The Story of the

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The Story of the Norber Erratics
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The story unfolds on a hillside in Yorkshire
Large boulders of gritstone perch on plinths of
limestone
Together they tell a story which has been 16,000
years in the making
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Their exact location is here.
North of Austwick in the Yorkshire Dales National
Park
The boulders are made of gritstone carried by a
glacier from the floor of Crummack Dale about 3
kms to the north
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The hillside was scoured by the ice revealing a
pavement of limestone
..on top of which, as the ice retreated, it
deposited its load of gritstone boulders
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For 16,000 years the limestone pavement has
slowly weathered, dissolved by mildly acidic
rainwater .
..except where it has been protected by the
gritstone boulders lying on top
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Gritstone erratic
Height of the pavement at the end of the Ice Age
Plinth of limestone
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Gritstone erratic
Solutional weathering since the Ice Age
Plinth of limestone
Height of the pavement today
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But ..
How long can their plinths survive?