MONTREAL -- A 4.0 magnitude earthquake hit just south of Montreal, near the U.S. border.

According to Earthquakes Canada, it happened at 5:38 a.m. Monday at a depth of five kilometres.

“Strongly felt in Saint Bruno, Vaudreuil and Montreal,” the agency stated. “There are no reports of damage, and none would be expected.”

Several people in Montreal's Verdun, Côte-des-Neiges-Notre-Dame-de-Grâce, LaSalle and Pierrefonds-Roxboro boroughs said they were woken up by the soft rumbling.

“We heard what sounded like a huge snap or blast…as if someone had driven into our building, followed by shaking,” Larry Shannon, who lives in Howick, Que., told CTV News.

“I watched my table shake uncontrollably and papers and things flying off from my wall unit… Our initial thought was that the gas station across the street had exploded or that someone had driven into the building or that a tree had fallen.”

Active seismic zone

"This is quite an active seismic zone in Eastern Canada," explained Claire Perry, an earthquake seismologist with Natural Resources Canada. "We record an earthquake in this western Quebec seismic zone, approximately one earthquake every five days – many of them too small to be felt."

"We would expect to see a magnitude 4 or so, one or two every ten years," said Perry, who added that a similar-strength quake occurred very close to the region in 2002.

"This is what we call an intraplate tectonic setting," said Perry. "What happens is, as plates move very, very slowly over time, stresses within the crust can accumulate along, sometimes, these pre-existing faults, and what occurs is a rupture, an earthquake in this vicinity, and this is what's happened here today."

Natural Resources Canada received more than 850 reports from people who felt the quake within and around the vicinity to about 100 kilometres away.

Perry said anyone who felt shaking or heard a loud bang in their home is urged to fill out a report on the Earthquakes Canada website.

"These reports really help us with historic seismicity and improving our understanding of earthquakes that occurred before digital instruments were available," she said.

Reminder to be prepared

The largest earthquake ever felt in the region registered at a magnitude of 5.8, on Sept. 16, 1732.

"It was pretty damaging and killed at least one person. If the same earthquake was to happen tomorrow, which is in the realm of possibility, it would be a lot more damaging," said Christie Rowe, associate professor in the faculty of Earth and Planetary Sciences at McGill University. 

"This is a great reminder that we do live in a seismically active zone and we should take precautions and be proactive and be prepared," added Perry.

That includes having:

  • an earthquake readiness kit
  • having extra water at home
  • flashlights
  • and making sure that heavy objects are well mounted to the walls

"An earthquake can occur anytime, anywhere and we cannot predict when and where they will occur, although we have good ideas of which zones are more seismically active… but really, everyone should be prepared," said Perry. "We don't just have to live in Western Canada to need to be prepared, because large earthquakes do occur in the east and can cause quite widespread damage when they occur near large urban centres."

Perry said we may experience aftershocks in the coming days or weeks, likely of lower magnitude than Monday's 4.0. It is possible to have a larger event, however "highly unlikely," she said.