Weathering

Question 1

What is weathering?

Answer 1

The breakdown of rocks in situ

Question 2

What happens during freeze-thaw weathering?

Answer 2

During the daytime water can enter small cracks and joints in a rock. The water then freezes and causes it to expand. Pressure
increases and widens the crack. This process repeats eventually causing pieces of rock to break off.

Question 3

What happens during onion-skin weathering?

Answer 3

The high temperatures cause the outer surface of rocks to expand. During the night, when temperatures drop, the outer layer contracts. Repeated expansion and contraction causes the outer
layer of the rock to ‘peel off’. This is known as exfoliation.

Question 4

What is oxidation?

Answer 4

Rocks containing iron react with the oxygen, causing it to
oxidate and turn red. This causes the rock to disintegrate more easily.

Question 5

What is carbonation?

Answer 5

Dissolving of rocks such as limestone by weak carbonic acid that is in rainwater.