Coasts Flashcards
What is swash?
A wave that travels towards the beach.
What is backwash?
A wave going back out to sea.
What is the fetch?
The distance a wave travels.
What is the prevailing wind?
Strongest, dominant wind direction.
How is a wave created?
- The wind blows over the sea.
- This creates ripples.
- These ripples become bigger swells.
- The swells eventually approach the land.
- The sea becomes shallower as the land gets nearer.
- The bottom of the wave slows due to friction.
- The top keeps going and forms a crest.
- The crest topples over forming a breaking wave.
What is a destructive wave?
Created by a large fetch. They are big, strong waves with high energy. Erode the coastline. Backwash is stronger than swash. 14 waves per minute.
What is a constructive wave?
Created by a short fetch. Small, gentle waves with low energy. Deposit sediment. Swash is stronger than the backwash. 7 waves per minute.
What is biological weathering?
Weakening and disintegration of rocks by plants, animals and microbes. For example, growing plant roots can exert pressure on the rock.
What is chemical weathering?
Erosion or disintegration of rocks caused by chemical reactions. For example, solubles such as acid rain dissolve and break down the cliff faces.
What is mechanical weathering?
The process of breaking big rocks into little ones. Freeze-thaw action is when water enters cracks and expands overnight, separating the rock.
What is hydraulic action?
Erosion of the cliffs caused by the force of water and air in the waves colliding against them.
What is abrasion?
Erosion pf the cliffs as waves throw particles and rocks against them.
What is attrition?
Erosion of the material carried by waves. The material in the waves is smoothed as it bumps into each other.
What is solution/corrosion?
Minerals are dissolved in the water and carried along in solution.
What is a headland?
An area of hard rock protruding out into the sea.