hazards

• subduction zone


  where the oceanic plate descends beneath the continental plate into the mantle.
• conservative margin


  where two plates slide past one another
• richter scale


  used to measure the intensity of earthquakes and has a logarithmic scale.
• focus


  the point beneath the earth's surface where an earthquake occurs
• tectonic plate


  a section of the earth's crust that floats on the mantle due to convection currents.
• natural hazard


  A natural event that has the potential to endanger human life, the economy and property
• Factors affecting hazard risk

  poverty, deforestation, urbanisation
• slab pull


  at destructive boundaries the oceanic plate, because it is denser, is forced downwards at the subduction zone and this process continues to pull the plate downwards
• ridge push


  At constructive boundaries ocean ridges are forced upwards, gravity pushes the plates apart
• plate


  A section of the earth's crust that 'floats'slowly over heavier, semi-molten rock in the upper mantle.
• convection currents


  heat from the mantle forces currents of molten magma to rise - as they rise towards the crust, they cool and fall again - this movement carries the plates.
• Case Study of a HIC Earthquake

  L'Aquila, Italy 2009
• Effects


  What the hazard does to people. These can be primary and secondary
• Responses


  How people react to a tectonic event, These can be immediate and long term.
• Case study of a LIC earthquake

  Gorkha, Nepal 2015
• Primary effects of Nepal Earthquake

  9000 dead, villages such as Yanglakot cut off, 7000 schools destroyed, stored grains and crops in the Kathmandu valley lost.
• Secondary effects of the Nepal Earthquake

  trekking routes closed, 23% energy shortage, small industries collapsed, poverty increased by 30%
• Immediate responses to the Nepal Earthquake


  open air shelters set up in Kathmandu, airport closed, tourists stopped visiting, appeals for aid
• Long Term responses to the Nepal Earthquake

  BBB approach, focus on safety of schools and hospitals, government education schemes, government increased seismic research
• Immediate effects of the L'Aquila Earthquake

  over 300 dead, 67 000 homeless in hilltop villages , 300 historic buildings destroyed and San Salvatore hospital severely damaged
• Secondary effects of the L'Aquila Earthquake

  Landslides blocked roads, burst water main in Paganio triggered a mudflow, university student numbers at L'Aquila fell, businesses and tourism income fell
• Immediate responses to the L'Aquila earthquake

  Italian red cross searched for survivors, utility bill repayments suspended, EU offered $500 m from its Solidarity Fund, shelters set up.
• Long term responses to the L'Aquila earthquake


  local taxes suspended for the year, students made exempt from university fees, court case against scientists for failing to predict earthquake, renewed emphasis on following building codes.
• factors linked to WEALTH that influencing the effects and response to a natural hazard

  access to medical care, training, emergency services, construction standards and transport infrastructure
• factors not linked to wealth that influence the effects and response to a tectonic event

  depth of focus, magnitude, distance from epicentre, building density, time of day/week
• prediction


  attempts to forecast when and where the hazard will strike based on current knowledge
• Monitoring


  recording physical changes such as earthquake tremors
• planning


  action taken to enable communities to respond and recover from an event
• protection


  actions taken before a hazard strikes to reduce its impact
• examples of planning


  evacuation plans, warning systems
• examples of protection


  educating people, improving building design
• Ways of predicting volcanic events

  monitoring seismic waves, gas emissions, ground deformation and satellite images
• Ways of predicting earthquakes

  seismometers monitor size and frequency of foreshocks, animal behaviour, laser beams.
• Advantages of living in tectonic environments

  geothermal energy, precious minerals, fertile soil, opportunities to develop tourist industry