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A case study on the 2008 eruption of Chaitén in Chile. Suitable for A2 Geography
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ChaiténVolcano case study
Location
• Chile, S. America
• LEDC
• Nearest towns
▫ Chaitén (10km SW of volcano)
▫ Futaleufu (70km SE of volcano)
Date season, weather
• 1st May 2008
▫ Most violent on 5th May
Time day/night
• Started midnight on 1st May 2008
How the tectonic forces created this volcano
VEI: 4
Eruption
• Consisted mainly of rhyolitic lava.• It produced numerous plumes, pyroclastic flows
minor earthquakes and lahars, and building a new lava dome on the north side of the old one.
• The ash cloud was up to 17km high. • Caldera Volcano - A central spine of lava
was pushed out of the new dome, but will likely collapse.
• It produced high Plinian eruption columns of ash, gas and rock.
• By late May the lava eruptions had created a new dome 540,000m2
across containing 55,000,000m3 of volcanic material.
Primary effects Secondary effects
• Tephra - solids
• Pyroclastic flows
• Lava flows
• Volcanic gases
• Lahars
• Flooding
• Volcanic landslides
Social impacts
• Loss of social amenities
• Change of risk perception
▫ Not safe anymore
• Effects on the strength of the community
▫ As of the end of 2008, 900 people remain in the town
Economic impacts
• Costs of emergency rescue▫ US$36million
• Costs of repairs to infrastructure• Insurance costs
▫ At least US$12million on insured buildings• Losses to business/industry
▫ Air travel, • Losses to employment
▫ Businesses shut down• Losses to family wealth
▫ Assets lost• Losses to international trade
▫ Loss of US$700,000 for airliners
Environmental impacts
• Lahars
▫ Cutting off transport links, destroying communication links as well as animal habitats.
• Ash fell up to 15cm deep
▫ Killed many farm animals and local wildlife due to respiratory problems.
Demographic impacts
• 1 human fatality due to stress.
• 45% do not intend to return to Chaitén.
• 43% had not made a decision.
• Only 12% are ready to return.
• Permanent evacuation, plans to rebuild town 6km away out of volcano’s path.
Management/Responses
• Development of the volcano prediction systems
▫ Real-time seismic monitoring began on 16th of May 2008, and that was conducted by the USGS (United States Geological Survey).
▫ Chile's geological survey (SERNAGEOMIN) created a new program to improve monitoring at 43 high-threat volcanoes.
Short TermLong term
Management/Responses
• Land-use planning – is it a high risk area? Should settlements be built?
▫ Relocation of town
▫ In January of 2011 the Chilean government decided to restore the old town and not to build a new town.
Short TermLong term
Management/Responses
• Aid
▫ The government issued a monthly disaster compensation of $1200-$2200 per month per family.
▫ Financial aid to small businesses was granted and 90 day freeze on payment of existing loans.
• Insurance
▫ At least US$12million paid out to owners of insured buildings.
Short TermLong term