COASTS definitions Flashcards
Abrasion
A form of erosion where loose material and sediment ‘sandpapers’ the walls and floors of the river, cliff or glacier. Also known as attrition
Backshore
The upper beach closest to the land, including any cliffs or sand dunes
Bar
A section of sand caused by deposition. They all Join two side of a bay together, creating a lagoon behind the bar.
Beach morphology
The surface shape of the beach
Beach nourishment
The addition of sand and sediment to an eroding beach by human. The new material will be eroded by the sea which saved the cliffs or sand dunes from erosion and recession
Coastal recession
The retreat of a coastline due to erosion, sea-level rise or submergence
Concordant (parallel ) coastline
A coastline where band of alternate geology run parallel to the coast
Corrasion
A form of mechanical erosion where arterial and sediment in the sea is flung at the cliff face as waves break against it, this breaks up the rock making up the cliff.
Corrosion
The weak acid in seawater and some types of seaweed react it’s particular rock minerals, causing erosion and weakening
Discordant (perpendicular) coast
A coastline where bands of alternate geology run perpendicular to the shore
Dynamic equilibrium
A system where its input and outputs are in balance. Short term changes can affect this balance, negative feedback loops help to take the system back to dynamic equilibrium
Emergent coast
A coastline thats is advancing relative to the sea level at the time
Estuary
The point as where the river meets an ocean, often muddy. Sometimes estuaries become exposes at low tide or hazardous to traverse in a boat due to sandbanks
Fetch
The length of water over which the wind has travelled
Foreshore
The lower part if the beach covered twice a day at high tide ( the past of the beach that receives the more regular wave action )
Freeze thaw
A form of physical sub-aerial weathering where water freezes i the cracks of a rock expands and enlarges the crack. This weakens the rock overtime leaving it more open to erosion
Geology
The physical structure and arrangement of a rock
Glacial Erosion
The removal of loose material by glacer ice, involving abrasion etc
Groyne
A from of hard engineering. Low-lying concrete or wooden walls, constructed perpendicular to the seafront and run out to sea. They encourage the trapping of sediment to reduce erosion caused by longshoreman drift or by winds
Hard management
The use of concrete structure to reduce or halt the recession of a coastline. It incudes: groyne, sea wall and rock armour
High-energy environment
A coast where wave action is predominantly large destructive waves, causing much erosion
Hydraulic action
The pressure of compressed air forced into cracks in a rock face will cause the rocks to weaken and break apart