The natural gas explosion that rocked Concord Township and neighboring communities early Sunday may have demolished two homes and damaged a significant number of other dwellings but it didn't register as even a blip on Ohio's earthquake-sensing equipment.

Mike Hansen, state geologist in charge of the Ohio Seismic Network, said he received three e-mail postings regarding the explosion. Two of these posts came from Mentor and one from Painesville. Each sender wondered whether an earthquake had occurred, Hansen said.

Nope, said Hansen, following a check of the system that includes a unit in Ashtabula County's Jefferson Village and another one at Lakeland Community College. A third unit at Lake Erie College (and the closest one to the explosion) is temporarily not in use.

Hansen said that following the e-mails he checked the equipment but nothing jumped out at him beyond what is called "cultural clutter," or typical background noise generated by human activity.

"We don't usually see a response since gas explosions are air blasts and so are not typically detected. If a blast occurs in a quarry then we may detect it because that is a ground blast," Hansen said.

- Jeffrey L. Frischkorn
JFrischkorn@News-Herald.com