Due to the erosion of glaciers, the following features are formed on the mountains-
1 ) Ice depressions – When glaciers descend from high mountain areas, they create many depressions on the mountain slopes, which gradually grow into deep depressions. Over time, these troughs become so deep and wide that glaciers are born 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.
- Describe the Cycle of Erosion Given by Penck.
- Explain the Erosional Topographies Formed by Wind.
- Give an Analytical Description of the Landforms Formed by River Erosion.
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 has 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.
But all are found at sufficient height in places without class beetles. On this basis, Mr. Davis presented an amendment in 1904 with a suitable hypothesis. According to them, in summer, the water obtained from the melted snow of the glacier enters the joints and crevices of the rocks and when it freezes at night, its volume increases. This action continues continuously. Due to this, the rocks get disintegrated. 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 and in this, the snow 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 the increase in heat, the depression takes the form of a lake, it is called a tarn. Due to these, the mountain view becomes captivating and attractive.
The wall of the vertical surface is uneven due to erosion in the 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 these lakes are called finger lakes.
Ice erosion occurs when glaciers lose their mass and become smaller, causing them to lose more mass than they take in. This causes them to melt, which also causes them to become less dense as they melt. 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 it 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, so 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!
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. This word is derived from the French language. When the ice depressions on the different sides of a mountain become opposite to each other and there is continuous top erosion, then in course of time a solid pyramid-shaped peak is formed. This is called an arête, examples are Matterhorn and Jungfrau on the Alps mountain (Switzerland). The Shivling near Badrinath on the Himalayan mountain is also made in the same way. An arête joins the peak.
When the arêtes are cut down by continuous apex erosion, a huge ledge is formed and a cross passage is opened. Here both glaciers seem to be connected. This is called a col (short for col de passage)
Arête is the sharp, 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 very steep and narrow; 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, but only 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. Its banks are steep and concave. Therefore, 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 development stage 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 later they are fully developed by glaciers.
A U-shaped valley with a flat floor, steep sides, and a wide mouth. It is formed by the erosion of glaciers. The U-shaped valleys are found in the High Himalayas, where they were formed by glaciers that wore away at the top 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 through zigzag routes. Often, they make the obstacles located in the way smaller and smoother by biting and rubbing them. In this way, low circular mounds are formed in the valley bottom. As a result of the erosion of the Dolomite rocks of the Alps, small hills are formed in their valleys. These mounds look like sitting sheep from a distance. Therefore, Sir Caesar gave them the noun of Bhedpeeth Shail. This French word means sheep-shaped shell. Bedrock is also formed when softer rocks surround the harder rocks on the valley floor. The part of them through which the glaciers move is of normal slope and is called the leeward side and the other is called the leeward side. it was steep and bumpy And due to the breaking of the jointed rocks, it becomes like a step. The Bhedpeeth rock is found in the Due to this, they become smooth, striped, and padded. The reason for their formation is that the rocks are more powerful, that is, neither the rocks are hard, nor are they the residual forms before the cover, which have been changed by the 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 valley can be found in the Himalayan Mountains of India and Nepal.
Bhedpeeth means “the mouth” or “the opening” in the Nepali language, as it resembles an open mouth that leads to other areas of glaciers.
The hanging valleys form when large sheets of ice melt away from their edges and leave behind empty spaces between them; in this case, these empty spaces are called hanging valleys because they hang down from their parent body (i.e., the glacier).
6 ) Fiord – One of the features of erosion by glaciers is that glaciers cut their valley below the sea level because in high latitudes the glaciation of valleys extends to the sea. This is called over-exploitation by glaciers. Fiords are formed by glacial erosion and erosion. In these, more depth is found with the help of the coast and shallow sea remains far away. These are valley depressions cut through the middle of the rocky part projecting to the edges of the steep slope. Fiords are especially 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 fiord is just one type of glacier-formed landscape formed by glacial processes, which can be distinguished from other types by their 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 upon millions of years ago!
- Fram Strait Fiord – 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 together during an earthquake centuries ago–it took place somewhere near present-day Victoria City which you might recognize if you’ve ever watched any TV shows set there before!