Testing if the Processes of Desposition are Stronger than Processes of Erosion on the Beach
Aim 1- Destructive or Constructive enquiry:
Aim 1
To test if processes of deposition are stronger than processes of
erosion on the beach.
The first aim was carried out at site 2 on Deal beach, by the Groynes.
This was mainly because we needed the Groynes to assist us in the
investigation. The other site could have been suitable as well, but
where my group was specifically positioned, the pier was there and
that could have interfered with our results.
There was a purpose of this particular aim - to discover what was
shaping deal beach on the day of our visit. To successfully do this,
we had to se if the beach was being destructed by erosion or if it was
being constructed by deposition. The only way we could do this way by
counting how many waves were producing and breaking per minute on the
beach.
Theory
On the British coastlines, waves are responsible for pretty much all
of the erosion. When a wave approaches the coast, it is slowed by
friction from the seabed, but the top part of the wave will continue
at its constant speed. The wave has nothing underneath it to support,
it, so it will have to fall, and crash against the beach itself, or
even a cliff face. Depending on whether the wave is constructive or
destructive, it will either erode or deposit materials onto the beach.
We worked out that if there was more than 10 waves per minute, then
the wave was destructive (eroding the beach) but if there were less
than 10 waves per minute, then the wave was constructive (depositing
materials on the beach) On the day of the visit, if the waves were
constructive, then the swash would have been stronger than the
backwash and more of the load would end up being deposited on the
beach.
Figure 1 - wave formation of a constructive wave
[image - constructive waves]