Coastal Processes and Terrain

1
Coastal Processes and Terrain
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Outline

• Impact of Waves and Currents
• Coastal Processes
• Coastal Landforms

3
Impact of Waves and Currents

• Currents are large volume of water moving
  horizontally
• Waves are undulations in the surface layer of
  water bodies
• Tides are rhythmatic oscillations causing
  fluctuations/bulges in sea level regularly
• Waves erode, currents deposit
• Landforms are made by waves

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Coastal Processes

• Coastline is interface of hydrospher,
  lithosphere, atmosphere
• Wind action very influential
• Tides, diastrophism, tectonics, continental Ice
  sheets may have influence

• Shore shaping forces are
• Changes in water level
• Tides
• Waves
• Currents
• Streamflow
• Ice push
• Organic secretions
• There is also chemical change

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Coastal sediment transport

• Beach Drifting Zigzag movement of sand by waves
• Costal deposition takes place in shoreline
• Estuary A finger of sea projecting inlands
• Ria Shoreline Coast with many estuaries

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Coastal Landforms

• Cliffs cliff built from erosion of headlands
• Benches Broad erosional platform
• Terraces submarine deposit of sand at the outer
  margin of a platform
• Barrier islands Long narrow sandbar
• Lagoons Body of quit salt water between mainland
  and barrier island
• Spits Linear deposit of marine sediments
• Fjord Coasts Glacial trough
• Coral coasts

• Beach Loose sediment and sand
• Backshore Upper part not reached by waves
• Berm Flat backshore beach deposited by waves
• Foreshore Between high and low tides
• Offshore Farther away from the shore

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Barrier Islands and Lagoons
Figure 20-17
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Spits
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Idealized Beach Profile
Figure 20-14
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Focus Waves

• Wind generated
• Crest, trough, wavelength, height
• Amplitude
• Swash
• Backwash
• Tsunami

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Waves
Figure 20-4
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Development of Waves
Figure 20-2
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Wave Refraction
Figure 20-5
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Normal High Tides
Figure 20-A(1)
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Spring and Neap Tides
Figure 20-A (2 and 3)