CALGARY
Hydraulic fracturing may be to blame for a number of moderate earthquakes in western Canada, according to a study released March 29.

A recent study conducted by a group of Canadian geoscientists found increased earthquake activity in the Western Canadian Sedimentary Basin, which hosts the Montenay and Liard Basin natural gas deposits, could be the result of hydraulic fracturing. - photo courtesy of Wikimedia Commons

The study, conducted by a team of Canadian geoscientists, examined data from 12,285 hydraulic-fracturing - or fracking - wells and 1,236 waste-water wells along a 454,000 square-kilometre section of the Alberta/British Columbia border. By tracking the location and time of historical seismic activity, researchers were able to determine which earthquakes were most likely caused by the controversial industrial activity.

They found 39 of the fracking wells and 17 of the waste-water wells "could be" linked to earthquakes of magnitude three or higher - a relatively small percentage, but the authors say as more wells are added to the basin and fracking activities increase it is "only a matter of time before we start seeing damage come out of this."

Study co-author David Eaton, a geoscientist at the University of Calgary, studied seismic activity caused by humans. He said the report basically confirmed what he and his colleagues had suspected for a number of years and brought to light an issue associated with shale gas development which has largely gone undocumented.

"There's not really a tremendous amount of good information available to the public about this topic," he said, adding most concerns and studies around fracking have focused on groundwater contamination and greenhouse gas emissions.

He said although the study's findings are concerning, more work needs to be done to gain a better understanding of the relationship between fracking and earthquakes. Future research will examine why some areas of the basin are more vulnerable than others, Eaton said, since at this stage the fraction of quakes per well was minimal - only a fraction of one per cent caused seismic activity.

"(We want) to really understand the "why" question - specifically what are the risk factors that make some areas more prone to induced seismicity than most areas where hydraulic fracturing takes place," he explained. "And also to better understand mitigation, if an induced earthquake is triggered by fluid injection, then what are the most appropriate steps to take."

During the process of hydraulic fracturing or "fracking", water is injected into the ground at a high pressure, breaking shale rocks to release the natural gas trapped inside.

This increased pressure causes the quakes. Although most of the occurrences studied since 1985 have been small to moderate in magnitude, a large event could occur if fluid finds its way "to a suitably stressed fault," the report states.

In March, results of a three-year study on the resource potential of the Liard Basin were released, revealing its natural gas deposits were some of the largest in the world and Canada's second-largest after the Montenay formation. However, the resource would require fracking to extract.

During the 17th Legislative Assembly in 2015, former Yellowknife MLAs Bob Bromley and Robert Hawkins put forward a motion to temporarily ban the practice in the territory until further studies on its environmental impacts could be completed. The proposal was ultimately shot down because dissenting MLAs and cabinet believed it would hurt potential economic development and job creation in the territory.

Drew Williams, spokesperson for the Department of Industry, Tourism and Investment told News/North in an e-mail there have been too many conflicting studies around issues related to fracking to warrant comment on the report's findings.

"There are varying viewpoints and studies that have been brought forward on the practice of hydraulic fracturing. Without a thorough understanding of the objectives and methodologies incorporated, it would be inappropriate to comment or evaluate the findings of a particular study," he said. "Residents of the NWT can, however, be assured that through its (departments), the GNWT is committed to safe and responsible development of its resources."

Eaton said because the territory's resources are still largely undeveloped, the NWT is in a unique position - able to observe studies and phenomena happening elsewhere and then modify its regulations and practices accordingly.

"I think the NWT is in an enviable position in as ... there has been relatively little development of the resource so far," he said. "This means the territory can benefit from learning that takes place down south and then proceed cautiously but enlightened."