CHRISTCHURCH casestudy - seismic event example Flashcards
DATE of the event
CHRISTCHURCH
22nd feb 2011
LOCATION of the event
CHRISTCHURCH
Canterbury region - South Island (NZ) - 10km of south/east centre of Christchurch (at time was 2nd most popular city)
- NZ located in pacific ocean
NATURE of the seismic event
CHRISTCHURCH
magnitude: 6.3 - lasted about 12 secs
aftershocks: 2 aftershocks on the 13th of June; 5.5 and 6.0 magnitude. Then, a series of smaller shocks over a two-hour period
already WEAK?
CHRISTCHURCH
damage to buildings/infrastructure; on the 4th of sep 2010, earthquake of 7.1 magnitude
WHY did it happen?
CHRISTCHURCH
Two sides of the fault slipped sideways relative to each other but one side of the fault was also thrust upwards over the other side
occurred on the conservative plate margin where the Pacific plate slide past the Australian plate in the opposite direction
the Greendale Fault was not previously known about
key FACTS of the country GDP per capita population life expectancy total damage
(CHRISTCHURCH)
$41,555
over 4 million
81 years
£3 billion
SOCIAL impacts - SHORT term
CHRISTCHURCH
- 181 people killed / 2000 injured
- 80% of the city was without electricity
- doctor’s surgery had to be moved to the car park
- 50% of Christchurch’s building were severely damaged
- 215 schools had to be closed
ENVIRONMENTAL impacts - SHORT term
CHRISTCHURCH
- liquefaction caused the upwelling of over 200,000 tonnes of silt into the build-up area of the city; 80% of the city’s sewers / water supply systems were destroyed
- part of the country’s longest glacier (size of 20 football pitches) was broken off; creating large iceberg
- violent shaking of ground caused it to rise up by 1m in some places
- landslides and rock falls in Port Hills
SOCIAL impacts - LONG term
CHRISTCHURCH
- schools had to mix classrooms and some families moved into one room (warmth as the shaking loosened/broke their windows)
- damaged roads from liquefaction caused difficulties for people/emergency services to move about
- people affected mentally; especially children
ECONOMIC impacts - LONG term
CHRISTCHURCH
businesses put out of action for a long time; loss of income
- a lot of doctors left the area; moved to USA/Europe
- Christchurch could no longer host Rugby World Cup; tourism industry lost the benefits
- some economists estimated could take over 50 years to fully recover
response BEFORE the earthquake
CHRISTCHURCH
- several houses already built to match earthquake code; houses often needed to be ‘patched up’ rather than re-built
- regular tremors meant insurance companies were used to damage; able to prepare
response DURING the earthquake
CHRISTCHURCH
- 30,000 chemical toilets were provided
- areas were zoned (green/orange/white/red) to classify damage/cost of repairs
- international aid; £6-7 million
- temporary houses were provided
- 16 St John’s ambulances out within 30 mins of the quake
- Canterbury Art Gallery turned into an emergency response centre
- 300 Aus police flown in; organised evacuations/search and rescue teams
- Satellite imagery was provided; to help with allocation of aid and rescue from the US and France
response AFTER the earthquake
CHRISTCHURCH
- paid $898 million in building claims
- by august, all sewers/water was restored
- august: 80% of roads and 50% of footpaths repaired
- Red Cross provided grants for families with children under five living in badly damaged houses; to help with electricity bills
- gov. guaranteed support for whole area; allowing country to be ‘mobilised’ for re-building
