Describe the Landscapes formed by the Erosion of Glaciers.

Due to the erosion of glaciers, various features are formed on mountains.

1 ) Ice Depressions –

When glaciers move down from high mountain areas, they create depressions on the mountain slopes. These depressions gradually become deep troughs. Over time, these troughs become so deep and wide that glaciers are formed and nourished by them. This is called a corrie in Scotland, a cirque in France, a kar in Germany, a cwm in Wales, and a cirque in Scandinavia. The Governo Trench in the Pyrenees Mountains is a famous example of a glacier formed by this process.

When viewed from a distance, a corrie presents a valley-like semi-circular theater. It is surrounded by high-low peaks with a steep gradient. The shape of a snow-free corrie is like an armchair.

American scholar Martwj Johnson shed light on their origin. Johnson argued in 1904 that the cirque is formed in place of a wide fissure or square horn. It occurs at the top of a glacier. Glacial water enters the fissure and causes chemical erosion of the underlying rocks. This is called the Aargashringa theory.

However, some of these features are found at significant heights in places without glaciers. Based on this, Mr. Davis presented an amendment in 1904 with a suitable hypothesis. According to him, in summer, the water obtained from the melted snow of the glacier enters the joints and crevices of the rocks. When it freezes at night, its volume increases, causing the rocks to disintegrate. This huge pit is called a cirque. These pieces are removed by the slow movement of the glacier. This process is called snow subsidence.

In this way, the hollow area becomes bigger due to snow erosion. The rocks falling from the peaks start collecting and making the dust bed deeper. The glacier flowing from this depression appears to be hanging in such a way that these depressions are the source of glaciers. When the glacier melts and gets destroyed due to an increase in heat, the depression takes the form of a lake, which is called a tarn. These features make the mountain view captivating and attractive.

The wall of the vertical surface is uneven due to erosion by frost on the walls of the cavity, but its production becomes smooth due to wear and tear. Tarns are found in Finland. Sometimes these pits are long, and these lakes are called finger lakes.

Ice erosion occurs when glaciers lose their mass and become smaller. This causes them to melt, which makes them less dense. As this happens, they get pushed out into valleys and onto mountaintops where they can no longer stay put under their own weight (they’re too heavy) but instead break off from the glacier itself and float around on top of it until eventually falling down into some kind of river or stream system where they will eventually get deposited into an ocean somewhere else on Earth’s surface!

One thing you might have noticed about glaciers is that they’re not very colorful. This is because the ice is clear, and light can pass through it easily. If you were walking on top of a glacier and could see through it, your view would be pretty much what you’d expect: the blue sky above and white snow below!

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2 ) Arête –

Two ice caves that meet at the same angle and have a wall at their top erode to form a sloping crested ridge. These are called arêtes, a word derived from the French language. When the ice depressions on opposite sides of a mountain become opposite to each other and experience continuous top erosion, a solid pyramid-shaped peak is formed over time. This is called an arête, with examples including Matterhorn and Jungfrau in the Alps (Switzerland) and the Shivling near Badrinath on the Himalayan mountain. An arête joins the peak.

When arêtes are eroded continuously at their apex, a large ledge is formed and a passage is opened, connecting both glaciers. This passage is called a col (short for col de passage).

An arête is a sharp and narrow ridge of rock formed by the intersection of two glaciers. It is often found in high-altitude areas where two glaciers meet at a steep angle, and their ice flows down the slope to form a sharp ridge of ice.

Arêtes are usually steep and narrow, but they can also be quite long with many hanging valleys on either side. If you look closely at an arête, you will see that it has been carved out by two glaciers meeting at an angle and flowing down toward each other over time.

3 ) U-Shaped Valley –

Glaciers do not create new valleys; instead, they modify previously formed river valleys. As a result, the valleys widen, and the banks become almost vertical. In this way, the shape of the glacier valleys becomes like the letter U in English. These valleys become deep, and the bottom becomes broad and flat. Their banks are steep and concave, and the floor of this valley is visible from the upper part.

The development of the valley depends on the composition of the rocks and the stage of development of the glacier. A typical example of this type of valley is Yosemite Valley in the United States of America. According to the British Physicist John Tyndall, “These valleys were formed entirely by glaciers, in whose construction there is no special cooperation of water.” However, there is another opinion among scholars. Some reject Tyndall’s opinion and argue that the initial formation of U-shaped valleys is formed by flowing water, and they are later fully developed by glaciers.

A U-shaped valley has a flat floor, steep sides, and a wide mouth. It is formed by the erosion of glaciers. U-shaped valleys are found in the High Himalayas, where they were formed by glaciers that wore away the tops of mountains.

4 ) Suspended valley –

glaciers flow through ancient river valleys. The large glaciers of the main valley deepen their beds more quickly than the glaciers of the tributary valleys. As a result, a steep gradient is created at the confluence of the main river and the tributary. When the snow melts, the water of the tributary river starts falling into the main river in the form of a waterfall. The best example of the main river valley is Yosemite Valley in the Sierra Nevada Mountains of California. Norway, Chile. Fiords of countries like Alaska are probably the gateways of such valleys.

Due to the depth of the bottom of the main valley, some scholars argue that it is not a glacier, but an ordinary river. According to this, the main valley is rapidly deepened by the river, while the tributary valleys are covered by glaciers and protected from erosion. All the tributaries of the Reuss river in the Sand Gobai pass in the Alps are of this type.

A suspended valley is a valley that has been formed by erosion. The glacier erodes the rock, forming a channel between two higher ridges. In this way, it can create an open space where water flows into the earth instead of being trapped by glaciers at its base.

When you think of a suspended valley, you may be thinking of the Himalayas or other mountainous regions in Asia where there are many hanging valleys that have been formed from glaciers melting away over thousands of years.

In this case, the valley is created when water flows through the ground, eroding it and leaving behind a channel. This can happen in two ways: If the water flows quickly enough and there’s not much sediment to get in its way, it will carve out a narrow channel called a “V-shaped” canyon. The walls of this canyon are steep and vertical because they were carved out by fast-running water hanging valleys are often steep and narrow, with sheer walls that can be up to 1,500 meters high. They have a rounded floor, which is formed by the melting ice at the bottom of the valley. Hanging valleys are formed when glaciers retreat or melt away from their sides..

5 ) Bhedpeeth –

Rock glaciers do not flow in zigzag routes. Often, they make obstacles located in their way smaller and smoother by biting and rubbing against them. This results in the formation of low circular mounds in the valley bottom. Small hills are formed in the valleys of the Alps due to the erosion of Dolomite rocks, and from a distance, these mounds resemble sitting sheep. Sir Caesar named them Bhedpeeth Shail, which means sheep-shaped shell in French. Bedrock is also formed when softer rocks surround harder rocks on the valley floor. The part through which the glaciers move has a normal slope and is called the leeward side, while the other side is steep and bumpy. Due to the breaking of jointed rocks, it becomes like a step. Bhedpeeth rock is found in areas where the rocks are more resistant, i.e., neither the rocks are soft nor are they residual forms before the cover that have been altered by glaciation.

Bhedpeeth is a depression formed by the ice of a glacier. It is a wide, flat valley that is shaped like a ‘U’. This type of valley can be found in the Himalayan Mountains of India and Nepal. The term Bhedpeeth means “the mouth” or “the opening” in the Nepali language, as it resembles an open mouth that leads to other areas of glaciers.

Hanging valleys form when large sheets of ice melt away from their edges and leave behind empty spaces between them. These empty spaces are called hanging valleys because they hang down from their parent body (i.e., the glacier).

6 ) Fjord –

One of the features of erosion by glaciers is that glaciers cut their valleys below sea level because, in high latitudes, the glaciation of valleys extends to the sea. This is called over-deepening by glaciers. Fjords are formed by glacial erosion, and they have more depth towards the coast, while the sea remains shallow and farther away. Fjords are valley depressions cut through the middle of the rocky part projecting to the edges of the steep slope. They are particularly found on the coasts of Norway, Greenland, Labrador, Alaska, Chile, and New Zealand. During the Ice Age, these valleys became wider and deeper.

In a sense, all fjords are the result of erosion – the wind and glaciers have worn down mountains and cliffs over time. A fjord is just one type of glacier-formed landscape formed by glacial processes, which can be distinguished from other types by its unique shape and structure. Some examples include:

  • The Norwegian Fjord – The most well-known example of this type of formation occurs in Norway, where it extends for hundreds of miles along its coastlines, including several deep valleys. These valleys were carved out by glaciers during past ice ages as they swept across Europe millions of years ago.
  • Fram Strait Fjord – Another popular example lies between Canada’s British Columbia province with an area of around 100 square miles at its widest point. This particular feature was formed when two large islands collided during an earthquake centuries ago, which took place somewhere near present-day Victoria City.

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