Coasts part 2- landforms, management and SL

Question 1

Factors affecting rate of erosion

Answer 1

-Waves
-Rock type/structure
-Sub-aerial processes
-Presence/absence of a beach
-Coastal management

Question 2

Development

Answer 2

How different processes operate to change the physical characteristics of an area

Question 3

Landscape

Answer 3

The big picture; entirety of the sea, coast and rolling countryside

Question 4

Landforms

Answer 4

Individual components of the landscape; cliffs, wave cut platform etc.

Question 5

3 ways of classifying coastlines

Answer 5

-Concordant and discordant
-Cliffed coast, flat coast, graded shoreline
-Emergent or submergent coastline

Question 6

Discordant coastline

Answer 6

Rock bands alternate between hard and soft rock and are at a right angle to the coastline

Question 7

Headlands and bays on a discordant coastline

Answer 7

Differential erosion of hard and soft rock results in bas being created where soft rock was and leaving headlands jutting out into the sea

Question 8

Concordant coastline

Answer 8

Alternating bands of hard and soft rock that run parallel to the coastline

Question 9

Headlands and bays on a concordant coastline

Answer 9

Waves break through a weaker crack in the hard rock and create bays as the soft rock erodes faster

Question 10

What is a cliff

Answer 10

A mass of resistant rock

Question 11

What is a wave cut platform

Answer 11

A gently sloping platform of rock stretching out from the cliff to the sea (with an angle of less then 5 degrees)

Question 11

Formation of a cliff

Answer 11

Land is weathered and eroded through hydraulic action and abrasion to create a drop between the land and the sea

Question 11

Formation of a wave cut platform

Answer 11

Waves focus erosion between the high and low tide levels through abrasion and hydraulic action. This leads to a wave cut notch growing until the cliff is completely undercut

Question 12

What is a geo

Answer 12

A narrow, steep sided inlet or gorge typically found on hard rock cliffs

Question 13

Formation of a geo

Answer 13

Created when a fault line is differently eroded to form a gully, though it may begin as a sea cove. Faults are enlarged by ,marine erosion through hydraulic action and abrasion

Question 14

What is a blowhole

Answer 14

Vertical clefts or splits in coastal cliffs which link sea caves to the cliff top

Question 15

Formation of a blowhole

Answer 15

Formed along coastlines due to hydraulic action; incoming waves trap and compress air within a cave and repeated force can puncture the roof of the cave and water and spray will be driven through the roof of the cave.

Question 16

Swash aligned beaches

Answer 16

Sediment moves up and down the beach with little lateral transfer; this happens when the waves break parallel making curved and concave beaches.

Question 17

Drift aligned beaches

Answer 17

Produced where waves break at an angle to the coast; swash occurs at an angle but backwash is perpendicular to the beach. Material is transferred by longshore drift.

Question 18

Shingle beach profiles

Answer 18

Steeper as more water drains between the air bubbles between the rocks making the backwash less effective at dragging sediment down the beach. Sediment is also harder to move on a shingle beach.

Question 19

Sandy beach profile

Answer 19

More gentle profile due to sediment being lighter and easier to move.

Question 20

What is a berm

Answer 20

Ridge of sand indicating the high tide mark

Question 21

Formation of a berm

Answer 21

Constructive waves push sediment up the beach and deposit it

Question 22

formation of sand ripples

Answer 22

Formed as the tide goes out, only on sandy beaches and only visible at low tide

Question 23

What are runnels and ridges

Answer 23

Naturally raised sand are ridges and runnels are the water between ridges

Question 24

Formation of runnels and ridges

Answer 24

Naturally raised sand forces waves to slow down and deposit sand leaving water to get trapped in the runnels

Question 25

What is a cusp

Answer 25

Shoreline formation made up of various grades of sediment in an arc pattern

Question 26

Formation of a cusp

Answer 26

Form in bays as the tide comes in, waves refract, energy spreads out so some areas have a stronger swash

Question 27

What is a barrier beach

Answer 27

Where a beach or spit extends across a bay to join two headlands; they can also trap water behind them to form lagoons

Question 28

Formation of a barrier beach

Answer 28

Barrier beaches on the South coast of England are believed to have been deposited following a rise of sea levels after the last glacial period. Longshore drift has added more material and has reworked the sediment.

Question 29

What is an offshore bar

Answer 29

Bar is a generic term for a range of sediment accumulations in a coastal area; elongated deposits of sand or shingle, often lying parallel to the coastline

Question 30

Formation of an offshore bar

Answer 30

Sand and shingle is deposited int one area by longshore drift, they are only visible at low tide

Question 31

What is a barrier island

Answer 31

Island of sand and shingle, with a series of dune ridges on the seaward face.

Question 32

Formation of a barrier island

Answer 32

Sand accumulates on an offshore bare eventually making it visible at all times, tidal currents can seep through into the lagoon behind. Tidal currents and river flows in the lagoon can lead to erosion and deposition

Question 33

What is a spit

Answer 33

An accumulation of sediment off a coastline that juts out into the sea

Question 34

Formation of a spit

Answer 34

Formed by longshore drift on low energy coastlines

Question 35

What is a tombolo

Answer 35

A beach or ridge of sand and shingle that’s formed between a small island and the mainland

Question 36

Formation of a tombolo

Answer 36

Deposition occurs when waves lose their energy and the tombolo begins the build up, they may be covered at high tide