coasts

Question 1

4 examples of depositional landforms💓🏝️

Answer 1

beaches, sand dunes, spits, bars

Question 2

4 examples of erosional landforms🌴💞

Answer 2

headlands, bays, arches, stacks, stumps, wave-cut platforms

Question 3

example of discordant coast line?🌍

Answer 3

dorset

Question 4

sand dunes💞🦎
where are the mobile and fixed dunes in relation to the beach?
what 2 types of plants do sand dunes contain?

Answer 4

mobile dunes nearest the sea, fixed dunes near the back of the beach
xerophytes and halophytes

Question 5

what are xerophytes?
what are halophytes?
🏝️🌴🌿💐🪷🌱

Answer 5

xerophytes: needs very little water, can withstand periods of dry temperature
halophytes: can withstand high concentrations of salt from saltwater

Question 6

constructive waves🌊💓

Answer 6

-low and long
-stronger swash
-forms gently sloping beaches
-beach gains material
-found in sheltered bays
-more common in summer

Question 7

destructive waves🌊💓

Answer 7

-steep and high
-backwash more powerful
-high frequency
-steep beach
-removes material from beach
-more common in winter

Question 8

what is corrosion?🫧🩷

Answer 8

when there is a chemical reaction between the seawater and susceptible rocks like limestone
(the acids in seawater dissolve alkaline rocks)

Question 9

what is hydraulic action?🎀

Answer 9

when water is being compressed into the cracks of the rocks repeatedly, air is trapped under high pressure in the cracks. this leads to the breakdown of the cliff

Question 10

what is abrasion?😸😼

Answer 10

where pieces of rock are picked up by waves and hit against the bed, beach or cliffs. this wears them away over time

Question 11

what is attrition?🛤️

Answer 11

when rock particles carried in the sea are hit against one another, causing a reduced particle size making them more rounded

Question 12

what is mechanical weathering?
what is chemical weathering?
💐

Answer 12

mechanical- process of breaking big rocks into smaller ones
chemical- changes that some substances can cause on the surface of the rock

Question 13

at holderness, weak boulder clay has been eroded by ___ metres in a century
⛴️💞

Answer 13

120

Question 14

are beach profiles steeper in summer or winter? ❄️🏝️

Answer 14

summer

Question 15

how are berms created by constructive waves?🌊🌊🌊

Answer 15

the swash deposits larger material at the top of the beach.
as the berm builds, the backwash becomes weaker so beach material becomes smaller towards the shoreline.

Question 16

why are berms eroded in winter by destructive waves?🎀

Answer 16

the strong backwash drags sediment back

Question 17

how is a wave cut notch formed?⭐️

Answer 17

when waves break against the foot of a cliff, erosion is concentrated close to the high tide line, creating a notch which begins to undercut the cliff.

Question 18

how is a wave cut platform formed?🌫️☁️

Answer 18

as the notch grows, the rock above becomes unstable and eventually the cliff above collapsed.
as the processes repeat, the notch migrates inland leaving behind a platform

Question 19

in longshore drift, which direction do the swash and backwash carry material?💞

Answer 19

swash carried material up the beach, in the direction of the prevailing wind
backwash carried material directly down

Question 20

what are the 4 methods of marine transport? 🪼🐠🐟🐬🐳🐋💞

Answer 20

traction
saltation
suspension
solution

Question 21

caves, arches, stacks and stumps formation???🩷

Answer 21

cave: faults are exploited by hydraulic action and abrasion
arch: cave is eroded through
stack: top of arch becomes unstable (often by biological weathering) leaving a pillar
stump: when the stack is eroded further and collapses

Question 22

how is a spit formed?🌷

Answer 22

sediment is moved by longshore drift
if the coastline changes direction, sediment will build up
current from river stops it extending all the way
wave refraction carries material into sheltered water to form a recurved spit
salt marsh occurs where finer sediment is deposited (between the spit and the coastline) they’re salt tolerant

Question 23

what’s eustatic sea change?🐬

Answer 23

when ice on land melts and returns to the ocean, increasing the volume of water in the sea.
usually accompanied by thermal changes which melts land ice

Question 24

what is isostatic sea change?🪼

Answer 24

the downward movement of land, causing localised sea level rise.
land can be stressed down from post-glacial adjustments and accretion

Question 25

what is accretion?🌺

Answer 25

accumulation of layers pushing down on earth (leads to isostatic change)

Question 26

how does coastal flooding affect the maldives?🏝️💞🌊

Answer 26

it causes a loss of tourism, beaches, soil and freshwater whilst destroying the fishing industry and damaging homes

Question 27

how might climate change lead to coastal flooding?🌸

Answer 27

due do the increase in extreme weather, the frequency and magnitude of storms can contribute to sea level rise

Question 28

how many metres does the holderness coastline erode each year?🌿
why is this?💞

Answer 28

1.8m
due to the easily erodible rock types and narrow beaches

Question 29

2 examples of sub aerial processes?🦎🌱🦎🌱🦎🌱🦎🌱🦎🌱🦎🌱🦎🌱🦎🌱🦎

Answer 29

weathering and mass movement

Question 30

impacts of 2007 bangladesh flooding?💐
why do they suffer from this?

Answer 30

-9 million homeless and 1000 dead from drowning and water borne diseases
-due to occurrences of cyclones and heavy monsoon rains. also deforestation and low-lying land

Question 31

what is a rock fall?🌦️

Answer 31

when strong, steep rock faces are exposed to mechanical weathering (eg freeze thaw).
material falls and forms scree at base

Question 32

what is a landslide?❄️

Answer 32

rocks with parallel bedding planes to the cliff surface are susceptible to land slides.
an increase in the amount of water can reduce friction, causing landslides.

Question 33

what’s slumping?💞💞💞

Answer 33

occurs on moderate to steep slopes
there is rotational slip
common when softer materials overlie more resistant rock
causes terraced cliff profiles

Question 34

how high do the kiribati islands lie above sea level?☁️

Answer 34

1m or less

Question 35

how do groynes, sea walls and rock armour work?💓

Answer 35

groynes: low wall built out to sea. prevents movement of beach material. builds up the beach.
sea walls: curved so reflect wave energy. protective. high maintenance. make a promenade.
rock armour: rocks absorb wave energy. easy to construct and maintain.

Question 36

how does beach nourishment and dune stabilisation work?🏙️🌃🏙️🌃🏙️

Answer 36

beach nourishment: sand added to beach, makes it wider, increasing distance wave travels before reaching the cliff. reduces its energy and erosive power. natural.
dune stabilisation: widens the dunes to dissipate wave energy by replanting marram grass. makes habitats.

Question 37

what’s an emergent coastline?😽

Answer 37

when sea level falls and exposes land previously covered by sea

Question 38

what’s a submergent coastline?💜
what are 3 things. that form from it?

Answer 38

when a rise in sea level flood the coast
-rias, dalmatian coasts and fjords

Question 39

case studies?🦎🌴🌷

Answer 39

-holderness (hornsea, mappleton, spurn)
-bangladesh, maldives

Question 40

name 4 marine erosional processes🔮

Answer 40

hydraulic action
corrosion
abrasion
attrition

Question 41

3 physical factors that increase erosion🐲

Answer 41

less resistant rock
winter
geological weaknesses

Question 42

4 factors that influence mass movement💗

Answer 42

gradient/ steepness of a slope
water
human activity
vegetation (help bind soil)