Chaitén Eruption - LEDC

• Eruption began 2nd May 2008 - still ongoing
• First eruption in over 9000 years
• Shallow angle of subduction
• 1122m above sea level
• Obsidian rhyolitic lava dome in crater of Chaitén
• Caldera 3km wide
• Chaitén is a plinian volcano (erupts columns of gas and ash high into the stratosphere)
• Eruption was category 4/5 on the Volcanic Expolsivity Index (VEI)

LOCATION

• South Chilean Andes
• 10km north-east of the town of Chaitén 
• Occurs where the Nazca plate is subducting under the South American plate

• Huge ash cloud (20-30km) travelled into Argentina 
• Thunderstorms triggered
• 90% of Chaitén flooded due to pre-existing crater lakes
• Livestock killed due to suffocation
• 80-90% of Chaitén reported damage
• Ashfall up to 15cm deep led to water contamination - also mixed with heavy rainfall and generated lahars 
• Only 1 death - stress related
• Damage to airport/marine facilities hindered rescue
• Chaitén airport closed and some flights cancelled but minimal damage to aircraft

• Real-time monitoring set up by USGS May 16th (none before as volcano was dormant)
• 4000 people needed evacuation, 3900 had been by the next day
• Drinking of local water prohibited
• Fresh water and face masks were distributed
• 50km exclusion zone
• Financial aid supplied from around the world
• 90 day freeze on loan payments for those affected
• Volcano Disaster Assistance Program (VDAP) aided monitoring 
• Eruption helped to model future explosive rhyolitic eruptions 
• Chilean volcanic society set up