10.7 Caves, arches and stacks

Question 1

Where are caves, arches, stacks and stumps found

Answer 1

On a headland

Question 2

Describe the formation of caves, arches, stacks and stumps

Answer 2

1. the headland comes under attack from the waves particularly through the process of hydraulic action
2. The constant pounding creates a fault in the cliff. Further erosion of the fault creates a cave
3. When a cave is eroded from both sides of the headland this creates an arch
4. Overtime the arch becomes too heavy to be supported and collapses due to gravity, leaving a stack
5. The stack is undercut by the waves and eventually falls into the sea to form a stump, visible at low tide

Question 3

Outline the characteristics of caves, arches stacks and stumps

Answer 3

• caves may be several metres high
• the arch may be unsupported and water is able to go through the gap. It is an extension of the headland
• stacks are detached pillars of hard rock which are undercut by destructive waves
• stumps are visible at low tide e.g. Old Harry’s Wife is submerged

Question 4

Example of place with caves, arches, stacks and stumps

Answer 4

Old Harry Rocks, Dorset