HAZARDS Flashcards
(136 cards)
1
Q
what is a MHZ?
A
multiple hazard zone
- where a country or region suffers two or more hazard types
2
Q
what is an example of an MHZ?
A
the Philippines
3
Q
what hazards does the Philippines face?
A
- volcanic eruptions
- tropical storms
- earthquakes
4
Q
what is an archipelago?
A
a group of islands
e.g. the Philippines
5
Q
What does the mercalli scale measure?
A
- the intensity of damage caused by an earthquake
6
Q
Where is the Philippines located?
A
It is an island arc in South East Asia, located 5-10 degrees north of the equator
7
Q
what plate margin does the Philippines lie on?
A
Destructive plate margin between the Eurasian and Philippine plate
8
Q
Why is the Philippines a MHZ?
A
- it lies on a cyclone belt
- intense monsoon climate
- vulnerable to tsunamis, earthquakes and typhoons
9
Q
Why is the Philippines vulnerable to tsunamis?
A
it has a high population density along its coastline
10
Q
When did Mt Nyiragongo erupt?
A
17th January 2002
11
Q
Where is Mt Nyiragongo?
A
the Democratic Republic of Congo
12
Q
Why did people live near Mt Nyiragongo, and how many?
A
- fertile farmland
- 500,000 people
13
Q
what were the responses to the eruption of Mt Nyiragongo?
A
- $15million worth of aid
- 400,000 people evacuated
- camps for displaced people
14
Q
What has been done to reduce the impact of future eruptions of Mt Nyiragongo?
A
- educated location residents on volcanic eruptions
- built a volcanic observatory for data gathering
15
Q
What were the impacts of Mt Nyiragongo’s eruption on Goma?
A
- 20% of homes destroyed
- 3m of lava coverage
- 100 deaths
16
Q
Why were people caught unaware of the eruption of Mt Nyiragongo?
A
The radio had said that there was no risk, so people were told to stay where they were
17
Q
What are some impacts of the Mt Nyiragongo eruption?
A
- frequent toxic gas emissions
- 147 deaths
- poisoned water source
- long-term respiratory problems
- unemployment
- buildings destroyed
18
Q
What plate boundary does Montserrat lie on?
A
- a destructive plate boundary between the Caribbean and North American plates
19
Q
When did the worst eruption in Montserrat occur?
A
25th June 1997
20
Q
what were the short-term effects of the eruptions in Montserrat?
A
- pyroclastic flows
- lahars
- ash and tephra fall
- earthquakes
- release of volcanic gases
21
Q
How many fatalities were there after the eruption in Montserrat?
A
19
22
Q
How is the volcano in Montserrat monitored?
A
- tiltmeters
- GPS satellite location
- seismographs
- COSPEC is used to measure gases
- frequent rock samples
- measuring the pH of rainwater
23
Q
what were the long-term effects of the eruptions in Montserrat?
A
- population shrunk
- no economic stability
- temporary housing
- heavily dependant on UK aid
- collapse of tourist and rice industries
- 2/3 of the island became an exclusion zone, forcing residents to the North
24
Q
What plate boundary is Eyjafjallajökull on?
A
divergent plate boundary between the North American and Eurasian plates
25
what were the impacts on Iceland?
- rapid increase in tourism to 1.7 million each year
26
what were the secondary impacts of Eyjafjallajökull's eruption?
- mudflows
- flooding
- extra train + ferry services
- schools closed
- 800 people evacuated
- 95,000 flights cancelled worldwide
- £62million paid out in travel insurance
- the Kenyan economy lost $3.8million a day
27
What were the warning signs that Eyjafjallajökull would erupt?
- earthquakes between 1992-98
- detected moving magma
- satellite images had shown the volcano changing shape
28
what were the primary impacts of Eyjafjallajökull's eruption?
- lava erupted from 12 vents
- ash soured 11,000ft into the air
- 5.5cm of ash fell on farmland
29
what were some long term responses to Eyjafjallajökull's eruption?
- rebuilding of damaged roads + bridges
- volcanic activity monitored
- text message warning system
- ash and debris was dug up from river beds to reduce flooding risks
30
what were some short term responses to Eyjafjallajökull's eruption?
- 800 people evacuated
- air space closed
- rescue teams sent out
- livestock kept inside
31
when did Eyjafjallajökull erupt?
- 2010
20th March
32
what were the impacts of the ash cloud from Eyjafjallajökull's eruption?
- hundreds of flights cancelled
- sky went black as the sun was blocked
- ash covered the soil
33
how was Eyjafjallajökull monitored?
- 80 seismometers
- 120 GPS antennae
34
How was the N1 protected?
(Iceland's ring road)
- nearby embankments were breached so water flooded the roads instead of expensive bridges
35
what are the characteristics of basic lava volcanoes?
- wide shallow base
- runny lava
- frequent, gentle eruptions
- less fatalities
36
what are the characteristics of acid lava volcanoes?
- thick, viscous lava
- tall narrow base
- infrequent, explosive eruptions
- more fatalities
37
what is a hotspot volcano?
a volcano in an intra-plate location.
e.g. Hawaii is in the middle of the Pacific plate
38
What is a convergent plate boundary?
- plates are moving together
- the denser oceanic plate moves below the lighter continental crust, creating a subduction zone
39
What can a convergent plate boundary create?
- earthquakes
- volcanoes
- fold mountains
40
What is a Divergent plate boundary?
The plates are moving apart, creating a gap that is filled with magma to form a volcano.
41
What is a conservative plate boundary?
Plates slide past each other in the same or opposite direction.
The 2 plates meet at a fault, where pressure builds until the 2 played jerk past each other creating an earthquake
42
What is a basic lava shield volcano?
Gently sloping cone with a large basw
43
What is an acid lava dome volcano?
Very steep volcano with lava so thick that it could form a plug or spire when forced out of the volcano
44
What is tephra?
Volcanic bombs which are emitted from a volcano during an eruption
45
What are examples of volcano monitoring equipment?
- ultrasound
- chemical sensors
- seismometers
- tiltmeter
- satellite images
46
What is ultrasound used for when monitoring volcanoes?
Monitoring the low frequency waves within magma as the gas and molten rock moves upwards
47
How are chemical sensors used when measuring volcanoes?
They measure increased sulphur levels
48
What is pyroclastic flow?
A mass of hot ash, lava fragments and gases ejected explosively from a volcano, and flowing at great speed
49
How are seismometers used when monitoring volcanoes?
They detect mini earthquakes that happen before an eruption
50
How are satellite images used when monitoring an eruption?
They show the warming of the grounds surface as the magma nears
51
How are tiltmeters used to monitor volcanoes?
They detect swelling on the side of the volcano, which occurs when magma is forced up to the surface
52
When was the Nevado Del Ruiz eruption?
13th November 1985
53
What was the population and death toll after the Nevado Del Ruiz eruption?
Population was 28,700
Death toll was 23,000
54
What were the warning signs before the Nevado Del Ruiz eruption?
- increased seismic activity
- magma nearing the surface
- increasing pressure
- gases released
- clouds of black smoke
- phreatic (steam) eruption
- increased ground temp
55
What impact did the weather have on the Nevado Del Ruiz eruption?
A storm has damaged electric structures so a warning couldn't be sent out.
The storm has masked the rumbling sounds of the volcano
56
What is a lahar?
A volcanic mudflow
57
What impact did the lahars have after Nevado Del Ruiz erupted?
- destroyed 5000 homes
- homeless
- $6billion in damages
- 150 died from infection
- killed 3/4 of Armeros residents
- it took 12 hours for the first people to be rescued
58
What factor led to the Nevado Del Ruiz eruption being so deadly?
- no evacuation or prevention
- damaged infrastructure
- recent storms
- soft mud made rescue hard
- warfare in Colombia
- lack of aid readily available
- dormant ice-covered volcano
59
What is the lithosphere?
- the crust and very top of the mantle
60
What is the asthenosphere?
The top layer of the mantle
61
Who was Alfred Wegner?
A geophysicist and meteorologist. He came up with the idea that the Earth's continents can move.
62
What is the evidence for plate tectonics?
- fossils
- patterns/bands of rock
- the shape of continents
- magnetic field patterns in iron containing rocks
63
What are the features of the Park model?
- relief
- rehabilitation
- rebuilding and reconstruction
64
What happens during the relief phase?
Teams arrive from outside the immediate area to help with search and rescue. Urgent medical supplies, search equipment, clothing and food may be flown in
65
What happens during the rehabilitation phase?
Lasts several weeks or months, actions restore the physical and community structures
66
What happens during the reconstruction phase?
Permanent changes are introduce to restore quality of life and economic stability to the original level or better
67
What were the social impacts of typhoon bopha?
- 1901 deaths
- 5,000 tourists stranded
- 834 missing
- thousands of people displaced
68
What were the economic impacts of typhoon bopha?
- flight and ferry services cancelled
- power outages
- crop damage worth 8.5 billion pesos
69
What were the environmental impacts of typhoon bopha?
- trees uprooted
- flooding and flash floods
- mudslides
70
What physical factors have put the Philippines at risk of hazards?
- hotspot location
- destructive plate boundary
- within a tropical storm belt
- climatic conditions
- archipelago
71
What human factors have put the Philippines at risk of hazards?
- deforestation
- LIC
- densely populated
72
What factors create a hotspot location?
- tectonic hazards
- hydro-meteorological hazards
- vulnerability
73
What were the social impacts of tropical storm washi?
- 1292 deaths
- 1049 missing
- 11502 houses destroyed
- schools and health centres closed
- contaminated water sources
- loss of crops
74
What were the economic impacts of tropical storm washi?
- 1.45 billion pesos of damage
- power outages
- loss of crops and fishing boats
75
What were the environmental impacts of tropical storm washi?
- flashfloods
- vegetation damage
- soil erosion
- landslides
76
When did mt pinatubo erupt?
1991
77
What were the social impacts of
Mt pinatubo erupting?
- 800 deaths
- evacuation
- 1.2 million people lost homes
78
What were the economic impacts of mt pinatubo erupting?
- airport closed
- 100 million in damage to aircrafts
- crops lost
- infrastructure damaged
79
What were the environmental impacts of mt pinatubo erupting?
- global temp dropped by 0.5°c
- lahars
- river erosion
- land covered by ash
80
When was the manila earthquake?
16th July 1990
81
What were the social impacts of the manila earthquake?
- 2412 deaths
- houses destroyed
- people missing
82
What were the environmental impacts of the manila earthquake?
- liquefication
- landslides
- flooding
83
What are the economic impacts of the manila earthquake?
- $369 million danages
- flights cancelled
- resort hotels damaged
84
When was the guinsaugon landslide?
2006
85
What were the environmental impacts of the guinsaugon landslide?
- very soft mud
- land had to be replanted to prevent erosion
86
What were the social impacts of the guinsaugon landslide?
- over 1100 deaths
- homes buried in mud
87
What were the economic impacts of the guinsaugon landslide?
- schools and homes rebuilt
- thousands of dollars in aid
88
When was the Philippines drought?
1989
89
What were the social impacts of the drought?
- loss of crops
- agriculture dying due to heat
90
What were the environmental impacts of the drought?
Cracked ground and vegetation loss
91
What were the economic impacts of the drought?
- forced to import 640000 tons of rice
- water rationing
- agricultural and fishery productivity dropped
92
When was the Haiti earthquake?
January 2012
93
What was the death toll after the Haiti earthquake?
316,000
94
What 3 factors made the number of casualties high after the Haiti earthquake?
- lack of infrastructure
- poor building quality
- wide spread poverty
95
What proportion of Haitis population are unemployed?
2/3
96
What proportion of the population lies below the poverty line?
50%
97
What were some impacts of the Haitian earthquake?
- injuries
- homelessness
- overcrowded hospitals
- blocked paths
- buildings collapsed
- loss of electricity
- disease
- looting
98
Where is Haiti?
An island in the Caribbean, it shares its border with the Dominican Republic
99
What plate boundary is Haiti on?
Conservative plate boundary between the North American and Caribbean plates
100
What magnitude was the Haiti earthquake?
7.0
101
Why did aid take a long time in the Haiti earthquake?
- the port was destroyed
- roads were blocked
- not enough space on the runways
102
When was the Japanese earthquake and tsunami?
2011.
103
What plates does Japan lie on?
Destructive plate boundary where the Pacific Plate sinks below the Eurasian plate.
104
What will the primary effects of Japan? earthquake?
- Ground shaking
- subsidence
- liquification
- fatalities
- injury
- people missing
- buildings destroyed
- infrastructure damaged.
105
What was secondary effects of the Japanese earthquake?
- Tsunami
- flooding
- disrupted shipping and travel
- agricultural loss
- nuclear power plant damage
- radiation
- large economic costs
- regular blackouts
- water contamination
106
What the earthquake proof buildings in Japan effictive?
They were effective with the earthquake, but the tsunami damaged them.
107
What magnitude was the Japanese earthquake
9. With many aftershocks between six and seven.
108
When was the Christchurch earthquake?
2011
109
Where is Christchurch?
It is the second largest city in New Zealand.
110
What plate boundary does New Zealand dry on?
Destructive plate boundary where the Pacific Plate is subducting below the Indo Australian plate.
111
What magnitude was the Christchurch earthquake?
6.3.
112
What time did the Christchurch earthquake strike? And what was the impact of this?
It was at lunchtime, so there was many people in the city centre.
113
What were the primary effects of the Christchurch earthquake?
- Buildings collapsed
- buses crushed
- infrastructure damage
- at least 185 deaths
- Soil liquification
- injuries
- power loss
- water and sewage pipes damage.
114
What was some secondary effects of the Christchurch earthquake?
- Children enrolled in schools across New Zealand
- high. rebuilding costs
- Many people unable to return home
- fires
- could no longer host the rugby World Cup
- mental health issues
- Electricity loss
- job loss.
115
What was some immediate responses to the Christchurch earthquake?
- Local people removing survivors from the rubble
- aid
-rescue team sent
- severely damaged buildings demolished
- a phone ban.
116
What will have some longtime responses to the New Zealand earthquake
- the cathedral was demolished
- fundraising events
- memorial.
117
What factors can determine the scale of the impacts and responses of an earthquake?
- How many people live there?
- wealth
- Transport networks
- how much the country has to help
- how prepare people are,
- how good the health care is,
- construction standards
- the location and strength of the earthquake
- what technology they have.
118
What is an example of a small magnitude earthquake?
North England earthquake, which was 3.9 magnitude.
119
What is a hazard profile?
A diagram that shows the main physical characteristics of different types of tectonic hazards.
120
War characteristics are found in a hazard profile.
- Magnitude
- speed of onset
- duration
- aerial extent
- spatial predictability
- frequency.
121
What human factors can influence the impacts of the hazard?
- Infrastructure
- governance
- political conditions
- communication systems
- income levels
- preparedness and education
- rapid urbanisation
- population density
- housing quality
- health care
- efficiency of emergency services
- building regulations.
122
How are earthquakes distributed globally?
About 95% occur close to or at a plate of boundary, with many occuring around the 'Pacific Ring of Fire'.
123
What type of plate boundary are powerful earthquakes usually associated with?
- convergent
- conservative
124
How are volcanoes distributed globally?
Most active volcanoes occur or near plate boundaries, with 75% around the 'Pacific Ring of fire'
125
What type of plate boundary can you find volcanoes at?
- convergent
- divergent
- hotspots
126
How a tsunami is distributed globally?
Over 70% occur around the Pacific Ocean, mostly due to convergent boundaries
127
What are the features of hazards at divergent plate boundaries?
- mild, shallow earthquakes
- small eruptions
- basaltic lava which is runny with high temperature and gas content
128
What are the features of hazard so convergent plate boundaries?
- strong earthquakes
- explosive eruptions
- thick lava with high gas content and lower temperatures
129
Who are the features of hazards that transform plate boundaries?
The plates stick together, which causes a significant buildup of pressure and powerful earthquakes.
130
what are P waves?
primary waves
131
What are the features of p waves?
- travel through solids
- vibrate in direction of travel
- travel at 4-8 km/s
132
What are s waves?
Secondary waves.
133
What are the features of s waves?
- Travel is only through solid rocks.
- travels at 2.5-4 km/hr
- Vibrate at right angles to direction of travel
134
What are L waves?
love waves
135
What are the features of L waves?
- near to ground surface
- travel at 2-7 km/hr
- Rolling motion produces vertical ground movement.
136
Which seismic waves are the most destructive?
S and L waves as they have a large amplitude
