The Changing Landscapes of the UK and Coastal Landscapes and Processes

Name the 3 rock types

Sedimentary

Igneous

Metamorphic

Explain how Igneous Rocks are formed, and name examples.

Igneous rocks are formed from the solidification of magma after volcanic activity. Examples include granite and basalt.

Explain the distribution of UK rock types

In the northern regions of Scotland, namely Aberdeen, there is a high concentration of both igneous and metamorphic rock, and igneous rocks can be found mainly in upland areas, such as the Lake District and Snowdonia

Sedimentary rocks are found across lowland areas of southern central parts of England, as well as west of Dublin.

Explain how Sedimentary rocks are formed, and name examples.

Sedimentary rocks are formed from the accumulation of sediments and particles(sandstone), as well as the remains of plants and animals(limestone and chalk).

Explain how Metamorphic rocks are formed, and name examples.

1. Metamorphic rocks are formed when other rock types( such as igneous, sedimentary, and other metamorphic) are subjected to extreme heat and pressure.

2. Examples include marble and slate.

Explain what extrusive igneous rocks are.

Extrusive igneous rocks form on the surface of the Earth, through the solidification of magma after volcanic activity, and they cool much quicker than intrusive igneous rocks: why the crytals that grow on the surface of extrusive igneous rocks are much smaller than the crystals that grow on intrusive igneous rocks. Examples of extrusive igneous rocks include basalt

Explain what intrusive igneous rocks are.

Intrusive igneous rocks form beneath the surface of the Earth, through the solidification of magma after volcanic activity, and they cool much slower than extrusive igneous rocks: why the crytals that grow on the surface of intrusive igneous rocks are much bigger than the crystals that grow on extrusive igneous rocks. Examples of intrusive igneous rocks include granite

Explain one reason why areas of igneous rock are usually upland

Igneous rocks are more resistant rocks which means that they are less easily eroded

Explain one reason why areas of sedimentary rock are usually lowland

Sedimentary rocks are less resistant rocks which means that they are easily eroded

What imaginary line separates the UK into 2 halves?

The imaginary Tees-Exe line separates the UK into 2 halves- the North Western region and the South Eastern part.

Name the 4 types of coastal erosion.

Hydraulic action

Abrasion

Solution Remember HASA!

Attrition

Explain what Hydraulic Action is.

1. Hydraulic action is where waves crash against the cliff surface, and the force of this collision causes rocks and sediment to be dislodged.

2. The collision results in several air spaces and faults in the rocks to form.

3. When the wave retreats, the air spaces are released and cause an explosive reaction, resulting in more rock to be broken off.

Explain what Abrasion is.

Abrasion is the process where a plethora of rocks and pebbles are collected by waves and thrown across the cliff surface, causing more rock to be dislodged.

Explain what Solution is.

Solution is the chemical action on rocks by seawater. An example of this is calcium dissolving in the water when waves hit the surface of limestone.

Explain what Attrition is.

Attrition is where large pebbles and rocks, carried by waves, are hit against the cliff surface continually, and eventually end up as sand-sized particles.

Explain what weathering is.

Weathering is the breakdown of rocks at/near the surface of the ground.

Name the 3 types of Weathering.

Mechanical(freeze-thaw) weathering.

Chemical Weathering.

Biological Weathering.

Explain what Mechanical(Freeze-thaw) weathering is.

Mechanical(freeze-thaw) weathering is where water enters the cracks of rock, freezes, and expands overnight( by 10%). This general expansion causes the rock to dislodge and break down.

Explain what Chemical Weathering is.

Chemical weathering takes place when rainwater(relatively acidic) hits the surface of rocks, causing a weak chemical reaction, and resulting in the rock to break down.

Explain what Biological Weathering is.

Biological weathering occurs when the growth of plant roots causes rocks on the surface layer to break down.

Explain what mass movement is.

Mass movement is the downward movement of rock under the influence of gravity.

Name the 3 types of Mass movement.

Rock falls

Slumping

Sliding

Explain how rock falls take place.

1. Rock falls are where pieces of weathered rock fall down hills and slopes at increasing rates.

2. This is caused when the base of the hill/cliff is bombarded with waves, causing rocks to break off and the structure to weaken.

3. As a result of poor support from the base, the top of the structure breaks down.

Explain how slumping takes place.

1. Slumping takes place after heavy periods of rainfall.

2. Rainwater enters the permeable rocks, such as sandstone, and when impermeable rock meets permeable rock, the saturated soil and weaker rock slumps.

3. This leads to a downward movement of the fall.

Explain how sliding takes place.

1. Sliding is quite similar to slumping; however, the movement of rock is usually across a flat surface( such as a bedding plane).

2. This leads to the rockfall being much faster.

Explain what deposition is.

1. Deposition is where there is not enough energy to carry the eroded material, causing the deposited fragments to be laid down.

2. An example of this is the accumulation of sand in a bay to form a beach.

Explain what pastoral farming is.

Pastoral farming is the farming of livestolk

Explain what arable farming is.

Arable farming is the farming and cultivation of plants.

How are waves generated?

1. Waves are generated when winds blow over open seawater.

2. The friction with the surface of the water causes ripples to form, which then eventually transform into waves.

3. The energy of the wave and its ability to deposit material across the coastline depend on its height

Factors that affect wave height and energy.

Wind strength -->> The faster the rate at which the wind blows, the greater the friction on the surface of the water, and the bigger the wave size.

Wind duration -->> The period over which wind blows at

Fetch -->> The distance of open seawater over which where wind blows. The greater the fetch, the bigger the wave.

What is swash?

Swash is the surge of water that rushes up the beach until it runs out of energy.

What is backwash?

Backwash is the water that runs back down the beach under the influence of gravity.

Constructive waves info

Formed through weaker winds, over short fetch areas

Stronger swash than backwash

Low frequencies but long wavelengths

6-9 waves break per minute

Form wider and shallower beaches

Offer cliffs more protection from erosion because more

of the wave's energy is absorbed.

Low energy waves

Destructive waves info

Formed through strong winds over large fetch areas

Stronger backwash than swash

High frequencies, but short wavelengths

11-15 waves break per minute

If beaches form, they are narrow

Offer cliffs little protection from erosion because less energy is absorbed from the wave.

High energy waves

What are concordant coastlines?

Concordant coastlines are bands of resistant and less resistant rock that run parallel to the coastline.

What are discordant coastlines?

Discordant coastlines are bands of resistant and less resistant rock that run at right angles to the coastline.

How are headlands and bays formed?

Hydraulic action and abrasion erode sea cliffs. On a discordant coastline, these erosive processes occur at different rates because the rocks that form are of varying hardness and resistance.

The harder rocks erode much more slowly than weaker rocks and form features referred to as headlands( examples include The Foreland and Peveril Point).

The weaker rock erodes much quicker to form bays( Swanage Bay)

Extra info

1. Fewer headlands and bays form on the coastline because the rock types are similar, so the level of erosion is the same.

2. However, if hard rock encloses the outer region, then high cliffs form.

3. These bodies of land act as tough barriers, but when water breaches, much of the inner land( made of softer rock) erodes, forming a cove.

Definition of a cove.

A circular area of water, with a narrow entrance from the sea.

Why do resistant rock erode?

1. Erosive processes such as hydraulic action and abrasion contribute greatly to the gradual erosion of sea cliffs.

2. Therefore, resistant rocks can also be affected by these processes, which will eventually contribute to their breakdown by the sea.

Describe the formation of a wave-cut platform

Cliffs are formed when destructive waves attack the region between high and low water marks.

Erosive processes such as hydraulic action and abrasion undercut the cliff to form a wave cut notch.

The notch gets deeper, causing the overhanging cliff above to be unsupported, and eventually collapse.

The waves then clear away the rock and debris.

Again, the destructive waves begin to attack the newly formed cliff. Through continual erosive and weathering processes, the cliff is forced to retreat.

The newly formed rocky region is the wave cut platform. This platform remains hidden during high tide, but can be viewed during low tide. This region is not smooth because abrasion causes rock pools and cracks to form.

Explain how a cave is formed.

1. When destructive waves hit the surface of any headland, immediately, any lines of weakness in the rock are attacked( these include faults and joints).

2. Erosive processes such as abrasion and hydraulic action will cause these faults and joints to expand, forming a cave.

Explain how an arch is formed.

1. An arch is formed when a cave, created by wave erosion on a headland, extends and breaks through to the other side of the headland.

2. This creates an opening shaped like an arch.

Explain how a stack is formed.

1. Continued erosion of the arch causes it to widen. As the sea undercuts the base of the arch, more pressure is placed upon the top end of the arch.

2. This pressure continues to build until the top half collapses- forming a stack.

Explain how a stump is formed.

Further erosive and weathering processes cause the stack to collapse and form a flat stump. This feature remains hidden during high tide.

Explain the process of longshore drift.

Waves carry rocks and pebbles to the coast.

Longshore drift is the process of transportation of rocks and pebbles to the coast.

When waves reach beaches, they arrive at angles.

The swash of the wave deposits material onto the beach at the same angle as the wave.

The backwash of the wave takes in material and retreats at right angles to the coastline.

Essentially, however, the direction of waves is determined by prevailing wind.

For example, along the Dorset coastline, the prevailing south-westerly wind causes the waves to move from west to east.

Provide the definition of Longshore drift.

Longshore drift is the process of transportation of rocks and pebbles to the coastline.

What is a berm

A berm is a ridge of shingles and sand.

Please explain the formation of a beach.

Beaches are formed through constructive waves( because they have a stronger swash than backwash), deposit a greater quanity of material onto the region.

Over time, these deposits, rocks, pebbles, and sediments accumulate to form a beach.

Sand beaches are usually based in sheltered bays( these are referred to as bay head beaches).

These beaches are much narrower than pebble beaches and open up gently towards the seawater.

Pebble beaches are mainly found near retreating cliffs. Essentially, though, most of the content of these beaches derives from the rock and debris from the eroding cliff faces.

Describe the profile of a beach.

The profile(cross-section) of a beach is rarely smooth.

In the alleviated region, you may locate a storm surge made up of merely boulders and shingle deposited by only the largest waves.

Below this, you find a ridge of shingles and sand, referred to as a berm.

A collection of berms marks the normal tide.

The smallest material( sand) is deposited close to the sea.

What is a spit

A spit is a long, narrow region formed of sand or shingle.

One part of this feature is connected to land, whereas the remaining half projects out to sea.

If the spit is comprised of sand, dunes are located at the landward side of the feature.

Additionally, the landward side of a spit is sheltered, welcoming deposits of silk and mud to form a salt marsh.

Please explain the formation of a spit.

The formation of a spit is similar to that of a beach.

Sediments and materials are continually deposited along the coastline by longshore drift.

This process repeats several times until a ridge shape is formed. Freshwater and seawater are trapped behind this feature.

The continuation of the ridge occurs until pressure from the wind and bombardment from the waves causes the shape to bend. This is why the structure of a spit is loopy and bent.

What is a formation of a bar

A bar is a ridge of sand or shingle across the mouth of a bay or river, connecting two headlands or enclosing a lagoon.

Formed through longshore drift: sediment is transported along the coast and deposited when waves lose energy.

Deposition continues, gradually building a ridge across the bay/river mouth.

The landward/sheltered side is calm, allowing silt and mud to accumulate, forming a lagoon or salt marsh.

The seaward side faces the open sea.

Differs from a spit because it completely joins two headlands or encloses water, rather than extending from one point of land.

What coastal landforms( in OS maps) would be landward for High water Marks?

Sand dunes and cliffs.

What coastal landforms( in OS maps) would be seaward for High water Marks?

Wave-cut platforms and beaches

What is coastal erosion and recession?

Coastal erosion is the process by which sediment and material are removed along the coastline, causing the region to retreat inland.

Coastal recession refers to the retreat of the coast inland.

What are the causes of rising sea levels?

Sea levels along the English Channel have risen by 12cm in the past 100 years. Levels are expected to increase by 11-16cm by 2030. Global warming causes the sea to expand and enlarge, as well as the ice sheets to melt and break away. This leads to rising sea levels, and the effects are as follows.

Cliffs that are collapsing will continue to retreat inland, and the positions of wave-cut notches and platforms may change.

Much softer regions( made from clay and other weaker rocks) will experience erosion at a much faster and greater rate.

What is a storm surge?

A storm surge is a large-scale increase in the level of seawater( up to 3m in the UK) as strong gale winds direct the water towards the coastline, causing great damage to life and infrastructure. This can occur from hours to days, and can span over 100s of kilometers.

What happened in the 1953 North Sea Storm surge?

The 1953 North Sea storm surge was one of the most brutal flood-related events (in the UK) in the 20th Century. Areas such as Lincolnshire were affected greatly, with 307 deaths in England alongside 24000 properties and 65000 hectares of land being damaged.

Explain 4 land uses that have been affected by erosion.

Settlements- 20 million individuals( in the UK) live along the coastline. In Holderness, for example, 29 villages have been lost to storms and rising sea levels in the past 1000 years.

Infrastructure- Roads, oil refineries, and factory buildings are all mostly based around the coastline. This is because of the large perimeters of unused land to build upon. For example, the petroleum firm Esso holds the UK's largest oil refinery near Southampton.

Agriculture- Already, large hectares of agricultural land have been lost to erosion. 2.2 million tonnes of topsoil are continuously lost annually. Considering that topsoil is the part of the soil that is the richest in nutrients, consider the number of plants and trees that could have been planted.

Tourism- Tourism plays an influential role in the economic development of coastal areas. For example, in Dawlish, 13% of the total employment derives from tourism.

What is Defra, and its purpose?

The Department for the Environment, Food, and Rural Affairs( Defra) is responsible for protecting and conserving the UK coastline. The Department does this by choosing which part of the coastline to protect, and how.

What is the Shoreline Management Plan(SMP)?

To make the process of conservation easier, the coastline is separated into segments. The Environment Agency and local authorities are then responsible for protecting their coast by deciding on what policies to implement. Together, they are the Shoreline Management Plan( SMP).

What are the goals of the SMP?

To protect the environment and humans from the risk associated with flooding.

To improve the society, economy, and environment by following the Government's sustainable policies.

What are the 4 possible plan policies?

1. Hold the Line- Maintain the existing shoreline by building defences.

2. Advance the Line- Build new defences on the seaward side.

3- Managed realignment- Allow the shoreline to change naturally, but direct the process.

4. No intervention- No planned investment in protecting the shoreline against erosion and flooding.

What policy is implemented the most?

In most cases, the policy to "hold the line" is implemented. Authorities have the option between soft and hard engineering.

What is soft engineering?

The practice of soft-engineering is a more natural approach to protecting the coastline from erosion and flooding. This procedure allows the processes to work and the land to change into an environmentally sustainable region.

What is beach nourishment?

Beach nourishment( recharge) is a soft-engineering technique. This process involves adding sand or shingle to a beach to make it higher or wider.

What are the advantages of beach nourishment( or recharge)?

1. The newly altered beach can absorb more of the waves' energy, preventing further destruction to the landforms behind.

2. The sand and shingle are collected from the seabed by a dredge. This ensures that the beach continually looks natural.

3. The wider beach that is formed attracts tourists. This then improves the local economy.

What are the disadvantages of beach nourishment( or recharge)?

1. Requires constant maintenance, which can later become expensive.

2. The majority of the process occurs in the summer, and as this is the season when most people come to beaches, it can disrupt tourists.

What is sand dune regeneration?

Sand dune regeneration involves the planting of grasses, bushes, and trees to stabalise dunes.

What are the advantages of sand dune regeneration?

Helps the dunes to develop while maintaining the natural coastal environment

A relatively cheap process

Popular with people and wildlife.

What are the disadvantages of sand dune regeneration?

Fences areas of beaches, prohibiting access.

Takes long periods for dune vegetation to establish.

What is hard engineering?

Hard engineering involves building artificial defences, usually made of concrete, to interrupt natural processes and dissipate wave energy, to prevent damage to the coastline.

What are examples of hard engineering?

Rip rap( rock armour)

Groynes

Sea walls

What are sea walls?

Sea walls are concrete structures that are usually 3-5 metres tall. These walls are usually built at the foot of cliffs and the top of beaches. These structures are curved in shape to reflect the water into the sea.

What are the advantages of sea walls?

1. Sea walls have walkways and promenades.

2. They are effective at stopping seawater.

3. Curved in shape to reflect water into the sea.

What are the disadvantages of sea walls?

1. Sea walls can be obtrusive and unnatural to look at.

2. They can prevent access to beaches.

3. They can cause erosion on beaches.

4. They are very expensive to build and maintain.

Please explain the disadvantages and advantages of sea walls.

Please type your answer.

What are groynes?

Groynes are wooden or rock structures built at right angles to the sea.

What are the advantages of groynes?

1. They are quick to build.

2. Groynes trap sediment, allowing the beach to widen and absorb more of the wave energy.

3. Wider beaches attract more tourists, welcoming an increase in economic growth to the area

What are the disadvantages of groynes?

The trapping of sediment can have great impacts along the coastline. This is because it can prevent the growth of other beaches.

Rock groynes are unsightly.

Please explain the disadvantages and advantages of groynes.

Please provide your answer.

What is rip rap( rock armour)

Rip rap( rock armour) is piles of large boulders stacked at the foot of cliffs and the tops of beaches.

What are the advantages of rip rap( rock armour)?

1. Quick and easy to put in.

2. Relatively cheap to maintain.

3. The large boulders dissipate most of the wave energy, protecting the cliffs and coastline behind

What are the disadvantages of rip rap( rock armour)?

1. The large boulders are imported from foreign places, so transport costs are high.

2. Do not fit in with the local geology.

3. Impede access to beaches.

What are the advantages and disadvantages of rip rap( rock armour)?

Please provide your answer.

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