Weathering

Question 1

what is weathering?

Answer 1

the breakdown of rocks over time and leading to transfer of material into littoral zone

Question 2

what is an example of positive feedback?

Answer 2

rate of removal of weathered rock from base of cliff is higher than rate of weathering -> promotes further weathering as area of exposed rock is increased

Question 3

what is an example of negative feedback?

Answer 3

removal of weathered rock from the base of the cliff is slower than weathering -> build up of debris at base -> reduced weathering as cliff is protected

Question 4

What are the 3 types of weathering?

Answer 4

Mechanical, Chemical, Biological

Question 5

What are the types of mechanical weathering? (3)

Answer 5

Freeze-thaw
Salt Crystallisation
Wetting and drying

Question 6

explain freeze-thaw

Answer 6

water enters cracks in rocks and then the water freezes and expands in volume, causing cracks to widen

Question 7

explain salt crystallisation

Answer 7

as seawater evaporates, salt is left behind. salt crystals grow over time, which widens cracks

Question 8

explain wetting and drying

Answer 8

rocks (like clay) expand when wet and contract when drying, causing rocks to break up