TJNOTES
AQA GCSE Geography Paper 1 notes,
Section C : Physical landscapes in the UK
PAPER, I
SECTION C
Waves
• As wind blows over the surface of the sea, waves are formed
• The greater the fetch (distance travelled), the more powerful (higher energy) the
wave
There are two types of waves:
(1) Constructive
• These waves deposit material because they have a low frequency and are low in
energy
• Because they have a strong swash (water moving up the beach) and a weak
backwash (water moving down the beach), material is deposited
• Constructive waves are low in energy, have a low height and have a low
frequency
• They are formed in calm conditions and low wind speeds
(2) Destructive
• These waves erode the coast because they have a weak swash and a strong
backwash, causing sediment to be removed
• They have a high frequency, are high in energy and they are tall
• They are formed in stormy conditions and high wind speeds
Weathering
• Rock can be broken down by mechanical and chemical weathering
• The definition of weathering is: the breaking down of rock
• Mechanical weathering breaks down rock without changing its chemical
composition and the main mechanical weathering that takes place is freeze-thaw
weathering which takes place in the process:
• (1) Water enters the cracks in a rock
• (2) Water freezes and expands, putting pressure on the rock
• (3) When it thaws, it contracts, releasing pressure on the rock and, as this
process repeats, the freezing and thawing widens the crack and causes the rock
to break up
• Chemical weathering is the breakdown of rock by changing its chemical
composition
,TJNOTES
• Carbonation is a type of chemical weathering that takes place in warm and wet
conditions as carbon dioxide dissolved in rainwater makes it a weak carbonic
acid
• As the carbonic acid then reacts with rock that contains calcium carbonate
(limestone), rocks are dissolved by the rainwater and are broken down
Mass Movement
• Mass movement is when material, mud and rock fall down a slope due to the
force of gravity acting on the rock
• Mass movement causes the coast to retreat rapidly and it is more likely to take
place when material is full of water because water acts as a lubricant and makes
the material heavier
There are 3 processes of mass movement:
(1) Sliding
• This is when mud and blocks of rock shift and slide in a straight line along a slide
plane
(2) Slumping
• When material (usually saturated soil and weak rock) rotates along a curved slip
plane
(3) Rockfalls
• Material breaks up, often along bedding planes and falls down the slope as
crumbled rock
Processes of erosion
• Erosion is the WEARING DOWN of rock due to waves – different to weathering
which only “breaks it down” on the spot, erosion takes it away, too
The main processes of erosion are:
(1) Hydraulic power
• This is the sheer energy and power of the waves as they crash against rock,
compressing the air in the cracks and pressurising the rock
(2) Abrasion
• Small rocks carried in the water scrape against rock, creating a sandpapering
effect
(3) Attrition
• Rocks carried by the sea will collide and break into smaller pieces, causing them
to become more rounded
(4) Solution – NOTE: this is not on spec, so use it carefully
• When the sea is slightly acidic so dissolves certain chemicals within it
, TJNOTES
Transportation by Longshore Drift
• Material can be transported along the coast
via longshore drift
• This is when prevailing winds cause waves to
hit the coast at an angle
• The swash is therefore at an angle, carrying
material up the beach in the same direction as the
waves
• The backwash carries material down the
beach at right angles back into the sea
• Over time, material zigzags along the coast line and the material moves along the
coast
Deposition
• Deposition is the dropping of material
• It occurs when water that is carrying sediment loses energy and slows down
• Coasts build up when amount of deposition is greater than the amount of
erosion, this is often the case with constructive waves because the drop more
material than they remove – hence deposition takes place
• This often occurs in sheltered bays and where water is protected by spits and
bars because waves lose energy at headlands and energy is absorbed by the spit
or bar
• Amount of material deposited is increased when there is erosion elsewhere on
the coast because lots of material is being transported in the sea
Erosional Landforms
Headlands and Bays
• The coastline is discordant where there are regular, alternating bands of hard
rock (like granite) and soft rock (like clay) are found at right angles to the coast
• The soft rock erodes faster by abrasion and hydraulic power than the hard rock,
so this part of the coastline recedes faster, forming a bay
• Because the hard rock is more resistant to erosion, it forms a headland which is
an area sticking out of the coastline
[note: on the spec, it says how geological structure and rock types influence coastal
forms, you would simply talk about concordant and discordant coastlines and their
relationships to headlands and bays]
AQA GCSE Geography Paper 1 notes,
Section C : Physical landscapes in the UK
PAPER, I
SECTION C
Waves
• As wind blows over the surface of the sea, waves are formed
• The greater the fetch (distance travelled), the more powerful (higher energy) the
wave
There are two types of waves:
(1) Constructive
• These waves deposit material because they have a low frequency and are low in
energy
• Because they have a strong swash (water moving up the beach) and a weak
backwash (water moving down the beach), material is deposited
• Constructive waves are low in energy, have a low height and have a low
frequency
• They are formed in calm conditions and low wind speeds
(2) Destructive
• These waves erode the coast because they have a weak swash and a strong
backwash, causing sediment to be removed
• They have a high frequency, are high in energy and they are tall
• They are formed in stormy conditions and high wind speeds
Weathering
• Rock can be broken down by mechanical and chemical weathering
• The definition of weathering is: the breaking down of rock
• Mechanical weathering breaks down rock without changing its chemical
composition and the main mechanical weathering that takes place is freeze-thaw
weathering which takes place in the process:
• (1) Water enters the cracks in a rock
• (2) Water freezes and expands, putting pressure on the rock
• (3) When it thaws, it contracts, releasing pressure on the rock and, as this
process repeats, the freezing and thawing widens the crack and causes the rock
to break up
• Chemical weathering is the breakdown of rock by changing its chemical
composition
,TJNOTES
• Carbonation is a type of chemical weathering that takes place in warm and wet
conditions as carbon dioxide dissolved in rainwater makes it a weak carbonic
acid
• As the carbonic acid then reacts with rock that contains calcium carbonate
(limestone), rocks are dissolved by the rainwater and are broken down
Mass Movement
• Mass movement is when material, mud and rock fall down a slope due to the
force of gravity acting on the rock
• Mass movement causes the coast to retreat rapidly and it is more likely to take
place when material is full of water because water acts as a lubricant and makes
the material heavier
There are 3 processes of mass movement:
(1) Sliding
• This is when mud and blocks of rock shift and slide in a straight line along a slide
plane
(2) Slumping
• When material (usually saturated soil and weak rock) rotates along a curved slip
plane
(3) Rockfalls
• Material breaks up, often along bedding planes and falls down the slope as
crumbled rock
Processes of erosion
• Erosion is the WEARING DOWN of rock due to waves – different to weathering
which only “breaks it down” on the spot, erosion takes it away, too
The main processes of erosion are:
(1) Hydraulic power
• This is the sheer energy and power of the waves as they crash against rock,
compressing the air in the cracks and pressurising the rock
(2) Abrasion
• Small rocks carried in the water scrape against rock, creating a sandpapering
effect
(3) Attrition
• Rocks carried by the sea will collide and break into smaller pieces, causing them
to become more rounded
(4) Solution – NOTE: this is not on spec, so use it carefully
• When the sea is slightly acidic so dissolves certain chemicals within it
, TJNOTES
Transportation by Longshore Drift
• Material can be transported along the coast
via longshore drift
• This is when prevailing winds cause waves to
hit the coast at an angle
• The swash is therefore at an angle, carrying
material up the beach in the same direction as the
waves
• The backwash carries material down the
beach at right angles back into the sea
• Over time, material zigzags along the coast line and the material moves along the
coast
Deposition
• Deposition is the dropping of material
• It occurs when water that is carrying sediment loses energy and slows down
• Coasts build up when amount of deposition is greater than the amount of
erosion, this is often the case with constructive waves because the drop more
material than they remove – hence deposition takes place
• This often occurs in sheltered bays and where water is protected by spits and
bars because waves lose energy at headlands and energy is absorbed by the spit
or bar
• Amount of material deposited is increased when there is erosion elsewhere on
the coast because lots of material is being transported in the sea
Erosional Landforms
Headlands and Bays
• The coastline is discordant where there are regular, alternating bands of hard
rock (like granite) and soft rock (like clay) are found at right angles to the coast
• The soft rock erodes faster by abrasion and hydraulic power than the hard rock,
so this part of the coastline recedes faster, forming a bay
• Because the hard rock is more resistant to erosion, it forms a headland which is
an area sticking out of the coastline
[note: on the spec, it says how geological structure and rock types influence coastal
forms, you would simply talk about concordant and discordant coastlines and their
relationships to headlands and bays]
