Quake followed quarry blast

Scientists now say it’s likely that an earthquake shook the Western suburbs after a blast at a McCook quarry on Nov. 4.

According to a report on ABC 7’s website, the blast likely triggered what the U.S. Geological survey now believes was a release of tectonic strain.

“To release the strain basically means that the strain caused fracturing of the earth’s crust,” scientist Jim Dewey told ABC 7.

Planned quarry blasts don’t usually trigger larger follow-up tremors, the report said.