A valley eroded by a glacier typically has which cross-section?
- A.V-shaped
- B.U-shaped
- C.Gorge-like and narrow at the top
- D.Saucer-shaped
Correct answer
Explanation
The correct answer is B, U-shaped. A glacier fills the whole floor of a valley and erodes its sides as well as its bed, so it widens and deepens the valley into a trough with a broad flat floor and steep straight walls, which in section looks like the letter U. Option A is wrong because the V-shaped valley is the work of a river, which cuts chiefly downward along a narrow channel in its youthful stage, and this contrast between the river V and the glacial U is the most frequently asked point in this chapter. Option C is wrong because a gorge or canyon is also a river form, cut in hard rock or in an uplifted plateau. Option D is wrong because no glaciated valley is saucer-shaped; the saucer form belongs to features such as a deflation hollow in a desert.
Read the full article: Glaciers of India and the World: Notes for Exams
Practice Questions
View allWhich is the longest glacier in India?
- A.Gangotri
- B.Siachen
- C.Zemu
- D.Bara Shigri
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Its meltwater feeds the Nubra river, a tributary of the Shyok, which joins the Indus.
Read the full explanation →Gaumukh, the snout of the Gangotri glacier, is the source of which river?
- A.Alaknanda
- B.Bhagirathi
- C.Yamuna
- D.Mandakini
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The Gangotri glacier ends in a snout shaped like the mouth of a cow, which gives it the name Gaumukh, and the stream that issues from it is the Bhagirathi.
Read the full explanation →Which is the largest glacier in the world?
- A.Fedchenko glacier
- B.Lambert glacier
- C.Siachen glacier
- D.Aletsch glacier
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Antarctica holds the greater part of the ice of the earth, so its outlet glaciers dwarf those of other continents.
Read the full explanation →The Fedchenko glacier, the longest glacier outside the polar regions, lies in which mountain system?
- A.The Andes
- B.The Pamirs
- C.The Alps
- D.The Rockies
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The Pamir knot is the node where the Himalaya, the Karakoram, the Hindu Kush, the Kunlun and the Tian Shan ranges meet, and the Fedchenko glacier, running for roughly seventy-seven kilometres, is the longest glacier found anywhere outside the Arctic and the Antarctic.
Read the full explanation →A small lake occupying a cirque or corrie hollow in a glaciated mountain is called a:
- A.Tarn
- B.Kettle lake
- C.Fjord
- D.Lagoon
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A cirque, also called a corrie, is the armchair-shaped hollow that a glacier scoops at the head of its valley by plucking and abrasion; when the ice melts, water collects in the rock basin and the small round lake so formed is a tarn.
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