Earthquake - 3.0 M - SOUTH DAKOTA

USGS ^ | 1/16/12 | USGS

[Elsie]

OOOooooh!

Did the earth move for you, too?

[JustaDumbBlonde]

"A 3 for example is ten times as strong as a 2."

Not an uncommon misunderstanding. The magnitude scale is really comparing amplitudes of waves on a seismogram, not the strength or energy of the quakes.

So, a magnitude 3.0 is 10 times bigger than a 2.0 earthquake as measured on seismograms, but the 3.0 quake is about 31.6 times stronger than the 2.0.

Since it is really the energy or strength that knocks down buildings, this is really the more important comparison.

[Godzilla]

Need to go further west to the Rocky Mountains :)