When two valley glaciers join, the merging of their lateral moraines produces which feature?
- A.Terminal moraine
- B.Medial moraine
- C.Ground moraine
- D.Esker
Correct answer
Explanation
The correct answer is B, a medial moraine. Debris falling from the valley sides collects along each edge of a glacier as a lateral moraine; where a tributary glacier joins the trunk glacier, the inner lateral moraine of each merges into a single dark stripe of rock waste that runs down the middle of the combined ice, and that stripe is the medial moraine. Option A is wrong because a terminal or end moraine is the arc of debris dumped across the snout where the ice stops advancing, and it often dams a lake. Option C is wrong because ground moraine is the sheet of till spread under the whole glacier and left behind as an undulating plain. Option D is wrong because an esker is a long winding ridge of sand and gravel laid by a meltwater stream flowing in a tunnel under the ice, so it is a fluvioglacial, not a moraine, form.
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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