Landforms of Glaciation - Civil Services Preparation Online! UPSC & IAS Study Material

Landforms of Glaciation

by Devender

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There are only 2 major ice caps present in the world today that are - Antarctica & Greenland. However, there are many highlands above the snowline surviving in the world.

Landforms of Glaciation

  • The peaks of the loftiest mountains projecting above the ice surface are known as Nunataks
  • The ice from ice caps escapes in all directions as glaciers
  • When this ice reaches the bottom of the sea, it floats as ice shelves over polar waters
  • When these shelves break into individual blocks, they are called icebergs
  • Only 1/9th of the iceberg's mass is visible above the surface when the iceberg floats oversea
  • They diminish in size when reaching warm waters & eventually melted, dropping the rock debris that was frozen inside them on the sea bed. The Permanent snowfield is sustained by heavy snowfall in winters & ineffective snow melting & evaporation in summers as part of snow that melts during the day is refrozen during the night.

  • This refreezing process repeats until it forms a hard, granular substance known as neve or firn
  • Neve of the upland snowfield is drawn towards the valley below due to gravitational force that marks the beginning of the flow of glacier (river of ice).


  • Glaciers
  • They normally assume the shape of a tongue, broadest at the source & becoming narrower downhill. Glaciers are not liquid but still, moves gradually under the continual pressure from the snow accumulated above.

  • The rate of movement is greatest in the middle where there is little obstruction
  • The sides & bottom are held back by the frictions due to valley sides & valley floors

If a row of stakes is planted across a glacier in a straight line, they will eventually take a curved shape down the valley, showing that the glacier moves faster at the center than at the sides.

Types of Glaciers

There are 3 types of glaciers that are:

1 Piedmont Glacier

These are found at the foot of the mountain ranges, several glaciers may converge to form an extensive ice mass.

2 Cirque Glacier

These are formed in a cirque, bowl-shaped depression on the side of or near mountains. Snow and ice accumulation in corries often occurs as the result of avalanching from higher surrounding slopes.

3 Valley Glacier

The streams of flowing ice which are confined within steep-walled valleys, often following the course of an ancient river valley.



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