Coastal Proccesses Flashcards
(44 cards)
What is the fetch?
The fetch is the distance a wave has travelled before it reaches the shore
What is the swash?
The swash is the wave travelling up the shore
What is the backwash?
The wave going back down the beach
What are the two types of waves?
Constructive and destructive waves
What do constructive waves do?
They build up the coastline by causing deposition of sand
When are constructive waves typical?
In calm weather
When are destructive waves typical?
In windy weather
What do destructive waves do?
They erode the coastline
What are the five coastal erosion processes?
Hydraulic action
Abrasion
Attrition
Solution
Air compression
What is air compression?
When waves hit the land air is forced into tiny cracks in the rock this constant explosive pressure and release severe weakness the rock and breaks it
When are the three instances when coastal deposition occurs?
There are constructive waves with calm weather
There is a sheltered area such as a bay
The land is gently sloping with shallow water
Name a coastal transport process
Longshore drift
What is longshore drift?
The movement of sand in a zig zag pattern from one side of a beach to the other along the coast
Name three groups of coastal landforms formed by erosion
Cliffs
Bays and headlands
Caves arches, sea stacks and blow holes
Name an example of a cliff
Cliffs of Moher in County Claire
How do cliffs form?
When coastal erosion occurs, they attack the rock at the base of the cliff
The erosion undercuts the rock forming the notch
The notch gets deeper and the rock above falls into the sea
The cliff constantly retreats
The land at the bottom of the cliff is now exposed as a rocky ledge called a wave cut platform
Name an example of a bay
Galway Bay, mizen head
How do bays and headlands occur
The erosion breaks down the soft rock at the coastline forming a curve
The areas of harder rock rode more slowly and left sticking out as headlands
What are cliffs?
Steep walls of rock formed where the sea meets the land
What are bays and headlands?
these are broad curves in the coastline and headlands are bits of land extending out into the sea
What is wave refraction?
When waves curve and are sent backwards
Why do bays usually have beaches?
Because as the bay gets larger, the waves loose energy and deposit sand on the shore
Where are caves arches sea stacks and blow holes found?
The coast of North Mayo
How do you caves arches sea stacks and blow holes form?
When headlands are eroded by hydraulic action
