Geography

• Erosion


  The process by which the coastline gets worn away and moved elsewhere
• Erosion processes


  • Hydraulic action
  • Abrasion (comasion)
  • Attrition
  • Solution (corrosion)
• Hydraulic action


  The power of the wave forces water and air into cracks in the rock. This pressure forces fractures in rock to split apart. Over time, this creates faults and notches which get bigger
• Abrasion (comasion)


  The waves pick up rocks from the sea and throw them against the cliffs. Over time, this rubs and smooths the rock, like using sandpaper
• Attrition


  The sea picks up angular rocks and knocks them into each other. This chips away the corners to make them rounder
• Solution (corrosion)


  Salts or chemicals in the water act to dissolve the rocks they touch, for example limestone is dissolved by sea salt
• Coastal transport - longshore drift


  The process by which beach material is transported along the coast
• Coastal erosional landforms


  1. Large crack opened up by hydraulic action

  2. The crack grows into a cave by hydraulic action and abrasion

  3. The cave becomes larger

  4. The cave breaks through the headland forming a natural arch

  5. The arch is eroded and collapses

  6. This leaves a tall rock stack

  7. The stack is eroded forming a stump
• Coastal management


  • Hard engineering
  • Soft engineering
• Hard engineering


  Building structures to protect the coast; they tend to be expensive
• Soft engineering


  Working with nature by using natural materials or allowing nature to take back areas
• The Holderness coast stretches from Flamborough Head to Spurn Point in NE England. Much of Holderness consists of soft materials: clay with a mixture of boulders known as glacial till. Longshore drift transports beach material southwards, causing the beach to be smaller in some places
• Coastal features


  • Headland
  • Bay
  • Caves
  • Bars
  • Spits
  • Sand dunes
• Wave types


  • Constructive waves
  • Destructive waves
• Coastal processes


  • Erosion
  • Transport
  • Deposition
  • Weathering
• Hydraulic action


  • Water is forced into cracks
  • This forces the rock apart
• Attrition


  • Loose rocks carried by the sea knock into each other
  • They break down and become more smooth and smaller
• Solution/corrosion


  • Fragments of rock are picked up and hurled at the cliff by the sea
  • They scrape and gouge the rock
  • Chemical action of the sea water where minerals in the sea can dissolve rocks
• Four types of erosion


  • Hydraulic action
  • Attrition
  • Solution/corrosion
• Missing words: smaller, emeller
• Beach


  Coastal landform
• Sea


  Body of water
• Wide wave


  Large backwash
• Formation of Bays and Headlands

  1. Coastline faces wave attack with discordant bed of sediment

  2. Wave attack causes hydraulic action and attrition which causes the coast to retreat

  3. Less resistant rocks are eroded at a faster rate to create bays

  4. More resistant rocks stick out to sea as headlands

  5. During calm periods the sheltered bays allow deposition of beaches
• Resistant coastal geology


  • Sandstone
  • Chalk
• The coastline erodes at different rates depending on the resistance of the coastal geology
• Resistant rocks such as chalk and limestone erode slower forming Headlands
• Less resistant rocks erode faster forming bays
• Coastal landforms


  • Arch has collapsed to form a stack
  • Cave has been eroded to form an arch
• Creation of a Waterfall