Erosion

• Erosion


  When material is broken down and moved away, wearing away of land.
• Weathering


  Breakdown or disintegration of rock in situ
• Erosion methods

  Corrasion/abrasion , attrition , solution/corrosion , hydraulic action and wave pounding(wave quarrying)
• Corrasion/abrasion


  When material (sand,pebbles) is hurled against cliffs, like a sandpaper effect

  Corrasion is more like hammering than sandpaper.
• Attrition


  Rocks, pebbles etc. hitting off each other which makes them smaller
• Solution/corrosion


  Weak acids in the seawater dissolve the alkaline rocks eg. Chalk and limestone
• Hydraulic action


  When a wave impacts a cliff face, air is forced into the cracks under high pressure, widening them and soon enough will break.
• Wave pounding / quarrying


  Destructive waves in storm conditions plunge heavy hydraulic pressure on a cliff can dislodge bits of rock. The wave scoops out loose unconsolidated material.
• What factors effect the rate of erosion?


  Geology (soft rock and hard rock), wave energy, sea defences, weathering and mass movement, geological structures
• formation of headlands and bays

  hard rock - erodes slower by hydraulic action soft rock - erodes faster by abrasion. formed only on a discordant coastline, sediment cells are between headlands.