Chapter 3

Question 1

Sea level rise

Answer 1

Increase in global temp
Higher rates of melting to ice stores, valley glaciers etc
Global increase in volume of water
Temp rises = h20 expand
1 degree rise in mean global temp= sea level rise of approximately 2m

Question 2

Submergent landforms

Answer 2

Sea level rises
Ecstatic rise in sea level takes place faster than isostaic rebound after ice age
Flooding

Question 3

Types of submerge the landforms

Answer 3

Rias
Fjords
Shingle beaches

Question 4

Rias

Answer 4

Eg kings ridge

Submerged river valleys - winding reflects original route of river

Lowest part of the rivers course and the flood plains alongside the river may be completely drained

Higher land forming the tops of valley sides and then middle and upper port remains exposed

Exposed valley sides are gently sloping

Question 5

Cross section of rias

Answer 5

Shallower water increasingly deep towards centre

Question 6

Long section - Dias

Answer 6

Smooth profile and water of uniform depth

Question 7

Fjords

Answer 7

Eg Milford sound fjord , NZ

Submerged glacial valleys

Steep, cliff like valley sides

Water is uniformly deep, reaching 1000m plus

U shaped cross section reflects original shape of glacial valley

Glacial rock basin with a shallower with a shallower end known as the threshold

Results from lower rates of erosion at seaward end of valley where ice thinned in warmer condition

Question 8

Shingle beaches

Answer 8

When sea level falls as volume of land based ice grows and large areas of new land emerge from sea

Sediment accumulates on the surface, deposited by rivers, meltwater streams and low energy waves

As sea levels rose at the end of the last glacial period, wave action pushed these sediments onshore- beach at former cliff lines elsewhere may form bars and Tombolos

Question 9

Modification of rias and fjords

Answer 9

May be modified by the wave processes acting on their sides at sea level

Valley sides - subariel processes May lead to steepness reduction in fjords

Sea levels- rise by 0.6m in 100 years, wave depth increase and increase in marine erosion

Question 10

Shingle beaches modification

Answer 10

Longshore drift

Sea level rise increase
Storm events

Unconsolidated material - vulnerable

Question 11

Eustatic sea level change

Answer 11

Eustatic changes - changes in the volume of water in the global ocean store

Changes influenced by variation in mean global temps - affecting BOTH amount of water in ocean store and its density

Also affected by isostatic changes( land level) ( sea level change) but NOT considered here

Question 12

Factors that affect changes in global temp and water volume

Answer 12

Variations in the earths orbit around the sun , typically every 400,000 years

Variations in the amount of energy produced by sun, solar maximum every 11 years

Changes in composition of the atmosphere due to major volcanic eruptions which reduce incident solar radiation

Variations in tilt of the earths axis- every 41,00o

Question 13

Glacial

Answer 13

A time where ice coverage on earths rise to significant levels

Question 14

Inter glacial

Answer 14

Time where glaciers/ ice coverage has melted and sea levels are rising

Question 15

Climate change and sea level

Answer 15

Decrease in global temp = more precipitation as snow

Snow turns into ice and water is slowed as solid rather than returned to sea

Reduction in volume of h2o in ocean store and fall in sea level

EMERGENT landforms- inland

Question 16

Raised beach, marine terraces, and abandoned cliffs

Answer 16

Raised beaches are areas of formed shore platforms

Found inland from present shoreline- left high and dry

Behind beach - abandoned cliff with wave cut notches , caves , arches and stacks

Marine terraces are much larger scale landscape features than raised beaches which are quite small scale and localised at base of relic cliff

Terraces - form same as raised beaches - often don’t have cliffs above them

Question 17

Modification of emergent landscapes

Answer 17

After their emergence these landforms are no longer affected by wave processes

Continue to be affected by mass movement and weathering

Post glacial period = warmed and wetter= vegetation for cover

Future - more earn confusions , increased Chemical weathering- cojld lead to increased sea level = wave processes , hot= chemical ( carbonation) and biological ( organisms on surface)
AFFECTed by waves agai

Question 18

Geology at isle of purbeck

Answer 18

Green sands 
Purbeck and Portland limestone R
London clay
Kimmerage clay 
Chalk R
Bagshot bed 
Wealden sands and sands 
Blown sands

Question 19

Energy- Isle of purbeck

Answer 19

Wave processes bringing MOST of energy
Dominant wave direction is SW/S=long fetch = destructive waves
High transportation because of high erosion
Sediment trapped and deposited in bags between headlands eg lulworth and swan age
Wave height exceeds 3.5m at times

From south - concordant(P&P limestone

From east - disconcordant

Question 20

Sediment sources- Isle of purbeck

Answer 20

Portland bill to selonely bill sediment cell

Net increase of sediment

10,000 - end of last ice age = English Channel flooded= sediment

Fluvial sources - river piddle

Nearshore stores - driven into coastline during storms

Cliff- erosion

Question 21

Landforms( erosional) at Isle of purbeck

Answer 21

Headlands and bays eg st aldhems point headland and swan age bay

Stacks and stumps - chalk, eg old Harry’s rocks

Cliffs and shore platforms - Portland limestone eg golden cap

Arch - purbeck limestone eg durdle door

Question 22

Depostiional landforms at Isle of purbeck

Answer 22

Beaches
- blown sands, green sands, Wealden sands and clays eg swanage beach

Spit
- blown sands eg stud land spit

Sand dunes
- blown sands eg studland dunes

Berms
- shingle beaches