Coasts

What is a coast

a narrow strip of land adjoining the sea

What are the two types of coasts

Discordant and cordant

What are the three main coastal processes

Erosion, transportation, and deposition

What is erosion

The wearing away and removal of rocks and soil by waves

What is transportation

The movement of sand and other materials along the coast

What is deposition

The dropping or laying down of materials carried by waves when they lose energy.

Types of coastal erosion

Hydraulic action, abrasion, attrition,solution, cavitation

What is hydraulic action

When waves hit the rock. And the force causes the rocks to break apart.

What is abrasion (corrasion?

Rocks and sand carried by waves rub against cliffs wearing them away

What is attrition

When rocks hit against each other, breaking into smaller pieces

What is solution (corrosion)

When seawater dissolves rock

What are the two types of waves

Constructive and destructive

What are the characteristics of constructive waves

Strong swash, weak backwash, long wavelength, builds up beaches, less than 10 waves per minute

Characteristics of destructive waves

weak swash, strong backwash, erode beaches, 10 or more waves per minute

What are the four ways waves transport materials

Traction, saltation, suspension, solution

What is traction

Large rocks roll along the seabed

What is saltation

Small rock bounce along the seabed

What is suspension

Small materials carried within the water

What is solution

Dissolved materials carried in the water

What is longshore drift

The movement of sand and other materials along the coast by waves approaching the shore at an angle

What are some coastal erosional landforms

Headlands, bays, cliffs, stacks, caves, arches, stumps

What are some coastal depositional features

Beaches, spits, bars, tombolos

What are some coastal protection

Sea walls, groynes

What is a sea wall

A concrete wall built along the coast to reflect waves and protect the land

What is a groyne

Barriers built at right angles to the beach to trap sand moved by longshore drift

What is longshore current

Movement of water alongside the coast

What is the sequence of erosional features

Crack, cave, arch, stack, stump

what is the shore

area where the land meets the water

what is longshore drift

movement of materials along the shore

what is constructive wave

wave that builds up the shore

destructive wave

waves that destroys the shore

what is foreshore

area of the land closest to the sea

what is backshore

are of the land closest to the coast

backwash

water that runs back into the sea

what is swash

breaking waves running up the shore

what is the trough

lowest part of a wave

what is the fetch

open area of water which the wind blows

longshore current

movement of water flowing parallel to the shoreline

factors that determine wave energy

the fetch, the duration, the strength of wind

what are currents

bodies of water moving through the sea in a certain direction either vertically or horizontally

what is a wave

the circular motion of water in the sea

factors affecting marine erosion

hardness of the rock, time, human action

how are blowholes formed

waves pound on a sea cave and trap air in the cracks and joints of the rock. the compressed air exerts pressure on the cracks and joints. when the waves move backward and the air expands. overtime the rocks break down and an opening called a blowhole is formed at the roof of a cave.

how is a geo formed

when a blowhole enlarges until the cave collapses resulting in a deep long and narrow inlet

what is an inlet

a narrow body of water that reaches to the land to join a larger body of water

what are characteristics of constructive wave

long wavelength, short wave height, strong swash, weak backwash, less than 10 waves per minute

characteristics of destructive waves

short wavelength, tall wave height, weak swash, strong backwash, 10 or more waves per minute