coastal processes marine

Question 1

wave action

Answer 1

• wind blows over sea and friction from sea bed = lean and break onto beach
• height/strength of wave:
  1. fetch = distance over sea
  2. amount of time wind blows
  3. strength of wind

Question 2

wave types

Answer 2

destructive, constructive

Question 3

destructive wave

Answer 3

• strong backwash
• weak swash
• short wavelength
• high height
• high frequency
• drags material

Question 4

constructive wave

Answer 4

• strong swash
• weak backwash
• long wavelength
• low height
• low frequency
• deposits material

Question 5

erosion

Answer 5

(destructive waves - along coast)
1. hydraulic action - waves hitting coast
2. attrition - material is carried by waves and hit each other - break
3. abrasion - waves pick up material - hurl
4. corrosion/ solution - seawater=acidic - dissolves rock

Question 6

deposition

Answer 6

material is left

Question 7

transportation

Answer 7

1. traction - large rocks rolled (seabed)
2. saltation - small rocks bounce along sea bed
3. suspension - fine material is carried by sea
4. solution - dissolved material carried by sea

Question 8

longshore drift

Answer 8

• prevailing winds approach beach at an angle
• swash: carries material up beach at same angle
• backwash: carries material down (90degrees)
• repeat: zig-zag movement