A 5.1 magnitude earthquake struck 19 kilometers north of Southville, Ontario Friday at 9:22 am and was felt as far away as Montreal, Northern NY and Vermont the US Geological Survey (USGS) reported.
Residents in the area said the shaking lasted about 30 seconds.
“It was like a massive explosion that went off, it just started shaking and the walls of the bakery were moving,” said Dan Duggan owner of the Pontiac Home Bakery in Shawville, Que..
“I thought it was my propane tanks exploding. We were evacuating employees out of the building. It lasted for about 25 seconds and it went on for about another minute,” he said.
“I’ve lived through earthquakes before, but never anything like that.”
There was no damages or injuries reported but tremors were reported felt even in Maine. The main quake was followed a few minutes later by a magnitude 4.4 aftershock. A magnitude 5 earthquake is generally the threshold strength of any damage.
Earthquakes are common in Southern Canada and Northern New York with more than 450 earthquakes occurring in Ontario annually alone. Of those, only about 1% will exceed a magnitude 4.
The USGS designates the area the “Western Quebec Seismic Zone.” Earthquakes cause damage in the zone about once a decade. Smaller earthquakes are felt three or four times a year. The two largest recorded earthquakes in the zone happened in 1936 (6.1) and 1732 (6.2). The 1732 quake caused significant amount of damage in Montreal.
The majority of all earthquakes and seismic activity occur along faults which are located along plate boundaries. The Western Quebec seismic zone is far from the nearest plate boundaries, which are in the center of the Atlantic Ocean and in the Caribbean Sea.
The seismic zone is laced with known faults but numerous smaller or deeply buried faults remain undetected. Even the known faults are poorly located at earthquake depths. Accordingly, few, if any, earthquakes in the seismic zone can be linked to named faults. It is difficult to determine if a known fault is still active and could slip and cause an earthquake. As in most other areas east of the Rockies, the best guide to earthquake hazards in the Western Quebec seismic zone is the earthquakes themselves.
The characteristics of earthquakes in the western U.S. are different than in the east. East of the Rockies, an earthquake can be felt over an area as much as ten times larger than a similar magnitude earthquake on the west coast.
A magnitude 4.0 eastern earthquake typically can be felt at many places as far as 100 km (60 mi) from where it occurred, and it infrequently causes damage near its source. A magnitude 5.5 eastern earthquake usually can be felt as far as 500 km (300 mi) from where it occurred, and sometimes causes damage as far away as 40 km (25 mi).
There have already been 12 earthquakes in the Western Quebec Seismic Zone in 2013.