Coasts Flashcards
(25 cards)
Swash
the movement of water up the beach after a wave breaks
Backwash
the movement of water back down from the beach to the sea
Erosion
wearing away of the Earth’s surface by agents such as wind, water and human activity.
Longshore drift
the movement of sand and other materials along a beach
Slumping
a type of mass movement where saturated soil and rock slide down a curved surface, often after heavy rain. It usually happens on soft cliffs like clay.
Rockfall
when bits of rock break off a steep cliff face, often due to weathering (like freezing and thawing), and fall straight down.
Hydraulic Action
When waves crash against the coast and force air into cracks in the rocks. The pressure causes the rocks to break apart over time.
Abrasion
Abrasion happens when rocks and pebbles in the waves grind against the cliff, wearing it down like sandpaper.
Attrition
Attrition is when rocks in the water smash into each other, breaking into smaller, rounder pieces.
Corrosion
Corrosion is when seawater dissolves minerals in the rocks (especially chalk or limestone), making them break down.
How longshore drift works
Longshore drift moves material along the coast. Waves hit the beach at an angle, pushing sediment up the beach (swash), and gravity pulls it straight back down (backwash), creating a zigzag movement of sand and pebbles along the shore.
wave-cut notch
A wave-cut notch is a small dent or cut at the base of a cliff made by erosion from waves. Over time, the notch gets bigger, making the cliff unstable and likely to collapse.
spit
a narrow deposit of sand and other material which extends into a body of water
swell
the movement of waves
headland
land jutting out into the sea, usually at the end of a bay
refraction
the bending of waves caused by their contact with the sea floor and headlands
rip
water flowing out to the sea in a strong current
stack
formed when erosion causes the rock supporting an arch to collapse
deposition
the laying down of material carried, for example, by waves, ocean currents, rivers or wind
cliff
a steep rocky slope formed by waves eroding the rock face
cave
a hollow formed when weak rocks on a headland are eroded
blowholes
an opening in the roof of a cave through which water is forced by the action of waves
beach
formed by materials brought tot he shore by waves in the swash
fetch
the distance over which wind has blown to form a wave
