Hazards Flashcards

(84 cards)

1
Q

What is a geophysical hazard?

A

-linked to the movement of earths tectonic plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Examples of geophysical hazards

A

-earthquakes
-volcanoes
-avalanches
-tsunami

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are Atmospheric hazards?

A

Linked to atmoshperic weather and climate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Examples of atmospheric hazards

A

-heatwaves
-extreme weather
-drought
-hurricane
-tropical storm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are hydrological hazards?

A

Linked to water and water logging of the land

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Examples of biological hazards

A

-covid
-wildfire

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is risk?

A

The exposure of people to a hazardous event presenting a potential threat to themselves, their possessions and the built environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why do people put themselves at risk?

A

-cost/ benefit
-lack of alternatives
-changing level of risk
-hazards are unpredictable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the costs/ benefits of living nest a hazard ?

A

Due to social, political, economic and cultural people can’t simply uproot themselves from one place and move to another, giving up their home, land and employment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why are there a lack of alternatives?

A

-there are many hazardous areas that offer advantages that in people’s minds outweigh the risk that they are taking living in that past
-in Californian cities people see that the advantages outweigh the disadvantages of living in the earthquake prone area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why is there a changing level of risk with hazards?

A

-Places that were once’s relatively safe have become more of a risk.
-deforestation in the Himalayas, for example, could result in more flooding from monsoon rains leading to a greater risk of landslides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is vulnerability?

A

-the potential for loss
-since losses vary geographically over time among different social groups
-vulnerability therefore varies over time and soace

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

are some people more vulnerable than others?

A

-people who experience a greater disparity in wealth are more vulnerable to a hazard as they experience a limited lack of resources that could be used in prevention of reducing the risks by doing things such as building earthquake proof buildings in a triangular shape.
-those less wealthy are Alamo more vulnerable after the event has taken place as they rely heavily on financial aid and resources abroad.
-LICS lack educated people in industries such as healthcare

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is perception?

A

The way in which something is regarded understood or interpreted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is fatalism?

A

-hazards are natural events that are part of living in that area
-some communities believe it’s gods will
-losses are accepted as inevitable and people remain where they are

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is adaptation ?

A

Anticipating the adverse effects and taking appropriate action to prevent or minimise damage they can cause.
-take advantage of opportunities that may arise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is fear ?

A

-the perception of the hazard is such that people feel so vulnerable to an event that they are no longer able to face living in the area and move away to regions perceived as to be unaffected by the hazard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is resilience?

A
  • determination of strength of character of community to pull through and counteract the disastrous events that could have human consequences
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is integrated risk management?

A

-set of processes/ practices that allow organisations to properly identify, mitigate and manage risk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is prediction ?

A

-estimating that a specific thing will happen in the future or will be a consequence of something

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is prevention?

A

-the methods we can put in place as humans to prevent a hazard entirely or some of the negative impacts it might have

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is protection?

A

-the pre-empt method put in place to reduce the risk of hazard when it does inevitability arrive such as boarding up windows and building up earthquake buildings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the first stage of the hazard management cycle?

A

Preparedness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are examples of preparedness?

A

-education and raising public awareness
-knowing what to do in the immediate aftermath to speed up recovery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the second stage of the hazard management?
Responses
26
What are some examples of responses?
-speed of responses will depend on the effectiveness of the emergency plan put in place -search and rescue teams -damage assessments
27
What is the third stage of the hazard management cycle?
Recovery
28
What are examples of recovery?
-restoring the affected area to somewhere near normality -short one -> restore services -long term -> construction to pre event levels
29
What is the last stage of the hazard management cycle?
Prevention/ mitigation
30
Example of mitigation
-actions aimed at reducing the severity of the event and lessening its impacts -building design -insurance
31
What does the park model include?
-pre disaster -relief -rehabilitation -reconstruction -return to normal
32
What does relief include?
-hours and days after the event -search, rescue, care
33
What does rehabilitation include ?
-days and weeks -temporary housing and services
34
What does reconstruction include?
-weeks and years -permenant rebuilding -HIC will see an improvement QOL
35
What did ortelius suggest?
-Africa and North America look like they have been torn apart -he thought this was by floods and earthquakes
36
What did we get suggest?
-concept of continental drift after studying fossils and rock types on each side of the Atlantic Ocean
37
What did Marie Tharp suggest?
-mid ocean ridges were rift valleys formed by plate motion.
38
What did Harry Hess suggest?
-was credited for wegners and Tharp a theory or tectonic movement and continental drift -lacked geophysical evidence
39
What is paleomagnetism ?
-evidence of the earths magnetic field being stored within rocks -at the time of fossil formation the magnetic mineral with them align themselves with the magnetic field -the magnetic field reverses around ever 400,000 years
40
How does paleomagnetism support the idea of seafood spreading or plates moving apart
Reversals are recorded in rocks on either side of the constrictive plate margin on the mid Atlantic and the symmetry in this magnetic striping provides evidences the plates are moving apart
41
What is the expanding earth theory?
-oceans are spreading so they must be getting bigger so the earth must be getting bigger with it -failed to consider deep ocean trenches where the sea floor is being pulled into the mantle and then destroyed
42
Why is radioactive decay key for plate movement?
-generates exceptional temperatures in the core -hot spots around the core heat the lower mantle creating convection currents -rise to the surface before spreading in the asthenosphere, then cooling and sinking again
43
What is ridge push ?
Molten magmas rises at the mid oceanic ridge, heating the rocks around and at the ridge the expand and become elevated above the sea floor producing a slope. As the newly formed rock ages it cools and becomes more dense then gravity caused this older lithosphere to slide away over the asthenosphere
44
What is slab pull?
-older denser oceanic lithosphere plates sink into the mantle at subduction zones as the gravity is acting on these plates they pull the newer less dense continental plates into the mantle with them when the plates subduct this pulls other plates apart causing sea floor spread
45
What happens at constructive plate margins?
-form chains of submarine mountains that extend across the ocean floor. -along these “spines” of mountains are breaks called transform faults which cut across the ridges- these faults occur at a right angle to the plate boundary -the middle of the ridge is a deep rift valley which are widened by magma rising from the asthenosphere and solidifying to form new crust
46
What type of earthquake form at a constructive plate margin?
-faults widen at separate fates, causing earthquakes with a shallow focus releasing the tension
47
What type of volcanoes form at a constructive plate margin?
-volcanic eruptions along the ridge build up submarine volcanoes, over time they all grow to rise above sea level forming volcanic island
48
What is a rift valley?
-formed when the lithosphere stretches causing it to fracture into sets of parallel faults -the land in between these faults collapses into deep wide valleys which are separated by upright rocks land called horsts
49
What are the stages of the hazard management cycle?
1)prevention 2)preparedness 3)Crisis 4)response 5)recovery
50
What is the park model?
Plots the quality of life after a natural disaster against the time after it’s occurred
51
What are the 4 phases of the park model?
Pre-disaster Relief Rehabilitation Reconstruction
52
Examples of what occurs in relief stage?
-search and rescue -care This will change in speed and effectiveness in HIC vs LIC
53
What happens during rehabilitation phase?
Temporary housing Services
54
What happens during reconstruction phase?
Perminant rebuilding
55
Advantages of park model?
-considers wide range of factors that would influence a hazard -easy to understand -widely used
56
Disadvantages of the park model?
-lack of context -simplistic -> assumes response is a linear process -doesn’t consider spatial variation
57
Similarities in HMC and TPM?
-both involve proactive stages of hazard management (mitigation and preparation) and reactive stages (response and recovery) -both optimistic -both don’t take into account economic status
58
Differences in HMC and TPM?
-PM-> lines HMC-> non linear -HMC more generic -PM illustrates how QOL can be impacted by hazard
59
Example of constructive plate margin?
Eurasian and North American
60
Example of destructive plate margin?
Pacific and North American plate
61
Example of conservative plate margin?
Pacific and North American (san Andrea’s fault)
62
What can form at constructive plate margin?
Sea floor spread Ocean ridges -> oceanic Rift valley-> continental and continent
63
What can form a destructive plate margin?
Subduction (oceanic and continental) : -ocean trench -island arc -Benidorm zone -subduction zone -composite volcano Collision (continental and continental) -earthquakes -fold mountains eg Himalayas
64
What forms at a conservative plate margin?
Earthquakes
65
What are hot spots?
-radioactive decay with the earth’s core -if it’s concentrated at one point hot spots form in asthenosphere -if it remains stationary the plate above it moves forming a chain of active then extinct volcanoes
66
What are magma plumes ?
-hot spots heat lower mantle -create localised thermal currents where magmas rises vertically
67
What is continental crust made out of?
-silica and aluminium
68
What is oceanic crust made out of?
Silica and magnesium
69
What are the parts of the earth in order
Lithosphere Asthenosphere Mantle Outer core Inner core
70
Describe asthenosphere?
100-700km thick
71
Describe the mantle ?
2900km thick Thick liquid Denser w depth
72
Describe the core
5000 degrees Iron and nickel Primeval
73
Describe the inner core
Solid Iron-nickel alloy
74
Describe the outer core
Semi-liquid Iron
75
Describe the plate tectonics theory
-tomography-> found weak convection currents aren’t strong enough to move plates -asthenosphere is too plastic to have enough friction to pull plate above it -lava added to mid ocean ridge creates new land -lava doesn’t push plates apart but the tall mountains that form at the ridge cause gravity to pull them down (ridge push->weak) -destructive plate margin-> plate sinks pulling the rest with it (slab pull)
76
Describe basaltic lava.
-low silica (45-55%) -low viscosity -eruption are effusive and regular -temp-> 1000-1200
77
Describe andesitic lava
Intermediate viscosity and silica content (55-65%) Temp->800-1000 Destructive eruptions
78
Describe rhyolitic lava
Viscous High Viscosity and high silica content (65-75%) Catastrophic eruption Low temps
79
Why does rhyolytic lava cause catastrophic eruptions?
-Magma traps gas and coagulates the vents blocking it -pressure builds up until sudden release
80
What type of lava is found in a shield volcano?
Basaltic
81
What type of lava is found in a composite volcano?
Rhyolitic
82
What is erupted from a composite volcano?
Lava bombs Ash Dust
83
Where do composite volcanoes form?
Destructive plate margins
84
Where do composite volcanoes form?
Constructive plate margins