Chaiten Case Study

Chaitén volcano is located in southern Chile, 10 km NE of the town of Chaitén on the Gulf of Corcovado. The volcano contains an obsidian lava dome in a 3.5 km wide caldera. The volcano is occasionally covered with snow, but does not contain a glacier. Two small lakes occupy the caldera floor on the west and north sides of the lava dome. The 2008 Chaiten eruption was the first explosive Rhyolite eruption to be scientifically studied

• · Initial eruption led to an ash column 18km, 6 hours duration
• · Continuous ash emission as high as 30km with large explosions continuing from 2-8^th May
• · Lava dome extrusion with sustained vapour and ash column
• · Situated above a subduction zone where the Pacific Ocean Plate is consumed beneath the South American continental crust
• · Was a caldera 2.5km wide and 4km long, composed of viscous rhyolitic lavas and pyroclastics
• The nature of the volcanic hazard
• · By late May the lava eruptions had generated a new dome of around 540,000m in area, containing 55million m of new material
• · The ash column was at its peak between 20-30km high
• · The fall of ash from…