A case study on the 2008 eruption of Chaitén in Chile. Suitable for A2 Geography

1. Chaitén
Volcano case study

2. 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

3. How the tectonic forces created this volcano
VEI: 4

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.

5. • By late May the lava
eruptions had created a
new dome 540,000m2
across containing
55,000,000m3 of
volcanic material.

6. Primary effects Secondary effects
• Tephra - solids
• Pyroclastic flows
• Lava flows
• Volcanic gases
• Lahars
• Flooding
• Volcanic landslides

8. 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

9. 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

10. 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.

11. 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.

12. 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 Term
Long term

13. 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 Term
Long term

14. 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 Term
Long term