Geography exam summer 25 - coastal landscapes

G

Swash

Is the water that moves up the shore. It occurs when waves break on the beach and carry water and sediments forward.

Backwash

Is the water that flows back down the beach after a wave has broken, returning water and sediments to the sea.

Constructive waves

are waves that build up the beach by depositing sand and other sediments. They have a strong swash and a weak backwash.

Destructive waves

are waves that erode the beach by removing sand and other sediments. They have a weak swash and a strong backwash.

Hydraulic action

is a process of erosion where the force of water (waves) impacts against the coast, often causing rocks and sediments to break away.

compressed air

is a process of erosion that occurs when waves crash against a rock face, forcing air into cracks. This pressure can cause the rock to become weak and break apart.

Abrasion

is a process of erosion caused by waves picking up and throwing sand, rocks and pebbles against the shore, wearing away the rock surface.

Attrition

is a process of erosion in which rocks and pebbles collide with each other in the water, breaking down into smaller and smoother pieces until they turn into fine sand

solution

happens when seawater which contains salt, gradually dissolves rock on the coastline

Longshore drift

is the process by which sediment is transported along a coastline by waves approaching at an angle and the swash and backwash. This results in the gradual movement of sand and shingle down the beach.

How cliffs form

Cliffs form when destructive waves erode the coast this creates a wave cut notch, a wave cut platform develops at the base of the cliff overtime erosion continue this causes the rock above the platform to fall and create a cliff.

Bays and headlands

form in areas where there is both soft and hard rock, the soft rock erodes quickly leaving an indent in the coast known as a bay the hard rock is left jutting out this is known as a headland

Sea cave

starts off as a wave cut notch that is eroded in the base of the cliff, soft rock is eventually worn away leading to a sea cave being formed from the notch

Sea arch

if erosion of the sea cave continues to the other side of the bay it creates a sea arch

sea stack

when the roof of a sea arch collapses it leaves a sea stack separated from the headland

sea stump

forms when a sea stack is eroded over and over forming a small stump separate from the headland

Blowhole

A vertical tunnel that forms when waves erode a sea cave at the base of a cliff, causing water to be forced upwards and out through an opening above.

Beaches

is a gently sloping area of sand and shingle on a coastline, formed by deposition. when waves break the swash carries material up the shore and deposits it to form the beach.

sand dunes

are hills of sand formed by the wind, where sand is accumulated and gathered by wind. The sand is trapped by vegetation.

tombolo

a landform caused by the deposition of sand that connects an island to the mainland or to another island. when waves approach an island from opposite directions they cancel each other out

Sand spit

is a deposition landform that extends from the coast into the water, created by longshore drift.

lagoon

Over time longshore drift will continue to move sediment along the coast. the spit will develop into a sand bar, separating the bay from the sea this forms a salt lake

Groynes

are concrete or wooden walls made at a right angle to the sea. this reduces the impact of longshore drift

Rock armour

are large boulders placed at the base of cliffs or sand dunes. they reduce the erosion power of the waves

Sea walls

are built at the back of beaches to protect coastal towns. the walls are sometimes curved to turn the wave back on itself

Gabions

are wire mesh cages filled with rocks, used to absorb wave energy they’re usually placed at the back of beaches and sand dunes