Volcanic hazards

• What is the main method of measuring volcanic hazards?

  Volcanic Explosivity Index (VEI)
• What does the Volcanic Explosivity Index (VEI) measure?

  It measures the explosiveness of volcanic eruptions
• What is the range of the Volcanic Explosivity Index (VEI)?

  0 to 8
• What VEI score do quiet lava-producing eruptions typically receive?

  Scores of 0 to 1
• What VEI score did the pyroclastic explosion of Mt. St. Helens receive?

  It scored 3
• What is a criticism of the Volcanic Explosivity Index (VEI)?

  It doesn't account for gas emissions
• What is a volcano?

  An opening in Earth's crust connected to magma
• What is ejected from a volcano?

  Molten lava, gases, and pyroclastic material
• Where are volcanoes globally distributed?

  At mid-ocean ridges and plate boundaries
• What are hotspots in relation to volcanoes?

  Areas of crust with unusually high heat
• What type of magma is associated with constructive plate margins?

  Basaltic magma
• What is the characteristic of basaltic lava?

  It is runny and low in silica
• What type of eruptions are typical at constructive plate margins?

  Little violence with gases escaping easily
• What type of volcano is formed at constructive plate margins?

  Shield volcano
• What type of magma is associated with destructive plate margins?

  Acidic rhyolitic magma
• What is a primary volcanic effect of explosive eruptions?

  Generation of ash and tephra
• How far can fluid basalt flows extend from an erupting volcano?

  Tens of kilometers
• What are pyroclastic flows?

  Rock fragments traveling across the ground
• What speed can pyroclastic flows reach?

  Up to 80 km/h
• What can volcanic gases lead to?

  Potential harm to people and agriculture
• What is acid rain formed from?

  Gases emitted by volcanoes and moisture
• What can tsunamis generated by volcanic eruptions cause?

  Widespread flooding and destruction
• How can volcanic eruptions affect climate?

  Ash clouds can reflect solar radiation
• What happened at Lake Nyos in 1986?

  Gas eruption suffocated entire villages
• What was the impact of the Krakatoa eruption in 1883?

  Killed 40,000 and triggered tsunamis
• What type of eruption is associated with Kilauea in Hawaii?

  Gentle lava eruption
• What were the effects of the Pinatubo eruption in 1991?

  Mass evacuation and mudflows occurred
• What are the primary volcanic effects?

  • Ash and tephra generation
  • Lava flows
  • Pyroclastic events
  • Volcanic gases
• What are the secondary volcanic effects?

  • Acid rain
  • Tsunamis
  • Flooding
  • Climate change
• What are the methods for mitigating volcanic eruptions?

  • Land use planning and hazard mapping
  • Community preparedness and evacuation
  • Hazard-resistant design
  • Prediction and monitoring
• What role do hazard maps play in volcanic risk mitigation?

  They guide evacuation planning and land use
• What is a key warning sign of volcanic activity?

  Thermal imaging to observe movement
• What can be done to design buildings to resist volcanic hazards?

  Strengthening roofs to prevent collapse
• What is the purpose of community preparedness in volcanic eruptions?

  To lower risks to life during eruptions
• What is the significance of magma movement monitoring?

  It helps predict potential eruptions
• What is the effect of rapid melting of ice and snow during eruptions?

  It can lead to lahars and flooding
• What is the impact of volcanic ash on aviation?

  It poses a large hazard to aircraft
• What is the relationship between volcanic eruptions and agriculture?

  Volcanic gases can harm crops and livestock
• What can happen to structures during a volcanic eruption?

  They can be destroyed by lava flows
• What is the effect of volcanic eruptions on local ecosystems?

  They can cause significant disruption and harm