glaciation in snowdonia some post glacial changes
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Glaciation in Snowdonia
-Some Post-Glacial Changes to the
Landscape
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Snowdonia – Post Glacial Changes
Post-glacial screes due to frost shattering on the slopes above.
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Snowdonia – Post Glacial Changes
Fluvial erosion has cut through the morainic deposits in Cwm Idwal.
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Snowdonia – Post Glacial Changes
Lakes have been infilled as shown by these lake deposits in the Nant Ffrancon valley.
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Snowdonia – Post Glacial Changes
Soils and vegetation have developed on both the bare rock and morainic surfaces left after the ice retreated.
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Snowdonia – Post Glacial Changes
Grazing by sheep has resulted in a distinctive grassland flora; trees and heather only occur where sheep are unable to graze.
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Snowdonia – Post Glacial Changes
Footpath erosion is a problem in many popular sites.
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Snowdonia – Post Glacial Changes
Many paths have been paved, as in Cwm Idwal.
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Snowdonia – Post Glacial Changes
Where walkers keep to the path the surrounding vegetation is able to recover from erosion.
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Snowdonia – Post Glacial Changes
The small, old Cwm Dyli H.E.P. scheme has left a pipeline eyesore; The new scheme at Dinorwig is hardly visible.