Beaches are formed by the accumulation of sediment deposited between l-- s----- t---- and the h------ point reached by s---- w----
low spring tides
highest
storm waves
1 of 12
Name 3 inputs into the beach store
beach nourishment by humans
cliff and dune erosion
river sediment
longshore transport
onshore transport
2 of 12
Name 3 outputs from the beach store
wind and storm over wash
dredging and sand mining (people)
longshore transport
offshore sediment
3 of 12
What is a swash aligned-beach and how is it formed?
These beaches are formed through waves approaching the beach parallel to the shore
wave refraction reduces energy - deposition
4 of 12
What is the difference in material deposited by low and high energy waves when concerning swash-aligned beaches.
low energy - deposit sand or mud
high energy - transport sand leaving coarser shingle
5 of 12
What is a drift-aligned beach and how is it formed?
These beaches are formed by waves approaching the coast and an angle.
LSD moves sediment along the beach - spit (store)
The waves have enough energy to keep the sediment moving, growing the beach.
6 of 12
Why is equilibrium important concerning drift-aligned beaches?
without a steady supply of sediment, LSD would ***** material faster than it was deposited.
7 of 12
Name 3 features of sandy beaches
smaller particles
wide
flat
sand becomes compact when it gets wet
little percolation
8 of 12
Why do sandy beaches allow for ridges and runnels to develop at the low-water mark?
Little percolation = less friction during LSD
This allows more deposition
9 of 12
Describe a summer profile beach and the processes that lead to its development.
1) sediment is added by constructive waves
2) steeper due to more sediment being deposited
3) wide beaches - weaker backwash
10 of 12
Describe a winter profile and the processes that lead to its development.
1) destructive waves take sediment off the beach
2) Berms eroded by plunging wave
3) high energy swash
4) off shore bars
5) strong backwash leading to rip currents
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