Zusammenfassung der Ressource
Depositional Landforms
- Formed by low energy waves, sand and
shingle acummilating faster than removed and
an abundant supply of material
- Beaches
- Sand - gentle gradient (5 degrees) as small
particle size doesn't allow percolation so most
of the swash is backwashed
- Ridges - when the material is carried
down the beach it creates ridges
- Runnels - created in the dips between
ridges where water acummilates
- Storm Beach
- Created by strong swash at
spring high tide at the back of
the beach
- A ridge composed by the biggest
boulders thrown by the largest
waves
- Berms - a series of ridges marking the successively lower
high rides as the cycle goes from spring to neap
- Shingle - steeper gradient (10-20 degrees) as water rapidly
percolates though shingle as it has large gaps between
sediment
- This means the is less backwash therefore little
sediment is carried back down the beach
- Cusps - semicircular shaped
depressions which form when
waves break directly onto the
beach
- Ripples - developed on the sand by wave
action or tidal currents
- Spits
- Long narrow piece of land joined to the
mainland which projects out to sea or across
a river estuary
- Longshore drift moves
material along a coastline
determined by the prevailing
wind.
- Where the coastline
changes direction the material is
carried on being deposited into the sea
- The increase depth of water will stop it
reaching the other side of mainland
- Refraction (waves bending) and a different wind
direction can cause a curved end
- If a spit does
join the other
side of land it
forms a bar
- Behind the spit is very low energy waves meaning finer
silt and mud is deposited which can be colonised by
vegetation to form a salt marsh
- Spurn head, Humberside
- Sand dunes
- Psammosere - succession that
develops on sand
- Accumulations of sand shaped into
mounds by the wind
- Dry wide sandy beaches
- Strong onshore winds to
transport sand particles through
saltation
- An obstacle traps the sand when
deposited behind is as the wind's energy reduces
- Knoll Beach, Isle of Purbeck,
Dorset SW England
- Issues
- Home to rare species of
plants and birds
- Vulnerable areas are planted
with marram grass to stabilise
the dunes
- Fire hazard - BBQ's and
cigarette ends
- Fire beaters are positioned within the dune area
- No tourist facilities
- Toilets, shops and a car
park was built
- Litter bins
- Picturesque - lots of tourists
- Board walks have been laid
through the dunes to keep tourists
off the dunes
- Information boards to
educate tourists about
the environment
- Salt marshes
- muddy shore between neap tide & extreme spring tid
- Halosere - succession in
a salt marsh
- Low energy environment & mud
- creeks - formed by the erosive power of the
water draining back to the sea at falling tide
- Coastal defence - acts as a big
sponge
- Many new salt marshes are being created due
to managed retreat e.g. Essex
- Threats
- Industry
- Being drained for agriculture
- Eustatic change
- Isostatic change
- Tombolos
- Waves refract around the island
resulting in low energy behind the island
- Material is deposited
- Joins to the land