VOLCANOES & EARTHQUAKES

• Where do 60% of active volcanoes occur?

  At the boundaries between tectonic plates
• What is the name of the belt where most volcanoes are found?

  The "Ring of Fire"
• What are "hot spots" in relation to volcanoes?

  Areas where volcanoes form in the interior of plates
• Where do earthquakes occur?

  At all plate margins
• What causes earthquakes at plate margins?

  Tension that builds up at all three plate margins
• What happens at a destructive plate margin during an earthquake?

  The subducted oceanic plate scrapes against the continental plate
• How does tension build at constructive plate margins?

  Along cracks within the plates
• What occurs at conservative plate margins?

  Tension builds when plates sliding past each other get stuck
• What scale measures the energy released by an earthquake?

  The Moment Magnitude Scale
• How is the Moment Magnitude Scale characterized?

  It is logarithmic
• How much more powerful is a magnitude 7 earthquake compared to a magnitude 6?

  10 times more powerful
• What are the primary and secondary effects of earthquakes and volcanoes?

  • Primary Effects: Immediate impacts (e.g., ground shaking)
  • Secondary Effects: Happen later, often due to primary effects
• What happens when tectonic plates jerk past each other?

  They cause shockwaves
• What is the focus of an earthquake?

  The point in the earth where the earthquake starts
• How do shallow foci affect earthquake waves?

  They produce stronger waves causing more damage
• What is the epicenter of an earthquake?

  The point on the earth's surface above the focus
• What are the differences between primary and secondary effects of earthquakes?

  • Primary Effects: Immediate consequences of the disaster
  • Secondary Effects: Result from primary effects, occur later