Rare Amherstburg earthquake shows region could be better prepared, says emergency coordinator

Thursday night's 3.6 magnitude earthquake shows officials that the region could be better prepared, according to the emergency management coordinator for Essex County. 

The quake's epicentre was located in Amherstburg, and people felt the big rumble at about 8:01 p.m.

"We don't have these events very often," said Dan Metcalfe, who was "pretty shocked" by last night's earthquake.

Metcalfe said the region is "very lucky" there were no injuries or damage, and he admits officials could be better prepared.

"Some of the municipalities have adopted an alerting system called EverBridge, and we're moving more towards an all-hazards approach so that we're prepared for hopefully anything."

Metcalfe said he did not consider the thunderous sounds he heard last night could be an earthquake at first, speculating it was an explosion or something falling off a passing truck.

Salt mine blasting?

Some thought it might be from the Windsor Salt mine or a nearby quarry, but Maria Cioppa said that's unlikely. She's an associate professor in the department of Earth and Environment Sciences at the University of Windsor

"The pattern that we see on the seismographs it a little bit different than for an explosion at a salt mine than it is for an earthquake and we see something that is more standard for an earthquake," she said, adding that the quake occurred much deeper underground than a mine or quarry.

Cioppa said the bedrock in the area has fractures and faults in it. An earthquake can be caused if the bedrock moves along those lines. 

"We're basically in the middle of a stable plate, but all the plates around here are parts of other plates," said Cioppa, explaining that a long time ago, many plates came together to form the one the Windsor area is on top of. 

This earthquake was a little stronger than most in this region, but small earthquakes are not uncommon.

Cioppa said thousands happen across Canada each year.

When the damage could start

According to Earthquakes Canada, although this quake didn't cause any damage, one of its magnitude could have.

Nick Ackerley is a seismologist with the organization. He said there's a couple more factors besides the magnitude of a quake that causes damage.

"It crucially depends how far you are from it and for these very small earthquakes where you're talking about light damage it also depends how deep the earthquake was,"said Ackerley.

"It was definitely deeper than five kilometres ... so that means if you're right above it you're still five kilometres away from it."

Depending on depth and location, Earthquakes Canada said a magnitude five or six quake could cause chimneys to start crumbling, for example.

Ackerley said there's still a possibility for an aftershock that could happen in weeks, months or not at all.