Seismic waves of 3.9 magnitude were recorded in the area of a mine in Utah after it collapsed. Scientists believe the collapse caused the disturbance. Below are some previous mine collapses in the United States that also produced earthquake-like activity.

Nov. 2, 2006: Mine in southwest Virginia, seismic reading of 4.3.

March 6, 2000: Mine in central Utah, seismic reading of 4.2.

Jan. 29, 2000: mine in southwestern Wyoming, seismic reading of 4.4.

May 13, 1999: Abandoned mine under Kansas City, Kan., seismic reading of 3.0.

Jan. 19, 1999: Coal mine 15 miles northeast of Tuscaloosa, Ala., seismic reading of 4.0.

Feb. 3, 1995: mine in southwestern Wyoming, seismic reading of 5.4.

March 12, 1994: Akzo Nobel salt mine in western New York, seismic reading of 3.6.

Source: Associated Press archives, U.S. Geological Survey.