Holderness Coastline
Geology
Defending the coast
Find out more The Holderness Coastline is in the North of England
and runs between the Humber Estuary in the south and a headland at Flamborough
head. It has the unenviable reputation as the number one place in Europe
for coastal erosion, and in a stormy year waves from the North sea can remove
between 7 and 10m of coastline.
It is one
of the fastest eroding coastlines in
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The geology
runs in bands, with a chalk layer at Flamborough in the North, Boulder
clay or till (laid down in the last ice age) south of that and finally
river deposits in the Humber Estuary. Because
the clay is an unconsolidated WEAK mass of clay particles and boulders
it erodes more rapidly than the more resistant rock of chalk in the
north. The processes of erosion and weathering occurring are numerous
but include hydraulic action, freeze thaw, abrasion, solution and
carbonation (on the clay) This has left a bay where the clay is and a headland jutting out to sea at Flamborough head. Although wave refraction focuses the waves energy on the layered and faulted rocks of Flamborough head, eroding the calk, the incredibly weak nature of the clay still means that it erodes faster than the chalk. The chalk headland has stumps and blowholes. |
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Defending the Holderness Coastline There is a debate about whether or not human beings should attempt to defend coastlines. In the case of the Holderness coastline, its geology (weak clays) waves (destructive during North Sea storms) and Geomorphology (the shape of the coastline allows the waves to break at the base of the cliffs) make erosion almost inevitable. However some defences have been attempted. Mappleton is a small village that could become village number 30 lost to the sea. The road running through it, the B1242 links towns along the coastline and would have been lost to coastal erosion if protection measures were not put into place. It was decided t6hat the cost of coastal defence for a village of only 100 people was less than the cost of building a new road. So, blocks of granite were brought in and placed along the cliff base and 2 rock groynes were put into place to trap sediment moving because of longshore drift.
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View The Holderness coastline in a larger map |
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