What is Cross river profile?
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What is Cross river profile?
A cross profile shows a cross-section of a river’s channel and valley at a certain point along the river’s course. A – as the river flows downhill there is an increase in vertical erosion . The channel is shallow and narrow because there is not a lot of water in the channel.
What is cross-section of river?
What is a cross-profile? River cross profiles show you a cross-section, taken sideways, of a river’s channel and/or valley at certain points in the river’s course. A channel cross-profile only includes the river whereas a valley cross-profile includes the channel, the valley floor and the sides of the valley.
What does the cross sectional area of a river show?
Channel Velocity This is only the average velocity however; a cross-section of a river shows that the velocity varies from one side to the other. The lowest velocities are found where the river is shallow and so friction is greatest. The maximum velocity is found near the river’s surface where the channel is deep.
Why does the cross sectional area of a river increase downstream?
As the river flows downstream it is joined by tributaries, increasing the volume of water, velocity and therefore its erosive power. This enables it to cut a deeper channel as it flows downstream. Downstream, the channel becomes wider as the gradient becomes more gentle leading to less vertical erosion.
What is the difference between upper middle and lower 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.
How does the profile of a river change downstream?
As the river moves from the source to the mouth – both the depth of the river and the width of the river will both increase. The load of a river will also change as it is transported and eroded along the river’s profile. As a result, the size and shape of stones will change as they journey through the river profile.
Why is the lower course of a river wider?
In the lower course there is an absence of large rocks and the river channel, being wider and deeper applies less friction to the flow. It is this absence of friction, which creates the smooth channel that allows the velocity of rivers to increase despite the more shallow gradient of the channel.
How do you draw a cross profile in geography?
- How to Draw a Cross-Section of a Map.
- Take a thin strip of paper and place it along the transect line on the map.
- On a piece of graph paper, draw the horizontal axis of your graph exactly the same length as the transect A-B.
- Draw two vertical axes using a suitable scale.
What is the bottom of a river called?
A stream bed or streambed is the channel bottom of a stream or river, the physical confine of the normal water flow. The lateral confines or channel margins are known as the stream banks or river banks, during all but flood stage.
What is lower river course?
The lower course of the river is where the it comes to meet the sea at the mouth, and starts at the relatively straightening path preceeding it, surrounded by flat land. Features of the Lower Course of Rivers: High Volume and Discharge – At the lower course of a river, the river is at its biggest volume capacity.
What are the features of 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 cross section profile?
A graphic representation of the sections that are in a linear work, on cutting the axis of the aforementioned work with vertical planes perpendicular to it and defining the trace in elevation.
How does a river change in the lower course?
It often flows over a series of waterfalls and rapids. As a river flows down steep slopes, the water performs vertical erosion . This form of erosion cuts down towards the river bed and carves out steep-sided V-shaped valleys. As the river flows towards the mouth, the gradient of the slope becomes less steep.
How does a river change from upper to lower course?
When discharge is high vertical erosion erodes the river bed and larger sediments are transported by traction. Mid-course – here the gradient becomes less steep. The river channel gets deeper and wider as the bed and banks are eroded. The sediment load of the river gets smaller in size.
What are the characteristics of the lower course?
What is the lower course of a river called?
Lower 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.
