Take 2: Magnitude vs. Intensity

2min Novice

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Is seismic intensity really different than an earthquake's magnitude?

Magnitude and intensity are both related to the size of an earthquake, but they each measure different aspects. Magnitude (which measures the energy released at the source of the earthquake rupture and is calculated using measurements from seismic instruments) is a single value. Seismic intensity(which is the measurement of the strength of shaking at a specific location  determined from effects on people, human structures, and the natural environment) produces a range of shaking intensities in different locations.

In this animation we use a lightbulb as an analogy.

CLOSED CAPTIONING: .srt file is included with the download. Use an appropriate media player to utilize captioning.


 Intensity is mostly controlled by three factors: Magnitudehowbigwastheearthquake

  • DistancefromthehypocenterIntensityvariesfromplacetoplaceand
  • Local rock and soil conditions:

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