cicle test2 Flashcards
what are the steps of sedment being tranprted
1 suspension 2 solution 3 traction 4 saltation
what is suspension ?
Suspension is where small particles such as silts and clays are suspended in the flow of water.
What is solution?
Solution is when minerals in rocks are dissolved in seawater and then carried in solution. This is not visible. Eg. chalk and limestone.
What is traction?
Traction is where pebbles and larger material are rolled along the seabed.
What is saltation?
Saltation is where small pieces of shingle or large sand grains are bounced along the sea bed.
How is it decided which method of transportation will be used for the sediment?
It depends on the size of the sediment and the energy of the environment.
What is longshore drift?
Longshore drift is the transportation of material along a coastline by wave action.
Describe the action of longshore drift.
Waves approach the coast at an angle, controlled by the direction of the prevailing (most dominant) wind. Swash is where a wave breaks and carries the sand and pebbles onto the beach. Backwash is the backward movement of seawater, which draws the sediment back down the beach at right angles to the coastline.
What is deposition?
Deposition is the laying down of materials, such as sand and pebbles, which is being transported by the sea.
How are beaches formed?
Beaches are made up of sand, shingle and pebbles. They are formed over time as eroded material is transported by longshore drift, which is then deposited by less powerful waves with the waves’ swash.
What is a spit?
A spit is a long, narrow ridge of sand or shingle, one end attached to the land while the other end projects out to sea.
How are spits formed?
They are formed by material as it is transported along the coast by longshore drift. Material is deposited where there is a bend in the coastline or a river mouth occurs. This forms a ridge over time that extends into the sea. The tip is affected by changing winds and therefore waves which can create a hook.
How is a saltmarsh created?
If the area behind a spit is sheltered, silt and mud can be deposited leading to the creation of a saltmarsh.
How is a bar formed?
When a spit continues to extend across the entrance to a bay or river mouth, it becomes a bar. It traps fresh water behind it, forming a lagoon.
How are coastal landforms created through abrasion?
it scrapes across the edge of the cliff
