eskers, and moraines. Glacial outwash deposits and loess deposits are not directly related to the formation of cirques and horns.

Question 8

Glaciers that move via basal sliding can often undergo surges in which they move at a much faster rate than normal because they ________.

Accepted Answer

Glaciers that move via basal sliding are those that have minimal frictional contact with bedrock. This means that they can undergo surges in which they move at a much faster rate than normal, as the lack of friction allows them to easily slide over the bedrock. Choices A and D are incorrect, as plastic deformation and volume do not play a significant role in the occurrence of surges. Choice B is incorrect, as glaciers do not float on a cushion of air like avalanches.

Question 9

________ glaciers cover vast areas of land,whereas ________ glaciers are restricted to mountaintops.

Accepted Answer

Continental glaciers are massive ice sheets that cover large land areas and can be over 1.5 million square kilometers in size. Alpine glaciers, on the other hand, are smaller and more common in mountainous regions.

Question 10

Glacial ice forms when snow accumulates in large enough volumes to compact and force ________ out and ________ the ice crystal size.

Accepted Answer

Glacial ice forms when snow accumulates, compacting the snow and forcing air out, which increases the size of the ice crystals.

Question 11

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

Accepted Answer

Glacially carved landscapes are characterized by features such as cirques, arêtes, horns, and striations, which are formed by the erosive action of glaciers.

Question 12

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

Accepted Answer

The answer of Currently,almost all the glaciers on Earth are...

Question 13

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.On what real-life geologic event was this part of the movie based?

Accepted Answer

The movie's flood event is based on the destruction of Glacial Lake Missoula, which caused massive floods known as the Missoula Floods during the last ice age.

Question 14

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

Accepted Answer

Glaciers currently cover about 10% of the world's land surface, mainly in places like Greenland and Antarctica.

Question 15

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

Accepted Answer

A glacier will advance if the rate of accumulation (snowfall, ice buildup) is greater than the rate of ablation (melting, sublimation, calving), which means that the glacier is losing mass at a slower rate than it is gaining mass. Subsidence, erosion, and uplift do not determine the direction of a glacier's movement.

Question 16

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

Accepted Answer

The polar ice caps on Mars are large ice sheets covering the polar regions of the planet, similar to the continental glaciers found on Earth.

Question 17

________ are formed when one glacier beheads another.

Accepted Answer

Hanging valleys are formed when a smaller tributary glacier is left hanging above the main U-shaped valley after it has been deepened or widened by a larger glacier. This occurs when the smaller glacier is unable to erode the valley floor to the same depth as the larger glacier, resulting in a steep drop-off or waterfall at the hanging valley's mouth.

Question 18

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?

Accepted Answer

Striations are fine scratches or grooves on the surface of rocks that are caused by the movement of glaciers. Glaciers have immense weight and force, and they can scrape and scratch the bedrock and other surfaces they move across. Therefore, if you encounter a surface with fine scratches, it is likely that these are glacier striations.

Question 19

The central glacier in the figure below once stretched all the way to the farthest ground moraine.What type of glacier was it?

Accepted Answer

The answer of The central glacier in the figure below...

Question 20

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

Accepted Answer

As pressure increases, the ice becomes more ductile and is able to deform plastically instead of breaking brittlely. At depths of greater than 60, the pressure is high enough for the ice to deform plastically. None of the other choices directly relate to the transition from brittle to ductile behavior.

Quiz 18: Amazing Ice: Glaciers and Ice Ages