Coasts - Features of deposition Flashcards
What are depositional land forms made from?
Unconsolidated sediment
How can dramatic changes occur?
- High tidal ranges
- Storms
- Tsunami
How does vegetation play a key role in deposition?
Stabilises unconsolidated material and encourages further deposition
What are depositional land forms?
- Beaches
- Spits
- Sand dunes
- Salt Marsh
- Offshore Bars
- Tombolos
- Delta
What is a beach?
- A shoreline formed unconsolidated material like shingle/sand
- Accumulation of sediment between lowest and highest tide
Where does beach material come from?
- 5 % offshore bars
- 5 % cliff erosion
- 90 % rivers
What can beaches be made from?
- Sand - gentle gradient
- Shingle - steep gradient
What types of beaches can you get?
- Swash aligned
- Drift aligned
What are micro-features of a beach?
- Beach cusps
- Storm ridges
- Berms
- Runnels
- Offshore ridge
What is a spit?
Spits are long extended stretches of sand or shingle attached to the land at one end and go beyond the coastline
How are spits formed?
LSD
How does the spit become recurved?
Wave refraction or change in wind direction
Why is the spits length limited if it forms across an estuary?
The outward flow from the river currents
What can form behind a spit?
Salt marsh
What is a double spit?
Can form when deposition happens at both ends of the bay
