How We Perceive Earthquakes (i.e Intensity)

Intensity

  • how we perceive earthquakes (the intensity we feel) depends on several factors…

  

  1. magnitude:

      1. lower magnitude = less intense

         1. less energy, waves less powerful 2. shorter shaker time

  1. distance from epicenter

      1. further = less intense

         1. seismic waves attenuate (weaken) as they travel

  1. duration (how long)

      1. shorter = less intense

         1. larger earthquakes can have several minutes of shaking

  1. foundation (ground) material

      1. solid rock = least intense 2. well-compacted sediment = less intense 3. water-saturated sediment = more intense (potential for liquefaction)

  1. building structure (building reaction to ground acceleration)

      1. in general:

         1. brick and concrete = bad 2. wood, steel, and reinforced concrete = good