sub aerial processes Flashcards
Weathering and mass movement are
Sub-aerial Processes
The Holderness coast is predominately
boulder clay
This leads to particular sub-aerial processes:
Wetting and drying
At high tide the particles expand when covered with water, at low tide they dry out and contract
Repeated wetting and drying causes the clay to crumble
Freeze-thaw
During the winter months, water enters the fractures in the boulder clay
At night this water freezes and expands - due to Arctic maritime air masses
Repeated expansion and contraction, causes the cliff to be weakened
Slumping
The Holderness coast regularly experiences wet weather
Weathering leaves cracks in the boulder clay
Water enters these cracks, causing the clay to become heavier, and lubricated (slippery)
This leads to a large area of land moving downslope in one piece - known as rotational slip
Along the Holderness coast, weathering and mass movement work together, causing the fastest rate of coastal erosion in Europe
The rate of erosion is approximately
1.8m a year