As mentioned earlier, glacial depsists consist of a mixutre of dirt, rock flour and sub angular rock boulders which are often striated, unstratified and unassorted. The deposits are moraines.

(i) Drumlin:

A typical ground moraine is termed as drumlin which is an elongated, oval shaped hill. The hill ranges in height from a few meters upto 50 meters and in length from half a kilometer to 3 kilometers. The shape is that of inverted spoon or egg. The longer axis is parallel to the direction of glacial movement. The tapering end points towards the direction of flow, that is, opposite to that of roches moutonnee which are erosional in contrast to depositional nature of drumlins. The down hill side of the drumlin is smooth and gently sloping. The drumlins generally occur in swarms / groups; topography is often termed as basket of eggs topography.

(ii) Knob and Basin, Kame and Kettle:

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These are featuers associate! With moraines. In the first type, the knobs or hummocks consist o unstratified drift and in the second type, the larger kames or knob consist of stratified sand and gravel. The basins are depression within the interspaces between the knobs. Kettles, filled in water, form kettle lakes.

Fluvio-GIacial Land Forms:

Melting of glacial ice releases Lar volume of water that flows down the slope. A number of land forms produced due to the combined action of glacial ice and melt water. There are termed as Glacio-fluvial forms.

(i) Out-wash Plain:

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The rock debris carried by the glaciers a transported by the streams and are immediately deposited formin fans and deltaic land. This plain land is termed as out wash plain. Times, the deposits occuring on the valley floors extend downwa* and are termed as valley trains. In some cases, blocks of ice a buried beneath the out wash plain and after melting of depressions are formed. These are termed as kettles. Out wash plains pitted with depressions are known as pitted out wash plains.

(ii) Kames, Kame Terraces:

Kames are small mounds composed of poorly stratified sediments formed by ice melt water. Kame terrace are fillings of glacial troughs and deposits between a glacier and the side wall. These are poorly sorted.

(iii) Eskers:

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These are long, narrow and smooth surfaced ridges of low height composed of stratified sand and gravel similar to later- moraines. Commonly, this landform is produced when the ice is stagnant and hence eskers are commonly formed in areas where ice stands for a considerable time and, thus, are common in continental glaciated regions.

(iv) Glacio – Lacustrine Plain:

Lakes are common in glaciated areas. They are formed in many ways; by glacial erosion, melting of ice and by other processes. These are temporary features of the earth’s crust and are quickly filled in with sediments forming lacustrine plains in glacial regions. The coarse silt is quickly deposited in the lakes, while the fine sediments like mud settles afterwards. These alternate depositon of coarse silt and mud gives rise to varves and the rock, thus formed, is varvite. One set of course and fine material forms usually in one year.

Pleistocene Glaciations: The knowledge on glaciers and glacial landforms would be incomplete without a little idea on the Pleistocene Gl.vial Epoch. It is believed that more than one fifth of the land surface o. ihe globe was covered with snow and ice during this period. During this great Ice Age, four major advances and four retreats of the continental glaciers have been recognized.

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The glacial epoch began nearly one million years ago with alternation of glacial and interglacial periods. The recent period, whether interglacial or post – glacial is a great question.

The retreat of the last glaciation is estimated to be nearly 25,000 years ago. Most of the present day landscapes, especially those in the northern hemisphere are the products of this Great Ice Age. During this period, the sea level fli.Ptuated appreciably as evidenced by the occurrences of marine fossils, coral reefs and marine strandlines. Little of the earth’s topography is older than Tertiary and most of it not older than Pleistocene, is a general concept of geomorphology. Most of the well glaciated regions show youth topography.