The Coastal Zone
Coastal Zone: Wind, wave, tides and movement of material are all part of the coastal zone and this can occur
onshore or offshore. Humans have a huge impact in coastal zones and are heavily reliant on it.
The Coastal System
Coastal System: The development of a coastal landscape over time can be viewed within a systems framework. A
system is a set of interrelated objects compromising components (stores) and processes (links) that are connected
together to form a working unit or unified whole. Coastal landscape systems store and transfer energy and material
on timescales that can vary from a few days to millennia.
Why is the Coastline of the British Isles so Uneven?
⮚ Lithology Marine Processes
⮚ Geology Sea Level Change
⮚ Sub-aerial processes Rivers
Types of Coastline
Sandy Coastlines: Formed on low-energy coastlines where constructive waves deposit material due to strong
swash.
Rocky Coastlines: Where high-energy waves prevent the build up of material. Weak geology is removed leaving
resistant geology to form cliffs.
Estuarine Coast: Formed by rivers meeting the coast. Carried sediment is dropped forming deltas. Flocculation
often occurs creating mud flats in sheltered areas.
Energy Within the Coastal System
In coastal systems, energy can be transferred from neighbouring systems, which could (for example) be river
systems or other coastal systems. These are therefore INPUTS.
This can then be transferred to other neighbouring systems as an OUTPUT.
A good example of this is the input of fluvial sediment from a river, as it deposits its load at the mouth when energy
decreases, it is then stored until erosion or longshore drift carry the sediment out of the system.
Types of Energy Involved
Kinetic – the energy of motion & movement.
Potential – the energy possessed by something to be released.
Thermal – linked to kinetic energy, motion within particles.
It is this energy that enables work to be carried out by the natural processes that shape the landscape.
, The Littoral Zone
Backshore: This is the area between the high-
water mark and the landward limit of
marine activity.
Foreshore: This is the area lying between the
high-water mark and the low water mark
and is often seen as the most important area
for marine activity.
Inshore (Nearshore): The area between the
low water mark and the point where the
waves cease to have any influence on the
land around them.
Offshore: The area beyond the point where
waves cease to impact the seabed and in
which activity is limited to the deposition of
sediments.
The Coastal System
• Within the coastal zone, energy and material are circulated within a system which shapes the coasts.
• The coast is an open system – i.e. free movement of energy and matter in and out of the system.
INPUTS: Wind – transfers energy in the form of waves.
Rain – attacks cliffs.
Rock Type – hard rock / soft rock.
Rock Structure
Sediment – shingle; sand and mud.
PROCESSES: Erosion: Erosional Landforms:
Corrasion Cliffs
Corrosion Wave-cut platforms / notches
Hydraulic action Headlands and bays
Attrition Caves, arches, stacks, stumps
Transportation:
● The transfer of energy and material by longshore drift.
Deposition:
● Material deposited due to loss of energy (e.g. in sheltered bays / shallow water)
● Landforms: beaches, spits, bars, tombolos
OUTPUTS:
❖ Material carried out to sea.
❖ Material deposited above the high tide mark.
Coastal Zone: Wind, wave, tides and movement of material are all part of the coastal zone and this can occur
onshore or offshore. Humans have a huge impact in coastal zones and are heavily reliant on it.
The Coastal System
Coastal System: The development of a coastal landscape over time can be viewed within a systems framework. A
system is a set of interrelated objects compromising components (stores) and processes (links) that are connected
together to form a working unit or unified whole. Coastal landscape systems store and transfer energy and material
on timescales that can vary from a few days to millennia.
Why is the Coastline of the British Isles so Uneven?
⮚ Lithology Marine Processes
⮚ Geology Sea Level Change
⮚ Sub-aerial processes Rivers
Types of Coastline
Sandy Coastlines: Formed on low-energy coastlines where constructive waves deposit material due to strong
swash.
Rocky Coastlines: Where high-energy waves prevent the build up of material. Weak geology is removed leaving
resistant geology to form cliffs.
Estuarine Coast: Formed by rivers meeting the coast. Carried sediment is dropped forming deltas. Flocculation
often occurs creating mud flats in sheltered areas.
Energy Within the Coastal System
In coastal systems, energy can be transferred from neighbouring systems, which could (for example) be river
systems or other coastal systems. These are therefore INPUTS.
This can then be transferred to other neighbouring systems as an OUTPUT.
A good example of this is the input of fluvial sediment from a river, as it deposits its load at the mouth when energy
decreases, it is then stored until erosion or longshore drift carry the sediment out of the system.
Types of Energy Involved
Kinetic – the energy of motion & movement.
Potential – the energy possessed by something to be released.
Thermal – linked to kinetic energy, motion within particles.
It is this energy that enables work to be carried out by the natural processes that shape the landscape.
, The Littoral Zone
Backshore: This is the area between the high-
water mark and the landward limit of
marine activity.
Foreshore: This is the area lying between the
high-water mark and the low water mark
and is often seen as the most important area
for marine activity.
Inshore (Nearshore): The area between the
low water mark and the point where the
waves cease to have any influence on the
land around them.
Offshore: The area beyond the point where
waves cease to impact the seabed and in
which activity is limited to the deposition of
sediments.
The Coastal System
• Within the coastal zone, energy and material are circulated within a system which shapes the coasts.
• The coast is an open system – i.e. free movement of energy and matter in and out of the system.
INPUTS: Wind – transfers energy in the form of waves.
Rain – attacks cliffs.
Rock Type – hard rock / soft rock.
Rock Structure
Sediment – shingle; sand and mud.
PROCESSES: Erosion: Erosional Landforms:
Corrasion Cliffs
Corrosion Wave-cut platforms / notches
Hydraulic action Headlands and bays
Attrition Caves, arches, stacks, stumps
Transportation:
● The transfer of energy and material by longshore drift.
Deposition:
● Material deposited due to loss of energy (e.g. in sheltered bays / shallow water)
● Landforms: beaches, spits, bars, tombolos
OUTPUTS:
❖ Material carried out to sea.
❖ Material deposited above the high tide mark.
