Oklahoma Just Experienced Its Largest Earthquake on Record

The earthquake that shook Pawnee, Oklahoma, on Sept. 3 is now the state's largest temblor on record, according to the U.S. Geological Survey, which just upgraded the magnitude to 5.8. "Changes in estimated magnitude for an earthquake are common in the hours-to-days following the event, as more data are analyzed in greater detail than is possible in the first minutes after the earthquake occurs," according to a USGS statement.