Zusammenfassung der Ressource
Causes of Collapse
at Christchurch
- A large fetch
means that
prevailing winds
cause huge
destructive waves
- This leads to
rates of erosion of
up to 2 metres a
year!
- The weak sand and
clay cliff are not very
resistant to erosion
- Buildings on top of
the cliffs have also
increased the weight,
so making collapse
more likely
- The cliffs are being eroded at the base
from coastal erosion, and at the top
from weathering.
- There is a large Groyne ts Hengistbury
Head to build up the beaches around
Bournemouth, and this has stopped the
supply of beach material further down
the beach at Barton-on Sea
- The cliffs at Barton are made from
sand and clay, so when it rains the
water soaks through the sand and
stops at the clay. This means that lots
of weight is added to the cliffs, and
leads to extra slumping
- Small streams also
increase the amount of
water entering the cliffs
- The arrangement of rocks
also causes water to 'pond
up'