Fracking triggers 90% of large quakes in B.C., Alberta oil and gas patch

There's badnews and goodnews when it comes tofracking and earthquakes in Western Canada, according to new research from a paper co-authored by aGeological Survey of Canada scientist.

The new research confirms a definitive link between hydraulic fracturing and almost every large induced earthquake recorded in B.C. and Alberta's oil and gas patches since 1985.

In other words, scientists now have evidence that 90 per cent ofseismic events over magnitude 3.0that shook the region weretriggered by crewsfrackingfor oil and gasunderground.

But with so many fracking wells in operation,the evidence alsoshows only a tiny fraction of them less than one percent directly triggered earthquakes.

Now, scientists say, they need to determine what factors caused 39 wells to trigger quakes.

Mysterious factors

They say it appears other factors they don't yet fully understand must also be at play determining which fracking operations trigger earthquakes and which do not.

"It is important for us to realize that indeed hydraulic fracturing can induce earthquakes," said Honn Kao, a research scientist with the Geological Survey of Canada and one of 13 co-authors of a study, set to be published in the May-June issue of the peer-reviewed Seismological Research Letters, the journal of the Seismological Society of America.

Earthquakes are definitely part of the fracking risk...- Scientist Honn Kao

"But the evidence so far indicates there are other factors that may be important in this process as well, so that we cannot blame all the hydraulic fracturing operations for inducing big earthquakes," he said.

Kao said these other factors arelikely related to local geology, local hydrologyand the distribution of tectonic plates and fault lines, but more research is needed.

In British Columbia, where the government has pinned its financial future on ramping up frackingso it canexport gas as liquified natural gas, these research results will be closely analysed.

'Part of the risk'

"We realize induced earthquakes aredefinitelypart of the risk that may be associated with the development of the oil and gas," said Kao." That is a cause for so much concern from the regulators as well as the public."

"It's important to conduct more research to figure out the best balance between the protection of the public safety and the environment and the economic benefits of developing unconventional oil and gas.

"Wewill provide the necessary science and all the scientific analysis to the policy making process so collectively B.C. and Albertawill make the wise decision if they want to proceed [with fracking] or not," said Kao.

12,289fracked wells studied

Kao and his fellow scientists based their research on 25years of data on earthquakeactivity in a swathe of northeastern B.C.and western Alberta, called the Western Canada Sedimentary Basin,that'snot traditionally seismically active. They combed through data between 1985 and 2015 about seismic events larger than magnitude 3.0,as well as information from12,289hydraulically fractured gas and oilwells, and 1,000 fracturingwaste disposal wells.

The results? More than 90 per centof largeearthquakes were associated with nearby fracking operations.More than 60 per centof these quakes were linked to hydraulic fracture withabout 30 to35 per centcomingfrom disposal wells.Only fiveto 10 per cent of the earthquakes hada natural tectonic origin.

As well, just 0.3 per centof thefrackedwells triggered largeearthquakes. Andthose largeearthquakes didn't result in any injuries or significant damage.

It's really just a matter of time before we start seeing damage...- Lead study author Gail Atkinson

While thepercentages sound small, lead author Gail Atkinson of the University of Western Ontariosaidthat thousands of hydraulic fracturing wells had beendrilled every year in the region, increasing the likelihood of earthquake activity.

"We haven't had a large earthquake near vulnerable infrastructure yet," she said, "but I think it's really just a matter of time before we start seeing damage coming out of this."

Atkinson said the new numbers could be used to recalculate the seismic hazard for the region, which could impact everything from building codes to safety assessments of critical infrastructure such as dams and bridges.

"Everything has been designed and assessed in terms of earthquake hazard in the past, considering the natural hazard," she said. "And now we've fundamentally changed that, and so, our seismic hazard picture has changed."

Different fromU.S. frack 'quakes

The research also confirmeddifferences scientists have long suspected betweenCanada and the United States. In the U.S., induced earthquakes are most often linked to the underground disposaloffracking waste materials, rather than the fracturing process itself.

Hydraulic fracturing or "fracking" is a process that involves pumping a mixture of water, sand and chemicals underground at high pressure to fracture rock and release trapped natural gas.

Studies have linked fracking with earthquakes in the U.K., Oklahoma, Alberta, and in B.C.