coast

• Mechanical

  definition:the breaking down or dissolving of rocks and minerals on the surface of the earth.

  1.Water collects in the crack in the rock

  2.Water freezes and expands,forcing the crack to widen

  3.Ice melts and water seeps deeper into the crack

  4.repeated freezing and thawing causing the rock to break
• Chemical

  -The weakening of the rock due to chemical reactions taken place.

  -Add rain can cause to dissolve
• Biological

  -The weakening of the rock through the burrowing of animals and the growing of plants.

  -Roots can break apart the rock
• Mass movement:

  Mass movement is when rocks loosened by weathering move down a slope under the influence of gravity.
• Landslide

  Large blocks of rock by weathering move down a slope
• Slumping:

  Saturated soil slumps down a curved surface
• Formation of a spit

  1. longshore drift moves sand along the beach in the direction of the prevailing wind.

  2. Coastline changes direction wind continues to blow

  3. Shallow and calm waters sand doesn't get washed away

  4. Beach grows until long spit grows into the sea

  5. A storm blows wind from the south to the east this cuts forming a hook

  6. A salt mash develops behind spit this happens because water has no energy to hold water
• Erosional processors:

  Hydraulic action- When the force of the water hits the cliff -pushes air in.

  Solution- When some type of rock are dissolved due to chemical reactions.

  Attrition- Material is carried and knocks into other pieces of material.

  Abrasion- Also known as the sandpaper effect -material carried in the sea hits the cliff and wears away at the cliff.
• Concordant vs discordant

  -Concordant coastline will only have one rock type

  -Discordant coastline will have different rock types
• Formation of a bar

  -a bar is a line of deposition that joins one piece of a mainland to another(usually a bay)

  -A spit is attached only at the end only at the one end.One end is in the sea.
• Geology & wave types

  -rock structures impact the rate of erosion and landforms are produced

  -Rocks that are all well jointed or many faults eroded quicker,waves attack these weakness
• Wave types

  Constructive:

  • Responsible for deposition and landforms such as beaches,bars and spits
  • Characteristics:strong swash,weak backwash
  • They break infrequently
  • long in relation to height
  • Found on gentle sloping beaches

  Destructive:

  • Responsible for erosion and landforms such as headlands,bays,caves,cliffs and wave cut platforms
  • Characteristics: strong backwash and weak swash
  • break frequently
  • tall waves
  • found on steep beaches
• Transportation processors

  Traction- heavy rocks and boulders are rolled along the sea bed

  saltation- small stones and pebbles are 'bounced' along the sea bed.This happens constantly as pebbles hit each other causing a chain reaction

  Suspension- Very small particles of sand or clay are 'suspended' in the water.They make the water look murky and will settle of time if the water stops moving.

  Solution- Takes place when material is dissolved in the water,it is invisible and doesn't colour the water.Occurs often in limestone landscapes where the water is very acidic.
• Why does deposition happen

  • Water loses energy needed to carry material
  • Water becomes too shallow to carry material
• Spits-A spit is an area of sand or shingle that extends out the sea.It caused by deposition.