Deposition

• What is Deposition?

  Dropping of material carried by water
• When does Deposition occur?

  When water slows down and can't carry sediment
• How are coasts built up?

  When deposition exceeds erosion
• What increases deposition on a coast?

  High erosion elsewhere and transportation of material
• What characterizes low energy waves?

  They carry material but don't erode much
• What are constructive waves?

  Waves that deposit more material than they erode
• What is the frequency of constructive waves?

  6-8 waves per minute
• Describe the characteristics of constructive waves.

  They are low, long, and have powerful swash
• What happens during the swash of constructive waves?

  It carries material up the coast
• What is the effect of the backwash in constructive waves?

  It is weaker and doesn't take much material back
• What is a spit?

  A landform that extends from the coastline
• How do spits form?

  At coastlines where longshore currents exist
• What is a bar in coastal geography?

  A landform that joins two land areas
• What are beaches formed by?

  Deposition of materials like sand and shingle
• Where are beaches located?

  Between the high and low water marks
• What are the characteristics of sand beaches?

  Flat, wide, with gentle slopes
• What are the characteristics of shingle beaches?

  Steep, narrow, with large particles
• What processes lead to the formation of spits, bars, and sand dunes?

  • Spits form from longshore currents depositing material
  • Bars join two land areas through sediment accumulation
  • Sand dunes form from wind-blown sand accumulation
• What are the differences between sand and shingle beaches?

  • Sand beaches:
  • Flat and wide
  • Small particles
  • Weak backwash creates gentle slope
  • Shingle beaches:
  • Steep and narrow
  • Large particles
  • Weak backwash can't move them back down