A small seismic event hit Berks County, Pennsylvania, overnight. The earthquake was so minor that you might not have even felt it.
The magnitude 1.6 earthquake struck a little less than 4 miles west-southwest of the small town of Leesport around 2:06 a.m. Friday, the U.S. Geological Survey reported. It originated just over 3 miles under the surface.
If you slept through it, you aren't alone. As of 9 a.m., only two people had reported feeling anything on the USGS site.
"Typically, people report feeling earthquakes larger than about magnitude 3.0," the USGS says on its website.
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Earthquakes aren't common in Pennsylvania, but do happen, said the Pennsylvania Department of Conservation & Natural Resources. However, "there are a few areas with a history of small events. A sudden release of stored energy along part of a fault plane within the earth causes an earthquake."