T3: Coastal Systems And Landscapes Flashcards
What is Hydrolysis?
Hydrolysis occurs whenwater reacts with minerals in the rock causing the chemical composition of the rock to change and become more unstable. This reaction makes the rock more susceptible to decomposition.
What is Carbonation?
Carbonation occurs when carbon dioxide from moisture in the air reacts with carbonate minerals found in rock. This creates carbonic acid which breaks down rock.
What is Solution?
Solution occurs because many minerals are soluble and are removed when they come into contact with water.
What is Hydration?
Hydration occurs when water is absorbed by minerals in the rock, creating crystals which exert pressure on the surrounding rock, eventually causing it to crumble.
What is Oxidation?
Oxidation occurs when oxygen reacts with minerals such as calcium and magnesium to form iron oxide. Iron oxide is reddish brown in colour and causes the decomposition of rock.
What is Freeze-Thaw weathering?
When water gets into cracks in the rock and at night, when temperatures fall the water can freeze. When water freezes it expands, by on average 9%, this puts pressure on the surrounding rock. This cycle will eventually put enough pressure on the rock to causes pieces to fall off.
What is Crystallisation?
Where the evaporation of water from rock surfaces leads to the crystallisation of salts. Crystallisation leads to a dramatic increase in volume which exerts pressure on the surrounding rock, and can eventually fracture the rock.
Define:
Wave Frequency
The number of waves over a given period of time
e.g. per minute
Define:
Wavelength
The horizontal distance between two adjacent crests or troughs
Define:
Fetch
The distance of the sea, over which the wind has travelled
Define:
Prevailing Wind
The most frequent/dominant wind direction a location experiences
Define:
Swash Zone
The area where the waves run up the beach
Define:
Breaker Zone
The area offshore where waves break, losing energy
Define:
Negative Feedback
When a change in the system causes other changes that have the opposite effect.
Define:
Exclusive Economic Zone
A.K.A EEZ
Where a country has national jurisdiction and owns any resources (e.g. fish, gas) up to 200 nautical miles.
Define:
Backshore
The part of the beach nearest the land often not reached by the waves, beyond the influence of the waves, above the high water mark.
Define:
Berm
A shingle (pebble) ridge
Explain:
Dynamic Equilibrium
When inputs and outputs are balanced. A change in one input/output often causes negative feedbacks that restore the system balance.
Explain:
Refraction
When the waves change direction, usually at a discordant coastline when they hit into headlands, losing energy.
Explain:
Difference between constructive and destructive waves
Constructive waves are low energy with stronger swashes than backwashes; destructive waves are high energy with stronger backwashes than swashes.
Although the swashes of destructive waves are often stronger than the swashes of constructive still.
