McCook Quarry Blast Likely an Earthquake, Scientists Say
November 14, 2013 (MCCOOK, Ill.) (WLS) -- Scientists say it's likely that an earthquake shook the western suburbs after a blast at a quarry.The U.S. Geological Survey, the earthquake experts, now agree that two things happened November 4th, a routine quarry blast that was not very noticeable, followed seconds later by an earthquake very noticeably felt by thousands for miles and miles.
Because they happened seconds apart in the same area, they now think they are related. The research suggests that planned quarry blasts do not cause larger follow-up tremors, but the U.S. Geological Survey now believes that it is more probable than not that the quarry blast and what followed seven seconds later are related.
In other words, the blast likely triggered what the USGS now believes was a release of tectonic strain.
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