Depositional Landforms Flashcards
Define a spit
Long, narrow beaches of sand attached to land at one end and stretch across a bay, estuary or indentation in a coastline
Spit formation
Formed from LSD occuring in the dominant direct which carries beach material to the end of the beach and the onto open water
Storms build them up causing them to become more permanent
The end of the spit becomes recurved because of wave refraction and wind
If it continues to grow, a number of recurves form
Example of a spit
Orford Ness at East Anglia
onshore bars formation and example
If a spit continues to grow along an indentation, it forms an onshore bar
Forms a lagoon on the landward side
Example:Slapton sands, Devon
What are saltmarshes and how do they form?
Vegetated areas of deposited sands and clay subject to twice daily exposure as tides rise and fall
Dependent on accumulation of sediment but rates of 10 cm/yr are common
Deposition occurs when rivers slow down/lose energy as they enter the sea and due to flocculation
Example of saltmarsh
Pasturefields saltmarsh, west midlands
What are deltas, how do they form and what types of environments are they most likely to form in?
Large areas of sediment found at a river’s mouth. Crisscrossed by branching networks of distributaries.
Sediment deposited by rivers or tidal currents at a rate faster than tides can remove them
Typically form in low energy environments, low tides and when rivers in lower course are carrying lots of sediment
Example of delta
Nile delta
Tombolo formation. Give an example of a tombolo and when did it form?
They are beaches that connect the mainland to an offshore island
Often formed from spits which continue to grow seawards until they reach and join an island
Another possible explanation is the onshore movement of sediment leading to its formation.
EXAMPLE: Chesil beach near Weymouth, Dorset formed 6000 years ago
