Coastal landforms

• Wave reaching the shore

  1. Wave begins to break

  2. Circular motion in Open Water

  3. Friction with seabed distorts motion

  4. Motion becomes elliptical in shape

  5. Swash runs at the beach

  6. Backwash runs back down the beach
• Characteristics of constructive waves

  • Long wavelength
  • Low wave height
  • Strong swash
  • Build up the beach
  • Carry in sand and pebbles
• Characteristics of destructive waves

  • Short wavelength
  • Wave height over 1 meter
  • Strong backwash
  • Remove sand and pebbles from the beach
  • Cause damage
• Coastal landforms created by erosion


  • Headlands
  • Arches
  • Wave cut platforms
  • Stacks
• Coastal landforms created by deposition


  • Spits
  • Beaches
  • Bars
  • Sand Dunes
• Formation of a stack

  1. Headland has a crack

  2. Abrasion and hydraulic action enlarges crack into a cave

  3. Wave erosion deepens cave until it cuts through headland forming an arch

  4. Roof of arch weathers and collapses

  5. Stack is left behind

  6. Stack is eroded to form a stump
• Bays and headlands form where there are alternating bands of more and less resistant rock along a coastline
• The less resistant rock erodes more rapidly to form bays, the more resistant rock erodes less rapidly to form headlands
• Over time, refraction means the wave energy becomes concentrated on the headland, increasing the rate of erosion
• Formation of a wave cut platform

  1. Waves erode cliff through hydraulic action and abrasion

  2. Part of cliff reached by waves is eroded to form a wave cut notch

  3. Rocks above notch collapse

  4. Cliff retreats back

  5. Base of cliff left behind is the wave cut platform
• Chemical weathering


  Weakening and breaking up of rocks in their original place, e.g. by acid rain
• Slumping


  A form of mass movement where waterlogged cliffs, often clay, slide downwards
• Geological structure


  The different types of rocks found in a coastline, whether they are discordant or concordant, which impacts erosion and landforms
• Deposition


  The process where sediment is laid down by water, wind or ice
• Cliff collapse is an image showing parts of a cliff disappearing, with bare areas, vegetation, and weathering of the sandstone cliff
• Mass movement


  Downward movement of material because of gravity
• Types of mass movement

  • Slumping
  • Rockfall
  • Landslide
• Landslide


  A block of rock sliding down a cliff
• The image shows a cliff collapse
• The cliff is made of sandstone and there is weathering taking place
• Something has been put in place to keep people away from the cliff edge and stabilize it
• Recurved sea wall


  Designed to stop flooding and reflect waves back onto the beach
• Groin


  Designed to stop the effects of longshore drift and hold sand in place
• Rock armor


  Large boulders placed at the bottom of a sea wall or cliff to dissipate wave energy
• Dune stabilization


  Stabilizing sand dunes to act as a natural barrier to the sea
• Beach nourishment


  Adding beach materials like sand or pebbles to build up the beach and decrease erosion
• Hard coastal engineering is controversial as many old defences are falling into disrepair and not being replaced
• Advantages of hard coastal engineering

  • Provide a barrier to coastal erosion or flooding
  • People feel safer
• Disadvantages of hard coastal engineering

  • Damage to coastal habitats
  • Changes to erosion and transportation affect other parts of the coastline
  • Extremely expensive
• The three topics covered are: Landforms, Coastal Management, and Processes