Tectonics case studies

Question 1

Mt. Pelee, Martinique, 1902

Answer 1

Volcanic eruption VEI 5
Destructive plate margin
Very viscous magma
29,025 killed – 3rd most deadly
700*C pyroclastic flows
Port of St. Pierre destroyed
Lack of monitoring and planning

Question 2

Mt. St. Hellens, USA, 1980

Answer 2

Volcanic eruption VEI 5
Explosive, acidic magma
61 killed
Located in remote forest – mainly backpackers
Good monitoring and historical data
Warning and evacuations

Question 3

Montserrat, 1995

Answer 3

Volcanic eruption VEI 3-4
Destructive plate margin
Very viscous, acidic magma (820-885*C)
19 killed
£41 m in damages
Caused migration and exclusion zones

Question 4

Hindu Kush, 2002

Answer 4

Earthquake 6.1 MW
150km North of Kabul – Convergent boundary
1000 dead, 4000 injured, 20000 homeless
Poor, war-torn, resource deficient region
Lack of preparation
8km depth, very shallow

Question 5

Taiwan, 2002

Answer 5

Earthquake 7.1 Mw
80km NE of Hualien – Destructive boundary
10 km deep – shallow
5 dead, 200 injured, buildings damaged, fires started
60 aftershocks and landslides – affected property and roads
Epicentre not close to urban centres
Earthquake proof architecture
People educated and prepared

Question 6

Hunga Tonga – Hunga Ha’apai, 2022

Answer 6

Volcanic eruption 6 VEI
Largest eruption since 1991
Destructive plate margin
Happened on remote archipelago
Created devastating tsunamis that left thousands homeless
Small volume of ash and SO2

Question 7

La Palma, 2021

Answer 7

Volcanic eruption 3 VEI
Constructive plate margin
445 km away from Africa
85 days of eruptive process
3012 acres of land covered in ash
Strato-volcano
7000 evacuated, 2651 buildings destroyed

Question 8

Japan, 2011

Answer 8

Earthquake 9.0 Mw and Tsunami
Destructive plate margin
800km/h wave speed, upwards of 40m in height
15,676 dead, 5712 injured, 4832 missing
45,700 buildings destroyed (11 hospitals)
Millions without water and electricity
Fukushima nuclear plant exploded
Local and international support – 70,000 shelters
$220B Cost

Question 9

Chile, 2010

Answer 9

Earthquake 8.8 Mw
Destructive plate margin
130+ aftershocks recoded
35km depth
521 dead, 56 missing
Infrastructure damaged – Main N.S road closed
1.5m Homes damaged
Up to $20B USD in damages

Question 10

Iceland, 2010

Answer 10

Volcanic eruption VEI 4
Constructive plate margin
Eruption lasted more than 6 months
9 km of tephra rose into the air
Airspace cluse of 20 countries – 10m affected
Flooding and pyroclastic flows
$3B USD Damages
Insurance affected
Tourism losses

Question 11

Indian ocean, 2004

Answer 11

Earthquake 9.0 Mw led to tsunami
Destructive plate margin
294k dead, 5m+ Homeless
65% of Indian ocean fishing destroyed
$5B USD in damages
Humanitarian response of up to $14B USD

Question 12

Mt Tambora, 1815

Answer 12

Volcano VEI 7 in Indonesia
Destroyed the whole island it was on
Killed 10000 directly, 60,000 non-directly
Decreased global temperatures by 0.4 – 0.7*C
‘the year without a summer’ in 1816
A result of Ash clouds and tephra
Famine, rise in food prices and looting

Question 13

Bam, 2003

Answer 13

Earthquake magnitude 6.6 Mw
7km hypocentre – very shallow
Directly under a city
Majority of people were asleep
Very old and weak buildings
3 hospitals destroyed – 2090 of medical staff killed
Very basic search and rescue
Cold winter – hypothermia was common

Question 14

Nepal, 2015

Answer 14

Earthquake 7.8 Mw – multiple hazard zones
LIC meant high population density and no preparation
9k dead, 22k injured, 500k homeless
Old, secluded population
Led to heavy poverty

Question 15

Christchurch, 2011

Answer 15

Series of earthquakes
Disruption to manufacture, production
Agriculture and finance markets unaffected
$15B USD cost

Question 16

Sichuan, 2008

Answer 16

Earthquake 7.9 Mw in NEE
$6600 USD GDP per Capita
87,150 dead, 375k injured, 5m homeless, 45m affected
$126B USD cost
Landslides caused ¼ of deaths
Corrupt government meant bad building quality
Relief – 130k soldiers to help with search and rescue
Medical services were provided preventing disease from spreading
$10B USD allocated for recovery
98% recovered after 2 years

Question 17

The Philippines, 1991

Answer 17

Hazard hotspot in the ring of fire
NEE
18 active volcanoes
Typhoon hotspot
1991, two volcanoes erupted;
7.7 Mw
80km away from Manila
1600 dead, 3000 injured, 200000 homeless
Viscous andesite lava
20 mit. Tonnes of Tephra
80 kph pyroclastic flows – resulted in lack of power and epidemic
Mass evacuation from early warning system