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Year 11 GCSE Geography (Edexcel) REVISION

Changing UK Landscapes – Part 2

1. River Processes

2. Glossary of key words

3. Revision Quiz (to complete and hand in within 1 week)

4. River Landforms



7. Human Activities on Rivers



10. UK Landscapes



River processes

Erosion, transportation and deposition all occur in a river. Moving from the upper course to the lower course, the rates of erosion, transportation and deposition change.

Erosion

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. Air becomes trapped in the cracks in the rock of the river bank and bed, and causes the rock to break apart.

· Abrasion - When pebbles grind along the river bank and bed in a sand-papering effect.

· Attrition - When rocks that the river is carrying knock against each other. They break apart to become smaller and more rounded.

· Solution - When the water dissolves certain types of rocks, eg limestone.

Weathering and mass movement

As the river flows, it erodes the land creating a valley with steep sides called a v-shaped valley. 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.

There are three types of weathering:

· Mechanical – physical changes causes rocks to break down, for example, a change in temperature from day to night causes rock to expand and contract and break up (eg onion skin weathering). Or, changes in temperature cause water to freeze and expand, melt and contract leading to freeze-thaw weathering.

· Chemical – rainwater is slightly acidic and over time this wears away the rock.

· Biological - occurs when plants and animals wear away rocks, for example, roots growing in cracks in the rock or animals such as rabbits burrowing into rock.

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:

· 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.

· 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.

Transportation

The river picks up sediment and carries it downstream in different ways. There are four types of transportation:

· Traction - large, heavy pebbles are rolled along the river bed. This is most common near the source of a river, as here the load is larger.

· Saltation - pebbles are bounced along the river bed, most commonly near the source.

· Suspension - lighter sediment is suspended (carried) within the water, most commonly near the mouth of the river.

· Solution - the transport of dissolved chemicals. This varies along the river depending on the presence of soluble rocks.

Deposition

When the river loses energy, it drops any of the material it has been carrying. This is known as deposition. Factors leading to deposition:

· shallow water

· at the end of the river's journey, at the river's mouth

· when the volume of the water decreases

Drainage basins

A river's water can fluctuate over time. Understanding the hydrological cycle is useful in order to understand how and why the amount of water fluctuates. A drainage basin is the area of land around the river that is drained by the river and its tributaries.

· Watershed - the area of high land forming the edge of a river basin.

· Source - where a river begins.

· Mouth - where a river meets the sea.

· Confluence - the point at which two rivers meet.

· Tributary - a small river or stream that joins a larger river.

· Channel - this is where the river flows.

River profiles

Long profile

A long profile is a line representing the river from its source (where it starts) to its mouth (where it meets the sea). A river changes with increasing distance downstream from its source towards its mouth. It moves through its upper course, to its mid-course and finally into its lower course.

Steep valley sides are typical of a river's upper course in upland areas. The valley here has steep sides and the valley bottom is narrow. This is why valleys like this are called V-shaped valleys.

· Upper course - this is where the river starts and is usually an upland area. Slopes are steep - this can increase the velocity of the river after heavy rainfall, when discharge is high. The river channel is narrow and shallow here. The river's load is large in the upper course, as it hasn't been broken down by erosion yet. 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. Small meanders and a small floodplain can be found in this part of the river.

· Lower course - the final course of the river is where the land is a lot flatter. The river's load is fine sediment, as erosion has broken down the rocks. The river channel is at its widest and deepest as it flows towards its mouth. Deposition is the main process in this part of the river, which creates large floodplains and deltas.

The Bradshaw Model shows the changes that occur as a river flows from its source to its mouth.

Cross profile

A cross profile is a cross section of a river's valley and channel.

· 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.

· B – as the river flows into the middle course, there is some vertical erosion but more lateral erosion. 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.

Glossary

· cross profile

A cross-section of the valley and channel of a river.

· deltas

A river landform made of deposited sediment at the mouth of as river.

· discharge

The volume of water in a river passing a point in a given time. Measured in cumecs (cubic metres per second).

· floodplain

An area of low-lying land next to a river which is prone to flooding.

· freeze-thaw weathering

When water in rocks freezes and expands, breaking the rock apart.

· interlocking spur

Hill that a river meanders around in a V-shaped valley. When viewed from downstream, these spurs appear to be locked together.

· landslide

When the rocks on the side of a steep slope give way.

· lateral erosion

The wearing away of the landscape when a river erodes sideways.

· load

The particles of rock carried by a river.

· long profile

A section of the course of a river drawn from source to mouth.

· lower course

The final section of a river located on flat land.

· mass movement

A large-scale downward movement of rocks and material.

· meander

A bend in a river.

· middle course

The middle section of a river which has sloping land.

· mouth

The place where a river meets the sea.

· river channel

The part of the river that holds the water.

· source

The place where a river starts in its upper course.

· transportation

To move objects or people from one place to another.

· tributary

A small river that joins the main river channel.

· upper course

The highest section of a river located in the mountains.

· valley

A low area of land between hills or mountains, typically with a river flowing through it

· velocity

The speed of an object in a particular direction.

· vertical erosion

When the land is eroded or worn away in a downwards direction, eg a river that is high up will erode vertically because gravity pulls the water downwards.

· weathering

The breaking down of rocks in situ by the action of weather, plants, animals and chemical processes.

River landforms

Erosional landforms include interlocking spurs, waterfalls and gorges. Meanders and oxbow lakes use erosional and depositional processes in their creation. Examples can be found along the River Tees.

Erosional landforms

The process of erosion can create different landforms. The erosional features are often found in the upper course of the river.

Waterfall and gorges

A waterfall is a sudden drop along the river course. It forms when there are horizontal bands of resistant rock (hard rock) positioned over exposed, less resistant rock (soft rock).

1. The soft rock is eroded quicker than the hard rock and this creates a step.

2. As erosion continues, the hard rock is undercut forming an overhang.

3. Abrasion and hydraulic action erode to create a plunge pool.

4. Over time this gets bigger, increasing the size of the overhang until the hard rock is no longer supported and it collapses.

5. This process continues and the waterfall retreats upstream.

6. A steep-sided valley is left where the waterfall once was. This is called a gorge.

Interlocking spurs

In the upper course there is more vertical erosion. The river cuts down into the valley. If there are areas of hard rock which are harder to erode, the river will bend around it. This creates interlocking spurs of land which link together like the teeth of a zip.

Erosional and depositional landforms

Meanders

As the river makes its way to the middle course, it gains more water and therefore more energy. Lateral erosion starts to widen the river. When the river flows over flatter land they develop large bends called meanders.

· As a river goes around a bend, most of the water is pushed towards the outside. This causes increased speed and therefore increased erosion (through hydraulic action and abrasion).

· The lateral erosion on the outside bend causes undercutting of the bank to form a river cliff.

· Water on the inner bend is slower, causing the water to slow down and deposit the eroded material, creating a gentle slope.

· The build-up of deposited sediment is known as a slip-off slope (or sometimes river beach).

Oxbow lakes

Due to erosion on the outside of a bend and deposition on the inside, the shape of a meander will change over a period of time. Erosion narrows the neck of the land within the meander and as the process continues, the meanders move closer together. When there is a very high discharge (usually during a flood), the river cuts across the neck, taking a new, straighter and shorter route. Deposition will occur to cut off the original meander, leaving a horseshoe-shaped oxbow lake.

Depositional landforms

Floodplains

A floodplain is an area of land which is covered in water when the river bursts its banks.

They form due to both erosion and deposition. Erosion removes any interlocking spurs, creating a wide, flat area on either side of the river. During a flood, material being carried by the river is deposited (as the river loses its speed and energy to transport material). Over time, the height of the floodplain increases as material is deposited on either side of the river.

Floodplains are often agricultural land, as the area is very fertile because it's made up of alluvium (deposited silt from a river flood). The floodplain is often a wide, flat area caused by meanders shifting along the valley.

Levees

· Levees occur in the lower course of a river when there is an increase in the volume of water flowing downstream and flooding occurs.

· Sediment that has been eroded further upstream is transported downstream.

· When the river floods, the sediment spreads out across the floodplain.

· When a flood occurs, the river loses energy. The largest material is deposited first on the sides of the river banks and smaller material further away.

· After many floods, the sediment builds up to increase the height of the river banks, meaning that the channel can carry more water (a greater discharge) and flooding is less likely to occur in the future.

Estuaries

An estuary is where the river meets the sea. The river here is tidal and when the sea retreats the volume of the water in the estuary is less reduced. When there is less water, the river deposits silt to form mudflats which are an important habitat for wildlife.

An estuary and its mudflats

Deltas

Deltas are found at the mouth of a river, as it enters a sea or lake. The sediments the river has been transporting by bedload and suspended load are deposited as velocity decreases as the river flows into the sea. Deltas are usually made up of three types of deposit:

· The larger and heavier sediments are the first to be deposited as the river loses its energy. These form the topset beds.

· Medium-sized sediments travel little further before they are deposited, forming the foreset beds.

· The finest sediments travel furthest into the lake before deposition and form the bottomset beds.

Clarence River delta from the sea, South Island, New Zealand

Case study: river landforms - River Tees

The River Tees is located in the north of England. The source of the River Tees is located in the Pennines and it flows east to its mouth where the river joins the North Sea.

Upper course

· The upper course has hard impermeable rocks. Here, vertical erosion has formed a V-shaped valley.

· High Force, the UK's largest waterfall at 21 metres high, is located in the upper course. An area of hard rock, called Whin Sill (or Whinstone), is located above a layer of soft rocks (sandstone and shale) and together they create this impressive waterfall.

High Force waterfall

Middle course

· As the River Tees starts to erode sideways (lateral erosion), it forms meanders. These can be identified in the middle course near Barnard Castle.

© Crown copyright and database rights 2015 Ordnance Survey

Lower course

· Near Yarm, the meanders in the lower course are much larger, and oxbow lakes have formed. In this area there are also levees which have formed when the river has flooded.

· The River Tees has a very large estuary with mudflats and sandbanks which supports wildlife in the area. Sites such as Seal Sands are protected areas.

The River Tees estuary and its mudflats

Glossary

1. abrasion

When rocks carried by the sea water wear away the landscape, eg cliff face/headland.

2. alluvium

The sediment deposited by rivers. Also known as silt.

3. bed load

(Also written as bedload.) The sediment carried by a river by being bounced or rolled along its bed.

4. deposition

When material is deposited or left behind, eg when a river loses its energy and is unable to carry its load any further.

5. discharge


6. erosion

The wearing away of pieces of rock, soil or other solid materials.

7. estuary

The open mouth of the river where it meets the sea.

8. floodplain

An area of low-lying land next to a river which is prone to flooding.

9. gorge

A deep, narrow passage that usually has a river running through it.

10. hydraulic action

Erosion caused by the force of river water hitting cracks in the side of the river bank. The air in the cracks becomes compressed and then explodes outwards, breaking off bits of rock.

11. interlocking spur

Hill that a river meanders around in a V-shaped valley. When viewed from downstream, these spurs appear to be locked together.

12. lateral erosion

The wearing away of the landscape when a river erodes sideways.

13. levee

Ridges or banks formed by deposits of alluvium left behind by the periodic flooding of rivers. Can also be artificially constructed banks or walls.

14. lower course

The final section of a river located on flat land.

15. meander

A bend in a river.

16. middle course

The middle section of a river which has sloping land.

17. mudflat

Sheltered coastal areas where mud is deposited by tides or rivers.

18. Oxbow lakes

a curved lake formed from a horseshoe bend in a river where the main stream has cut across the narrow end and no longer flows around the loop of the bend.

19. plunge pool

The pool of water found at the bottom of a waterfall. It is an erosional feature which has been created by a combination of hydraulic action and the abrasion of the plunging water.

20. river cliff

Steep bank created on the outside of a river bend by the erosive effect of fast-flowing water undercutting the bank.

21. slip-off slope

Gently sloping bank found on the inside of a river bend because of slow-flowing water, depositing sediment.

22. source

The place where a river starts in its upper course.

23. suspended load

Very small and light sediment, usually fine clay and silt, transported by the river.

24. upper course

The highest section of a river located in the mountains.

25. velocity

The speed of an object in a particular direction.

26. vertical erosion

When the land is eroded or worn away in a downwards direction, eg a river that is high up will erode vertically because gravity pulls the water downwards.

27. waterfall

A steep drop in a river.

Human activities on rivers

Hard engineering management involves using artificial structures, such as dams and embankments. Soft engineering management is a more natural approach to manage flooding, such as floodplain zoning.

Flood risk

Flooding occurs when a river bursts its banks and overflows onto the surrounding land. There are many factors which can cause a flood - often the natural landscape can influence flooding and also human interactions can increase the risk.

Causes of flooding

· Prolonged rainfall - if it rains for a long time, the land around a river can become saturated (it's holding as much water or moisture as can be absorbed). If there is more rainfall it cannot be soaked up, so it runs along the surface. This is known as surface run-off.

· Heavy rainfall - if there is heavy rainfall there is less chance of it being soaked up by the soil (infiltration) so it runs off into the river. The faster the water reaches the river, the more likely it will flood.

· Relief - a steep valley is more likely to flood than a flatter valley because the rainfall will run off into the river more quickly.

· Geology - permeable rocks allow water to pass through pores and cracks, whereas impermeable rocks do not. If a valley is made up of impermeable rocks, there is a higher chance of flooding as there is an increase in surface run-off.

· Vegetation - trees and plants absorb water, this is known as interception. Lots of vegetation reduces flood risk. Sometimes people cut down trees (deforestation). This will increase the flood risk, as the water will not be intercepted and flow into the river.

· Urban land use - when an area surrounding a river is built on, there is an increase in the amount of tarmac and concrete, which are impermeable surfaces. Drains and sewers take water directly to the river which increases flood risk.

Hydrographs

A hydrograph shows how a river responds to a period of rainfall.

· Peak discharge - maximum amount of water held in the channel.

· Peak rainfall – maximum amount of rainfall (millimetres).

· Lag time - the time taken between peak rainfall and peak discharge.

· Rising limb - shows the increase in discharge on a hydrograph.

· Falling limb - shows the return of discharge to normal/base flow on a hydrograph.

· Base flow - the normal discharge of the river.

The lag time can be short or long depending on different factors:

· Geology discharge - if the rocks under the ground are impermeable and water cannot drain through the rock layer resulting in rapid overland flow and a shorter lag time. Permeable rocks encourage a slow transfer by groundwater flow, hence a longer lag time.

· Soil type – clay soils do not drain easily and become saturated very quickly. This results in rapid overland flow and shorter lag times. Dry soils slow down water transfer leading to longer lag times.

· Slope - steep slopes lead to rapid water transfer and shorter lag times. Gentle slopes slow down water transfer making the lag time longer.

· Drainage basin shape - a high density basin has more streams and rivers which speed up water transfer and shorten lag time. A low density basin has less streams and rivers leading to a slower transfer and longer lag time.

· Antecedent conditions - wet conditions before a storm cause the ground to become saturated. This speeds up overland flow and shortens lag time. Drier conditions mean the rainfall can infiltrate into the soil slowing down lag time.

· Vegetation - if there is no vegetation in an area, the water runs off into the river quicker, therefore it would have a short lag time. Alternatively, if there is plenty of vegetation in the area, the lag time would be longer as the plants would intercept the rainfall.

Hard engineering

Flooding can cause damage to homes, businesses, infrastructure and communications.

Hard engineering involves building artificial structures which try to control rivers. They tend to be more expensive. Each hard engineering strategy has its advantages and disadvantages.

Dams and reservoirs

A man-made reservoir

The dam traps water, which builds up behind it, forming a reservoir. Water can be released in a controlled way.

Advantages

· Can be used to produce electricity by passing the water through a turbine within the dam.

· Reservoirs can attract tourists.

Disadvantages

· Very expensive.

· Dams trap sediment which means the reservoir can hold less water.

· Habitats are flooded often leading to rotting vegetation. This releases methane which is a greenhouse gas.

· Settlements are lost leading to the displacement of people. In developing countries locals are not always consulted and can have little say in where they are relocated.

River straightening and dredging

A river dredger in the Netherlands

Straightening the river speeds up the water so high volumes of water can pass through an area quickly. Dredging makes the river deeper so it can hold more water.

Advantages

· More water can be held in the channel.

· It can be used to reduce flood risk in built-up areas.

Disadvantages

· Dredging needs to be done frequently.

· Speeding up the river increases flood risk downstream.

Embankments

The Moskva River embankment, Moscow

Raising the banks of a river means that it can hold more water.

Advantages

· Cheap with a one-off cost

· Allow for flood water to be contained within the river.

Disadvantages

· Look unnatural.

· Water speeds up and can increase flood risk downstream.

Flood relief channels

The Morganza spillway on the Mississippi river is a flood relief channel

The floodwater flows into the relief channel and is taken either to an area where it can be absorbed, or re-enters the river further down its course.

Advantages

· Removes excess water from the river channel to reduce flooding.

Disadvantages

· Expensive to build.

· If water levels continue to rise, the relief channel may also flood.

Soft engineering

Soft engineering does not involve building artificial structures, but takes a more sustainable and natural approach to managing the potential for river flooding. Each approach has its advantages and disadvantages.

Flood warnings and preparation

The environmental agency monitors rivers and issues warnings via newspapers, TV, radio and the internet when they are likely to flood so people can prepare.

Advantages

· People have time to try to protect their properties, eg with sandbags.

· Many possessions can be saved, resulting in fewer insurance claims.

Disadvantages

· Some people may not be able to access the warnings.

· Flash floods may happen too quickly for a warning to be effective.

· They do not stop land from flooding - they just warn people that a flood is likely.

Floodplain zoning

Allowing only certain land uses on the floodplain reduces the risk of flooding to houses and more important buildings.

Advantages

· More expensive buildings and land uses are further away from the river, so have a reduced flood risk.

· Less damage is caused, leading to fewer insurance claims.

Disadvantages

· Not always possible to change existing land uses.

· Planners have to decide what type of flood to plan for.

Case study: the Cumbrian floods 2015

In December 2015, Storm Desmond set a new record, with 341.4 millimetres of rain falling over a 24-hour period. This led to flooding in Cumbria. One town particularly affected was Cockermouth, despite the construction of a self-closing flood barrier in the town in 2013 as a response to flooding in previous years.

Physical causes

The warm air from the mid-Atlantic caused relief rainfall over the Cumbrian Mountains. The warmer the air, the more moisture it holds.

1. Warm air from the mid-Atlantic moved towards land due to the prevailing wind.

2. The warm air was forced upwards by the Cumbrian Mountains.

3. As the air cooled, it condensed to form heavy rain. The weather front stopped over Cumbria.

4. The falling rain poured into the River Derwent and River Cocker.

5. The two rivers confluence at Cockermouth, which led to significant flooding.

Impacts

Social

· Over 43,000 homes across Cumbria and Lancashire suffered from power cuts.

· Approximately 5,200 homes were affected by flooding.

· One person died in Cumbria.

· About 40 schools closed in Cumbria.

Economic

· Rail and road services were disrupted.

· Many businesses suffered through damage to property and stock.

· The estimated cost was £500 million across Cumbria. The government provided £50 million for flood victims and businesses.

· Insurance companies have been predicted to pay out up to £325 million to residents and businesses.

Environmental

· Rivers were significantly altered with increased rates of erosion.

· Heavy rain washed nutrients from soil.

· Vegetation was flooded, causing habitat loss.

The River Derwent burst its banks in 2009 and again in 2015, leading to extensive flooding of homes and businesses in Cockermouth

Reducing the risks

Following the earlier 2009 floods in Cockermouth, a flood prevention scheme was implemented. River dredging was used to increase the capacity of the river channel so it could hold more water in the future. A self-closing flood barrier was also installed in 2013 to increase the height of the river banks. However, the record breaking rainfall of December 2015 was too much for the barrier to contain. Flooding is becoming more frequent in the UK. The Environmental Agency is responsible for monitoring the potential for flooding. They evaluate the risk of flooding and issue warnings for areas. They use three codes to help people be able to prepare:

Alerting people to the risk of potential flooding can give the public the chance to evacuate the area, reducing injuries and deaths. Economic losses can also be reduced as people and businesses can move their valuables to a safer area. The government has pledged to spend £2.3 billion on flood defences between 2016 and 2022.

Glossary

1. confluence

The meeting point where one river joins onto another river.

2. deforestation

The cutting down of trees and forests to allow a different land use.

3. discharge


4. greenhouse gas

The gases responsible for global warming - carbon dioxide, methane, nitrous oxide and CFCs (chlorofluorocarbons).

5. groundwater

Where water is stored in rocks beneath the ground.

6. hard engineering

The use of man-made structures to control the coast.

7. hydrograph

A graph to show how a river responds to a period of rainfall.

8. impermeable rock

Rock which does not allow water to pass through it, eg granite.

9. infiltration

Water that soaks into the ground.

10. interception

When trees and plants stop water from reaching the surface.

11. permeable rock

A type of rock which allows water to pass through its joints and cracks, eg limestone.

12. relief rainfall

Rain that occurs on high land and mountainous areas.

13. saturated

Unable to contain any more liquid.

14. soft engineering

The use of natural, sustainable solutions to control the coast.

15. surface run-off

The water that runs over the surface of the land when the soil is unable to absorb it.

16. sustainable

An activity which does not consume or destroy resources or the environment.

UK landscapes

The physical landscape of the UK is varied and includes upland and lowland areas. The landscape has been shaped by glaciation, rivers and rock types.

The UK's main rock types

Rocks can be classified in to three main groups - igneous, sedimentary and metamorphic. These three different rock types can be found in distinct areas of the UK.

Igneous rocks - these rocks are a result of volcanic activity in the past, when Britain was close to a plate boundary. Some of the igneous rocks are due to lava erupting at constructive plate boundaries. When the lava reached the surface, it cooled and solidified to form basalt rock. An example of this is the Giant's Causeway in Northern Ireland.

Other rocks are formed by hot molten magma beneath the Earth's surface cooling and solidifying as an intrusive rock under the ground, such as granite. This is later exposed as the rocks above are weathered and eroded at the Earth’s surface.

Igneous rock

Igneous basalt rocks at Giant's Causeway in Northern Ireland

Granite rock

Granite rock at Hound Tor, Dartmoor

Limestone

Limestone is one type of sedimentary rock, as seen in the Yorkshire Dales

Sandstone

Sandstone cliffs at Bridport, Dorset

Slate

Slate sea stacks in Devon. Slate is an example of metamorphic rock.

Sedimentary rocks – these are made up of small particles of sand and rock, which have been transported by the wind, rivers and ice and are usually deposited on lake or seabed. Over many millions of years, successive layers of sediments accumulate. These layers of sediments are compressed by the weight of the deposits above, into sedimentary rocks. These rocks form in layers, known as bedding planes.

When sand is compressed it forms sandstone. When mud is compressed it becomes clay. Limestone and chalk come from the remains of dead plant, animal and marine species and are rich in calcium carbonate and contain fossils. Many of these rocks were formed over 300 million years ago, in warm tropical seas during the carboniferous period. The existence of these rocks is evidence that Britain was at a different latitude compared to today. This suggests movement of continental areas of the globe, which is explained by the modern theory of plate tectonics.

Metamorphic rocks - these are rocks that have been changed in shape and form by intense heat and pressure at a plate boundary or along a fault line. These rocks start as either igneous or sedimentary rocks and are crystallised under the intense heat and pressure conditions to form rocks such as slates, schists, and marble. These rocks are very hard in nature and are often used as roof material.

Distribution of the UK's rock types

The various rock types are distributed across the British Isles.

· Igneous rocks can be found mainly in upland areas in Scotland, in the Lake District in North West England and Snowdonia in North Wales and Northern Ireland.

· Metamorphic rocks are found in Northern Ireland and Scotland.

· Sedimentary rocks can be found across lowland areas of southern and central parts of England.

Physical landscapes in the UK

The UK has a varied landscape as the relief of the land changes in different parts of the country.

Relief

Relief refers to the way the landscape changes in height. Upland areas are high above sea level. They are often, but not always, mountainous. Lowland areas are not very high above sea level. They are often flat. The shape of the landscape is largely determined by:

· glaciation

· rivers

Upland areas are mainly found in:

· Scotland - The Northwest Highlands, the Cairngorm Mountains, the Grampian Mountains and the Southern Uplands. Ben Nevis is the UK's highest peak and is found in the Grampian Mountains.

· England - The Pennines, Lake District, Dartmoor and Exmoor. Scafell Pike is the highest mountain in England and is found in the Lake District.

· Wales - Snowdonia and the Brecon Beacons. Snowdon is the highest mountain in Wales and is found in Snowdonia.

Lowland areas can be found in the following places:

· around The Wash (East Anglia and Lincolnshire)

· Lincolnshire

· the Fens in East Anglia - the lowest place in the UK

· the Midlands

· the London Basin

· the Vale of York

The role of glaciers in shaping the land

During the last ice age, ice covered a large part of the UK. This ice eroded the land producing some of the mountainous landscapes which exist today.

Major rivers in the UK

The erosive power of rivers has shaped the relief of the land.

The major river systems in the UK are:

Name

Approximate length (km)

Countries run through

Severn

354

Wales and England

Thames

346

England (South)

Tyne

321

England (North East)

Trent

298

England

Great Ouse

230

England (Centre)

Wye

215

Wales and England

Tay

188

Scotland

Spey

172

Scotland

Tweed

156

Scotland and England

Avon

154

England (Midlands and South West)

Glossary

1. carboniferous period

A geological period dating from 354 - 290 million years ago. It lasted approximately 64 million years.

2. constructive plate boundary

An area where two tectonic plates are moving away from one another.

3. glaciation

The build up of ice on the land during colder periods in time.

4. ice age

A time when parts of the Earth's surface were covered with large ice sheets.

5. igneous

Rocks that formed under very hot conditions within the Earth.

6. relief

The way that the landscape changes in height.

7. relief rainfall

Rain that occurs on high land and mountainous areas.

8. schist

A rough, coarse metamorphic rock. It has many layers of different minerals.

Geography - River processes (Edexcel) Quiz

1Which type of erosion is the sheer power of the waves hitting the river banks?

Abrasion

Hydraulic action

Solution

2Pebbles grinding along a rock platform is which type of erosion?

Abrasion

Hydraulic action

Solution

3Which of these describes saltation transportation?

Particles carried within the water

Pebbles rolling along the river bed

The bouncing movement of pebbles along the river bed

4Which of these describes traction transportation?

Particles carried within the water

Pebbles rolling along the river bed

The bouncing movement of pebbles along the river bed

5Where is deposition most likely to occur?

Shallow water

The river's source

A waterfall

6What is a drainage basin?

The area of high land forming a ridge around the river

Where the river begins

The area of land around a river

7What is a tributary?

Where the river flows

A small river that joins a larger river

The point where two rivers meet

8What is a long profile?

A line representing the river from its source to its mouth

A line representing one side of the valley to another

A sample of the river

9Which of these are characteristics of the upper course?

Wider and deeper channel

Shallow, narrow channel

Widest, deepest channel

10Which of these are characteristics of the lower course?

Wider and deeper channel

Shallow, narrow channel

Widest, deepest channel

Geography - River landforms (Edexcel) Quiz

1When do waterfalls occur?

When the river reaches the middle course

When there is hard rock on top of soft rock

When there is soft rock on top of hard rock

2What types of erosion cause the undercutting of a waterfall?

Abrasion and hydraulic action

Abrasion and attrition

Attrition and hydraulic action

3Which erosional landform creates land which links together?

Levees

Meanders

Interlocking spurs

4Where on a meander would you find a river cliff?

Outside bend

Inside bend

The centre of the channel

5Where on a meander would you find a slip-off slope?

Outside bend

Inside bend

The centre of the channel

6What is the name of the feature where a meander has been cut off from the river channel?

Levee

Estuary

Oxbow lake

7What is the shape of the valley in a floodplain?

Wide and flat

Narrow and flat

Wide and steep

8What is a levee?

The shape of the valley when vertical erosion has taken place

An erosional feature found on the outside bend of a meander

A natural embankment, built up when the river overflows

9Which landform occurs where the river meets the sea and becomes tidal?

Meander

Estuary

Oxbow lake

10High Force on the River Tees is which landform?

Waterfall

Levee

Oxbow lake

Geography - Human activities on rivers (Edexcel) Quiz

1Which of the following could cause flooding?

Flat valley

Impermeable rocks

Permeable rocks

2What is a hydrograph?

A graph to show how a river responds to flooding

A graph to show how much damage is caused by flooding

A graph to predict floods

3What is hard engineering management?

Building artificial structures to control rivers

A natural approach to control rivers

Using technology to monitor river flooding rates

4What is soft engineering management?

Building artificial structures to control rivers

A natural approach to control rivers

Using technology to monitor river flooding rates

5What is a disadvantage of a dam and reservoir?

It increases flood risk downstream

It doesn’t reduce flooding

It is expensive to build

6What is river dredging?

Making the river wider

Making the river deeper

Building up the banks of the river

7What is a disadvantage of flood warnings?

The equipment used is very expensive

Flash floods happen too quickly for a warning to be effective

People don’t listen to the warnings

8What is an advantage of floodplain zoning?

Expensive buildings are further away so there is less economic impact

It can easily be done in all existing built-up areas

Planning is simple as a standard model is followed

9Which of the following was not a physical cause of the floods in Cockermouth in 2009?

The steep-sided mountains surrounding the area

The tarmac and concrete surfaces of the town

The heavy relief rainfall

10Which of the following was a human cause of the floods in Cockermouth in 2009?

The ground was saturated from previous months of heavy rain

Cockermouth is the confluence where two rivers meet

The rivers in the area had not been dredged for several years

Geography - UK landscapes (Edexcel) Quiz

1What is relief?

The height of the ground above sea level

The way that the landscape changes in height

A lowland area

2What is an upland area?

A place which is high above sea level

A hilly place

A place with lots of open space

3What is a lowland area?

A place which is next to the sea

A place with lots of open space

A place which is not very high above sea level

4Through what process did ice shape the land?

Weathering

Glaciation

Erosion

5How do igneous rocks form?

As a result of volcanic activity

Along fault lines, under intense heat and pressure

Under the sea, as sand particles deposit and compress

6Where might you find granite in the UK?

In the south-east of England

In the south-west of England

In Norfolk

7Where is the lowest place in the UK?

Lincolnshire

The London Basin

The Fens in East Anglia

8What is the longest river in the UK?

River Severn

River Thames

River Tyne

9What is the relief (shape) of the landscape largely determined by?

Glaciation

Rivers

Both glaciation and rivers

10Where are the rivers Spey and Tay found?

Wales

Scotland

England

L. Jennings

changing... · web viewerosion, transportation and deposition all occur in a river. moving from the...

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