Geography- Physical Landscapes

• Formation of coastal spits- deposition

  1. swash meet at the beach at the angle of the prevailing wind
  2. backwash move down the beach at 90° to the coastline, due to gravity
  3. zigzag movement (longshore drift) transports material along the beach
  4. The deposition causes beach to extend until reaching a river estuary
  5. change in prevailing wind direction forms a hook
  6. sheltered area behind spit encourages deposition, Salt marsh forms
• How do waves forms?


  Waves are created by winds blowing over the surface of the sea, friction is created- producing a swell in the water.
• how do waves break?

  1. Waves start out at sea
  2. As waves approaches the shore, friction slows the base.
  3. This causes the orbit to become elliptical
  4. until the top of the wave breaks over
• types of erosion

  • Attrition
  • Solution
  • Abrasion
  • Hydraulic action
• Attrition

  rocks that bash together to become smooth/smaller
• Solution

  A chemical reaction that dissolves rocks
• Abrasion

  rocks hurled at the base of a cliff to break pieces apart
• Hydraulic action

  water enters cracks in the cliff, air compresses, causing the crack to expand
• Types of weathering

  weathering is the breakdown of rocks where they are.

  • carbonation
  • mechanical
• carbonation

  Breakdown of rock by changing its chemical composition
• mechanical weathering

  Breakdown of rocks without changing its chemical composition
• What is deposition?

  When the sea or river loses energy, it drops the sand, rock particles and pebbles it has been varying. This is called deposition.
• types of transportation

  A natural process by which eroded material is carried/transported.

  • solution
  • suspension
  • saltation
  • Traction
• Solution


  Minerals dissolve in water and are carried along
• suspension 


  sediment is carried along in the flow of the water
• Saltation


  Pebbles that bounce along the sea/river bed
• Traction 


  Boulders that roll along a river/sea bed by the force of the flowing water
• Mass Movement

  1. Rain saturates the permeable rock above the impermeable rock making it heavy
  2. Waves or a river will erode the base of the slope making it unstable
  3. Eventually the weight of the permeable rock above the impermeable rock weakens and collapses.
  4. The debris at the base of the cliff is then removed and transported by waves or river
• formation of headlands and bays

  1. Waves attack the coastline
  2. softer rock is eroded by the sea quicker forming a bay, calm area cases deposition
  3. More resistant rock is left jutting out into the sea. This is a headland and is now more vulnerable to erosion
• Formation of a coastal stack

  1. Hydraulic action widens the cracks in the cliff face over time
  2. Abrasion forms a wave cut notch
  3. Further abrasion widens the wave cut notch to form a cave
  4. caves from both sides of the headland break through to form an arch
  5. weather above/erosion below- arch collapses leaving a stack
  6. Further weathering and erosion leaves a stump
• Freeze-Thaw weathering

  Stage 1: water seeps into cracks and fractures in the rock

  Stage 2: When the water freezes, it expands about 9%. This wedges apart the rock

  Stage 3: with repeated freeze-thaw cycles, the rock breaks off
• Types of waves

  Constructive, Destructive
• Constructive waves

  This wave has a swash that is stronger than the backwash. This therefore builds up the coast.
• Destructive waves


  This wave has a backwash that is stronger than the swash. This therefore erodes the coast.
• Size of waves

  • Fetch how far the wave has travelled
  • strength of the wind
  • how long the wind has been blowing for
• Coastal defences

  Hard engineering

  • groynes
  • sea walls
  • gabions
• Coastal defences- soft engineering

  • beach nourishment
  • managed retreat