erosion of a river valley takes place in which course

What is Valley erosion?

Valley erosion is the process in which rushing streams and rivers wear away their banks, creating larger and larger valleys. The Fish River Canyon, in southern Namibia, is the largest canyon in Africa and a product of valley erosion.

What type of erosion occurs in the upper course of a river?

What type of erosion is dominant in the upper course of a river? - Answers Hydraulic action takes place in the upper course of a river. This process of erosion is to do with the force of the water against the beds and banks.

What is the process of erosion and transportation in rivers?

The process of erosion and transportation goes on simultaneously in rivers comprising of the processes given below: Corrasion or abrasion – When river traction load is mechanically ground against the beds and banks of the river, it is called corrasion or abrasion.

How does erosion take place in nature?

Most erosion is performed by liquid water, wind, or ice (usually in the form of a glacier ). If the wind is dust y, or water or glacial ice is muddy, erosion is taking place.

Where does river erosion take place?

It is most common in the upper course of the river. The energy that is left after overcoming friction leads to the channel getting deeper. Lateral erosion erodes the banks of the river. This is more common in the middle and lower courses of a river.

What type of erosion occurs in the lower course?

The channel is wider and deeper as a result. C - in the lower course there is a lot less erosion, with only some lateral erosion. The channel is at its widest and deepest.

What is a river course of the river?

A river begins at a source (or more often several sources) which is usually a watershed, drains all the streams in its drainage basin, follows a path called a rivercourse (or just course) and ends at either at a mouth or mouths which could be a confluence, river delta, etc.

Why does erosion takes place in the upper course?

In its upper course, the river rushes down a steep slope and so flows swiftly, causing mainly erosion in this region.

What is upper course of a river?

Upper course river features include steep-sided V-shaped valleys, interlocking spurs, rapids, waterfalls and gorges. Middle course river features include wider, shallower valleys, meanders, and oxbow lakes. Lower course river features include wide flat-bottomed valleys, floodplains and deltas.

What happens in the middle course of a river?

In the middle course the river has more energy and a high volume of water. The gradient here is gentle and lateral (sideways) erosion has widened the river channel. The river channel has also deepened.

What's in the lower course of a river?

In the lower course, the river has a high volume and a large discharge. The river channel is now deep and wide and the landscape around it is flat. However, as a river reaches the end of its journey, energy levels are low and deposition takes place.

What is the lower course of river called?

DeltasLower course of a river Energy in the river is at its lowest and deposition occurs. . Deltas are often found at the mouth of large rivers. An example is the Nile Delta. Deltas are formed when a river deposits material faster than the sea can erode it.

What are the 3 river courses?

River Systems. The river has three different "courses", the Upper Course, Middle Course and Lower Course, each with their own different characteristics. waterfalls, interlocking spurs.

What is river erosion and its characteristics

To start this topic, we will first talk about the definition of river erosion and its characteristics . We can say that this type of erosion is the wear of the land surface produced by the water channeled into river waters , that is, the water of rivers and also in streams, torrents or other water currents.

Types of river erosion

Now that we know what river erosion is and what it consists of , we will delve further into the subject and we will tell you about the different types of river erosion that exist:

Consequences of river erosion

The reliefs formed by river erosion are one of the consequences of this process. However, we must mention that within river processes, river floods also occur, which are river overflows that cause excessive water content around the riverbeds.

Examples of river erosion

Finally, in this section we will briefly describe some examples of river erosion :

What is the process that wears away the river bed and banks?

Erosion is the process that wears away the river bed and banks. Erosion also breaks up the rocks that are carried by the river. There are four types of erosion : Hydraulic action - This is the sheer power of the water as it smashes against the river banks.

What happens when a river meets more resistant rock?

If the river meets more resistant rock it will flow around the rock. This produces interlocking spurs. The river erodes the valley bottom, but the valley sides are broken down by weathering.

How do rocks move?

The broken rock fragments (as a result of weathering) move down the slope through mass movements. These can be rapid, such as landslides or slow as with soil creep: 1 Landslides are occasional, rapid movements of a mass of earth or rock sliding along a steep slope. They can occur after periods of heavy rain, when the water saturates overlying rock, making it heavy and liable to slide. 2 Soil creep is a very slow movement, occurring on very gentle slopes because of the way soil particles repeatedly expand and contract in wet and dry periods. When wet, soil particles increase in size and weight, and expand at right angles. When the soil dries out, it contracts vertically. As a result, the soil slowly moves down slope.

What is a slow movement of a mass of earth or rock?

These can be rapid, such as landslides or slow as with soil creep: Landslides are occasional, rapid movements of a mass of earth or rock sliding along a steep slope. They can occur after periods of heavy rain, when the water saturates overlying rock, making it heavy and liable to slide.

The mechanism of humid erosion

Humid erosion involves the entire aspects of shaping the effects of running water from the activities of rainwater to that of the rivers.

The processes of river action

The river carries a lot of eroded material and forms the river’s load which can be categorised into three types –

River erosion and transportation

The process of erosion and transportation goes on simultaneously in rivers comprising of the processes given below:

What are the four types of erosion?

Rain, rivers, floods, lakes, and the ocean carry away bits of soil and sand and slowly wash away the sediment. Rainfall produces four types of soil erosion: splash erosion, sheet erosion, rill erosion, and gully erosion.

How does vegetation help with erosion?

Vegetation can slow the impact of erosion. Plant roots adhere to soil and rock particles, preventing their transport during rainfall or wind events. Trees, shrub s, and other plants can even limit the impact of mass wasting events such as landslides and other natural hazards such as hurricanes.

What is the process of changing the physical properties of rocks?

Physical erosion describes the process of rocks changing their physical properties without changing their basic chemical composition. Physical erosion often causes rocks to get smaller or smoother. Rocks erode d through physical erosion often form clastic sediments. Clastic sediment s are composed of fragments of older rocks that have been transported from their place of origin.

What is the force of ocean erosion?

The ocean is a huge force of erosion. Coastal erosion —the wearing away of rocks, earth, or sand on the beach—can change the shape of entire coastlines. During the process of coastal erosion, waves pound rocks into pebbles and pebbles into sand.

What is the term for the process in which earthen materials are worn away and transported by natural forces such as wind or

Encyclopedic Entry. Vocabulary. Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water. A similar process, weathering, breaks down or dissolve s rock, but does not involve movement.

How fast do ice sheets erode?

However, ice sheets do erode remarkably quickly—as much as half a centimeter (.2 inch) every year.

How does plant growth contribute to physical erosion?

Plant growth can also contribute to physical erosion in a process called bioerosion. Plants break up earthen materials as they take root, and can create cracks and crevice s in rocks they encounter. Ice and liquid water can also contribute to physical erosion as their movement forces rocks to crash together or crack apart. ...

Why does erosion occur?

As you can see, one of the main causes of erosion actually occurs because of materials that are being transported downstream. Any material that is broken away has to be transported and there are four ways in which this can happen:

Which erosion is most visible in the upper course?

We can usually see the most vertical erosion in the upper course. 2. Lateral Erosion. If you take a look at a cross profile diagram of a river, then it is easy to see that rivers widen at certain points.

What are the factors that play a role in erosion?

When we are talking about both vertical erosion and lateral erosion, there are four key factors that come into play: When we are talking about erosion, abrasion is one of the key factors that plays a prominent role. As rivers flow, they pick up material. This material can then scrape along the sides of the channel.

What does it mean when a valley has a cross profile?

If you are offered a cross profile diagram of a valley that appears to have sides that slope gently and quite a deep channel of water in the bottom, then that usually means that you are looking at the middle course of a river, where the gradient is medium. If you are offered a cross profile diagram of a valley that appears to be flat ...

What are the two types of erosion?

Erosion. Erosion shapes the landscape around rivers, but two types of erosion are actually occurring at the same time. Erosion. They are as follows: 1. Vertical Erosion. Vertical erosion is really easy to spot because we can see how deep the river valley is when we look at cross profile diagrams.

What is the path that a river follows?

When we refer to rivers that flow downhill, we call the path that they follow their course. Most rivers have upper, middle and lower courses. The former is closest to the source of the river and the latter is closest to the mouth of the river. Naturally, the course that a river follows affects the landscape that surrounds the river because ...

What is the role of hydraulic action in a river?

Before abrasion can take place, hydraulic action has an important role to play. The sheer force of the water in the river breaks rock particles away.

Answer

Vertical erosion is greatest in the upper course of a river. As the result of this typical features include steep valley sides, interlocking spurs, rapids, gorges and waterfalls. ... As the river or stream wears away the weak rocks, they travel across the surface of stronger rocks.

Answer

This is because soil erosion is the process of washing away of top layer of soil by the action of wind water etc....

What is the name of the type of erosion that occurs in the upper course of a river?

As a result, the source of the river retreats. This type of erosion of the river is called Headword Erosion. The sources of Sutlej and Koshi have retreated towards Tibetan side and of Kaveri towards west in western ghats. The other two important formations of the upper course of a river are—rapids and waterfalls.

Which river valley takes the shape of I instead of V?

The river valley takes the shape of I instead of V. The Grand Canyon of the river Colorado of U.S.A. is one of the best examples. On the other hand, when river flows through soft rocks in the heavy rainfall areas erosion takes place towards the head of the river in addition to vertical and lateral erosion.

What is the meandering channel of the Dhansiri River?

The additional sediments carried by the river during the floods are deposited in this part. The channel is sometimes blocked, the river changes its course very often and becomes winding. Such a winding channel is known as a meander. The lower part of the Dhansiri River of Assam has a highly meandering course.

What are the main activities of a river in the upper course?

Erosion and transportation are the main activities of a river in the upper course. A river has a deep and narrow channel in this stage. Moreover, some of the rocks over which a river flows are very hard, while the others are soft. As a result of this, the river course is not smooth.

Where are oxbow lakes?

There are many ox-bow lakes on the two sides of Beki and Dhansiri rivers of Assam. At the time of flood, water inundates the low-lying area by the side of the river. The silt carried by the flood is thus deposited in this area year after year and a plain is built up. Such a plain is known as flood plain.

What is the last part of a river near its mouth called?

The last part of a river near its mouth is called the lower course. In this part the slope of the river bed is not very steep. The current is also very slow. Deposition is the main activity of a river at this stage.

What is the name of the plain at the foot of the mountain?

It is called Alluvial Fan. In course of time many alluvial fans join together to make a plain. This type of plain at the foot of the mountain is called Bhabar. 3.