Coasts Flashcards
waves
water that is created into waves through friction from prevailing winds
backwash
waves as they go back from the beach at a 90* angle
swash
waves as they go onto the beach
fetch
the distance of sea between one land form and the next
constructive wave
builds up beaches and has a strong swash and weak backwash to bring sediment onto the beach, it is low energy
destructive wave
destroys beaches and has a strong backwash and weak swash to carry sediment away, it is high energy
breaking wave
where the height reaches the critical level and where the water piles over the top because the momentum is built up and then stopped by friction which makes it break
mechanical weathering
the disintegration of rocks, where this happens there will be piles of rocks by the cliff
freeze thaw
when water gets into cracks in the rocks then freezes which means the water expands making the crack bigger, this repeats until the rock breaks apart
salt weathering
sea water contains salt, when this evaporates it leaves the salt crystals behind which grow and expand putting pressure on the rock and making it flake away
chemical weathering
where acid rain corrodes the alkali rock
carbonation
an example of chemical weathering, dissolved co2 from the atmosphere makes rainwater slightly acidic which dissolves the alkali rocks
biological weathering
due to actions of flora and fauna such as plant roots growing in cracks and animals burrowing in the holes
weathering
the earring away of rock without it being removed
mass movement
the downward movement of sliding of material under the influence of gravity
rock fall
fragments of rock break away from the cliff face, often from freeze thaw, fast and dry
landslide
blocks of rock slide down the hill, slow and dry
mudflow
saturated soil and weak rock flow down a slope, fast and wet
rotational slides
slump of saturated soil and weak rock along a curved slip plain
erosion
wearing away of rock and being taken away, high energy
hydraulic action
the motion of air being forced into cracks by waves which then forces the cracks to grow
abrasion
the rocks are carried and rub against the cliff like sandpaper
corrasion
rocks are carried and thrown at the cliff which gouges out holes
solution/corrosion
soluble chemicals are dissolved
attrition
the rocks knock against each other as they are transported which makes them smaller and smoother/rounder
cavitation
explosive force of air in the crack
transportation
how the rocks are carried, normally high energy
traction
rolling the rocks
saltation
bouncing
suspension
carried along on top