Coastal landforms

• Headlands and bays form where there is a disconcordant coastline

  • this means that there are alternating bands of hard and soft rock along a coast
• Headlands and bays formation:

  1. Less resistant rock is eroded quickly
  2. This forms a bay
  3. Resistant rock is eroded slower, forming a headland
• headlands are eroded to form caves, arches, and stacks
• Headland erosion process

  1. They have weaknesses like cracks
  2. Waves crash into headlands and enlarge the cracks by hydraulic power and abrasion
  3. Cracks larger, forming a cave
  4. Erosion deepens the cave until it breaks through, forming an arch
  5. Erosion wears away the rock supporting the arch, until it collapses to form a stack
• Longshore drift is a process that moves material along coasts
• longshore drift

  1. waves follow direction of prevailing wind, hitting the coast at an angle
  2. the swash carries material up the beach
  3. the backwash carries material away from the beach at a right angle

  
• Spit formation

  1. Longshore drift transports sand past a bend in the coastline and deposits it in the sea
  2. The strong winds can curve the end of the spit
  3. The sheltered area behind is protected, and can become a mud flat or salt marsh