Coastal landscapes

• What primarily causes most waves to form?

  The wind blowing across the sea
• How do waves increase in height as they approach the beach?

  Ripples created by wind pull the surface
• What are the two types of waves mentioned?

  • Constructive waves
  • Destructive waves
• What are the characteristics of constructive waves?

  • Strong swash, weak backwash
  • Low wave height, large wavelength
  • Low frequency
  • Depositional process

  
• What are the characteristics of destructive waves?

  • Strong backwash, weak swash
  • High wave height, small wavelength
  • High frequency
  • Erosional process

  
• What happens to material during the action of constructive waves?

  They deposit material on the beach
• What happens to material during the action of destructive waves?

  They erode the beach and take material away

  
• What factors affect the size of a wave?

  The strength of the wind, duration, depth, fetch
• What type of landforms do coastlines with constructive waves typically have?

  Depositional landforms like sandy beaches
• What type of landforms do coastlines with destructive waves typically have?

  Erosional landforms like rocky headlands
• What are the five coastal processes to know for the exam?

  • Erosion
  • Weathering
  • Transportation
  • Mass movement
  • Deposition

  
• What is erosion in the coastal context?

  The removal and destruction of rocks and sand

  
• What are the five types of erosion processes?

  1. Corrasion
  2. Abrasion
  3. Attrition
  4. Hydraulic Action
  5. Corrosion (Solution)

  
• How does corrasion contribute to erosion?

  Sand and pebbles are hurled against cliffs
• What is abrasion in the context of coastal erosion?

  Sediment scrapes against the base of rockfaces
• What occurs during attrition?

  Rocks and pebbles hit each other and wear down
• What is hydraulic action?

  Air is forced into cracks in rocks by waves
• How does corrosion (solution) affect coastal rocks?

  Mildly acidic seawater erodes alkaline rocks
• What landforms result from marine erosion on headlands?

  • Caves
  • Arches
  • Stacks
  • Stumps
• How does a cave form on a headland?

  Marine erosion widens cracks at the base
• What happens to an arch over time?

  It widens until it collapses into a stack
• What is a stack in coastal geography?

  A detached portion of an arch that remains
• What is a stump in coastal geography?

  A collapsed stack that remains as a small rock
• What type of rock is Old Harry Rocks made of?

  Chalk, which is a hard rock
• What type of rock is the Green Bridge of Wales made from?

  Sedimentary rock made from layers of sediment
• What is a wave-cut notch?

  An eroded notch created by marine erosion
• What happens as a wave-cut notch becomes deeper?

  The cliff face becomes unstable and collapses
• What is left behind after a cliff collapses due to a wave-cut notch?

  A wave-cut platform beneath the notch
• What is longshore drift?

  Sediment transported along the coast by waves
• What are the steps of longshore drift?

  1. Waves hit the beach at an angle
  2. Sediment is pushed up the beach in swash
  3. Gravity pulls sediment back down in backwash
  4. Sediment moves along the beach over time
• What occurs during deposition?

  Waves lose energy and drop sediment
• What are the characteristics of beaches?

  • Large deposits of sand and shingle
  • Formed by constructive waves
  • Typically have berms

  
• What is a spit?

  A long narrow strip of land formed by deposition
• How does a spit form?

  Waves lose energy and deposit sediment
• What happens when the prevailing wind changes direction regarding a spit?

  A hook may appear at the end of the spit
• What is a bar in coastal geography?

  A spit that grows across the mouth of a bay
• What does a bar create when it cuts off seawater from a bay?

  A lagoon with still water
• What are sand dunes?

  Accumulations of sand formed by prevailing winds
• What are the types of sand dunes based on their development?

  • Embryo dunes
  • Yellow dunes
• Where are embryo dunes found?

  In the upper beach area around obstacles