Headlands and Bays

• What is our example

  Dorset coastline The Jurassic coast

  
• what is the initial erosion (discordant coastline)

  The bands of soft rock erode more quickly than those of more resistant hard rock leaving a section of land jutting out into sea, called a headland

  
• Formation of a headland

  Discordant coastline

  - Along east coast of the Isle of Purbeck, alternating bands of hard (more resistant) and soft (less resistant) rock run at a right angles to the sea

  - The hard rock will be more resistant and therefore headlands ae created e.g Ballard point and Durlston Head
• Formation of a bay

  The areas where the soft rock has eroded away, next to the headland, are called bays

  - sheltered areas, wave erosion

  e.g Studland bay and swanage bay
• Impact of feedback


  positive feedback:

  differential erosion- change in shape of the coastline

  Negative feedback:

  More erosion at headlands and more deposition in bays can straighten the coastline= equilibrium
• What are the inputs of sediment and energy

  Wind and waves:

  Jurassic coast on south coast of UK, high energy coastland particularly when wind blows from south west

  Currents:

  Longshore drift carries sediment from west to east along this coastline