Coasts

• the littoral zone is the coastal area affected by waves
• 5 parts of littoral zone are the coast, backshore, foreshore, nearshore and offshore
• 3 features of high energy coasts?

  large, powerful and destructive waves

  strong winds and long fetches

  cliffs with high erosion, steep and little vegetation
• 3 features of a low energy coastline?

  small, gentle constructive waves

  gentle winds, short fetches and sheltered

  low elevation - high deposition
• 3 features of destructive waves are?

  strong backwash, weak swash

  short wavelength, high frequency

  high and steep
• 2 features of constructive waves?

  low frequency and long wavelength

  strong swash and weak backwash
• a short term change to waves is a storm event
• a long term change to waves is seasonal changes - summer constructive, winter destructive
• sediment cells are where movement of material is self contained
• there are 11 sediment cells in the UK
• 2 sources of sediment cells are erosion, weathering of a cliff face and rivers carrying eroded sediment from inland into coastal system'
• 2 transfers/flows of sediment cells are longshore drift and wind
• 2 sinks/stores of sediment are beaches and formation of spits and bars
• positive sediment budget is when more sediment enters an area than leaves it
• negative sediment budget is when more sediment leaves than enters an area
• the sediment cell case study is from Portland Bill to Selsey Bill
• a discordant coastline is when the rock strata runs perpendicular to the sea with alternating bands of hard and soft rock
• what landform can form at discordant coastlines?


  headland and bays
• headland and bays are formed by the less resistant rock eroding faster, forming a bay and more resistant rock eroding slower, forming a headland
• wave refraction is when waves approach a coastline at an angle and their direction changes with shape of coastline
• beaches can form on bays as the wave energy is dissipated, so sediment is dropped
• concordant coastlines are where rock strata runs parallel to the sea
• what landforms form at concordant coastlines?

  coves, dalmatian coastlines and haff coastlines
• at concordant coastlines, once the waves break the more resistant outer rock it exposes the less resistant rock behind it, softer rock erodes at a faster rate until it reaches the next harder rock forming a cove
• dalmatian coastlines are formed by a rise in sea level where valleys are parallel to the coast
• a country that has a dalmatian coastline?

  Croatia
• the Baltic Sea is an example of a Haff Coastline
• haff coastlines are where deposits of sand lie on top of offshore bars which can form lagoons
• faults are more susceptible to erosion because they allow water to run between strata
• dip is the angle the rock strata faces the sea
• 4 geological structures at coasts are faults, dips, joints and folds
• 3 things the profile of a cliff depend on?

  resistance of rock

  energy of coastline

  position of rock strata
• if strata dips horizontally, cliff is unstable because weaker soft rock eroded causing notches
• if strata dips away from sea, cliff is stable as there's no undercutting
• if strata dips towards sea, more resistant rock is undercut - causing mass movement
• if strata is steep, it causes large slabs of rock to slide down cliff face
• micro features are small scale features caused by erosion or weathering like caves
• what is the case study for geological structures and landscape?

  Glamorgan Heritage Coast
• 5 things about Glamorgan Heritage Coast?


  high energy coastline in south of Wales

  Bristol Channel provides destructive waves which causes discordant coastline prone to cliff falls

  headlands are at Witches Point

  bays at Dunraven

  wave cut platform at Nash point
• 2 things coastal recession depends on?

  bedrock lithology and lithological structure