1
Q
What is a tectonic hazard
A
a tectonic event that has the ability to cause harm onto people or property
2
Q
What is a plate boundary
A
distinct zones at the edges of tectonic plates where earthquakes usually occur
3
Q
What are intraplate regions
A
an area where intraplate earthquakes occur due to a build up of stress by continental rifting or its transfer from other regions
4
Q
What is a divergent plate boundary
A
where plates move away from eachother
5
Q
What is a conservative plate boundary
A
where plates slide past eachother
6
Q
What is a convergent plate boundary
A
where the oceanic crust slides under the continental crust
7
Q
What makes a volcano more explosive
A
- higher silica content
- high viscocity
- lower temperatures
- more gas
- water content
8
Q
What are characteristics of the continental crust
A
- made of less dense rocks
- created at destructive plate boundaries
9
Q
What are the characteristics of oceanic crust
A
- made of denser rocks
- formed at divergent plate boundaries
10
Q
What is the lithosphere
A
the fusion of the crust and upper most solid mantle
11
Q
What is the aesthenosphere
A
the ductile/rheid layer of the Earth that allows the plate to move
12
Q
What is the mantle
A
- 82% of Earth’v volume (aesthenosphere to outer core)
- made of silicate rock rich in iron and magnesium
13
Q
What is the core made up of
A
- mostly iron and nickel
- outer = liquid
- inner = solid
13
Q
What are deep sea ocean trenches
A
the point where oceanic plates subduct beneath continental plates
14
Q
What are fold mountains
A
when subduction causes mainly sedimentary rocks to warp and be pushed upwards from collisions
15
Q
What is the benioff zone
A
the area where earthquakes occur
16
Q
What is subduction
A
when one edge of a plate is force beneath another
17
Q
What are mantle plumes
A
abnormally hot rocks which are moving up the Earth
18
Q
What are hotspots
A
when mantle plumes breach the surface and spew lava
19
Q
What do mantleplumes/hotspots create
A
- intraplate volcanoes
- island arcs
20
Q
What is the proof of Alfred Wegners theory of continental drift
A
- plates are puzzle pieces and create Pangea
- continents broke away and drifted apart
- tropical fossils sound in Antartica
- glacial deposits in Brazil/tropical/desert areas
- rock layers matching in different countries
- fresh water fossils found across oceans
21
Q
What is seafloor spreading
A
the divergent motion of oceanic plates and rise of balsatic magma to produce mid-ocean ridges
22
Q
How does paleomagnetism prove seafloor spreading
A
magma locks in the Earth’s magnetic polarity, which shows changes in geology
23
Q
What is slab pull
A
- when dense oceanic crust becomes heavier than the aesthenosphere and descends at subduction zones
- the weight of the sinking cooling plate causes a major pulling motion
24
What is ridge push
1. when plates are hotter and less dense than their surroundings and rise
2. form mid-ocean ridges
3. slide sideways off high areas
4. pushes plates infront of them
25
What is the modified Mercalli scale
1. a measure of intensity
2. based on the observations of people who experienced the event
3. I-XII
26
What is the Moment Magnitude Scale
1. a measure of the total energy released by an earthquake as soon as it occurs
2. 1-10
3. logarithmic
27
What is the Volcanic Explosivity Index
1. a logarithmic scale that measures a volcanoes column height, volume of tephra released, and qualitative observations
2. 0-8
28
What is the hypocentre/focus
where the stress is released
29
What is the epicentre
the point directly above the hypocentre
30
What are the characteristics of P-Waves
1. fastest
2. reach the surface first
3. compressional waves
4. travel through liquids and solids
31
What are the characteristics of S-Waves
1. slower than P-waves
2. only pass through solids
3. lateral movements
32
What are the characteristics of L-Waves
1. slowest
2. cause the most damage
3. high amplitude
33
Why does felsic magma contain more silica, allowing it to produce more explosive eruptions
form at convergent boundaries where continental and oceanic crust is melting
34
What are primary hazards
hazards that occur during the natural disaster
35
What are secondary hazards
hazards that occur after the natural disaster
36
# Secondary Hazard:Earthquake
What is liquefaaction
When ground shaking causes surface rocks to lose strength and become more liquid than solid
37
# Secondary Hazard:Earthquake
What is a landslide
when ground shaking places stress on the cliff slope causing a rapid downslope movement
38
# Secondary Hazard:Earthquake
What is a tsunami
1. a series of large-waves caused by underwater volcanoes or earthquakes
2. vertical displacement of the crust causes the water column to do the same
39
# Secondary Hazard:Earthquake
What is an avalanche
when ground shaking on the cliff slope causes the rapid downstream movement of large quantities of snow
40
# Secondary hazard:Earthquake
How are diseases caused by earthquakes
debris contaminates water sources allowing harmful pathogens to grow and spread
41
# Primary hazards:Volcanoes
What are lava flows
streams of lava erupted from the volcano
42
# Primary hazards:Volcanoes
What are pyrochlastic flows
a mixture of dense hot rock, lava, ash, and gases that are ejected at high speeds from the side of a volcano
43
# Primary hazards:Volcanoes
What is ash fall
small particles of rock and volcanic glass that lands after eruptions blast them into the air
44
# Primary hazards:Volcanoes
What is a gas eruption
When volcanic gases (water vapour, CO2, SO2) that were dissolved in magma are released into the atmosphere
45
# Secondary Hazards:Volcanoes
What are wildfires
Great fires caused by heat from a volcano
46
# Secondary Hazards:Volcanoes
What are lahars
hot masses of rock, mud, and water quickly that tarvel down the side of a volcano
47
# Secondary Hazards:Volcanoes
What are Jokulhlaups
heavy and sudden floods caused by the melting of now and ice
48
Why does mafic magma contain less silica, allowing it to produce less explosive eruptions
formed at divergent boundaries where magma comes from the mantle, making them less viscous which allows highly explosive gas to escape
49
What is a risk
the factors that lead to some individuals or groups becoming more vulnerable to a hazard
50
What is vulnerability
all the factors that when combined make an individual or a group more susceptible to tectonic disasters
51
What is the capacity to cope
refers to all the strengths, attributes, and resources available within a community to manage and reduce disaster risks
52
What is resilience
the ability of a community to rehabilitate and reconstruct after disasters and return to a high quality of living standards
53
What are root causes
fundamental characteristics of a place
54
What are dynamic pressures
changes or deficits in a place, caused by root causes
55
What are unsafe conditions
how hazardous a place is, result of root causes and dynamic pressures
56
What are some examples of root causes
1. limited access to power, infrastructure, resources
2. dominant idologies, political systems, and economic systems
57
What are some examples of dynamic pressures
1. lack of training, local investment, press freedom, proper infrastructure
2. rapid population change
3. rapid urbanisation
4. deforestation
58
What are some examples of unsafe conditions
1. physical environment
2. local economy
3. social relations
4. public actions
59
What is the Pressure & Release Model
a theory that states that a disaster is caused by a progression of vulnerability and a natural hazard
60
What is governance
decision making
61
How is governance used in relation to tectonic disasters
1. planning regulations
2. disaster preparedness and response
3. financial management
4. local to global scale
62
What is involved in administrative governance
1. implementation, recording, monitoring, and enforcement of policies
2. land use planning
3. creating and enforcing strict license schemes
62
Who are the players involved in disaster governance
1. governments
2. local authorities
3. NGOs
4. IGOs
5. businesses
63
What is involved in economic governance
1. control the country's economic activities
2. controls the realtionship with other countries
3. controls the financial decisions
64
What is involved in political governance
1. creation of policies
2. discussion of plans
3. decide what to do before, during, and after a disaster
65
Are we experiencing more disasters
no, they are staying at a constant rate
66
why are disaster statistics unreliable
1. can be misreported by the government
2. greater inaccuracies (especially in developing countries)
3. don't account for post-disaster affects
67
What are multiple hazard zones
a location where two or more geographical or hydrometerological hazards can occur at any point
68
What is a tectonic mega-disaster
A large scale disaster on either spatial extent or in terms of economic/human impacts
69
How has globalisation made tectonic mega-disasters more dangerous
efficiency of supply chains decrease
70
What is the Just in Time economic model
when a company orders small shipments of raw material and products when it forcasts it will need it
71
How are volcanoes predicted
1. tiltmeters measure volcanic bulging (magma filling the chamber and SO2 increases)
2. earthquake sensors measure mini-earthquakes and rumbling (as magma moves)
3. cameras look for signs
72
How are earthquakes forecasted
## Footnote
using probabilistic forecasting
monitor where an earthquake hasn't occured in a while
73
How can countries modify the loss of a tectonic hazard
1. provide the poor aid
2. provide insurance schemes for the rich
3. use the aid of NGO's effectively
4. have effective search and rescue operations
74
How can countries modify the vulnerability of a tectonic hazard
1. have accurate prediction and warning systems
2. educate the community on preparedness
3. educate the community to change their behaviour to better cope with hazards
75
How can countries modify the event of a tectonic hazard
1. have greater control of the environment
2. avoid hazardous areas through land use zoning
3. create infrastructure with hazard-resistant design
76
what is mitigation
attempting to reduce the effects of the event
77
What is adaptation
conducting changes to minimise the harm of an event
78
In the hazard management cycle what encompasses mitigation
building defences
79
In the hazard management cycle what encompasses preparedness
1. the education and training of the community
2. having accurate and updated warning systems
3. having emergency services and hazard shelters
80
In the hazard management cycle what encompasses response
1. having easy to access evacuation shelters
2. having good emergency managemetn and govenance
81
In the hazard management cycle what encompasses recovery
the rebuilding, restoring, and redesigning of the affected areas
82
What are earthquake resistant designs
when buildings are designed in such a way that reduces collapsing
83
What are examples of earthquake resistant designs
1. cross-braces
2. base insulators
3. mass dampeners
4. shinbashira
5. shear walls
84
How can enigneering solutions modify the event
building defences can prevent hazards from affecting a greater part of the population
85
How can the diversion of lava flows or lahars modify the event
using barriers to divert these reduces damages and deflects danger to less vulnerable areas
86
How can land use zoning modify the event
understanding where high-risk areas are so they aren't built upon will mean there is nobody in vulnerable areas
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