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Canterbury EQs - Coggle Diagram

- - - - Divergent boundaries
        
        Two tectonic plates sliding apart from each other
        
        Creates or expands ocean basins and/or rifts
        
        Examples include: Mid-Atlantic Ridge, East Pacific Rise, and East African Rift
      - Convergent boundaries
        
        Two tectonic plates sliding into each other
        
        Creates either subduction zone (volcanic island chains) or continental collision (mountain formation)
        
        Examples include: Japanese island arc, the Andes, and the Himalayas
      - Transform boundaries
        
        Two tectonic plates grinding against each other
        
        Neither tectonic plate is created or destroyed, instead faults are created as from friction of two plates, leading to strong EQs
        
        Examples include: San Andreas Fault, Alpine Fault, and North Anatolian Fault
  - - - P (primary) waves
        
        Fastest type of seismic wave at approx. 8km per second
        
        Able to travel through all three states of matter: solids, liquids, and gases
        
        First type of seismic wave to be felt be people
        
        Does little damage; shakes furniture and rattles windows
        
        Is a type of body wave; travels within the interior of the Earth
      - S (secondary) waves
        
        Half the speed of P waves at approx. 4km per second
        
        Occurs after P waves
        
        Does significant damage; moves ground vertically and horizontally
        
        Is a type of body wave; travels within the interior of the Earth
      - L (Love waves)
        
        Travels at approx. 2 - 3km per second
        
        Generally occurs after S waves
        
        Does extensive damage; generates visible ripples on ground
        
        Is a type of surface wave; travels along Earth's surface
  - - - Inner Core (> 5 200°C, 1 300km, Solid)
      - Crust (0 - 500°C, 100km, Solid)
      - Mantle (1 000 - 3 700°C, 2 900km, Solid)
      - Outer Core (4 500 - 5 200°C, 2 250km, Liquid)
- - - - Densely populated areas were inflicted with widespread casualties and damage
      - Not all buildings were up to code, meaning higher risk of collapsing
      - City areas at higher risk of falling debris because of high-rises
      - More pedestrian and vehicle traffic in densely populated areas, meaning higher risk of human casualties and congestion
      - Infrastructure at high risk of being damaged and not functioning properly, making civilians vulnerability to basic needs cutoff
    - - Canterbury is one of the largest food producers in New Zealand, growing the majority of wheat in the country. This risks food production being affected
      - Canterbury contains multiple state highways, particularly SH1, which are heavily relied upon for land transportation in the South Island. It is also used to transport food crops, risking major impact to both industries
      - Many agricultural areas are only accessible by one or two roads, risking cutoff if they were damaged
  - - - EQs can cause water and sediment to rise from aquifers as the soil loses it's strength and acts similar to a liquid. This is called liquefaction
      - Canterbury, particularly Christchurch, has many aquifers because it's soil contains mostly sediment and the rivers flowing from the Southern Alps increase water intake in these aquifers. This means, the region as a whole is at a higher risk of being severely impacted by an EQ
      - Aquifers exist in loose, sediment soils where water can easily enter. Water is sourced from rainfall or rivers. This creates a risk of damage to surrounding areas
    - - Many faults runoff the Alpine Fault into the Canterbury Region, meaning a higher risk of fault rupture and EQ in proximity or within the region
      - The Alpine Fault is underneath the Southern Alps at 60km long and within the regional limits of Canterbury
      - Because the Alpine Fault is a transform fault, it increases the risk of more severe and damaging EQ to the Canterbury region
- - - - Over 450 000 tonnes of liquefaction deluged the city during the Feb 2011 EQ
      - 185 people died, 133 in the CTV and PGC House buildings, and 6 500 were injured in the Feb 2011 EQ which costed an estimated $77 000 000 00
      - 2 people died and 100 were injuried in the Sep 2010 EQ with a cost of $4 000 000 000. 1 person died and 46 were injuried in the Jun 2011 EQ and costed $6 000 000 000
      - Famous structures such as the Christchurch Catholic and Anglican Cathedrals, as well as, The Civic, were badly damaged or destroyed following the Feb 2011 EQ