earthquake case studies

chile earthquake introduction

• 27th feb 2010

• destructive subduction plate margin (nazca plate is being subducted beneath the sa plate)

• 8.8 on richter scale

• epicentre was roughly 30km off the coast - triggered a tsunami warning

• focus: 35km deep

• smaller aftershocks followed

primary effects of chile earthquake

• 500 people killed and 12 000 injured - 800 000 affected

• 220 000 homes, 4500 schools, 53 ports and 56 hospitals + other public buildings were destroyed

• port of talcahuanao and santiago airport badly damaged

• much of chile lost power, water supplies and communications

• cost estimated at $30 billion us dollars

secondary effects of chile earthquake

• rescue efforts were hindered as communications were lost

• lack of / contaminated water supplies may have resulted in dehydration or even diseases such as cholera

• 1500km of roads damaged, mainly by landslides - remote communities cut off for many days

• several coastal towns devastated by tsunami waves

• several pacific countries struck by tsunami - warnings prevented loss of life

• fire at a chemical plant near santiago - area had to be evacuated

immediate responses of chile earthquake

• emergency services acted swiftly - international help needed to suplly field hospitals, satellite phones and floating bridges

• temporary repairs made to the important route 5 north-south highway within 24 hours, enabling aid to be transported from santiago to affected areas

• power and water restored to 90% of homes within 10 days

• national appeal raised $60 million us dollars - enough to build 30 000 small emergency wooden shelters

long term responses of chile earthquake

• a month after the earthquake, chile’s government launched a housing reconstruction plan to help nearly 200 000 households affected by the earthquake

• chile’s strong economy based on copper exports could be rebuilt without the need for much foreign aid

• president announced it could take 4 years for chile to recover fully from damage to buildings and ports - assured everyone that slowly but surely they would recover

nepal earthquake introduction

• 25th april 2015

• destructive collision plate margin - indo-australian and eurasian plate are colliding

• 7.8 on richter scale

• epicentre was 80km north-west of the country’s capital kathmandu (affected one of the most densely populated areas in nepal)

• focus: 15km deep (shallow focus)

• number of major aftershocks such as 12th may which was a 7.3 on richter scale

primary effects of nepal earthquake

• 9000 people died & 20 000 injured - over 8 million people (⅓ of nepal’s population) affected

• 3 million people made homeless

• electricity and water supplies, sanitation and communications affected

• 1.4 million people needed food, water and shelter in the days and weeks after the earthquake

• 7000 schools destroyed and hospitals overwhelmed

• international airport became congested as aid arrived

• 50% of shops destroyed, affecting food supplies and people’s livelihoods

• cost of damage estimated to be $5 billion us dollars (less damage than chile as they had less money to spend in the first place)

secondary effects of nepal earthquake

• ground shaking triggered landslides & avalanches blocking roads and hampering relief efforts

• avalanches on mt everest killed at least 19 people (greatest loss of life on mountain in a single incident)

• an avalanche in langtang region left 250 people missing

• landslide blocked the kali gandki river 140km north-west of the capital kathmandu - many people evacuated in case of flooding

• occured on land so did NOT trigger tsunami

immediate responses of nepal earthquake

• search and rescue teams, water and medical support arrived quickly from countries such as uk, india and china

• helicopters rescued many people caught in avalanches on mt everest and delivered supplies to villages cut off by landslides

• half a million tents needed to provide shelter for the homeless

• financial aid pledged from many countries

• field hospitals set up to support overcrowded ones

• 300 000 people migrated from kathmandu to seek shelter and support with family and friends

• social media widely used in search and rescue operations and satellites mapped damaged areas

long-term responses for nepal earthquake

• roads repaired and landslides cleared - lakes, formed by landslides damming river valley, need to be emptied to avoid flooding

• thousands of homeless people to be re-housed and damaged homes repaired + over 7000 schools to be rebuilt or repaired

• stricter controls on building codes

• in june 2015, nepal hosted an international conference to discuss reconstruction and seek technical and financial support from other countries

• tourism, a major source of income, to be boosted - by july 2015 some heritage sites reopened and tourists were starting to return

• repairs to everest base camp and trekking routes - by august 2015, new routes had been established and the mountains were reopened for climbers

• in late 2015 a blockage at the indian border badly affected supplies of fuels, medicines and construction materials

why is the depth of the focus important?

the shallower the earthquake the more the effects will be felt, in turn causing more damage

how does depth of focus link to case studies?

the nepal earthquake was significantly shallower than chile - 15km compared to 35km

why is location of epicentre important?

the epicentre allows us to determine where the most damage will happen and where the most death and destruction will occur

how does location of epicentre link to case studies?

epicentre of chile earthquake was 30km off the coast, so would have affected less people directly but triggered a tsunami warning

however, the epicentre of nepal earthquake was near the country’s capital, so more people would have been affected

why is population density important?

the higher the population density, the more people will be at risk

population density - link to case studies?

the nepal earthquake affected one of the most densely populated areas in nepal while the chile earthquake happened off the coast so no one lived there??

why are construction standards important?

the better the construction standards that buildings are built to, the less risk of damage (+ the better they can withstand damage)

construction standards - link to case studies?

as chile is a hic, there would have been better construction standards and so less damage while in nepal, there would have been lower construction standards as it is an lic (+ due to corruption) and so more damage was caused

medical facilities - importance?

if there are better and more advanced medical facilities, those who were injured by the earthquake could be treated & have better chance of survival

medical facilities - link to case studies?

hospitals were either destroyed or overwhelmed in both countries so there would have been less medical facilities

but chile was wealthier so may have had more advanced medical facilities

resources and finances - importance

the more resources and finances a country has, the quicker they can recover from an earthquake or even prevent some of its effects happening in the first place

resources and finances - links to case studies?

chile was the wealthier country so they could recover from the damage quicker (even though there was more damage as they had more to spend in the first place) and nepal was the poorer country so they wouldn’t have had enough resources and finances taking longer to recover