Coastal deposition

Question 1

What defines what a cliff looks like?

Answer 1

The type of rock that the cliff is made from determines how resistant it is to erosion and the way the layers of rock are angled.

When the rock is hard, dramatic tall cliffs can form (Cliffs of Moher)
When the rock is weaker, the erosion is faster but the cliffs are less dramatic (Houlderness coast in England)

Question 2

How are wave-cut platforms formed?

Answer 2

• The sea erodes the base of the cliff forming a wave-cut notch, between the low and high tide line, mostly by abrasion and hydraulic action. The notch increases in size and the upper cliff is undercut.
• Weather weakens the cliff which causes it to collapse. The backwash carries the rubble towards the sea forming a wave-cut platform.
• A wave-cut platform is the bedrock that is left behind as the cliff moves backwards and is only visible at low tide. The process repeats and the cliff continues to retreat.