Section C: Physical landscapes in the UK

What is erosion?

What are the 4 types?

* The wearing away and removal of material
* Hydraulic action, abrasion, attrition and solution.

What is weathering?

The breaking down of rocks in situ

What is deposition?

Where does deposition usually occur on a beach?

Where does deposition usually occur in a river?

* The dropping of material due to loss of energy
* Deposition usually happens in the bays of a headland because when headlands and bays form, over time, the amount of energy will be focussed more on the headlands, resulting in less energy hitting the bays so deposition will happen here.

What is transportation?

What are the 5 types?

* The movement of eroded material
* Traction, saltation, suspension, solution and longshore drift

Name 5 coastal processes

* weathering processes – mechanical, chemical
* mass movement – sliding, slumping and rock falls
* erosion – hydraulic power, abrasion and attrition
* transportation – longshore drift
* deposition – why sediment is deposited in coastal areas.

How do waves form?

When wind blows over water

What is fetch?

How does fetch affect teh wave?

The distance the wind blows across the water/ the distance the wave has travelled.

The bigger the fetch, the bigger the wave

Define swash

The movement of water up the beach

Define backwash

The movement of water backdown the beach

What are the two types of waves?

* Constructive waves (builds up beaches/coastline)
* Destructive waves (erodes coastlines)

Name 6 characteristics of constructive waves

* Wave height - low
* Wave length - long
* Type of wave break - long and low
* Strength of swash - strong (powerful)
* Strength of backwash - weak
* Net beach sediment - Gain

Name 6 characteristics of destructive waves

* Wave height - high
* Wave length - short (steep)
* Type of wave break - high and steep
* Strength of swash - weak
* Strength of backwash - powerful
* Net beach sediment - Lose

What are the two types of weathering?

* Mechanical weathering (physical)
* Chemical weathering
* Potentially freeze-thaw weathering but falls under physical

What is mechanical weathering?

* Mechanical (physical) weathering is the disintegration of rocks through physical processes such as freeze-thaw weathering. Where this happens, piles of rock fragments called scree can be found at the foot of cliffs.

Explain freeze-thaw weathering

* Water collects in cracks or holes (pores) in the rock
* At night, this water freezes and expands and makes cracks in the water bigger
* When the temperature rises and the ice thaws, water will seep deeper into the rock
* After repeated freezing and thawing, fragments of rock may break off and fall to the foot of the cliff (scree)

What is chemical weathering and give an example?

* Chemical weathering involves a chemical reaction (effectively caused by chemical changes). Rainwater, which is slightly acidic, very slowly dissolves certain types of rocks and minerals such as alkaline rocks like limestone.

What is mass movement?

What are the three types of mass movement?

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* Mass movement - surface materials move down a slope **under the influence of gravity.** When mass movement occurs along coastlines, this material is often transported further along the coast by the process of longshore drift.
* The three types of mass movement are:
* Sliding
* Slumping
* Rock falls

What is sliding (mass movement)?

* This is the sudden movement of large volumes of rock and soil along a zone of saturated soil

What is slumping (mass movement)?

* This is the rapid mass movement of permeable rock and soil such as clay, which has become heavily saturated, lying on top of impermeable rock

What is rock falls (mass movement)?

* This is the free-fall movement of rock fragments due to gravity. This process is often increased by mechanical weathering such as freeze-thaw weathering.

What is hydraulic action (erosion)?

* The sheer power of the waves as they smash against the cliff. Air becomes trapped in the cracks in the rock and causes the rock to break apart.

What is abrasion (erosion)?

* This is when pebbles grind along a rock platform, much like sandpaper. Overtime, the rock becomes more smooth.

What is attrition (erosion)?

* This is when rocks that the sea is carrying knock against each other. They break apart to become smaller and more rounded, smoother aswell.

What is solution (erosion)?

* This is when sea water dissolves certain types of rocks. In the UK, chalk and limestone cliffs are prone to this type of erosion.

What is traction (transportation)?

* Where pebbles and larger material are **rolled** along the sea bed.

What is saltation (transportation)?

* Where small pieces of shingle or large sand grains are **bounced** along the sea bed.

What is suspension (transportation)?

* Small particles such as silts and claus are **suspended** in the **flow** of water.

What is solution (transportation)?

* When minerals in rocks like chalk and limestone are **dissolved** in sea water and then carried in solution. The load is not visible.

What is longshore drift?

Explain how it works

* Longshore drift - the movement of sediment along the beach
* The **prevailing wind** blows waves carrying sediment into the beach at an **angle** to the coast. **Swash** moves the sediment up the beach and the **backwash** drags it back down at a **90-degree** angle under the influence of **gravity**. This results in a **zigzag** motion as **sediment is transported** along the **coastline**.

What two ways can geology affect coastal landscapes?

* Rock type - rocks vary on their strength and resistance to erosion
* Geological Structure - this is to be the arrangement of rocks

What is a discordant coastline made up of?

* Alternating layers of hard and soft rock

Name 3 landforms resulting from erosion

* Headlands and bays
* Wave cut platforms
* Caves, arches, stacks and stumps

Name 4 landforms resulting from deposition

* Beaches
* Sand dunes
* Spits \[longshore drift\]
* Bars

What is the formation of headlands and bays? \[6\]

1. Because of differences in the resistance of rocks to erosion. some parts of the coast may retreat faster than others.
2. This will happen where the rocks are at right angles to the coastline (a discordant coast).
3. Over thousands of years, the softer rock will be eroded through the processes of hydraulic action and abrasion more quickly than the harder rock and differences become more pronounced.
4. Eventually, there will be headlands that stick out into the sea (more resistant rock) and bays where the land has been worn back.
5. The headlands are more exposed to wave attack and erosional landforms develop.
6. Due to wave refraction, the energy of the waves is then focussed on the headlands and less in the bays so beaches form here.

What is the formation of a wave-cut platform? \[7\]

==Name a characteristic==

1. Between high and low tide, rocks are hurled at the base of the cliff - called abrasion.
2. This creates a wave-cut notch, the cliff has been undercut.
3. The top of the cliff becomes unstable.
4. This overhang will collapse into the sea providing more material for abrasion.
5. The cliff has now retreated. The process of abrasion will continue,
6. Because there can be no erosion below low tide a rock platform is left - called a wave-cut platform - this is exposed at low tide.
7. ==A wave-cut platform is typically quite smooth due to the process of abrasion. However, in some places, it may be scarred.==

What is the formation of caves, arches, stacks and stumps? \[4\]

1. Firstly, the sea attacks the foot of the cliff and begins to erode areas of weakness such as joints and cracks, through processes of erosion such as hydraulic action and abrasion.
2. Gradually, the cracks get larger, developing into small caves. Further erosion, widens the cave and where the fault lines run through the headland, two caves will eventually erode into the back of each other forming an arch, passing right through the headland.
3. The combination of wave attack at the base of the arch, and weathering of the roof of the arch (frost, wind and rain) weakens the structure until eventually the roof the arch collapses inwards leaving a stack, a column of rock which stands separate from the rest of the headland.
4. The stack continues to erode, eventually collapsing to form a stump which may be covered by water at high tide.

What is a beach?

What are the two types of beaches?

Where are they found?

* Beaches are deposits of sand and shingle (pebbles) at the coast.


1. Sandy beaches - Sandy beaches form in sheltered bays when sand is deposited. The sheltered nature means the sand isn’t washed away. The waves entering the bay are constructive waves as they have a strong swash and build up the beach.
2. Pebble beaches - Pebble beaches can form on higher energy coastlines as it takes more energy to move pebbles than sand.