So What the Heck Caused Monday's Tremor?

La Grange residents whose homes were rattled by Monday's magnitude-3.2 seismic event still have no answer about the cause of the tremor. 

Well, not an affirmative answer anyway.

If you'll recall, reports of the tremor came in around 12:35 p.m. Monday. The Hinsdale Police Department told us right away that the cause was preliminarily believed to be a quarry blast.

Then the U.S. Geographic Survey (USGS) listed it as a magnitude-3.7 earthquake.

Then they changed it to a magnitude-3.7 quarry blast.

Then they changed it to a magnitude-3.2 quarry blast. 

So it was a magnitude-3.2 quarry blast. 

Or not. 

On Wednesday, the Illinois Department of Natural Resources (IDNR) concluded its inspection of the Hanson Material Services quarry, which was believed to be the source of the tremor. Turns out Hanson, who had denied that it was responsible for the tremor, did nothing out of the ordinary that day.

The other quarry in the area, operated by Vulcan Materials, told the Chicago Tribune that they were not blasting on Monday. 

So ... earthquake?

"The waveforms generated from the event indicate that it was a blast from a quarry in the area," USGS geophysicist Julie Dutton had told the Tribune Tuesday, making clear the occurrence was not being considered an earthquake.

Sigh.

You felt the tremor. What did it feel like to you? What else could it have been? Tell us in the comments!

• Quarry Operations Suspended; Hanson, Village Officials to Discuss Mining Practices
• Nov. 4 Quarry Blast 'Demands Additional Scrutiny,' Rep. Lipinski Says
• Quarry Blast 'Felt Like a Truck Hit the House,' 'Pictures Jumped Off Walls' (COMMENTS)
• Hanson Quarry to Review Monday Blast, Denies Responsibility for Tremor