Coastal Landscapes and Change – Physical Geography Notes Paper 1
The Coastal Zone
• Coast – The margin boundary where the land meets the sea.
Why do people live near a coast (dynamic environment)?
• Wide range of businesses and industries, e.g. ports, tourism etc.
• Physical conditions, e.g. tidal variation
Coastal system:
• Coasts are an open system
• They have inputs and output
Input à Processes à Outputs
Inputs:
• Marine – waves, tides, salt spray
• Atmosphere – sun, precipitation, air pressure, wind speed & direction, pollution,
recreation, settlement, defences
Processes:
• Erosion – hydraulic action, attrition, abrasion, solution
• Transportation – traction, saltation, suspension, LSD
• Deposition
• Succession
Outputs:
• Sands
• Beaches
• Sand dunes
• Spits
• Bars and Tombolos
• Headlands and bays
• Cliffs
• Wave cut notches
1
, • Wave cut platforms
• Caves
• Arches
• Stacks
• Stumps
The littoral zone:
• Part of a sea, lake or river that is close to the shore
• In coastal environments, the littoral zones extend from high water mark, which is rarely
inundated (flooded)
Zone generally divided into 3 zones:
1. The backshore – above high tide level, is only affected by waves during exceptionally high
tides and major storms
2. Near shore / off shore – permanently coverage of sea level
3. Foreshore – shallow waters close to the land. It extends from the spring high tide line, which
is rarely inundated, to the spring low tide, which is rarely not inundated
Classification of coasts (different physical features and processes):
• Wave energy
Ø Low energy sheltered coasts with limited fetch and low wind speeds resulting in
small waves
2
, Ø High energy exposed coasts, facing prevailing winds with long wave fetches,
resulting in powerful waves
• Formation processes
Ø Primary coasts are dominated by land based processes such as deposition at the
coast from rivers or new coastal landforms created by lava flow
Ø Secondary coasts are dominated by marine erosion or deposition processes
• Rock types
• Salinity of the water
• Coastal management
• Climate
• Tidal variation
Ø Tidal range varies hugely on coastlines, coasts can be microtidal, mesotidal or
macrotidal
• Prevailing wind
• Depth of the water (shallower offshore slower wave energy)
• Relief of the coast
• Sea level change
Ø Emergent coasts where the coasts are rising relative to sea level
Ø Submergent coasts are being flooded by the sea
• Sand dunes and saltmarsh
• Human intervention
3
, Coastal Geology
• The geology of the coastline will have a huge impact on the landscapes and features
that are formed
• Igneous – formed when molten rock cools and hardens, e.g. granite
Ø Characteristics – hard/resistant (particles tightly bonded)
• Sedimentary – made up of particles of other rocks and also dead organic matters that
have been compressed. Formed underwater. Made up of layers of rock that builds up
over time, e.g. limestone
• Metamorphic – made up of either sedimentary or igneous rocks that are exposed to
heat or pressure, e.g. marble (limestone)
Resistance, ‘hardness of a rock’:
This can be influence by a number of factors:
• The level of cohesion between the particles within the rock
• The minerals found with the rock and how susceptible they are in erosion
• The amount of weaknesses and cracks that are found within the rock
Structure:
4