Coasts: Weathering

Question 1

Shattering

Answer 1

Expansion and contraction of rock as temperature changes daily

Mechanical/physical weathering

Question 2

Freeze-thaw

Answer 2

Water seeps into joints/cracks and freezes, expanding by 9%

Mechanical/physical weathering

Question 3

Crystallisation

Answer 3

Waves break and slap against cliff, water evaporates leaving sodium and magnesium that form crystals which exert pressure on rock

Mechanical/physical weathering

Question 4

Oxidation

Answer 4

Chemical reaction with iron minerals in rock

Chemical weathering

Question 5

Carbonation

Answer 5

Slow dissolution of limestone due to rainfall

Chemical weathering

Question 6

Hydrolysis

Answer 6

Minerals breakdown due to reaction with water

Chemical weathering

Question 7

Seaweed acid

Answer 7

e.g kelp, releases sulfuric acid when cells break, which dissolves rock

Chemical weathering

Question 8

Molluscs

Answer 8

Live on rocks, bore holes into rock for food

Biological weathering

Question 9

When is mechanical weathering strongest?

Answer 9

Low rainfall, low temperature

Question 10

When is chemical weathering strongest?

Answer 10

High rainfall, high temperature

Question 11

When is biological weathering strongest?

Answer 11

Increases with rainfall and temperature