CL - depositional landforms 1-18p

Question 1

examples of inputs in a system

Answer 1

1. energy from:
   - waves
   - wind
   - tides
   - currents
2. sediment
3. geology of coastline
4. sea level change

Question 2

examples of components of a system

Answer 2

erosional and depositional landforms and landscapes

Question 3

examples of outputs in a system

Answer 3

• dissipation of wave energy
• accumulation of sediment above the tidal limit
• sediment removed beyond local sediment cells

Question 4

what are sediment cells

Answer 4

• movement of sediment that occurs in distinct areas called cells
• a stretch along the coastline where sand is largely self-contained
• closed system
• although there are inputs and outputs of energy, the sediment stays largely within the cell

Question 5

whats a sub - cell

Answer 5

• if part of a larger cell they are called sub cells
  flamborough head-humber estuary sub cell is part of the
  flmborough head the wash cell

Question 6

parts of a wave and what is it

Answer 6

undulations on the surface of the sea driven by wind
- fetch - distance the waves travels over the sea
- height - difference between the CREST (highest part) and the TROUGH (lowest)
- length - distance between crests
- frequency - number of waves per min

Question 7

how waves are formed and the process

Answer 7

• wave enters shallow water
• friction with the seabed increases causing the wave to slow down
• the wavelength decreases and successive waves start to bunch up
• the wave increases in height
• then plunges or breaks onto the shoreline

Question 8

3 types of breaking waves

Answer 8

spilling - steep waves on gently sloping beaches
plunging - steep waves on steep beaches
surging - low angle waves on steep beaches

Question 9

constructive waves

Answer 9

• low
• long length (up to 100m)
• low frequency (6-8 per min)
• the strong swash loses momentum and volume leading to a weak backwash and low sediment movement off the beach
• higher swash energy than backwash
• material is slowly and gradually moved up the beach forming BERMS

Question 10

destructive waves

Answer 10

• high
• steep
• high frequency (10-14 per min)
• powerful backwash. where sediment is pulled away from the beach
• backwash has more energy than swash
• very little material is moved up the beach - forming STORM BEACHES

Question 11

what is wave refraction

Answer 11

• when waves break on an irregularly shaped coastline

Question 12

an example of wave refraction - headland separating two bays

Answer 12

• waves drag in the shallow water approaching a headland
• wave becomes high steep and short
• the part of the wave in deeper water moves forward at a faster pace causing the wave to bend
• the low energy wave spills into the bays as most of the wave energy is concentrated on the headland

Question 13

tidal cycles

Answer 13

the periodic rise and fall of the sea surface is produced by the gravitational pull of the moon and to a lesser extent the sun
- the moon pulls water towards it creating high tide
- there is a compensating ‘bulge’ on the opposite side of the earth
- at areas between the two bulges - low tide occurs
- when the moon and sun are at right angles to each other the gravitational pull is weak - NEAP TIDE

Question 14

tidal range

Answer 14

influences where wave action occurs and weathering processes

Question 15

lithology and examples

Answer 15

• chemical and physical structure of rocks
• weak rock like clay erode faster than resistant rock such as basalt

Question 16

concordant coastline

Answer 16

• bands of rock lie PARALLEL to the coastline
• the hard rock lies on the seaward side and bays develop when a weakness is eroded landward

Question 17

discordant coastline

Answer 17

• bands of rock lie perpendicular to the coastline
• weaker rock erodes faster forming a bay and the hard rock is left forming a headland

Question 18

landward and seaward dipping rocks

Answer 18

landward - lead to steep cliffs
seaward - cliffs follow the angle of dip

Question 19

long shore drift

Answer 19

waves approaching te shoreline at angle creating a zig zag pattern
creates a current of water running parallel to the shoreline

Question 20

rip currents

Answer 20

• strong currents moving away from the shoreline due to a build-up of sea water and energy along the coastline
• creates beach features such as cusps

Question 21

upwelling

Answer 21

• global pattern of currents circulating in the oceans can cause deep water to move towards the surface which displaces the warmer water

Question 22

global pattern of ocean currents

Answer 22

• the global pattern of ocean currents is generated by the earths rotation
• warm ocean currents transfer heat from low latitudes to high latitudes and cold ocean currents from high to low latitudes

Question 23

positive sediment budget

Answer 23

more material added than removed - shoreline builds to the sea

Question 24

negative sediment budget

Answer 24

more material removed than added - shoreline recedes landwards

Question 25

4 physical weathering processes

Answer 25

- freeze thaw - pressure release - thermal expansion - salt crystalisation

Question 26

freeze-thaw weathering

Answer 26

water enters cracks and joints and expands by 10% when it freezes. this exerts pressure on the rock causing it to split or parts break off

Question 27

pressure release

Answer 27

a type of physical weathering caused when rocks that are under a great amount of pressure no longer have to bear a heavy load, causing expansion and fracturing.

Question 28

thermal expansion

Answer 28

rocks expand when heated and contract when cooled. when this happens lots layers may crack and flake off - insolation weathering

Question 29

salt crystalisation

Answer 29

solutions of salt seep into pore spaces in porous rocks. then the salt precipitates - forming crystals. the growth of these crystals causes the rock to disintegrate

Question 30

5 types of chemical weathering

Answer 30

- oxidation - carbonation - solution - hydrolysis - hydration

Question 31

oxidation

Answer 31

minerals in rocks react with oxygen in air or water

Question 32

carbonation

Answer 32

- rainwater combines with dissolved carbon dioxide from the atmosphere to produce a weak carbonic acid - this reacts with calcium carbonate in rocks such as limestone to produce calcium bicarbonate - soluble - this is reversible

Question 33

solution

Answer 33

- any process where a mineral dissolves in water - some salts are soluble in water - other minerals eg iron are only soluble in very acidic solutions

Question 34

hydrolysis

Answer 34

- chemical reaction between rock minerals and water

Question 35

hydration

Answer 35

water molecules added to rock minerals create new minerals of a larger volume - this causes surface flaking in rocks

Question 36

2 types of biological weathering

Answer 36

- tree roots - organic acids

Question 37

tree roots

Answer 37

tree roots growing into cracks or joints in rocks and exert outward pressure.

Question 38

organic acids

Answer 38

- organic acids are produced during decomposition of plant and animal litter - this causes soil water to become more acidic and react with minerlas in a process called chelation

Question 39

5 processes of mass movement

Answer 39

landslides rockfalls mud flows rotational slip/ slumping soil creep

Question 40

landslides

Answer 40

cliffs made of softer rock slip when lubricated by rainfall

Question 41

rockfalls

Answer 41

rocks undercut by the sea or slopes affected by mechanical weathering

Question 42

mud flows

Answer 42

heavy rain causes fine material to move downhill

Question 43

rotational slip/ slumping

Answer 43

where softer material overlies resistant material and excessive lubricant takes place

Question 44

soil creep

Answer 44

very slow movement of soil particles downslope

Question 45

list of erosional landforms

Answer 45

headlands and bays cliffs wave cut platforms caves, stacks, stumps, arches blowholes

Question 46

list of depositional landforms

Answer 46

beaches spits bars tombolos deltas sand dunes