Coastal zone

HideShow resource information
  • Created by: C.P.
  • Created on: 06-04-13 18:16
View mindmap
  • COASTAL ZONE
    • LANDFORMS RESULTING FROM EROSION
      • FLAMBOROUGH HEAD
        • 1.Caves arches stacks and stumps form as a resultof erosion.
        • 2.Headlans form where there is less resistant rock and there tends to be faults in the resulting headland.
        • 3.Waves expose these weakness. There are 3 ways it does this.
          • 1. HYDRAULIC ACTION (force of the waves themselves)
          • 2. CORRASION (material flung against the cliff)
          • 3.CORROSION (dissolving of the rock)
          • 4.The continued erosion leads to a cave.
        • 5. If the wave forms part of a narrow headland, the continued erosion may lead to the other side getting broken through causing an arch to form.
          • E.G. Durdle Door.
        • 6.Continued erosion will lead to the base being too wide and the roof of the arch will collapse.
        • 7.When the roof collapses it will leave a stack.
          • E.G. Old Harry
        • 8. Eventually, the base of the stack will be undercut and a stump will form.
          • E.G.Old harrys wife
    • LANDFORMS RESULTING FROM DEPOSTION
      • SPURN POINT
        • 1. Eroded materials are transported along the coast by longshore drift
          • LONGSHORE DRIFT
            • 1. Longshore drift is when sand and pebbles are moved along a coastline by the sea
            • 2. The material follows a zig-zag course.
            • 3.The direction in which the materials travel is goverened by the previaling wind.
            • 4.Groyned are built to stop long shore drift from hapening.
        • 2.Where there is a bend in the coastline deoposition will occur.
        • 3.The material builds up and forms a spit
          • 4.Some spits extend part way across Estuaries
            • E.G. Spurn Point
            • 5.They cannot grow totally across because the river current is to strong.
        • 6.When winds blow from a different direction it causes the spit to become curved.
        • 7. When the wind goes back to its normal direction the spit extends again.
        • 8.Salt marshes devolop behing the spit. here, mud is deposited making the water shallower.
        • 9.Spits become permanent when sand is blown on tothem causing sand dunes and locking them in place.
    • IMPACT OF COASTAL FLOODING
      • EAST ANGLIA
        • POLITICAL
          • In 30 years time the Thames Barrier will have to be replaced.
        • ENVIROMENTAL
          • 20% of salt marshes will be lost by 2050 due to rising sea levels
          • Low lying parts will become flooded
        • SOCIAL
          • Thames barrier being constructed -£80billion
          • 1953 300 dead in East Anglia.
        • ECONOMIC
          • Destroying agriculture-The Fens
          • Jobs will be lost in cities and other areas.
      • MALDIVES
        • SOCIAL
          • Houses are damaged and destroyed
          • Limited acces to freshwater means that if floods occur then the freshwater available will drop.
        • POLITICAL
          • Maldivian goverment ask Japan for $60million to build sea walls.
          • They became carbon neutral.
          • Buying land in Austrailia and India so they can move people when the islands become uninhabitable.
        • ECONOMIC
          • Loss of tourism. The Maldives has only one airport and if that becomes flooded then there will be no tourists.
          • Disrupted fishing industry. Damageing fish processing plants will ruin their economy as fish is their biggest export.
        • ENVIROMENTAL
          • Loss of beaches will casue further land to flood as there is less of a buffer.
          • Loss of soil as the soil is thin and floods can easily destroy it.
    • COAST EROSION- MAPPLETON ON HOLDERNESS COAST
      • Cliff is constantly retreating due to erosion
      • About 1.8m of land lost every year.
      • WHY ITS ERODING QUICKLY.
        • Easily eroded rock type
        • Narrow beaches- less protection from waves.
        • Groynes were built which stops sand being devoloped and this leads to less protection
        • Powerful waves causes massive damage as they have a big fetch.
      • IMPACTS ON PEOPLE
        • Homes near cliffs are at risk of collapsing which means home insurance is impossible to get.
        • Property prices have fallen
        • Easlingtons Gas Terminal is 15m from cliff- 25% of britains gas.
        • Roads have collapsed into the sea.
      • IMPACTS ON ENVIROMENT
        • Some sites of special scientific intrest sre threatened
          • Lagoons near Easington may be destroyed as they are sepearated from the sea by a narrow bar, if the bar is eroded the lagoons will be destroyed.
    • COASTAL MANAGEMENT- HOLDERNESS COAST.
      • HARD
        • SEA WALL
          • ADS
            • Prevents erosion on the coast and acts like a barrier
          • DIS-ADS
            • Creates a strong back wash which erodes underneath
              • Expensive.
          • A wall that deflects waves
        • ROCK ARMOUR
          • DIS-ADS
            • Need to be replaced frequently
          • ADS
            • Absorb the wave energy
              • Fairly cheap
          • Large boulders that are built along the coast.
        • GROYNES
          • DIS-ADS
            • Down the coast there is less sand deposited so there is less of a buffer from the sea for them- more damage.
          • ADS
            • Bigger beach-more absorbsion
              • Fairly cheap
          • Wooden or stone fences that build up sand making beaches wider.
      • SOFT
        • MANAGED RETREAT
          • Removing a sea defence and letting the land behind flood on purpose-creating marshland.
            • ADS
              • Cheap
                • Marshland stops flooding
            • DIS-ADS
              • People disagree on what land to flood
        • BEACH NOURISHMENT
          • When sand and shingles that are added to the beach from the sea.
            • ADS
              • Bigger beach- more protection
            • DIS-ADS
              • Exspensive
                • Frequently managed
        • SAND DUNES
          • Adding sand and creating sand dunes
            • ADS
              • Effective barrier
            • DIS-ADS
              • Exspensive
                • Protection area is limited
    • KEY HAVEN MARSHES
      • THE RESULTING HABITAT
        • Due to rising sea levels (6mm) per year - the salt marsh retreats 6m a year under the water.
        • Major storms mean the marsh is also under threat.
          • 1989 a storm did just this and the open area was retreated in less than three months.
        • The sea wall could break as a result and ruin the salt marsh.
        • Tourism also effects the area badly.
      • ENVIROMENTAL FEATURES
        • Lots of wildlife
        • Cordgrass
        • Sea lavender plant-attracts wildlife
        • Oystercathcer a bird
        • It is beetween a sea wall and the sea
      • WHATS BEING DONE TO PROTECT IT
        • The sea walls were thickened and hightened- £5million.
        • Tourism restricted
        • Turned into SSSI- meaning that no devolopment and limited access.
        • Nothing can be done about sea level.

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Coastal zones resources »