Question 1

How long ago was the glacial maximum of the last Ice Age?

Accepted Answer

The glacial maximum of the last Ice Age, also known as the Last Glacial Maximum (LGM), occurred approximately 20,000 years ago.

Question 2

Diamond- bearing kimberlites occur in the Northwest Territories, Saskatchewan and Ontario. What type of glacial deposit would be most useful for tracing kimberlite cobbles and minerals directly to their bedrock source area?

Accepted Answer

End or ground moraines formed by a continental ice sheet are most useful for tracing kimberlite cobbles and minerals directly to their bedrock source area because these deposits are left directly by the melting ice, often in a broad swath that can directly trace back to the source area, unlike the more localized or specific conditions required for the formation of lateral or medial moraines, kames, and kame terraces.

Question 3

A drumlin is usually made of_________ _.

Accepted Answer

Drumlins are typically composed of glacial till, which is an unsorted mixture of clay, silt, sand, gravel, and boulders deposited by glacial ice.

Question 4

Upon what evidence did Agassiz base his ice age theory?

Accepted Answer

Agassiz based his ice age theory on observations of glacial landscapes in the Swiss Alps that extended far beyond the current ice fronts, indicating that glaciers had once been much more extensive.

Question 5

Prior to its sudden emptying down the St. Lawrence around 11,000 years ago, ________was the largest lake in North America.

Accepted Answer

Lake Agassiz was the largest lake in North America before it drained into the St. Lawrence River around 11,000 years ago, significantly impacting global water levels and climate patterns.

Question 6

All of the following descriptions apply to stratified drift (not till) except for___________ .

Accepted Answer

Stratified drift is characterized by sediments that have been sorted and deposited by glacial meltwater, not directly by the ice itself. Rock flour deposited directly from advancing ice describes till, not stratified drift.

Question 7

What glacial landform is responsible for a large portion of the water resources for greater metropolitan Toronto?

Accepted Answer

The Oak Ridges Moraine is a significant glacial landform that acts as a natural water filtration and storage system, providing a large portion of the water resources for the Greater Toronto Area. Its composition of sand and gravel allows for the accumulation and natural filtration of rainwater, which then replenishes groundwater supplies crucial for the region.

Question 8

What type of moraine is formed by the merging of two lateral moraines at a junction of two valley glaciers?

Accepted Answer

Medial moraines are formed when two glaciers merge and the debris on the sides of each glacier (lateral moraines) combine to form a moraine in the middle of the merged glacier.

Question 9

A(n)__________ is likely to host a large stream with a waterfall or steep rapids today.

Accepted Answer

Hanging valleys are formed when a smaller glacier flows into a larger one, and after the glaciers melt, the smaller valley is left hanging above the main valley. This often results in waterfalls or steep rapids as streams or rivers flow from the hanging valley down to the floor of the main valley.

Question 10

During the peak of the last Ice Age, continental land area was larger and you could have walked across the English Channel because_________ .

Accepted Answer

During the last Ice Age, a significant amount of the Earth's water was locked up in massive ice sheets, leading to a global sea level that was about 100 meters lower than it is today. This exposed land that is now underwater, including the area of the English Channel, allowing for the possibility of walking from what is now England to France.

Question 11

Which of the following sediment types is not glacial drift?

Accepted Answer

Pleistocene deep sea oozes are not considered glacial drift because they are marine sediments formed on the deep ocean floor, unrelated to the direct action of glaciers or ice sheets, which characterizes glacial drift.

Question 12

An erratic is made of__________ .

Accepted Answer

An erratic is a large rock or boulder that has been transported and deposited by a glacier, often far from its original location. It is typically made of rock, not sand, gravel, mud, or till.

Question 13

When did the great southern hemisphere glaciation of Pangaea occur?

Accepted Answer

The great southern hemisphere glaciation of Pangaea occurred during the Permian Period, which is part of the Paleozoic Era, lasting from about 299 million to 251 million years ago. This period is known for significant climatic changes, including extensive glaciation in the southern part of Pangaea.

Question 14

Which one of the following applies to a valley glacier that lengthens (extends its terminus downslope) over a span of many years?

Accepted Answer

When a valley glacier lengthens over many years, it indicates that accumulation (the addition of snow and ice) exceeds wastage (the melting and sublimation of ice). This net gain in ice mass allows the glacier to extend its terminus downslope.

Question 15

Headward erosion by alpine glaciers on two sides of a mountain ridge can remove enough rock to intersect forming a pass called a____________ .

Accepted Answer

A col is a pass formed when headward erosion by alpine glaciers on two sides of a mountain ridge intersects, removing enough rock to create a gap or pass.

Question 16

Which process occurs where a glacier enters the sea?

Accepted Answer

Calving is the process where chunks of ice break off at the terminus of a glacier, often into the sea, forming icebergs.

Question 17

A __________forms when stagnant, glacial ice melts after being buried by till or outwash.

Accepted Answer

A kettle forms when a block of ice from a glacier becomes buried in glacial drift and then melts, leaving behind a depression that often fills with water, creating a kettle lake.

Question 18

The oldest extensive glacial deposits preserved in: Finland, North America, South Africa, and Western Australia occurred______ years ago, which_____ took for evidence of his _________hypothesis.

Accepted Answer

The oldest extensive glacial deposits, found in regions including Finland, North America, South Africa, and Western Australia, date back to approximately 2.3 billion years ago. These deposits were used by Paul Hoffman as evidence for his Snowball Earth hypothesis, which suggests that the Earth was once almost entirely covered in ice.

Question 19

How do most icebergs in the North Atlantic Ocean originate?

Accepted Answer

Most icebergs in the North Atlantic Ocean originate from the calving of large tidewater glaciers on Greenland, rather than from Antarctica or the Arctic Ocean.

Question 20

What was the most far reaching effect of the Ice Age on the world's oceans?

Accepted Answer

During the Ice Age, significant amounts of the Earth's water were locked up in glaciers and ice caps, leading to a drop in global sea levels by about 100 meters. This had a profound effect on the world's oceans, exposing continental shelves and connecting landmasses that are now separated by water.

Quiz 9: Crustal Deformation