Chapter 11-rivers

Question 1

Stages of a river

Answer 1

Upper/young

Mature/middle

Lower/old

Question 2

Features of a upper river

Answer 2

1. Steep fast flowing
2. Little water
3. Lots of erosion
4. Narrow, shallow channel

Question 3

Features of the middle of the river

Answer 3

1. River starts to slow down
2. More water
3. Still eroding
4. Wider,deeper channel

Question 4

Stages of a lower river

Answer 4

Slow moving river

Much more water

Depositing not eroding

Very wide, very deep channel

Question 5

Ways of river transportation

Answer 5

Rolling,bouncing,suspension,solution

Question 6

Explain a way of river transportation- rolling/traction

Answer 6

The larger stones are rolled along the bed of the river. This process is known as traction

Question 7

Explain the transportation process of bouncing/ saltation

Answer 7

The smaller pebbles are bounced along the bed of the river.

Question 8

Explain the process of transportation called suspension

Answer 8

Light materials such as sand and silt float along in the river

Question 9

Explain the process of transportation called solution

Answer 9

Materials dissolve in the water and are carried along by the river

Question 10

Name the ways of river erosion

Answer 10

Hydraulic action, abrasion,attrition, solution

Question 11

Name some youthful stage features

Answer 11

Waterfall,v- shaped valleys . Interlocking spurs

Question 12

Explain hydraulic action

Answer 12

The force of the moving water wears away the banks and the bed of the river

Question 13

Explain abrasion

Answer 13

Small stones carried by the river wear away the banks and bed of the river

Question 14

Explain attrition

Answer 14

The small stones in the river are worn down and broken up as they hit off each other

Question 15

Explain solution

Answer 15

Rocks such as limestone and soil are dissolved by acids in the water

Question 16

Explain the feature of a waterfall

Answer 16

A waterfall is a rewrite of river erosion in the youthful stage of a river

A waterfall is a point where the is a interruption in the river profil and the water makes a vertical drop

Question 17

Name a example of a waterfall

Answer 17

Tork waterfalls, Killarney, co.kerry

Question 18

Explain waterfalls

Answer 18

Waterfalls develop when a layer of hard rock lies on top of a layer of soft rock. The soft rock is eroded by abrasion and by hydraulic action. The hard rock is overcut creating a overhang. The water falls into softer rock below forming a plunge pool a soft rock continues to be eroded at much faster rate than the hard rock. The hard rock is no longer supported and the overhand collapses

Question 19

What is a v-shaped valley

Answer 19

It is a valley that is a steep sided valley in the shape of a v

Question 20

What are interlocking spurs

Answer 20

They are the areas of high ground that jut out at both sides of a v-shaped valley

Question 21

Name a mature stage freature

Answer 21

Meanders

Question 22

Explained a meanders feature

Answer 22

Meanders are curves or bends that develop along the mature course of a river

Question 23

Name a example of a meander

Answer 23

The river Shannon and the river moy

Question 24

Explain meanders

Answer 24

As the water grows around a slight bend,the water at he outer or concave bank is deeper and flows more quickly as a result it has more power to erode the bank through hydraulic action and a river cliff forms

The water at the inner/convex bank is shallower and flows more slowly. As a result deposition occurs creating a pant bar

Erosion and deposition continue overtime and the meander becomes mor prominent

Question 25

What is a oxbow lake

Answer 25

An oxbow lake is a horseshoe shaped lake that was formed when a meander was cut off from the river

Question 26

Case study: anchacrusha power station, Shannon

Answer 26

Th power station was built in the 1920s by the Irish government

It was built by a German company,Siemens,and cost 5 million

Question 27

How was the power station built

Answer 27

At first people thought that the land at river Shannon flowed through was to flat to harness hydroelectric power. To over come this wier was built to split the course of the river Shannon in two one section was a continuation of the natural course of the river. The other section was raised up called a headrace canal and directed water straight to the power station. The pressure of the flowing water is used to turn turbines and generate electricity

Question 28

What is a source

Answer 28

It is the beginning or start of a river

Question 29

What is a course

Answer 29

It is the route the river is going

Question 30

What is the confluence

Answer 30

It is the point where two rivers join together

Question 31

What is a tributary

Answer 31

A stream or smaller river that flows into a larger stream or river

Question 32

What is the mouth of a river

Answer 32

The point where a river comes to a end

Question 33

What is the drainage basin

Answer 33

Th area of land drained by a river

Question 34

What is the watershed

Answer 34

The edge of highland surrounding a drainage basin

Question 35

What is the estuary

Answer 35

The part of a river mouth that is tidal

Question 36

What are features of the old stage

Answer 36

Levees,floodplains,deltas

Question 37

Explain a feature of deposition with example

Answer 37

Levees are raised banks of alluvium along the bank of some rivers in their old age. Levees can naturally occur but can also be man made

Leaves form because of flooding. During normal flow the river is confined in its channel and deposition will occur on the river bed. However during flood events the river overflow it’s channel and pours over the floodplain. When a river floods and spreads out over the floodplain it looses its energy and begins to deposit load. The heavier material is deposited close to the banks while lighter materials is carried further across the floodplain. After many periods of flooding these deposits build up to form levees

River Shannon and river may

Question 38

Explain alluvium

Answer 38

Clay,silt,sand

Question 39

Advantages of the powerstation

Answer 39

The power station at and crusher allows the generation of hydroelectric power – a clean, renewable source of energy. When the power station was built it provided Ireland with 96% of its total energy. Between 1822–1930 The number of people employed in industry grew by 30,000. The production of cheap reliable electricity meant that Irish industry could grow. The dam built at ardchrusha and the Weir control the flow of water and limit the risk of flooding along the river Shannon

Question 40

Disadvantages of the powerstation

Answer 40

The dam acts as a well across the river Shannon. Water builds up behind it creating a reservoir. The reservoir flooded the farmland leading to a loss of fertile, productive farmland. Some families had to re-locate and move on because of flooding caused by the river Reservoir.