The Alberta Energy Regulator is working to determine if a fracking operation caused an earthquake near Sylvan Lake and Red Deer on Monday.
Natural Resources Canada said a 4.6-magnitude earthquake rocked parts of central Alberta just before 6 a.m. The federal department’s website said the tremor was classified as a light earthquake.
The AER has confirmed Vesta Energy had been fracking in the area just prior to the quake, which was detected by the company’s private seismic monitoring devices around 12 kilometres south of Sylvan Lake at a magnitude of 4.16.
The AER said the earthquake was reported to them by the company at 6:20 a.m.
“We are currently reviewing the events to determine if the incident is due to hydraulic fracturing activities or natural causes,” said Natalie Brodych, spokeswoman with the AER.
The regulator said Vesta has stopped work at the site while the AER investigates whether fracking led to the quake.
Earthquakes Canada initially had trouble pinpointing the earthquake, locating it first northeast of Red Deer, then south of the city. The most recent update has placed it 19 kilometres west of Red Deer, near Sylvan Lake. The earthquake occurred about a kilometre below the surface.
There were no immediate reports of damage, but power was knocked out for about 4,600 FortisAlberta customers. A spokesperson said the disruption lasted for a little more than an hour.
AltaLink said a transformer at a substation south of Sylvan Lake tripped around the same time of the quake. The transmission company is still investigating exactly what caused the outage.
The U.S. Geological Survey website says an earthquake similar to the one that struck Alberta has a sensation like a heavy truck striking a building; it can rattle windows and may break some dishes or windows.
Debbi McGillicky, who lives in the Mountain View area of Red Deer, said she and her husband were jarred awake by the quake.
“My husband and I were awakened at 5:55 a.m. when our bed began to shake violently. My husband shot up out of bed and exclaimed, ‘What the hell was that?’,” she told Postmedia. At the time, she thought the quake was some sort of explosion.
Linda Borsato lives in Sylvan Lake and said she was eating breakfast when the earthquake hit.
“There was a pop and the power went out, and right after the power went out the whole house shook from one end to the other,” she said.
“It was pretty freaky to say the least. We didn’t really know what to do when it first happened. . . It was enormous.”
Earthquakes are rare for the Red Deer area; the last recorded quake was in 2016. There was a 4.0-magnitude quake on March 31, 1997.
However, Joanne Gaudet, communications officer for the town of Sylvan Lake, said there has been seismic activity in the past between Sylvan Lake and Rocky Mountain House to the west.