TECTONICS

Cards (26)

  • Continental plate
    Less dense, more thick
  • Oceanic plate

    Denser, less thick
  • Constructive plate boundary

    • Two plates moving away from each other, magma rises in the middle and creates new land
  • Destructive plate boundary

    • Two plates moving towards each other
  • Outcomes of destructive plate boundaries
    • Two continental plates - fold mountains form
    • One oceanic and one continental - oceanic gets subducted
  • Conservative plate boundary
    • Plates rubbing side by side
  • HIC - Christchurch, New Zealand
    • South Island, 22/2/2011
    • Australian and Pacific plate - conservative and destructive
    • Earthquake was 6.1, lasted 12 seconds (had been a 7.1 6 months prior)
    • Epicentre was 10km from Christchurch
    • Shallow focus of 5km
    • 181 people were killed
    • Over half the deaths were due to building collapse and fire
  • LIC - Nepal
    • Destructive plate boundary - Indian and Eurasian plate, both continental
    • 7.9 Richter scale
    • 8.2 km from surface - shallow
    • Kim from capital
  • Monitoring
    Using scientific equipment to detect activity
  • Monitoring techniques
    • Remote sensing (satellites detect changes in heat and shape of volcano)
    • Seismicity (seismograph record earthquakes)
    • Ground deformation (changes in volcano shape detected by laser beams)
    • Geophysical measurements (detect gravity changes as magma rises)
    • Gas (detect gasses released as magma rises)
    • Hydrology (measurements of gasses dissolved in water)
  • Prediction
    Using scientific evidence to guess activity
  • Prediction methods

    • Volcanoes (base predictions off monitoring methods)
    • Earthquake (predicted based off of historical evidence, plate margins, pre shocks, animal activity)
  • Protection
    Designing infrastructure to resist hazard
  • Protection methods
    • Volcanoes (little to be done, embankments or explosions can divert lava)
    • Earthquakes (building constructed to improve stability, tsunami walls, drills keep people educated)
  • Planning
    Identifying and avoiding high risk locations
  • Planning methods

    • Volcanoes (hazard maps showing location and likeliness can ensure evacuation zones)
    • Earthquakes (mapped high risk areas, high value land protected)
  • Reasons people live in hazardous areas
    • Hazards don't happen often, low risk
    • People in poverty have other things to worry about
    • People unaware of risk
    • Plate margins coincide with desirable locations
    • Volcanos bring fertile soil, rocks for building, mineral deposits, hot water
    • Falt lines allow water to reach the service - good for deserts
    • Good monitoring lowers risk
    • Better design can withstand earthquakes
  • Iceland benefits from living in a hazardous area:
  • Christchurch – effects:
    -          28 billion dollars of damage
    -          181 people died, 2000 injured
    -          Couldn’t hold rugby world cup
    -          Road damage due to liquification – could reach people
    -          Schools shared classrooms
    -          Part of glacier broke off – made iceberg
    -          80% of city was without electricity
    -          City’s cathedral lost its spire
  • Christchurch – response:
    -          Search and rescue from Australia, UK, USA, Japan, Taiwan, China
    -          Australian government donated 6.7 million dollars
    -          Full emergency response planned in two hours
    -          Electricity was restored 80% in 5 days and 95% in two weeks
    -          During building repairs, shipping containers converted to shops
    -          2700 chemical toilets sent to Christchurch
    -          Water supplies restored 70% in one week
  • Long term response:
    -          Rebuilding and reconstructing
    -          Returning lives back to normal
    -          Preventing further risk-          Rebuilding and reconstructing
    -          Returning lives back to normal
    -          Preventing further risk
  • Immediate response:

    -          Search and rescue
    -          Keeping survivors alive
    -          Medical care
    -          Food, water, shelter
  • New Zealand – immediate:
    -          Emergency services acted quickly
    -          Farmy army – farmers provided machines and muscle for clean up
    -          30000 chemical toilets provided
    -          Government provided temporary housing and kept damaged houses watertight
    -          Australia gave 5 million in aid
    -          International help from US, UK, Taiwan, Australia
  • New Zealand – Long-Term:

    -          As HIC – economy was strong enough for rebuild
    -          Canterbury earthquake recovery authority created
    -          Christchurch divided into green, orange, white and red zones
  • Nepal – Immediate:
    -          Search and rescue teams arrived quickly from UK, India, China
    -          300000 people migrated from Kathmandu
    -          Field hospitals set up to support overcrowded hospitals
    -          500000 tents needed to provide shelter
    -          Helicopters rescued people caught in avalanches on Everest
  • Nepal – Long-Term:

    -          Financial aid pledged by many countries
    -          Thousands homeless people to be rehoused
    -          Tourism to be boosted
    -          Held a conference to discuss rebuilding and aid