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River Deposiition
Deposition
Question | Answer |
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Name the 2 types of river erosion and state how they are formed. | Lateral and Vertical Erosion. Lateral Erosion widens the banks of the river, while Vertical Erosion deepens the riverbed. |
What is Cavitation? | These are shock-waves caused by air bubbles bursting, which loosen pieces of mud and stone. |
How and why does Hydraulic Action occur? | Hydraulic Action occurs when river flows rapidly downstream, hitting off the beds and banks of the river. The sheer force of turbulent water. |
Name the processes that contribute to River Erosion. | Hydraulic Action, Abrasion, Attrition and Solution. |
Name a land-form created in the upper course of the river and describe how it was formed. | Waterfall. These occur due to faulting, when a section of rock is uplifted the rest, causing the river to flow over the edge. |
Name and Explain one feature formed in the middle/mature stage of the river. | Oxbow Lake is a horseshoe shaped lake that has been cut off from a river. Examples can be found in the river's old stage. Eg; Shannon River. |
Name a waterfall you have studied and describe how Waterfalls occur. | Torc Waterfall. Waterfalls occur due to hydraulic action, abrasion. The process of abrasion increases the rate of erosion as broken rock becomes trapped in these hallows causing them to deepen and widden. |
Humans interact with rivers regularly. Describe 1 positive and 1 negative affect humans have on rivers. | Positive: The building of canals on the River Shannon, has made the Shannon more accessible for tourism and recreation. Lough Derg has become a popular tourist attraction for water sports, fishing and senior tours. Negative; Fish stocks eg Salmon and Eel |
When does Deposition occur in the river's course? | Deposition occurs when a river loses its energy, or is unable to carry its load any longer. |
Name the 3 reasons why deposition occurs. | Reduced Velocity, Reduced Discharge and Increased Load. |
Explain one of these in detail. | Reduced Velocity occurs when a river loses its energy. This normally occurs at the mature and old stage, as the landscape slope is reduced. Human Interference also causes reduced speed due to dam construction. |
How does Increased Load happen? | An increase amount of sediment can occur during heavy rainfall. during heavy rainfall, more soil erosion occurs, washing it into the rivers, increasing its load. River eventually transports its load. |
Which one of these occurs in the middle course of the river? Meanders, V-shaped Valley or Oxbow Lake. | Meanders occur in the midddle course of the |