Enquiry 1 Why Are Coastal Landscapes Different And What Processes Cause These Differences

Question 1

Littoral zone

Answer 1

Wider coastal zone including adjacent land areas and shallow parts of the sea just offshore

Question 2

Dynamic environment

Answer 2

Coasts are a boundary zone (marine and terrestrial interact)

Extreme events (storms/tsunamis)

Human development (residential / tourism)

Question 3

Backshore

Answer 3

Above high tide level and only effected during exceptionally high tides

Question 4

Foreshore

Answer 4

Waves usually confined here

Question 5

Nearshore

Answer 5

Shallow water areas

Intense human activity

Question 6

Offshore

Answer 6

Beyond influence of waves

Question 7

Classified with longer term criteria

Answer 7

Geology (rocky sandy estuarine concordant discordant)

Seal level change

Tectonic processes lift land= local sea level rise

Climate change = rise and fall

Classify as submerging or emergent

Question 8

Outbuilding coastline

Answer 8

Deposition > erosion

Net gain of sediment

Question 9

Eroding coastline

Answer 9

Erosion> deposition

Net loss of sediment

Question 10

Rocky coasts

Answer 10

High energy

Waves (long fetch/destructive)

Landforms (cliffs/wave cut platforms)

Atlantic

Processes (erosion/mass movement)

Clifford coastline (flamborough head)

Question 11

Coastal plain landscapes

Answer 11

Low lying

Young sedimentary rock

Low energy

Waves (short fetch/ constructive)

Processes( lsd and deposition)

Landforms (beaches/ berms)

Mediterranean

Question 12

Sandy coastline

Answer 12

Studland bay

High tide and sandy beach is inundated

Dune vegetation stabilises coast and prevents erosion

Question 13

Estuarine coastline

Answer 13

Lymington Hampshire

Mud flats cut by channels

Closer backshore = vegetated salt marsh

Question 14

geological structure

Answer 14

strata- different layers of rock exposed in a cliff

deformation- tilting and folding by tectonic activity

faulting- major fractures that have moved rocks from the original position

produces two types of coast (concordant and discordant)

Question 15

Concordant

Answer 15

different rock strata run parallel to coast

vary in terms of resistance

Lulworth cove:
hard portland limestone and fairly resistant Purbeck beds protect softer rocks landward (gault bed)
marine erosion has broken through resistant beds
rapidly eroded a cove behind
resistant chalk at the back of cove prevents erosion further inland

Question 16

Dalmatian coast, Adriatic sea (concordant)

Answer 16

geology is limestone
folded by tectonic activity into ANTICLINES (crests) and SYNCLINES (troughs)
lower synclines and upstanding anticline basins drowned by sea level rise
create long narrow islands in lines offshore

Question 17

Haff coastlines (concordant)

Answer 17

the southern edge of the Baltic sea
long sediment ridges topped by sand dunes run parallel to the coast just offshore
creates lagoons between ridges and shoreline

Question 18

Discordant

Answer 18

less resistant is eroded to form a bay
resistant geology remains as headlands

west cork Ireland
rock strata meet coast at 90 in parallel bands
especially resistant areas remain as detached islands, Clear Island

Question 19

wave refraction

Answer 19

process causing wave crests to become curved as they approach a coastline

Question 20

cliff profile

Answer 20

the height and angle of a cliff face, plus its features such as wave-cut notches or changes in slope angle

Question 21

cliff profiles influenced by

Answer 21

GEOLOGY, two characteristics;

resistance to erosion of the rock
dip of rock strata in relation to the coastline

Question 22

horizontal dip

Answer 22

near vertical/vertical profile with notches reflecting strata that are more easily eroded

Question 23

seaward dip high angle

Answer 23

sloping, low angle profile with one rock layer facing the sea, vulnerable to rock slides down the dip slope

Question 24

seaward dip low angle

Answer 24

profile may exceed 90 degrees producing areas of overhanging rock, very vulnerable to rock falls

Question 25

landward dip

Answer 25

steep profiles on 70-80 degrees and producing a very stable cliff with reduced rock fall

Question 26

geological features influence cliff profiles and rates of erosion

Answer 26

faults- either side of fault line, rocks are often heavily fractured and broken and these weaknesses are exploited by marine erosion joints- occur in most rocks. often in regular patterns, dividing rock strata up into blocks with a regular shape fissures- much smaller cracks in rocks, often only few cm or mm long folded rocks- often heavily fissured and jointed, easily eroded

Question 27

micro-features

Answer 27

small-scale coastal features such as caves and wave-cut notches which form part of a cliff profile

Question 28

igneous rock

Answer 28

``` granite(few joints so limited weaknesses) basalt very slow (less than 0.1cm per yr) igneous= crystalline and the interlocking crystals make for strong, hard erosion resistant ```

Question 29

metamorphic rock

Answer 29

slate marble slow (0.1-0.3cm yr) crystalline metamorphic are resistant to erosion foliation(all crystals are orientated in one direction= weakness) often folded and heavily fractures=weakness

Question 30

sedimentary rock

Answer 30

``` sandstone limestone moderate to fast (0.5-10cm yr) most are clastic and eroded fastest geologically young=weaker many bedding planes and fractures (shale) = most vulnerable ```

Question 31

unconsolidated

Answer 31

sediment that has not been cemented to form solid rock= LITHIFICATION

Question 32

erosion and weathering are influenced by

Answer 32

- how reactive minerals in rock are when exposed to chemical weathering - whether rock is clastic or crystaline - degree to which rocks have cracks, fractures and fissures

Question 33

clastic

Answer 33

sediment particles cemented together

Question 34

crystalline

Answer 34

made up of interlocking mineral crystals

Question 35

cliff profiles also be influenced by the permeability of strata

Answer 35

permeable allow water to flow through them | impermeable do not allow groundwater flow and includes clays/mudstones

Question 36

pore water pressure

Answer 36

internal force within cliffs, exerted by the mass of groundwater within permeable rocks

Question 37

vegetation stabilises coastal sediment in number of ways

Answer 37

- roots bind sediment particles together making them harder to erode - when submerged, plants provide protective layer so sediment surface is not directly exposed to moving water and erosion - plants protect sediment from erosion by wind, by reducing wind speed at surface by friction

Question 38

halophytes

Answer 38

salt tolerant

Question 39

xerophytes

Answer 39

drought tolerant

Question 40

plant succession

Answer 40

Changing structure of a plant community over time as an area of initially bare sediment is colonised pioneer plants begin to grow on bare sand forms first stage each stage is called a seral stage end result is called climatic climax community (sand dune ecosystems(psammosere) and salt marsh(halosere))

Question 41

coastal

Answer 41

1. colonisation of embryo dunes by pioneer species: stabilise the mobile sand by root systems reduce wind speed= more sand deposited add dead organic matter to sand, beginning process of soil formation

Question 42

embryo dunes

Answer 42

alter environment conditions from harsh, salty, mobile sand to one that plants can tolerate

Question 43

sand dune plant succession

Answer 43

``` sea EMBRYO AND FORE DUNES bare sand couch grass marram grass YELLOW DUNES marram and sedge grass creeping willow FIXED DUNES pine and birch WOODLAND ```

Question 44

successional development on bare mud deposited in estuaries

Answer 44

exposed at low tide but submerged at high ideal for development: -sheltered from strong waves, silt and mud can be deposited -rivers transport supply of sediment to river mouth and may be added to by sediment flowing into estuary at high tide