Some important MCQs Related to Geological works by Glacier With Explanations -4

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41. What is the process of regelation in glacial movement?

A) Ice melting under pressure and refreezing when the pressure is released
B) The sliding of a glacier over a lubricated base
C) The internal deformation of glacier ice
D) The deposition of sediments by meltwater

Answer: A) Ice melting under pressure and refreezing when the pressure is released
Explanation:
Regelation occurs when ice melts under high pressure at the glacier’s base, flows around obstacles, and refreezes when the pressure is reduced. This process contributes to glacier movement over uneven terrain.


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42. Which term describes the sediment deposited directly by a glacier without sorting by water?

A) Glacial drift
B) Glacial till
C) Outwash
D) Stratified drift

Answer: B) Glacial till
Explanation:
Glacial till consists of unsorted, unstratified debris deposited directly by a glacier. It includes a mix of clay, silt, sand, gravel, and boulders.


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43. What is the difference between an arête and a horn?

A) An arête is a sharp ridge, while a horn is a pyramid-shaped peak
B) An arête is depositional, while a horn is erosional
C) An arête forms in valleys, while a horn forms in flat regions
D) An arête forms below glaciers, while a horn forms above glaciers

Answer: A) An arête is a sharp ridge, while a horn is a pyramid-shaped peak
Explanation:
An arête forms when two glaciers erode opposite sides of a ridge, while a horn forms when three or more cirques erode a mountain peak.


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44. What are striations, and what do they indicate?

A) Layers in ice that show annual snowfall patterns
B) Grooves in bedrock that indicate glacial movement direction
C) Ridges formed by meltwater streams
D) Depressions in the glacier surface caused by melting

Answer: B) Grooves in bedrock that indicate glacial movement direction
Explanation:
Striations are scratches or grooves on bedrock caused by rocks embedded in the glacier. They provide evidence of the glacier’s movement direction.


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45. Which of the following is a recessional moraine?

A) A ridge of debris at the furthest extent of a glacier
B) A ridge of debris marking pauses during glacier retreat
C) A flat plain formed by glacial meltwater deposits
D) A steep-sided valley carved by a glacier

Answer: B) A ridge of debris marking pauses during glacier retreat
Explanation:
Recessional moraines form behind the terminal moraine and represent locations where the glacier temporarily halted during its retreat.


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46. What is a tarn?

A) A depositional feature formed by glaciers
B) A small mountain lake formed in a cirque
C) A ridge left by retreating glaciers
D) A steep valley formed by glacial erosion

Answer: B) A small mountain lake formed in a cirque
Explanation:
A tarn is a small lake that forms in a cirque after a glacier retreats. It results from the melting of glacier ice in the depression.



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47. What is the primary factor that determines whether a glacier advances or retreats?

A) Ice thickness
B) Snowfall in the accumulation zone
C) Balance between accumulation and ablation
D) Latitude of the glacier

Answer: C) Balance between accumulation and ablation
Explanation:
A glacier advances when accumulation exceeds ablation (melting and sublimation) and retreats when ablation exceeds accumulation.


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48. What is a fjord?

A) A deep, glacially carved valley filled with seawater
B) A lake formed by glacial meltwater
C) A steep-sided ridge formed by glacial erosion
D) A large flat area of glacial deposits

Answer: A) A deep, glacially carved valley filled with seawater
Explanation:
Fjords are U-shaped valleys carved by glaciers that are later flooded by seawater due to rising sea levels after the glacier retreats.


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49. What is a drumlin?

A) A steep, narrow ridge formed by glaciers
B) A teardrop-shaped hill made of glacial till
C) A hollow depression left by a melting ice block
D) A lake formed by glacial activity

Answer: B) A teardrop-shaped hill made of glacial till
Explanation:
Drumlins are streamlined hills of glacial till that indicate the direction of glacier movement, with the tapered end pointing downstream.


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50. How does frost wedging contribute to glacier formation?

A) By increasing the accumulation of ice at the glacier terminus
B) By breaking down rocks, adding debris to the glacier
C) By creating crevasses in the glacier surface
D) By compacting snow into glacial ice

Answer: B) By breaking down rocks, adding debris to the glacier
Explanation:
Frost wedging occurs when water in cracks freezes and expands, breaking rocks into smaller pieces. This debris is often incorporated into glaciers.

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51. What is an icefall?

A) A frozen waterfall formed by glacier meltwater
B) A steep section of a glacier where ice flows rapidly
C) A large crack in a glacier caused by melting
D) A lake formed by glacier retreat

Answer: B) A steep section of a glacier where ice flows rapidly
Explanation:
An icefall is a

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