The UK physical landscape Flashcards
1
Q
Explain Snowdonia.
A
Glaciated upland area formed from rock from extinct volcanoes. It contains steep mountains, such as Snowdon and glaciated valleys.
2
Q
Explain the Cheshire plain.
A
An area of low, flat land formed by the deposition of material eroded by glaciers, this land is very fertile and is mainly used for dairy farming.
3
Q
Explain the Grampian mountains.
A
Part of the highlands and home to Ben Nevis and are steep, rocky and sparsely populated.
4
Q
Explain the downs and the weald.
A
A lowland area with a wide valley situated between the parallel hills of the downs. The area is no mainly agricultural.
5
Q
What does rock type depend on?
A
How they were formed.
6
Q
What is igneous rock?
A
Formed when molten rock (magma) from the mantle cools down and hardens. The rock forms crystals as it cools. Igneous rocks are usually hard such as granite.
7
Q
What are sedimentary rocks?
A
Formed when layers of sediment are compacted together until they become solid rock. There are two main types in the UK.
8
Q
What is the first type of sedimentary rock?
A
Carboniferous limestone and chalk are formed from tiny shells and skeletons of dead sea creatures. Limestone is quite hard, but chalk is much softer.
9
Q
What is the second type of sedimentary rock?
A
Clays and shales are made from mud and clay minerals. They are very soft.
10
Q
What are metamorphic rocks?
A
Metamorphic rocks are formed when other rocks (igneous, sedimentary or older metamorphic rocks) are changed by heat and pressure. The new rocks are harder and more compact. For example shale becomes slate and slate can become schist with further heat and pressure.
11
Q
What are the three main ways that tectonics shaped the UK landscape?
A
Active volcanoes, plate collisions and plate movements.
12
Q
How did active volcanoes shape the UK?
A
Land that now makes up the UK used to be much closer to a plate boundary than it is now. Active volcanoes forced magma through the Earth’s crust which cooled to form igneous rocks such as granite.
13
Q
How did plate collisions shape the UK?
A
Caused rocks to be folded and uplifted forming mountain ranges. Many of these areas remain as uplands such as the Scottish Highlands or the Lake District and north Wales. The igneous granite is hard and more resistant to erosion. Secondly, the intense heat and pressure caused by plate collisions formed hard metamorphic rocks in northern Scotland and northern Ireland.
14
Q
How did plate movements shape the UK landscape?
A
Britain was in tropics and was partly underwater due to sea levels. Carboniferous limestone formed in the warm shallow seas. This can be seen in the uplands of Peak District in northern England. The youngest rocks in the UK are the chalks and clays found in southern England. They formed in shallow seas and swamps and form lowland landscapes. Softer and easily eroded.
15
Q
Where are igneous and metamorphic rocks found?
A
North and west of UK.
16
Q
Where are sedimentary rocks found?
A
South and east of UK.
17
Q
What are the characteristics of Granite?
A
Very resistant and forms upland areas, lots of joints (cracks) which are not evenly spread so rock can stick out and form tors. Granite is impermeable which creates moorlands (large areas of waterlogged land and acidic soil with low-growing vegetation).
18
Q
What are the characteristics of slate and schist?
A
Slate forms in layers creating weak planes in the rock, slate is very hard and resistant to weathering but can split easily into thin slabs. Schist has bigger crystals than slate and also splits easily into small flakes. These both form rugged, upland landscapes and are impermeable.
19
Q
What are the characteristics of carboniferous limestone?
A
Rainwater eats away at limestone through carbonation weathering along joints which can create caverns and gorges. Limestone is permeable so it creates dry valleys and resurgent rivers (rovers that pop out at the surface when limestone is on top of impermeable rock).
20
Q
What are the characteristics of chalk and clay?
A
Chalk is harder than clay, it forms escarpments (hills) in UK lowlands and cliffs at the coast. One side of the hill is usually steep and one side is usually more gentle. Chalk is permeable so water flows through and emerges as a spring where it meets impermeable rock. Clay is soft and easily eroded which forms wide flat valleys in UK lowlands and it is impermeable so water flows over the surface so many streams rivers and lakes.
21
Q
How was the UK’s landscape influenced by ice?
A
Parts of UK covered in massive ice sheet, ice is very powerful so it was able to erode the landscape, carving out large U-shaped valleys in upland areas such as the lake district. Glaciers also deposited lots of material as they melted. Landscape formed by glacial meltwater and deposits extend south of the ice sheets.
22
Q
What is weathering?
A
Breakdown of rock into smaller pieces. It can be mechanical, chemical or biological.
23
Q
What is erosion?
A
Wears away rock.
24
Q
Explain how post-glacial river processes alter the landscape?
A
Melting ice at the end of glacial periods made rivers much bigger with more power. Also left distinct landforms when it melted such as hanging valleys.
25
Explain how slope processes alter the landscape.
Mass movements such as rockfalls, slides, slumps and soil creep.
26
How can climate affect physical processes?
Cold climate increases likelihood of freeze-thaw weathering and a wet climate increases number of streams and rivers.
27
How did physical processes interact to make distinctive upland landscapes?
Ice can hollow out corries and freeze thaw weathering can occur on the steep back wall of the corrie causing the rocks to break up, causing rock falls and forming scree. Ice can erode U-shaped valleys. Impermeable rock causes streams that cause erosion.
28
How did physical processes interact to form distinctive lowland areas?
Dry valleys with no streams as they flow underground in the permeable chalk. They formed in glacial periods when the colder climate led to more freeze thaw weathering and glacial snow melt. Wet climate leads to flooding and can overflow the river and deposit silt causing flood plain.
29
How have humans changed the landscape through agriculture?
People have cleared the land of forest to make space for farming, overtime walls have been put in to mark out fields.
30
What are the different landscapes and what type of farming are they good for?
Arable-Flat with good soil used for arable farming (growing crops).
Dairy-Warm and wet areas are good for dairy farming. Lots of large, grassy fields.
Sheep-Sheep farming takes place in the harsher conditions in the uplands as sheep are well suited to upland landscapes as they can cope with steep slopes and cold weather. Sheep farming led to lack of trees on hills as young trees are eaten or trampled so cannot grow.
31
How has forestry changed the landscape?
Forestry is the management of areas of woodland and can be used for timber, recreation or conservation. Little woodland now. Coniferous (evergreen) forests have been planted for timber. The trees are often planted in straight lines as they do not have to look natural. In other areas deciduous woodland is being replanted to make the area natural.
32
How is settlement affecting the landscape?
Water supply needed for early settlers and easily defended. Land concreted, rivers diverted through underground channels and some river channels straightened or had embankments to prevent flood.
33
What is mechanical weathering?
Breakdown of rock without changing its chemical composition. There is one main type that affects coasts which is salt weathering.
34
What is the process of salt weathering?
Seawater gets into cracks in the rock and when the seawater evaporates, salt crystals form and as the salt crystals form they expand which puts pressure on the rock. Repeated evaporation widens the cracks and can cause it to break.
35
What is chemical weathering?
Breakdown of rock by changing its chemical composition. Carbonation weathering is a type of chemical weathering that happens in warm and wet conditions.
36
What is the process of carbonation weathering?
Seawater and rainwater have carbon dioxide dissolved in them which makes them weak carbonic acids which react with rock that contain calcium carbonate. For example carboniferous limestone, so the rocks are dissolved by the rainwater.
37
What is biological weathering?
Breakdown of rock by living things, for example plant roots break down rocks by growing into cracks on their surface and pushing them apart.
38
What is mass movement?
When material falls down a slope. Shifting of rocks and loose material down a slope and it happens when the force of gravity acting on a slope is greater than the force supporting it. This causes coasts to retreat rapidly. They are more likely to happen when the material is full of water as it acts as a lubricant and makes the material heavier.
39
What are the three types of mass movemnt?
Slides-Material shifts in a straight line
Slumps-Material shifts with a rotation
Rockfalls-Material breaks up and falls down a slope
40
How do waves wear away the coast through hydraulic action?
Waves crash against rock and compress air in the cracks which puts pressure on the rocks. Repeated compression widens the cracks and makes bits of rock break off.
41
How do waves wear away the coast through abrasion?
Eroded particles in the water scrape and rub against rock removing small pieces.
42
How do waves wear away the coast through attrition?
Eroded particles in the water smash into each other and break into smaller fragments. There edges also get rounded off as they rub together.
43
What are joints and faults?
Cracks and weaknesses in the rock which cause the rock to erode quicker.
44
Explain concordant coasts.
Alternate bands are parallel causing less erosional landforms.
45
Explain discordant coasts.
Bands perpendicular causing more bays and headlands as the bands of rock are eroded at different rates.
46
How does the UK's climate impact the coastal erosion and retreat?
Higher temp increases salt weathering as water evaporates quicker. Storms create destructive waves which increases erosion. Heavy erosion saturates soil and can cause mass movement. The prevailing (most common) winds can bring storms.
47
Explain destructive waves.
Waves that carry out erosional processes, they are high frequency, high and steep. There backwash is more powerful than their swash so material is removed. Storms increase erosional power which increases rates of retreat.
48
How do waves erode cliffs to form wave cut platforms?
Waves cause the most erosion at the foot of the cliff which forms a wave-cut notch which largens. The rock above becomes unstable and collapses and the material washes away. Repeated collapsing causes the cliff to retreat.
49
How are headlands and bays formed along discordant coastlines?
Hard rocks have more resistance compared to soft rocks. Headlands and bays form where there are alternating bands of hard and soft rock. The soft rock erodes and causes a bay whereas the hard rock sticks out forming a headland.
50
How are headlands eroded to form caves, arches and stacks?
Waves crash into the headlands and enlarge the cracks through hydraulic power and abrasion. Repeated erosion causes a cave to form. The cave is deepened until it breaks through forming an arch. Erosion continues to wear away the rock supporting the arch until it collapses. This forms a stack which is an isolated rock that is seperate from the headland. For example old harry in Dorset.
51
How is material transported along coasts through longshore drift?
Waves follow the direction of the prevailing wind. They hit the coast at an oblique angle and the swash carries material up the beach but the backwash carries material backwards at a right angle. Overtime zig zags from.
52
How do constructive waves deposit material?
Deposition is when material being carried by the sea water is dropped on the coast. Waves that deposit more than they erode are constructive waves. The swash is powerful but the backwash is less powerful. This can form beaches, they are less frequent.
53
What are spits?
They form at sharp bends, for example a river mouth. Longshore drift transports sand and shingle past the bend and deposits it in the sea. Strong winds and waves can curve the end of the spit forming a recurved end. The sheltered area behind a spit is protected from waves so material accumulates and can form plants. Over time the protected area can form a mud flat or a salt marsh.
54
What are bars?
A bar is formed when a spit joins two headlands together. The bar cuts off the bay between the headlands from the sea. This means a lagoon can form behind the bar.
55
What are wave cut platforms shown as?
Bumpy edges along the coast.
56
What are cliffs shown as on the map?
Little black lines.
57
What are beaches shown as?
Yellow and if there are black spots it is a shingle beach instead of sand.
58
What are indirect effects?
Effects as a result of direct effects.
59
How has agriculture affected the coast?
Agricultural land has low economic value which means it is often left unprotected so erosion can happen. Vegetation helps to bind the soil together and stabilise clifftops but clearing vegetation from grazing can expose the soil and leave it vulnerable to weathering. Marshland is sometimes reclaimed and drained for agricultural use. This reduces natural flood barrier.
60
How dose development affect the coast?
Costal areas are popular places to live and work so they often have lots of development. For example hotels. Costs with lots of settlement may have more coastal defences to protect businesses and homes. However this could cause change in transportation of material. This can make beaches further down narrower which leaves them more vulnerable to erosion.
61
How does industry affect the coast?
Coastal quarries expose large areas of rock. Gravel is extracted from some beaches for use in the construction industry for making concrete. This has removed material from the coast and increased the risk of erosion as there is less material to protect the cliffs. Industrial growth at ports, increased pressure to build on salt marshes as they are flat but this removes the natural flood barrier.
62
How does coastal management affect the coast?
Protecting coastal landscapes from erosion. Some strategies alter sediment movement which reduces protection further along the coast. It also prevents landscape from changing.
63
How does rising sea levels increase risk of flooding?
Threat to low lying coastal areas. Increase in sea levels could cause higher tide that would flood coastal areas more frequently. Higher tides could also remove larger amounts of material from beaches causing increased erosion as there is less material for protection. Could expose more of the coastline to erosion and beaches could become narrower which is bad.
64
How does storm frequency affect risk of coastal flooding?
Climate change is causing storms to become more frequent. Storms give the sea more erosional power. The sea will also have more energy to transport material. High energy waves can move more material further which could leave some areas being starved of material causing them to be more vulnerable. Storm surges could become more frequent and sea levels rising could cause surges to reach further inland.
65
What are the threats to the people from coastal flooding?
Low lying areas could be permanently flooded or flood so often it is impossible to live there. Coastal industries may be shut down. Damage to infrastructure. Could reduce tourism and some places rely on tourism.
66
What are the threats to the environment from coastal flooding?
Ecosystems could be affected as sea water has a high salt content so it can kill organisms or damage them. It can also reduce soil fertility. The force of floodwater can uproot trees and plants and can drown some trees and plants. If bars are destroyed lagoons would be destroyed.
67
What is hard engineering?
Man made structures built to control the flow of the sea and reduce flooding and erosion.
68
What is soft engineering?
Schemes set up using knowledge of the sea and its processes to reduce the effects of flooding and erosion.
69
What are the two hard engineering techniques?
Sea wall and groynes.
70
Explain sea walls.
Wall made out of hard material like concrete that reflects waves. It prevents erosion and flooding. Creates strong backwash which erodes under the wall and they are very expensive to build and maintain.
71
Explain groynes.
Wooden or stone fences built at a right angle to the coast. They trap material transported by longshore drift. They create wider beaches which slow the waves and gives greater protection from flooding and eroding. They are also fairly cheap. They starve beaches further down the coast of sand, making them narrower so they do not protect the coast as well. This leads to greater erosion and floods.
72
What are the three soft engineering techniques?
Beach replenishment, slope stabilisation and strategic realignment.
73
Explain beach replenishment.
Sand and shingle from elsewhere are added to the upper parts of beaches. This creates wider beaches which slows the waves. This gives greater protection from flooding and erosion. Taking material from the seabed can kill organisms like sponges and corals. It is very expensive and has to be repeated.
74
Explain slope stabilisation.
Slopes are reinforced by inserting concrete nails into the ground and covering the slope with metal netting. This prevents mass movement by increasing strength. It is very expensive and difficult to install.
75
Explain strategic realignment.
Removing an existing defence and allowing the land behind it to flood. Overtime the land will become marshland, creating new habitats. Flooding and erosion are reduced behind the marshland. People may disagree over what land is allowed to flood.
76
What is the option of doing nothing?
Costs nothing but people may be forced to move and infrastructure may be destroyed.
77
What do coastal management strategies need to be?
Sustainable which makes sure erosion and flooding are controlled without causing more problems.
78
What is integrated coastal zone management?
ICZM is an approach that aims to protect the coast while taking everyone's interests into account. this makes it easier to find solutions that people can all agree on. It is also long term so can be adapted to any future needs and changes along the coastline.
79
What is the course of the river?
The path of the river as it flows downhill.
80
What does the long profile show?
How the gradient changes over the different courses.
81
What does the cross profile show?
The cross section of the river.
82
What is the profile of the river like in the upper course?
Stee[, v-shaped valley, steep sides, narrow, shallow.
83
What is the profile of the river like in the middle course?
Medium gradient, gently sloping valley sides, wider and deeper channel.
84
What is the profile of the river like in the lower course?
Gentle gradient, very wide, flat valley, very wide and deep channel.
85
Explain vertical erosion.
Deepens the river valley and channel making it v-shaped. It is dominant in the upper course. High turbulence causes the rough , angular particles to be scraped along the river bed causing intense downwards erosion.
86
Explain lateral erosion.
This widens the river valley and channel during formation of meanders, it is dominant in the middle and lower course. Remember lateral and vertical can happen at the same time.
87
Give an example of a river.
The river Eden.
88
What type of weathering is freeze-thaw weathering and what is it?
Mechanical. Happens when the temperature alternates above and below 0 degrees. Water gets into rock that has cracks such as granite. When the water freezes it expands, which puts pressure on the rock. When the water thaws it contracts, which releases the pressure on the rock. Repeated freezing and thawing widens the cracks and causes the rock to break up.
89
What are the four processes of erosion?
Hydraulic action, abrasion, attrition, solution.
90
What is hydraulic action (river).
The force of the water breaks rock particles away from the river channel.
91
What is abrasion (river).
Eroded rocks picked up by the river scrape and rub against the channel, wearing it away. Most erosion happens by abrasion.
92
What is attrition (river).
Eroded rocks picked up by the river smash into each other and break into smaller fragments. There edges get rounded off and the further it travels, the more eroded it gets. This causes particle sizes to decrease downstream.
93
What is solution (river).
River water dissolves some rock types like chalk and limestone.
94
What are the four process of transportation?
Traction, suspension, saltation, solution.
95
What is traction?
Large particles like boulders are pushed along the river bed by the force of the water.
96
What is suspension?
Small particles like silt and clay are carried along by the water.
97
What is saltation?
Pebble-sized particles are bounced along the river bed by the force of the water.
98
What is solution?
Soluble materials dissolve in the water and are carried along.
99
What is river deposition?
When a river drops the eroded material it is transporting. it happens when a river loses velocity.
100
What are the reasons for a river slowing down and depositing material?
The volume of water in the river falls, the amount of eroded material in the water increases, the water is shallower like on the inside of a bend and the river reaches its mouth.
101
Where are waterfalls and gorges found?
In the upper course of a river.
102
How are waterfalls caused?
They form where a river flows over an area of hard rock followed by soft rock. The softer rock is eroded by hydraulic action and abrasion causing a step down. As water goes over the step it erodes more and more. A steep drop is created called a waterfall. The hard rock is eventually undercut and becomes unsupported so it collapses. The collapsed rocks are swirled around at the foot of the waterfall where they erode the softer rock by abrasion. This is called a plunge pool. Over time more undercutting causes more collapses so the waterfall will retreat leaving a steep sided gorge.
103
How do interlocking spurs form?
In the upper course of a river most of the erosion is vertical so v-shaped valleys are created. The rivers are not powerful enough to erode sideways so they have to wind around the high hillsides. The hillsides that interlock with each other as the river winds around them are called interlocking spurs.
104
What are meanders formed by?
Erosion and deposition.
105
How are meanders formed?
They form in the middle and lower course. The current is faster on the outside of a bend as it is deeper and less friction. This means more erosion happens forming river cliffs. The eroded material is deposited on the inside forming slip-off slopes.
106
How do oxbow lakes form from meanders?
Meanders get larger. Erosion causes the outside bends to get closer. This happens until there is only a small bit of land left between the bends called a neck. The river breaks through this land usually during a flood. The river flows along the shortest course so deposition eventually cuts off the meander. This forms an oxbow lake.
107
What are flat areas of land that floods?
The flood plain is the wide-valley floor on either side of a river which occasionally gets flooded. When a river floods onto the flood plain, the water slows down and deposits the eroded material that it is transporting. This builds up the floodplain and makes it higher. Meanders migrate across the flood plain making it wider, They also migrate downstream flattening the valley floor. The deposition that happens on the slip-off slopes of meanders also builds up the flood plains.
108
What are levees?
Levees are natural embankments (raised bits) along the edges of a river channel. During a flood eroded material is deposited over the whole flood plain. The heaviest material is deposited closest to the river channel as it gets dropped first when it slows down. Over time the deposited material builds up creating levees.
109
What are deltas?
Deltas are low-lying areas where a river meets the sea or lake. Rivers are forced to slow down when they meet the sea or lake. This means they deposit all the material. If the sea does not wash it away it will build up and the channel gets blocked forcing it to split up into small rivers called distributaries. Eventually it builds up so much deltas are formed.
110
How does climate affect river landscapes?
Rivers in wetter climates have more discharge which increases the erosion, more volume means more power to erode which adds material. Causes v-shaped valleys in the upper course and a wide flat flood plain in the lower course. Transportation increases as the river has more energy.
111
How does geology affect the river landscape?
Rivers flowing through hard rock have slower rate of erosion so the sediment load will be smaller. Hard rock landscapes will have steeper valley sides. Interlocking spurs form where softer rock is eroded first leaving hard rock to stick out.
112
Talk about resistance rather than hard and soft.
Thanks mark xxxxxx!!
113
How do slope processes affect the river landscape?
Vertical erosion makes steeper valley sides increasing movement of material. Mass movements can add large amounts of material to the rivers load. Mass movements are more likely in cold weather (freeze-thaw weathering loosens material). Levels of saturation. Soil creep is when soil particles move down a slope because of gravity. It's caused by expansion and contraction of the soil. Water adds weight to the soil and makes it expand. This causes it to move down the slope. Soil creep can add fine material to river load.
114
What is river discharge?
Volume of water that flows in a river per second and is measured in cumecs-m^3/s. Storm hydrographs show the changes in a rivers discharge around the time of a storm.
115
What is lag time?
The delay between peak rainfall and peak discharge.
116
What is rising and falling limb?
The increase/decrease in the river discharge as rainwater flows in or as it returns to its normal level.
117
What is runoff?
Surface runoff is quicker.
118
What is infiltration?
Rainwater soaking into the ground.
119
Why do we get lag time?
Because rainwater doesn't fall directly into the river.
120
How does geology affect the hydrograph?
Water cannot infiltrate into impermeable rocks so there is more runoff which reduces the lag time.
121
How does soil type affect the hydrograph?
More impermeable soils like clay cannot absorb as much water as sandy soils which increases runoff and therefore reduces lag time. Shallower soils saturate easier.
122
How does the slope affect the hydrograph?
The steeper the slope, the less infiltration and the higher the runoff.
123
How does drainage basin type affect the hydrograph?
Circular drainage basins have a shorter lag time and higher discharge than narrow basins as water reaches the main river channel at the same time. In a narrower basin water from the far end takes ages to reach the main channel.
124
How do antecedent conditions affect the hydrograph?
Previously wet or very cold weather can increase runoff because water can't infiltrate saturated or frozen soil.
125
How does urbanisation affect the hydrograph?
Water can't infiltrate into impermeable surfaces like concrete or tarmac so there is more runoff, gutters and drains quickly take runoff to rivers which rapidly increases discharge.
126
How does deforestation affect the hydrograph?
Trees take up water from the ground and store it which reduces runoff, cutting down trees increases runoff and causes more water to enter the river channel which increases discharge.
127
What are the threats from river flooding on people?
People can be injured or killed. Roads bridges and rail lines can be damaged or destroyed. Flood water is often contaminated with sewage which can lead to a lack of clean drinking water. Possessions can be damaged or washed away. People can be made homeless as their properties are inundated or damaged. Businesses may be forced to shut down as their properties are inundated or damaged. Businesses may be forced to shut down because of flood damage and disrupted power supplies. This leads to a loss of livelihoods.
128
What are the threats of river flooding to the environment?
Floodwater can be contaminated with sewage and rubbish can pollute rivers, damaging habitats. Farmland can be ruined by silt and sediment deposited by a flood. River banks are eroded causing huge changed to the river landscape. The force of the water can uproot trees or standing floodwater can kill vegetation.
129
What are hard engineering techniques (rivers).?
Man made structures built to control the flow of rivers and reduce flooding.
130
What are soft engineering techniques?
Schemes set up using knowledge of a river and its processes to reduce the effects of flooding.
131
What are the 4 hard engineering techniques for rivers?
Flood walls, embankments, flood barriers (floodgates) and flood barriers (demountable).
132
What are floodwalls?
Artificial barriers built along river banks. They are designed to increase the height of river banks allowing the river channel to hold more water. They are very expensive and unsightly.
133
What are embankments?
High banks built along or near a river near the river banks. They stop the river flowing into built-up areas during a flood, can be built of earth making them less unsightly while still protecting the flood plain. Quite expensive to build and risk of severe flooding..
134
What are flood barriers (floodgates)?
Built on river estuaries to stop flooding from storm surges or very high tides. They can be shut when there's a surge forecast to prevent flooding and they protect a large area of land, Very expensive and need to me maintained regularly.
135
What are flood barriers (demountable)?
Demountable flood barriers provide temporary protection against flooding. The barriers are only put up when there's a flood forecast so they might not be put up in time. Quite expensive but don't spoil landscape.
136
What are the two soft engineering techniques for rivers?
Flood plain retention and river restoration.
137
What is flood plain retention?
This strategy involves maintaining the river's flood plain by not building on it. It helps slow floodwater and maintains the flood plain. It is free but restricts development and cannot be used in urban areas.
138
What is river restoration?
Making river more natural by removing man made levees so the flood plain can flood naturally. Less risk of flooding downstream as discharge reduced. Little maintenance needed but can increase local flood risk.
