Mon Prof Augmenté
Sea cave, arch, stack
Age 12 · Geography
Waves strike a rocky headland and widen weak cracks in the rock. Over time the cracks become a cave, then an arch, and finally a lone stack.
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Age 12: open this week
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In the picture
- Sea cave: a hollow at the waterline in the headland
- Natural arch: a rock bridge with seawater passing through it
- Sea stack: a lone pillar of rock standing apart from the headland
Examples
- The base of a seaside cliff crumbles after a storm.
- A sandcastle edge collapses as waves wash against it.
Key takeaways
- Waves can widen cracks in rock until a cave forms.
- A cave that cuts through a headland becomes an arch; if the arch collapses, a stack remains.
Quiz: Sea cave, arch, stack (Age 12)
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In what order do the coastal features form as the sea attacks a headland?
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What first starts the formation of a sea cave in a headland?
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What remains if a natural arch collapses?
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