Tectonics - Case Studies Flashcards
EQ1 - Give an example for intra-plate volcanism (hotspot)
Hawaiian Islands
The Hawaiian Islands are a textbook example of intra-plate volcanism caused by a stationary mantle plume underneath the pacific plate…
EQ1 - What is a difference between the properties of a boundary-driven volcano, and a hotspot volcano? (give an example of one)
Kilauea
Unlike boundary-driven volcanoes, hotspots like Kīlauea erupt basaltic lava with low explosivity but long durations
EQ1 - How has the Hawaiian hotspot supported the theory of plate tectonics? How many islands are there
The Hawaiian hotspot has formed a linear volcanic chain
of over 130 volcanic islands stretching over 2,400 km
proving sea-floor spreading and supporting the theory of plate tectonics through palaeomagnetic data
EQ1 - What is the plate movement rate of the pacific plate?
10 cm/year northwest over stationary hotspot
EQ1 - Give an example of an intra-plate earthquake Area:
What is the earthquake frequency of the area?
When was the last major event?
The New Madrid Seismic Zone in the central USA
Magnitude 7/8 earthquake approximately every 500 years
1811–1812 earthquake sequence
EQ1 - Give an example of a divergent plate boundary?
When was the most recent activity?
What were the impacts?
Mid-Atlantic Ridge (Iceland)
Multiple eruptions on the Reykjanes Peninsula since 2021
Evacuations of nearby towns; temporary closure of the Blue Lagoon spa
EQ1 - Give an example of a conservative plate boundary
What is the probability for an earthquake?
San Andreas Fault – lateral movement of two plates
More than 99% chance of at least one magnitude 6.7 or greater earthquake over the next 30 years in California
EQ1 - Give an example of a convergent plate boundary
Japan Trench
Part of the pacific ring of fire off northeast Japan
Characterised by tsunamis and earthquakes.
EQ1 - What is a good example for pyroclastic flows, lahars and VEI 4
Mount Merapi (2010)
EQ1 - Tsunamis and Earthquake - Tohoku - Magnitude
9.0
EQ1 - Tohoku - Date
March 11th, 2011
EQ1 - Tohoku - Deaths, missing and injured.
Dead - Approx. 18,500
Missing - Approx. 2,500
Injured - Over 6000
EQ1 - Tohoku - Economic damage
Estimated at $360bn
EQ1 - Tohoku - Tsunami Facts
Waves reaching heights of up to 40 meters
Destroyed 150km of tsunami walls
EQ2 - Best case study for the spec focus: vulnerability and resilience
Haiti 2010 – high vulnerability, low resilience, poor governance
EQ2 - What are the 3 features of the PAR model, put into context using case study:
Nepal 2015
Root causes - Weakened governance and economic system by 10 year civil war
Dynamic pressures - Lack of local investment and training
Unsafe conditions - Unsafe infrastructure and poverty
EQ2 - Disaster impact (HIC vs LIC)
Chile 2010 vs Haiti 2010
Mount Merapi vs Eyjafjallajökull
Same year, different outcomes — governance, building codes
EQ2 - Give the hazard profile for Eyjafjallajökull 2010 (My Dad Ate Some Funky Porridge)
Magnitude (VEI) - 4 – moderate eruption
Duration - 39 days (main explosive phase: April 14 – May 23)
Areal Extent Regional – ash cloud spread across most of Northern and Western Europe
Speed of Onset - Moderate – signs of increased seismic activity detected weeks before eruption
Frequency - Low - frequency for this volcano – last eruption prior was in 1821–1823
Predictability - Medium – some monitoring (seismic + ground swelling), but eruption style and impact underestimated
EQ2 - Primary hazards - Eyjafjallajökull 2010
Ash plume (up to 9 km high), local flooding due to glacial melt, lava flows
EQ2 - Secondary hazards - Eyjafjallajökull 2010
Massive air travel disruption (95,000 flights cancelled), economic loss (~$1.7 billion in airline industry), tourism impact, livestock risk from ash
EQ2 - Best Case Study for development + governance
Christchurch 2011 (NZ) - Strong governance, good insurance, rapid recovery
EQ3 - Example of a Mega Disaster
2004 Indian Ocean tsunami
Regional/global impact, 230k+ deaths, lack of warning
EQ3 - Example of a multiple hazard zone
The Philippines
Earthquakes
Volcanoes
Typhoons
Landslides — compounding risk
EQ3 - Compare two hazard management cycles:
Haiti vs Japan 2011
Japan: rapid response/recovery
Haiti: slow, aid-dependent
EQ3 - Compare two Park Model’s
Nepal vs New Zealand
NZ: Steeper curve, faster recovery
Nepal: Gentle slope, slow due to governance/terrain
EQ3 - Modify Event - Example
Japan
Engineering design (aseismic technique)
Coastal defences
Urban planning
EQ3 - Modify vulnerability - Example
Japan
1st September Earthquake Education Day = community preparedness
Early warning systems e.g. The Japan Meteorological Agency (JMA) provides residents in Japan with Earthquake Early Warnings. This is a new system that issues prompt alerts just as an earthquake starts, providing valuable seconds for people to protect themselves before strong tremors arrive.
EQ3 - Modify loss - Example
NGO aid in Haiti
Short/long-term aid, Red Cross, community rebuilding
