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