1
Q
list the three sections of the littoral zone
A
- backshore
- nearshore
- offshore
2
Q
describe a rocky coast environment
A
- resistant to erosive forces of sea wind and rain
- often a high energy environment
- both high and low relief
3
Q
describe a coastal plain landscape
A
- found in low relief areas
- result from supply of sediment different terrestrial and offshore sources
- often a low energy environment
4
Q
what is responsible for the formation of concordant/discordant coastlines?
A
geological structure
5
Q
how is a discordant coastline formed?
A
- layers of rock perpendicular to the sea expose soft rock which is eroded faster than the hard rock
- this differential erosion causes headlands of hard rock and bays where soft rock has been eroded
6
Q
give an example of a discordant coastline
A
swanage bay, dorset
7
Q
how is a concordant coastline formed?
A
- layers of rock are parallel to the sea
- hard rock forms a protective layer in front of soft rock and prevents erosion
8
Q
how are coves formed?
A
when the hard rock layer at concordant coastlines is breached and the softer rock behind it is eroded e.g. lulworth cove
9
Q
where and how to Dalmatian coasts form?
A
at concordant coastlines
- rise in sea level floods valleys but the top of ridges remain visible above the water
10
Q
where and how do Haff coasts form?
A
form on low-energy, concordant coastlines where sediment (sand/gravel) is deposited by constructive waves, creating long, narrow offshore bars or spits parallel to the shore, often after glacial melt
11
Q
which 5 geological structures have an important influence of coastal morphology, erosion rates, cliff profile formation, and the occurrence of micro features?
A
bedding planes, jointing, dips, faults, and folding
12
Q
what do bedding planes, jointing, dips, faults, and folding have an important influence on?
A
coastal morphology, erosion rates, cliff profile formation, and the occurrence of micro features
13
Q
which three factors are determined by rock structure/lithology?
A
- rock harness
- permeability
- physical make up of rocks
14
Q
how is rock hardness determined by rock structure/lithology?
A
igneous and metamorphic rock are harder due to their heating and compression during their formation , meaning the are more resistant to erosion
- soft socks e.g. sedimentary rock, erode more easily
15
Q
how is rock permeability determined by rock structure/lithology?
A
- determined by structures
- the incidence of pores, fissures, cracks, or joints creates gaps in the rock for water to seep in
16
Q
how is the physical make up of rocks determined by rock structure/lithology?
A
physical make up refers to the amount of bedding planes, joints, and faults
- a higher density of these = weaker rocks
- this creates higher rates of erosion
17
Q
what are the three positions bedding planes can be in and what do each mean for the coast/erosion?
A
- horizontal -> forms small overhangs of more resistant rock
- dipped towards the sea –> forms a gently sloping cliff face which is more vulnerable/exposed to erosion
- sloping up away from the sea –> steep stable cliff is produced
18
Q
give an example of igneous rock
A
basalt
granite
19
Q
give an example of sedimentary rock
A
sandstone
limestone
20
Q
give an example of metamorphic rock
A
marble
21
Q
why are some rocks types more resistant than others?
A
- mineral composition of the rock + therefore hardness
- chemical composition of the rock
- internal rock structure
22
Q
how do minerals determine the resistance of a rock type?
A
- how tightly the minerals are packed together: unconsolidated rock the minerals are loosely packed allowing water to attach to them. this makes them unstable and less resistant
- consolidated rock = minerals are tightly packed -> more stable + more resistant
- type of mineral: some minerals are very hard e.g. feldspar, others are softer and more resistant e.g. calcite (found in chalk and limestone)
23
Q
how does chemical rock composition determine the resistance of rock?
A
chemicals in the rock react differently with water + oxygen
- feldspar eats with water to form a weaker mineral kaolinite through hydrolysis
- calcium and magnesium oxidise to form iron oxide which causes rock decomposition
24
Q
how does the internal structure of rocks determine their resistance?
A
more layers in the rock = more bedding planes= more joints between bedding planes to be exploited by erosional processes
25
give an example of an unconsolidated material
boulder clay
26
other than parallel and perpendicular layer so frock, what else can cause complex cliff profiles in a similar way?
layers of impermeable/permeable rock, and layers of resistant/less resistant rock
27
which scale organises minerals in order of harness?
the MOHS scale
28
how is vegetation important in coastline stability?
root systems bind sand and soil, preventing erosion, while its stems and leaves slow down wind and water (waves, currents, tides), forcing sediment to drop out and build up the shoreline
29
where is vegetation stability primarily found on coastlines?
salt marshes and sand dunes
30
what is a salt marsh?
low energy coastal wetlands developing in sheltered intertidal areas, often behinf spits, through the accumulation of fine sediment and vegetation succession
31
what are the two wave types?
constructive and destructive
32
describe constructive waves (time of year, sediment)
- usually in the summer
- deposit large amounts of sediment resulting in beach gain
- strong swash, weak backwash
- low, surging waves
33
describe destructive waves (time of year, sediment)
- usually in winter
- beach loss of sediment as it is taken from the beach to offshore creating bars
- short wavelength
- weak swash, strong backwash
- high, plunging waves
- can exert rip
34
describe the seasonal temporal change of beach morphology due to wave changes
- summer = sediment retuned by constructive waves: a berm is created by the deposition of sediment
- winter = more destructive eaves: berms are eroded and the sediment is transported offshore
35
hat happens to the backwash as a berm builds in height?
it weakens and can therefore move less material
36
what is hydraulic action and what features does it cause?
the sheer force of waves smashing against cliffs traps and compresses air in cracks, causing the rock to break apart as the pressure is explosively released, gradually widening cracks and dislodging material over time, contributing to features like caves, arches, and stumps
37
what is corrosion?
a chemical process where seawater's weak acids (like carbonic acid) dissolve minerals in rocks, especially limestone and chalk, weakening them for erosion
38
what is abrasion and what features does it?
waves hurl sand, pebbles, and rocks against cliffs, grinding and chipping away at the rock surface like sandpaper, smoothing it over time and forming features like wave-cut platforms, caves, and arche
39
what is attrition?
rocks and pebbles carried by waves smash into each other, causing them to break down, become smaller, smoother, and rounder as they collide, gradually turning into sand and shingle
40
what is a wave cut notch and how is it formed?
a curved indentation or hollow carved into the base of a sea cliff, typically between high and low tide marks, formed by wave erosion (hydraulic action, abrasion, corrosion) that undercuts the rock, causing the unsupported cliff above to eventually collapse, leading to cliff retreat and leaving a flat wave-cut platform behind as the process repeats
41
what is a wave cut platform and how is it formed?
a flat, gently sloping rocky surface at the base of a cliff, formed by continuous wave erosion that undercuts the cliff, causing it to retreat inland, leaving the platform exposed at low tide as the debris is carried away
42
how are cliffs formed?
formed primarily by erosion and weathering that wears away softer rock, leaving harder, more resistant rock to form the steep drop
43
briefly explain the cave, stack, stump sequence
waves exploit weaknesses (cracks) to form caves, which erode through to form an arch; the arch's roof collapses, leaving a free-standing stack; and further erosion undercuts the stack until it collapses into a low, submerged stump,
44
how is sediment transportation influenced by the angle of wave attack?
- The angle of wave attack is the primary driver of longshore drift
- waves hitting at an angle (swash) carry material up the beach, and gravity pulls it back down perpendicular (backwash), moving sediment sideways along the coast, creating features like spits
45
what is a tombolo and how is it formed?
a sandy or shingle bar that connects an island to the mainland or another island, forming a "tied island:
-- Longshore Drift: Waves hit the coast at an angle, pushing sediment along the shore (swash) and pulling it back straight out (backwash), moving material down the coast.
-- Wave Refraction: When waves encounter an offshore island, they bend (refract) and wrap around it, causing them to slow down and lose energy on the sheltered side (the lee side).
-- Sediment Deposition: The sediment carried by longshore drift is then deposited in the calmer water behind the island, where wave energy is low.
-- Spit Formation: This deposition builds out from the mainland as a spit, extending towards the island.
-- Connection (Tombolo): The spit continues to grow until it connects the island to the mainland, forming a permanent or semi-permanent land bridge called a tombolo, often appearing as a causeway.
46
how is a cuspate foreland created?
an area of sheltered land formed by two joined spits:
-- Opposing Drift: Sediment (sand, shingle) is transported along the coast by longshore drift from two different directions.
-- Convergence: These currents meet at a point, often in a bay or across an open coast.
-- Deposition: As the currents lose energy, they deposit their sediment load.
-- Spit Formation: This deposition builds out into the sea as two spits, one from each direction.
-- Meeting & Growth: The spits grow towards each other, eventually meeting in the middle, forming a triangular or cusp-shaped barrier that extends seaward.
-- Stabilization: Vegetation can establish on the deposited material, helping to bind it and stabilize the landform
47
what landform can b created as a result of s curved spit?
a salt marsh due to the protected area behind the curve of the spit
48
in which two ways can an offshore bar be created?
1. Bar Formation: If the spit grows long enough to stretch across the entire bay, connecting to the other side, it becomes a barrier beach (or bar).
Lagoon Creation: This process traps seawater behind the barrier, forming a lagoon (like Slapton Ley in Devon).
2. sediment deposited by destructive waves offshore build up until they are visible above the water
49
explain the sediment cell concept
The sediment cell concept divides coastlines into distinct units where sediment (sand, shingle) is sourced, transported, and stored in a largely self-contained system, acting like a closed system bounded by natural barriers (headlands, estuaries)
50
how is sediment sourced?
erosion and weathering
51
what is a transfer in the sediment cell concept
Processes moving sediment, like longshore drift, currents, and wave action (swash/backwash).
52
what is a sink in the sediment cell concept
Areas where sediment accumulates, such as beaches, spits, bars, and offshore banks.
53
what is the sediment budget?
The balance between sediment inputs and outputs; if inputs fall, erosion increases.
54
give an example of a sediment cell
the wash sediment cell
55
where is the main source for the wash sediment cell?
cliffs of Norfolk --|> retreats 1m a year
56
give two other sources of sediment for the wash sediment cell
- erosion of holderness cliffs brings sediment by suspension
- 4 rivers discharge into the wash bringing fine sediment
57
how can coastlines be an example of a negative feedback system?
the maintenance of the sediment budget: when change is counteracted e.g. like storm erosion creating offshore bars that reduce wave energy, protecting the beach.
58
how can coastlines be an example of a positive feedback system?
destabilizes the system by amplifying changes, such as wind removing dune vegetation, leading to more wind erosion and further loss of sand until a new balance is reached
59
what are the three types of weathering?
- mechanical
- biological
- chemical
60
what is weathering?
the decay and disintegration of rock
61
explain what happens in biological weathering
breaks down rocks and minerals through the actions of living organisms like plants, animals, and microbes
- Roots grow into tiny rock fissures, expanding them as the roots get bigger, eventually breaking the rock apart
- Burrowing creatures
- Lichens, fungi, and bacteria release acids that dissolve rock minerals
62
explain what happens in mechanical weathering
the process of breaking rocks into smaller pieces (sediments) without changing their chemical makeup, driven by physical forces
- Freeze-Thaw (Frost Wedging): Water enters rock cracks, freezes, expands (by about 9%), and forces the crack wider
- salt water evaporating and creating salt crystals which widen cracks
- the wetting and drying of clay-rich rocks --> clay expands when wet
63
explain what happens in chemical weathering
breaks down rocks by changing their chemical composition
- Carbonation: Carbon dioxide in rainwater forms weak carbonic acid, which dissolves minerals like calcium carbonate in limestone and chalk
- Oxidation: Oxygen and water react with iron and other minerals in rocks, forming iron oxides (rust), weakening the rock
- Hydrolysis: Acidic rainwater chemically reacts with minerals (like feldspar), breaking them down and transforming them into clay minerals and other soluble substances.
64
what are the three forms of mass movement categorised as flows?
- soil creep
- solifluction
- mud flows
65
what are the two forms of mass movement categorised as slides?
- rock falls
- rock slides
66
what you of mass movement is categorised as a slump?
slumps
67
what is soil creep and how does it occur?
the slow downhill movement of individual soil particles due to gravity
68
what is solifluction and how does it occur?
when the surface layer of frozen ground thaws but the bottom layer des not, causing the top layer to flow over the frozen subsoil and rock beneath
69
what is a mud flow and how does it occur?
high amounts of water in the soil can reduce friction and cause mud to flow over underlying bedrock
70
what is a rock fall and how does it occur?
- occur on slopes over 40 degrees steep
- is a result of mechanical weathering
- broken away rock falls and from scree at the bottom of the cliff
71
what is a rock slide and how does it occur?
- slabs of rock slide over underlying rocks along a slip plane
72
what is a slump and how does it occur?
- a rotational movement
- occurs in saturated conditions
- common when softer materials overlie more resistant rock
73
what do slumps cause?
rotational scars
74
how are talus scree slopes formed?
the accumulation of broken rock fragments (debris) at the base of cliffs, primarily driven by weathering
75
how are terraced cliff profiles formed?
formed by rotational slumping
76
what does the term eustatic sea level change mean?
a global rise or fall in sea level caused by changes in the actual volume of water in the oceans, primarily due to climate shifts (melting ice sheets/glaciers adding water, or ice ages locking water away)
77
what does the term isostatic sea level change mean?
a local change in sea level caused by the land itself rising or falling relative to the sea, usually due to shifts in weight on the Earth's crust
78
what is isostatic subsidence?
when the weight of ice sheets during glacial periods causes the land beneath them to sink
79
what is isostatic recovery?
when ice sheets melt and their weight loss causes the land to rise again
80
where do emergent landforms form?
when sea levels fall or land rises
81
give two emergent coastline landforms
- raised beaches
- relic cliffs
82
give 3 submergent coastline landforms
- rias
- Dalmatian coasts
- fjords
83
what is a rias?
a sheltered winding inlet with irregular shorelines
- formed when original river channels are flooded
84
what are fjords?
when deep glacial troughs are flooded by a ruse in sea level
85
give an example of a Dalmatian coast
croatia
86
give an example of a fjord
Milford sound, New Zealand
87
how does global warming cause sea level rise?
melts glacial ice and ice caps
88
where is at risk from sea level rise due to climate change?
tuvalu - all of populations lives within 1km of the coast
- planned migration for its citizens, with Australia offering world-first climate visas under the "Falepili Union" treaty, allowing 280 Tuvaluans annually to resettle permanently,
- could be underwater by 2100
the Maldives
89
list 3 reason why climate change can alter coastlines
what are the consequences of these
- sea level rise
- increased storm intensity
- changes in wave climate -> increased frequency, height, energy + changes in direction
consequences:
- reshaping of beaches
- increased cliff retreat
- loss of natural defences like sand dunes
90
what does the term 'mass movement' mean?
the downhill, large-scale transfer of weathered material (rock, soil, mud) down a slope primarily due to gravity, often triggered or exacerbated by water (heavy rain), weathering (like freeze-thaw), and undercutting by erosion,
91
which short term factors influence rates of coastal recession?
- wind direction/fetch
- tides
92
which long term factors influence rates of coastal recession?
seasons
weather systems
storm occurrence
93
give an example of an area which is at risk of coastal flooding
Bangladesh
94
what are the human reasons behind banglashes' increased coastal flooding risk?
- most densely populated country at 169million in 2015
- deforestation + therefore soil erosion so the land absorbs less water
- irrigation farming = silted river channels, decreasing the water capacity
- global warming = snow melt and monsoon rainfall
- 2/3 of country lives less than 5m above sea level
- 60mill people in rural areas live below the poverty line
- many slums -> lack of access
- cannot afford recovery + prevention
- poorly built settlements
95
what are the physical reasons behind banglashes' increased coastal flooding risk?
- lies on the floodplains of three major rivers, including the Ganges
- 54 smaller rivers flow through th bay of bengal
- Himalayan snow melt
- march-may = violent thunder storms: 6m waves + 160km/h winds
96
give an example of a storm surge that occurred in your chosen area for coastal flooding risk
Cyclone Side, category 4, 2007
97
what where 2 short - term human impacts of your chosen storm surge
- contaminated drinking water
- over 700km of electricity lines damaged
98
what where 3 long - term human impacts of your chosen storm surge
- 1.5 million houses damaged
- over 8000km of roads damaged
- over 700,000 hectares of crops damaged
99
why is it important to measure the impacts of climate change?
the future risk it poses is uncertain, therefore we need mitigation and adaptive strategies ti combat it
100
what are 4 economic losses associated with coastal recession?
loss of:
- houses
- businesses
- agricultural land
- infrastructure
101
what are 3 social losses associated with coastal recession?
- relocation
- loss of livelihood
- decreasing amenity value (the pleasantness or attractiveness of a place decreases due to the risk/danger)
102
where can be used to show the economic and social loses associated with coastal recession?
the holderness coast
103
list the social losses due to coastal recession at the holderness coast
- over 2000 yers 4km has been lost to erosion, destroying 30 settlements
- ar risk houses loose their value leaving the owners with negative equity
104
list the economic losses due to coastal recession at the holderness coast
-farms loose valuable land - Around 80,000 m² of farmland is lost every year as the soft boulder clay erodes
- loss of house value - Some properties have lost up to 70% of their value.
- loss of 30 settlements
- easing ton gas terminal
105
what is the environmental loss due to coastal recession at the holderness coast
- reduced biodiversity as the local environment cannot support as many species due to a reduced sediment supply
106
what are the cons of hard engineering strategies?
- expensive
- directly alter physical processes and systems
107
where can be used to show to negative impacts of har engineering strategies?
Hornsea
108
what are the negative impacts of hard engineering strategies at Hornsea
groyns starve the downdraft beach, leaving it vulnerable to erosion
groins also cost around £5.1 million to construct for the whole coastline
- sea wall built in 1870 only lasted 6 years
109
give an example of how the `actions of different players can have unforeseen consequences
the east riding of Yorkshire council approved, and the UK gov. gave funding for the groins and rock armour used to protect the B1242 road at Hornsea --> however this accelerated erosion at Cowden and Skipsea
110
what 5 soft engineering strategies have been implemented along the Holderness coast?
- beach nourishment
- dune stabilisation/regeneration
- offshore reefs
- beach reprofiling
- cliff regrading and drainage
111
give 3 reasons for why coastal erosion is such a problem at Holderness
- deep sea floor gives waves to time to loose energy through friction before they slam into the coast
- currents circulate from the Atlantic Ocean into the North Sea, adding energy to waves + creates destructive waves
- low pressure systems and winter storms are intense over the north sea
112
give a geological reason why coastal erosion is such a problem at Holderness
mostly made of fine and non-resistant boulder clay which is easily eroded - also prone to wetting and drying, and freeze thaw weathering
- boulder clay is also prone to slumping
113
what was the direct impact of the groins at Honsea?
in the 1990s Mappleton lost nearly 4m of cliff each year
114
what are the benefits of soft engineering strategies?
they attempt to work with physical systems and processes, so are therefore less invasive and disruptive
115
what are the positives and negatives of beach nourishment?
cheap and easy, natural, tourists like a bigger beach
BUT
needs constant maintenance due to longshore drift
116
what are the positives and negatives of dune stabilisation/regeneration?
natural, provides habitat, cheap and sustainable
BUT
time consuming to plant marram grass, may upset people through lack of access to dunes
117
what are the positives and negatives of cliff regrading and drainage?
cost effective and can work on clay
BUT
causes cliff to retreat + draining can cause cliffs to dry out completely and collapse
118
what is cliff regrading and drainage?
regrading = reduces the angle of the cliff to help stabilise it
drainage = removes water to prevent landslides an slumps
119
what are the negatives of the withernsea sea wall?
- promenade is smaller
- waves break noisier
- view is restricted
- some tourists find the riprap ugly
120
what defences were erected at Mappleton? what was the impact?
two £2million rock groins
- starved Cowden 3km down the coast of sediment - increased erosion from 2.5-3.8m a year between 1991 and 2007
121
what are the for options for coastal action?
- hold the line
- advance the line
- managed retreat
- do nothing
122
what is the aim of sustainable management?
to allow the coastline to cope with future threats
123
where can sustainable management cause conflict? give an example
Khulna in Bangladesh is a river port which is prone to flooding - 2014 = Bangladesh planned to build 600km of embankments in the at risk Sundarbands delta region using $400 million from the Wold Bank -> a British geomorphologist said this would put millions of lives at risk
- local people and the Bangladeshi government dont want to give up land despite the risk
124
how has sustainable management been implemented in Sri Lanka?
the plantation of coastal mangroves - restored 500 hectares of mangrove since 2015.
125
what is the aim of Integrated Coastal Zone Management?
aims to balance coastline protection and its people and economy utilisation
126
what does the ICZM do?
- Assesses of Coastal Environments
- Effectively Engages Stakeholders e.g. NGOs, local councils
- decision making is based off assessments and stakeholder inputs
127
what is a community benefit from engaging in ICZM strategies?
Communities that engage in ICZM often enhance their capacity to recover from disasters by leveraging local knowledge and resources.
128
how is collaboration key in ICZM?
creates a supportive network for sharing knowledge, resources, and best practices. By forging these connections, stakeholders can pool their strengths, leading to innovative solutions that benefit both people and the environment.
129
what two assessments are used as part of the management decision making process?
- Cost benefit analysis
- environmental impact assessment
130
what is a cost benefit analysis?
a decision-making tool to evaluate projects (like coastal defences) by comparing total monetized costs (tangible, intangible) against total benefits (tangible, intangible) over time
GEOGRAPHY
flashcards
Decks in class (53)
# Cards
-
TECTONICS88
-
Tectonics - Typhoon Haiyan13
-
Tectonics - Haiti 20108
-
Tectonics - Monserrat eruption 19956
-
Tectonics - Mount St. Helens eruption6
-
Tectonics - 2004 Asian Tsunami9
-
Tectonics - Christchurch earthquake 20114
-
Tectonics - Japan Tsunami9
-
COASTS130
-
GLOBALISATION112
-
Globalisation - Disneys Globalisation7
-
Globalisation Struggling to Globalise - Zambia11
-
Globalisation Switzerland - a switched on country4
-
Globalisation - Deindustrialisation in Detroit8
-
Globalisation - Deindustrialisation in Leicester4
-
Globalisation - Mumbai8
-
Globalisation - Cultural diffusion in Cuba4
-
Globalisation - cultural erosion - Bougainville7
-
Globalisation - Bangladesh - negative impacts of globalisation4
-
Globalisation - tonnes transition town5
-
Globalisation - controlling globalisation5
-
REGENERATION169
-
Regeneration - High Wycombe40
-
Regeneration - Tottenham11
-
Regeneration - HS2 Railway and Heathrow13
-
Regeneration - the Rustbelt USA10
-
Regeneration - London Docklands15
-
Regeneration - Grampound Cornwall - engagement5
-
Regeneration - Plymouth - urban rebranding7
-
Regeneration - Cornwall - rural rebranding7
-
WATER - Yukon River3
-
WATER - Amazon River4
-
WATER - Indus River2
-
WATER- Drought - The Sahel11
-
WATER - Drought - California10
-
WATER - Finite water resources - California18
-
WATER - privatisation of water - Cochabamba4
-
WATER - positive/negative impacts of water privatisation12
-
WATER - Tensions over the Nile15
-
WATER - water transfers in China8
-
WATER - sustainable use of water - Singapore33
-
WATER - impacts of drought on wetland and forest ecosystems12
-
WATER179
-
Superpowers - Players in international decision making44
-
SUPERPOWERS - Examples of hard and soft power9
-
SUPERPOWERS327
-
MIGRATION - contested borders55
-
Migration - migration in China11
-
MIGRATION + EQ181
-
SOVREIGNITY + EQ2210
-
IMPACT OF IGOs EQ3168
-
CARBON506
-
Important international players0
