“After a few minutes, I realized it was an earthquake,” Langer said.
Jeff Gu, a seismologist at the University of Alberta, said the earthquake could have been caused by shifting rock formations in the region — but added there could be another possible explanation.
“Certainly that region is not immune to earthquake faulting, but I would say having actual earthquakes in that area is relatively recent, relatively new,” he said.
Gu is one of three authors of a recently published study in the Journal of Geophysical Research, a peer-reviewed publication that looked at four years of earthquake data around Rocky Mountain House. The study concludes that waste-water injection into the ground is highly correlated with spikes in earthquake activity in the area.
It is the first study of its kind conducted in Canada that links industrial activity to induced earthquakes.
“The conclusion was that the industrial activities could, in some cases, potentially trigger or facilitate earthquake occurrences,” Gu said.
Alberta earthquakes increasingSince 1985, fewer than 15 earthquakes above a 3.0 magnitude have been recorded anywhere in Alberta, according to the Alberta Geological Survey's website. There has been an increase in earthquake activity since the 1960s, the organization says.
The Peace River earthquake is not the only one that has shaken the province in the past few months:
- In October, a 2.7-magnitude quake was recorded about four kilometres southwest of Banff.
- In August, a 4.3-magnitude earthquake was registered near Rocky Mountain House, causing about 500 customers in the area to lose power for several hours.
“There has been more and more evidence, increasing evidence, in the last few years in particular — in Arkansas, in Texas and actually more recently here,” Gu said.