1.4 Flashcards
What affects an earthquakes severity?
Magnitude - energy
Distance from the epicentre/focus
Bedrock + soil
What is a method to test if there is a correlation between deaths/injuries and magnitude of a quake?
To use spearman rank formula:
Rs = 1 - (6Ed^2)/n(n^2-1)
E = the total of Rs = overall value of Rank D = difference N = number of values/sites
What is an example of a developed nation that had an earthquake?
Christchurch , New Zealand in 2011 had a 6.2 magnitude earthquake that was caused by a release of tectonic strain along the conservative margin.
What were the primary hazards of the Christchurch earthquake?
1) 185 deaths - buildings collapsing and catching fire
2) 3129 people injured
3) April 2013 total estimated costs $40 billion
4) Liquefaction in eastern suburbs produced 400,000 tonnes of silt
5) Damage to buildings as 100,000 buildings were damaged and 10,000 were demolished
6) phone lines and communication was shut off
What were the secondary impacts of the Christchurch earthquake?
3.5m tsunami in Tasman lake causing Tasman glacier to trigger
Water pipes and bridges and roads were damaged
80% of Systems of sewerage and water was severely destroyed
80% of residents said psychological factors had impacted the,
Divorce rates increased from 211 to 249
Population declined for the first time in a long time
Christchurch couldn’t host the rugby World Cup so they lost tourism
What made the Christchurch earthquake impacts worse?
1) Epicentre was close to Christchurch
2) Focus was shallow only 5km underground
3) occurred during a lunchtime in the CBD, meaning it was busy and buildings were still damaged by the previous quakes
4) seismic waves were very strong (L waves)
5) liquefaction was significantly greater then the 2010 quake, undermining lots of infrastructure.
What were the responses to the quake from people in New Zealand?
Rescue crews were dispatched from across the globe
Australia gave $5 Million in aid
Government declared it a national emergency
The area was split into 4 zones : green, orange, white and red
Green allowed building , red was very unsafe ground
Charities helped eg save the children
What are some facts about the New Zealand earthquake?
The largest aftershock was 2 hours after 5.9
Aftershocks were recorded after a month the earthquake happened
This was created as the pacific plate slid past the Australian plate at the boundary causing horizontal movement with a slight vertical uplift.
Was there any warning systems in place for Christchurch?
New Zealand has a history of being very tectonically active so quakes were common therefore, people had some knowledge that a big earthquake could happen
Scientists didn’t know that the fault existed so it was hard to predict.
What is an example of a developing nation that was hit by a powerful earthquake?
The Haiti earthquake in 2010 and the Dominican Republic
What are some facts about the Haiti earthquake in 2010?
It was a large scale earthquake on the 12 January 2010
It occupied 1/3 of the island
Displaced many people across islands
Was 25km south west of the capital Port-au-prince
Was many aftershocks
Was caused by an undiscovered fault - Leogane fault
Was a shallow focus
What were primary impacts of the quake in Haiti?
Around 300,000 deaths but that varies
- influential figures in the UN were killed
Buildings were destroyed many residences
80% of schools and 60% of hospitals destroyed
Left many people homeless and homes destroyed
Disrupted transport systems
What were secondary impacts of the quake in Haiti?
2 Million people affected 1100 temporary camps Outbreaks of cholera killed many Storms and flood soon after quake Damage of $11.5 billion
What were responses to the Haiti earthquake?
Search and rescue teams were immediate Sensitive equipment was used - flown in Aid was sent in from utilities UK gave £100 Million used for sanitation mainly 3/4 of houses were repaired Caused out-migration from port-au-prince World bank gave £100 Million
How was the damage in Haiti influenced by factors?
It is a LEDC
Has limited supply of resources
No regulations to secure what happened after an earthquake
Housing were cheap and poor quality
