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Flashcards in Seismicity- Case Studies Deck (11)
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1

Background facts on Haiti

- situated to the north of Caribbean Plate on a transform conservative plate boundary with the North American Plate moving west
- 7.0 magnitude on 12th January 2010 at 16:53 local time
- focus 13km below surface (shallow)
- epicentre 16km west of Port-au-Prince
- tremors lasted for one minute

2

Primary effects in Haiti

- 3 million people affected
- around 230,000 identified as dead
- 300,000 injured
- 1 million homeless
- 250,000 residences and 30,000 commercial buildings collapsed or severely damaged e.g. the UN and World Bank HQs as well as schools, hospitals, government buildings
- roads, bridges, telephone lines, electricity systems damaged
- port was hit making it hard to ship in aid to the capital

3

Secondary effects in Haiti

- spread of fire and disease
- poor living conditions and lack of sanitation:; cholera
- shortages of food and water
- small local tsunami
- one fifth of jobs lost
- 52 aftershocks in following 12 days (one was 5.9 magnitude)

4

Why was Haiti so badly affected despite the magnitude not being that great

- shallow depth
- struck most densely populated area of country
- poorest country in the Western Hemisphere
- buildings in poor condition and not constructed to be earthquake resistant
- 3 million people live in Port-au-Prince with the majority in slum conditions after rapid urbanisation
- only one airport with one runway; the control tower was badly damaged and the port was also inaccessible
- aid piled up but lack of trucks and people to distribute it so took days to arrive
- rescue teams took up to 48 hours due to problems at the airport so local people had to dig people out with bare hands
- severe shortage of doctors meant people died of injuries such as broken limbs

5

What was the building like in Haiti

There were building codes but they were not conformed to and so a typical finding was that insufficient steel had been used to reinforce concrete. Half of all the buildings were destroyed.

6

Christchurch background facts

- New Zealand is a highly tectonically active country
- the South Island is on a conservative boundary between the Indo Australian and Pacific Plates though the 2011 earthquake was caused by smaller faults that ruptured, previously unknown to geologists
- a wealthy country; GDP $41 per capita
- very mountainous interior so majority live on coastal plains (where Christchurch is located); population distribution is uneven which has a disproportionate effect on the population when earthquakes hit
- built on alluvial sediment (allowing liquefaction)
- strict building codes reviewed every 10 years
- The Greendale Fault ruptured Sept 4th 2010; 7.1 at 10km deep
- The Christchurch Earthquake 22nd Feb 2011 12:30pm; 6.3
- struck at built up area; 10km SE of the city at 5km deep at lunchtime when many were on the streets

7

Primary effects in Christchurch

- water pipes, roads, bridges, power lines, phone lines damaged
- brought down many buildings previously damaged in sept 2010
- many heritage buildings severely damaged e.g. the cathedral and Christ church's tallest building the Hotel Grand Chancellor (which was demolished)
- extensive liquefaction; eastern parts of the city were built on a former swamp and properties were covered in thick layers of silt
- water and sewage on the streets
- house foundations cracked and buckled; many houses had to be demolished and some areas of suburbs were never recoccupied
- confusion and panic in the centre; phone lines immediately jammed
- 185 people died, thousands are injuried
- 115 died when 6 storey Canterbury Television Building collapsed
- 169 people died in the centre of the city

8

Responses in Christchurch

- National Crisis Management Centre activated and a national state of emergency declared
- Japan, UK and other countries sent specialist rescue teams
- land use zone map drawn up in June 2011 showing red areas where rebuilding was dangerous
- Central Business District remained cordoned off more than 2 years afterwards
- electricity restored to 75% of the city within 3 days but water and sewerage systems took years to restore
- 70,000 people left the city
- Timaru, a town 157km South saw a swell in population by 20% and thousands of pupils enrolled in schools in other cities and towns
- over 1000 buildings had to be demolished including the spire of the cathedral which remains un-reconstructed

9

What is the current situation in Christchurch

- remains a "ghost town"
- waiting for insurance payouts and planning decisions
- charities have been set up e.g. "Greening the Rubble" schemes building temporary parks on the sites of destroyed buildings
- widespread frustration with the rate of recovery

10

LEDC case study and MEDC case study?

LEDC- Haiti
MEDC- Christchurch

11

Human factors involved in Haiti

GDP is $1200
Life expectancy 62.51 years (20 years lower than the UK)
Total fertility rate 2.98 per woman
Literacy rate 52.9%