Coastal Processes

• What are the two types of weathering?

  Mechanical and chemical
• What is weathering?

  Breakdown of rock in situ
• What is mechanical weathering?

  Breakdown of rock without chemical change
• What is chemical weathering?

  Breakdown of rock by changing its chemistry
• How does freeze-thaw weathering occur?

  Water freezes, expands, and contracts in cracks
• How does carbonation affect rocks?

  It dissolves rocks containing calcium carbonate
• What is mass movement?

  Shifting of rocks and loose material down a slope
• When does mass movement occur?

  When gravity exceeds supporting forces
• What are the three types of mass movement?

  Sliding, slumping, and rock fall
• How does sliding occur?

  Materials shift in a straight line
• What is slumping?

  Material rotates along a curved slip plane
• What is rock fall?

  Material breaks up and falls down a slope
• How are waves created?

  By wind blowing over the sea surface
• What are the two types of waves?

  Destructive and constructive
• What do destructive waves do?

  Erode the coast and destroy beaches
• What do constructive waves do?

  Deposit material and build beaches
• In destructive waves, which is more powerful?

  The backwash is more powerful than the swash
• In constructive waves, which is more powerful?

  The swash is more powerful than the backwash
• What are the key differences between destructive and constructive waves?

  • Destructive waves erode the coast
  • Constructive waves build up beaches
  • Destructive waves have stronger backwash
  • Constructive waves have stronger swash
• What are the learning objectives covered in this video?

  • Two types of weathering
  • Three types of mass movement
  • Destructive versus constructive waves
• What are the three types of erosion mentioned?

  Hydraulic power, abrasion, attrition
• What is hydraulic power in coastal erosion?

  Waves compress air in rock cracks
• How does abrasion contribute to erosion?

  Eroded particles scrape against the rock
• What occurs during attrition?

  Eroded particles collide and become rounded
• What is longshore drift?

  Movement of water along the coast
• How do waves follow the direction of the prevailing wind?

  Waves hit the coast at an angle
• What is the role of swash in longshore drift?

  Swash carries material up the beach
• What does backswash do in longshore drift?

  Backswash carries material back to the sea
• How does material move along the coast due to longshore drift?

  Material zigzags along the coast over time
• What are the four processes of transportation in coastal processes?

  • Traction: Large particles pushed along seabed
  • Saltation: Pebble-sized particles bounce along seabed
  • Suspension: Smaller particles carried in water
  • Solution: Soluble materials dissolve and are carried
• What is traction in coastal transportation?

  Large particles pushed along the seabed
• How does saltation occur?

  Pebble-sized particles bounce along the seabed
• What happens during suspension in coastal processes?

  Smaller particles are carried along in water
• What is solution in coastal transportation?

  Soluble materials dissolve and are carried
• When does deposition occur in coastal processes?

  When water loses energy and slows down
• What affects the rate of deposition?

  Rate of erosion and amount of transported material
• What happens to material during deposition?

  Material is let go by the water
• What is the definition of coastal processes?

  Processes affecting the coastline's shape and features
• Why is the diagram important for understanding longshore drift?

  It visually represents the movement of material
• How do human activities impact coastal processes?

  They can accelerate erosion and deposition rates