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 | | Pingo ponds and patterned ground are Ice Age features of the Brecks. They formed in frozen conditions over 12,000 years ago. | |
| | | | What is a pingo?
The word ‘pingo’ comes from an Eskimo word meaning ‘hill’. Pingos are found today in the arctic tundra.
They are ice mounds fed from below by groundwater which grow every winter and then melt in summer, forming a crater-like pond.
As the mounds grow the overlying soil is shifted off them to form a surrounding rim or rampart.
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| | | | | Pingo ponds
Pingo ponds formed when ice mounds in the topsoil finally melted and collapsed to form irregular pools at the end of the last Ice Age.
Most pingo ponds in the UK have been ploughed up and lost but three pingo systems remain in the Brecks - the best place to see them today is Thompson Common.
Further information
Great Eastern Pingo Trail
NCC countryside access team www.countrysideaccess.norfolk.gov.uk
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| | | | | Wildlife at the ponds
These ancient ponds are home to a unique range of wildlife species, many of them rare. Some of the beetles have survived here since the Ice Age ‘mini-mammoths’ alive and well in the Brecks.
Pingo ponds are also excellent for breeding amphibians, dragonflies and damselflies. Rushes and reeds grow in the wet areas, while ferns and mosses are at home in damp, shady places. Gorse, birch and broom live on higher, drier ground.
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| | | | | Patterned ground and vegetation stripes
Some parts of the Brecks have an intricate pattern of both sandy and chalky soils, created by frost action in the Ice Age.
This gives rise to a mix of vegetation types, spectacularly seen at sites such as Knettishall Heath, where characteristic bands of chalk grassland and acid heathland plant communities co-exist side by side.
On level ground, intense tundra activity sorted the sediments to create patterned ground. In aerial photographs these features look like fingerprints in the grass heath vegetation and soils of ploughed fields.
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