Earthquakes in South Dakota

{Modified Mercalli Intensity definitions} {Richter Scale Magnitudes}

{Richter Scale Graphic Representation}

     

Learn more at the USGS Earthquake Education Site

Small earthquakes happen every one or two years in the state and are not large enough to be considered threatening to life or property. Most people experience a low rumble in their homes, but no damage. There have been almost 100 documented earthquakes in South Dakota since the first recorded one in 1872. Likely causes of these earthquakes are adjustments deep in the basement rocks underlying the state or ongoing rebound of the earth’s crust from compression by ice sheets during the last ice age.

 

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USGS Interactive Map showing earthquakes in or near South Dakota

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