1. Cirques:
These are circular depressions formed by plucking and grinding on the upper parts of the mountain-slopes. These are also known as ‘corries or amphitheatre’.
2. Arete:
This name is applied to the sharp ridges produced by glacial erosion. Where two cirque-walls intersect from opposite sides, a jagged, knife-like ridge, called an ‘arete’ results. It is also known as ‘comb’ or ‘serrate-ridge’.
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3. Horn:
Where three or more cirques grow together, a sharp-pointed peak is formed by the intersection of the aretes. Such peaks are known as ‘horns’.
4. Col:
Where opposed cirques have in ersected deeply, a pass or notch, called a ‘col’ is formed.
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5. Glacial-trough:
Glacier flow constantly deepens and widens its channel so that after the ice has finally disappeared there remains a deep, steep walled, ‘U’-shaped valley, known as glacial trough.
6. Hanging valley:
Tributary glaciers also carve ‘U’-shaped troughs. But they are smaller in cross-section, with floors lying high above the floor-level of the main-trough, i.e., main glacial valley. Such valleys are called hanging-valleys.
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7. Fiords:
When the floor of a glacial trough open to the sea lies below sea-level, the sea-water will enter as the ice-front recedes producing a narrow estuary, known as a ‘fiord’ or fjords’.
8. Tarns:
The bed-rock is not always evenly excavated under a glacier, so that floors of troughs and cirques may contain rock-basin and rock-steps. Cirques and upper parts of troughs thus are occupied by small lakes, called tarns.
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Depositional features of valley-glaciers:
Deposition by a glacier takes place when the ice begins to melt and the glacier slows down and vanishes, losing its transporting power. The uncertified, unsorted debris dropped more or less in a random fashion by glaciers form deposits known as morains.
Three types of moraines are known, lateral, medial or median, and terminal or end. These three types are differentiated on the basis of their location in the valley.
(a) Lateral-moraine:
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Deposits of ridge-like pattern formed along the margins of the glaciated valley are known as lateral moraines.
(b) Medial-moraine:
It results due to coalescence of two lateral moraines, where two ice streams join.
(c) Terminal-moraine:
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These are accumulation of rock-debris at the terminus of a glacier.
(d) Recessional moraine:
Where glacier retreats in a halting manner, a series of concentric moraines is formed, known as ‘recessional moraines’.
Topography of continental glaciations’:
Like valley glaciers, the continental glaciers proved to be highly effective eroding agent. But continental glacier erodes only by plucking and rasping methods, but erosion process, like avalanching is absent in case of continental glaciers.