One of three earthquakes that gently rocked a small northern Alberta oil town this year may have been the strongest seismic event ever caused by fracking, worldwide.
The shale fields around Fox Creek used to get one, maybe two, small earthquakes per year. Since 2003, when fracking companies began setting up shop in the nearby Duvernay formation, that number has shot way up. A 2015 study said 160 minor earthquakes have been detected since then, nearly all of them clustered around fracking operations. This year, scientists say, the tremors have started breaking records.
But local residents aren't revolting against hydraulic fracturing, which has revolutionized fuel extraction in North America, particularly in North Dakota and Texas.
The technology, which injects pressurized water into wells to free up hard to reach fuel deposits, has increased US oil output by more than two million barrels per day. With about 12,000 wells, Alberta and British Columbia are home to the overwhelming majority of Canada's fracking operations.
In January, a 3.8 magnitude earthquake struck about an hour west of Fox Creek. It was followed a week later by an even stronger quake that reached 4.4 on the Richter scale. Both of those fit neatly into the 'minor' to 'light' range of the scale, strong enough to be felt for dozens of miles, but too weak to cause structural damage.
Several weaker tremors followed, before another earthquake with a reported magnitude of 4.4 hit on June 13, 3 miles west of Chevron Canada's fracking well close to the town. Researchers later downgraded it to 4.0. Honn Kao, a seismologist with Geological Survey of Canada, says all the evidence points to fracking as the cause.
"Based on the depth, the location and the time, it seems very possible that it is related to these fracking operations," he told VICE News. University of Alberta seismologist Jeff Gu agreed, calling the connection "very probable."
Though measurement is always somewhat uncertain, Kao hasn't heard of any stronger earthquakes that have been connected to fracking, anywhere.
"It's not only in Canada or North America, it's actually around the world. These are the largest hydraulic fracturing-related earthquakes," he said. "It's the new world record."
Alberta's energy regulator passed new guidelines after the January quakes, forcing industry to report seismic activity and shut down their operations for anything over 4.0 magnitude. Chevron stopped fracking for two weeks after the June quake. On June 29, the regulator gave it the go-ahead after concluding that the company had made acceptable changes.
Fracking involves drilling a horizontal well along a shale gas formation, and then injecting high-pressure water, chemicals and sediment to crack up rock and ease the flow of oil and gas. The process inevitably causes extremely weak micro-earthquakes, but can also exacerbate existing faults, triggering much stronger seismic events.
"The general theory is that there are faults in the region of the hydraulic fracturing operation, and as you pump large amounts of fluid underground, the presence of fluid could increase the chances of slippage on a fault," Gu explained. "It does not take much for faults that are pretty much ready to slip — the fluids will facilitate that slippage."
Fracking has been controversial across the country, with Québec and New Brunswick even placing temporary bans on the technology. Most criticism has focussed on the enormous amounts of water the process consumes and the chance that toxic chemicals could seep into drinking water supplies. A study this year found that people who live close to fracking wells were more likely to be hospitalized for heart and skin problems.
But local residents are shrugging their shoulders about the earthquakes in Fox Creek. Most said they didn't even notice them, and no one wants to see profitable companies like Chevron close their doors.
Stacey Campbell, who manages the Silver Birch Golf Club, told VICE News that she didn't feel this year's tremors, and hasn't noticed any damage to the town. She says Fox Creek depends on the energy sector for jobs.
"Yeah, the oil and gas companies probably had something to do with it, but what are we supposed to do?," she asked. "We need oil and gas."
Campbell says people should pay more attention to the rising epidemic of fentanyl addiction in the work camps outside of town.
"I think our drug problem is more important than earthquakes," she told VICE News.
On the other side of town, a worker at the Timber Ridge Inn & Suites said the recent quakes don't compare to what she's used to in her home country, the Philippines.
"If it's not 5.0, it's not really much for me," she said.
Roy Dell, Fox Creek's chief administrative officer, says the town is taking precautions and cooperating with the oil and gas industry to make sure things don't get any worse.
"Council is definitely concerned, and they are watching to see what's going on," he told VICE News. "We're concerned with the infrastructure of the town as well as the safety of the residents. When you start getting earthquakes you're afraid that things are going to break."
But that doesn't mean he's blaming the energy sector, which remains the town's economic lifeblood.
"Fox Creek is definitely an oil, gas and forestry town," he said. "I don't think industry would do something to put the townspeople in jeopardy."
Kao agrees that Fox Creek is probably safe. Since earthquakes weren't unknown before fracking, the city's infrastructure can probably handle the increasing frequency of somewhat stronger tremors. But it wouldn't be wise to start fracking in areas that had never seen much seismic activity.
"In a seismically active zone where you have a magnitude 4, that's no big deal," he said. "But in a place where you usually have magnitude 2, and then suddenly you have magnitude 4, thats a big deal."
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