Coasts defenitions

Question 1

Abrasion

Answer 1

Waves scrape away the coastline by throwing sand and stones against the coast. It is a type of sea erosion

Question 2

Air compression

Answer 2

A type of sea erosion whereby air gets trapped in small cracks as waves crash against the coast. When the wave moves away the air is suddenly released. This causes constant compression and expansion of rock which eventually crumbles away

Question 3

Arch

Answer 3

The piece of land left hen two caves join together through a headland

Question 4

Arrition

Answer 4

A type of sea erosion whereby stones carried by the sea are rolled around on the shore by the waves. They becomes smaller and rounder as they are knocked together in the seaB

Question 5

Backshore

Answer 5

The backshore area of a beach extends from the high water mark to the dunes. It is only affected by waves during exceptional high tides or severe storms

Question 6

Backwash

Answer 6

The movement of a wave back out to sea

Question 7

Bay

Answer 7

A large curve in the coastline, e.g. Dublin Bay

Question 8

Bay head beach

Answer 8

The bay that forms in a bay

Question 9

Beach fabric

Answer 9

The material that forms a beach. May be sand, shells and shingle. Shingle is a
stony mix of pebbles and cobbles

Question 9

Beach

Answer 9

An area of sand and shingle that forms in a sheltered coastal area. It is a landform of coastal deposition.

Question 9

Beach mats

Answer 9

Form of soft coastal protection. Rubber or textile mesh matting placed on the
backshore to trap windblown sand and encourage marram grass growth.

Question 10

Beach nourishment

Answer 10

Beach nourishment (or beach recharging) involves importing of sand or gravel to replace losses of sand due to erosion.

Question 11

Berms

Answer 11

Long ridges on a beach formed by constructive waves. Mark the boundary
between the foreshore and backshore

Question 12

Blowhole

Answer 12

Chimney-like hole in the roof of a cave. These holes are formed by air compression

Question 13

Breakwater

Answer 13

A hard method of coastal protection. A concrete barrier placed in front of a beach to reduce the force of destructive waves and provide shelter.

Question 14

Cave

Answer 14

A hollow eroded into a rocky coastline by destructive waves

Question 15

Cliff

Answer 15

A steep wall on a rocky coastline formed by coastal erosion processes, e.g. Cliffs of Moher CO Clare.

Question 16

Constructive waves

Answer 16

A wave whose swash is stronger than its backwash

Question 17

Cusp

Answer 17

Crescent-shaped hollows on the seaward edge of a berm

Question 18

Destructive wave

Answer 18

A wave whose backwash is stronger than its swash

Question 19

Fetch

Answer 19

The distance a wave travels before it reaches land

Question 20

Foreshore

Answer 20

The lower part of a beach from the high tide mark to the sea

Question 21

Gabion

Answer 21

A hard method of coastal protection. Gabions are wire cages filled with rock used to
protect the coast from erosion

Question 22

Geo

Answer 22

A long narrow inlet formed when a cave roof collapses in a rocky coast

Question 23

Groyne

Answer 23

A soft method of coastal protection. Groynes are wooden or concrete walls placed perpendicular to the beach. They trap sand by interrupting the flow of longshore drift

Question 24

Headland

Answer 24

A piece of land jutting out into the sea, e.g. Loop Head, County Clare

Question 25

Hydraulic action

Answer 25

A type of coastal erosion process whereby the force of the waves wears the land away

Question 26

Lagoon

Answer 26

The lake formed when a sand spit seals off a bay from the sea. They also form when a sand bar is deposited across a bay, e.g. Lady’s Island Lake, County Wexford

Question 27

Longshore drift

Answer 27

The movement of sediment along the shore by coastal sea currents

Question 28

Notch

Answer 28

The long cave that forms at the base of a cliff due to the action of destructive waves

Question 29

Marram grass

Answer 29

Grass that has adapted to grow in the salty conditions on beach dunes. It helps trap windblown sand and encourages beach formation

Question 30

Revetments

Answer 30

Sloping banks built to absorb the energy of waves. They are a hard method of coastal protection

Question 31

Rock amour

Answer 31

Large 1- 2 tonne boulders placed to protect coastlines and structures such as piers from erosion

Question 32

Runnel and ridge

Answer 32

A runnel is a long shallow depression in the sand of the beach foreshore. A ridge is a long low mound of sand that forms in the foreshore. They run parallel to the coast

Question 33

Sand dune

Answer 33

A line of sand hills covered in marram grass that form at the extreme backshore

Question 34

Sand fences

Answer 34

Wooden fences built in the backshore to help trap sand and stabilise sand dunes. They are a soft method of coastal protection

Question 35

Sand spit

Answer 35

Long deposits of sand attached to the land at one end

Question 36

Sea stack

Answer 36

A tall tower of rock that is left when a sea arch collapses

Question 37

Sea stump

Answer 37

A small rocky mound that remains when a sea stack has been eroded away

Question 38

Sea wall

Answer 38

A curved concrete wall built to protect valuable areas of coast from destructive waves. They are a hard method of coastal protection

Question 39

Slumping

Answer 39

The collapse of soft coastline material such as boulder clay

Question 40

Solution

Answer 40

Type of sea erosion whereby the sea dissolves rock away

Question 41

Storm beach

Answer 41

A stony beach at the top of the backshore. It forms when powerful winter storm waves throw stones onto the backshore

Question 42

Tombolo

Answer 42

A ridge of sand and gravel that connects an island to the mainland, e.g. Sutton Tombolo, County Dublin

Question 43

Wave built terrace

Answer 43

A ridge of stones deposited underwater at the seaward end of a wave-cut platform

Question 44

Wave cut platform

Answer 44

The flat rocky area of shoreline at the base of a cliff. It represents the original base of a cliff. Exposed at low tide