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Coastal Processes (Bays and Headlands ((Cracks are widened and loose…
Coastal Processes
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Deposition
Landforms of Deposition
Beaches
Formation
A beach/strand is consists of loose particles such as boulders, pebbles, sand, mud, shingle or even shells develop along the coastline.
Most deposited materials is transported to the coast by streams, while the others formed by weathering and erosion.
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The back-shore (upper beach) has a steeper gradient and consists of coarser materials. It is only covered by the highest tides or during storms. The foreshore (lower beach) has a gentle slope and is consists of fine particles (sand and shell particle) and mud.
Beaches may be wide and gently sloping in summer, but steep-fronted and narrow in winter (stripped of sand by violent storm waves).
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Features
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Berms - ridges of coarse materials that build up on shingle beaches by constructive waves in summer. They are found below the storm beach.
Ridges - sand develop on the seaward edge of the foreshore and run parallel to the coastline., as a result of constructive waves action near the point where the wave breaks.
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Sand dunes - they develop in areas where there is a large supply of beach sand and the prevailing wind comes in from the sea. The sand dries out at low tide and is transported inland, it is trapped by obstacles and dunes are developed.
Eg Sandy beaches, backed by sand dunes are found at Gurracloe, Rosie Point and Youghal. 
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Sandspits
Sandspits - a long, narrow ridge of sand of shingle that extends into the sea and is attached to land at one end, formed by constructive waves.
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Longdrift drift is interrupted and the sediments are carried to an area of shallow, sheltered water.
Deposition extends its length across the bay, and.
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Tombolo
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Wave refraction around the island causes longshore currents to converge and deposit sand in the sheltered water between the mainland and the island.
Eg Howth is lined to the mainland by the Sutton tomboilo.
Deposition occurs along sheltered coastlines, where constructive waves are dominant.
Coastal Processes
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Destructive waves are erosional waves
Are over 1 metre high
Has a wavelength of under 20 metres
Constructive waves are depositional waves
Are under 1 metre high
Has a wavelength of 100 metres
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The processes of erosion are hydraulic action, air compression, abrasion, attrition and solution
Hydraulic Action happens when the waves create a pressure of 25 tonnes per square wave.
Most effective at points where the rock has bedding joints and faults.
Cracks are widened and rock breaks away
Air compression is when air is caught in the rocks and is compressed by the waves and then the sudden expansion of air causes an explosion
Abrasion is the most effective form of erosion here and attrition is when eroded rock particles are removed by currents and tides.
Solution is when rocks contain minerals that can by dissolved by salts in the sea
Factors are wave strength which means that the longer the fetch the more energy it has.
Shape of coastline determines the wave refraction.
Slope of shore general is is gently sloping and so has less energy.
Resistance and structure of rock, it helps to erode of resident rock lies over less resident rock
Bays and Headlands
Quartzite and granite are eroded at a slower rate than less resistant rocks such as shale and limestone.
Headlands and bays are most likely to be found in areas where there are bands of less resistant rock.
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most effective where rocks have bedding planes, joints and faults.
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