Alberta Energy Regulator cites company for causing seismic events in Peace River area
The Alberta Energy Regulator has cited an energy company for causing a series of earthquakes, including the largest recorded tremblor in the province's history.
The environmental protection order issued against Obsidian Energy Ltd. Thursday came the same day a scientific paper was published showing those earthquakes were caused by industry activity -- not natural causes, as the regulator initially suggested.
In November, parts of Alberta near the northwestern town of Peace River were rocked by a series of quakes culminating in one that reached a 5.6 magnitude.
Residents reported being knocked to their knees. The earth was pushed upward by more than three centimetres - enough to register on satellites.
“This event was caused by wastewater disposal,” said Ryan Schultz, a Canadian seismologist who helped conduct the research while at Stanford University in California. His paper on the event, written with colleagues at the University of Alberta and Natural Resources Canada, was published Thursday morning in the journal Geophysical Research Letters.
In a release Thursday evening on Twitter, the energy regulator said the protection order was issued after its own investigation.
“An investigation conducted by the Alberta Geological Society, a branch of the AER, has concluded that Obsidian's disposal operation induced the seismic events,” it said.
Oilpatch techniques, such as deep disposal wells that inject wastewater kilometres underground, can induce earthquakes. One such well located near the earthquake site, used to dispose of water used in oilsands operations, has injected more thanone millioncubic metres of wastewater down about two kilometres.
After the record-breaking quake occurred, the Alberta Geological Society attributed it to natural causes. The centre of the quake, then estimated to be six kilometres underground, was thought too deep and too far away from oilpatch activity in time and space to have been generated by industry.
Not so, said Schultz.
A closer and more thorough look at the data brought the centre of the quake up to about four kilometres beneath the surface. At some point, the regulator's catalogue of Alberta quakes was changed to reflect that figure.
Similarly, Schultz said a look at previous research on so-called “induced seismicity” revealed long lag times between deep-well water injection and earthquakes.
A previous disposal site in Alberta started quaking three years after pumping began, Schultz said. A Dutch disposal well didn't start causing earthquakes for decades.
As well, history shows deep water disposal can cause earthquakes up to 20 kilometres away. Alberta's November earthquakes were nowhere near that distant.
“The clusters of earthquakes were right on top of a deep disposal well,” Schultz said.
His paper suggests that the injected water forced itself between the two sides of a fault deep in the earth. That water was enough to reduce the friction holding the two sides together and eventually resulted in a slippage that shook the surface.
Statistical analysis of the correlation between the quakes and the underground pumping was conclusive, Schultz said.
“We had a confidence somewhere between 89 and 97 per cent just in the timing,” he said. “There is enough information to start making these kinds of links.”
Schultz said the findings could have big implications for Canada's and Alberta's climate change plans.
Both jurisdictions favour reducing the climate impact of the province's energy industry by pumping vast amounts of waste carbon dioxide deep underground, much as wastewater is injected. So-called carbon capture and storage could have the same seismic effects as deep wastewater disposal, Schultz said.
“If carbon capture is going to be done at a scale that is going to combat climate change, then significant amounts of volume need to be put in the ground,” he said. “You might expect then also getting these types of earthquakes the more volume that you store.”
That doesn't necessarily mean carbon capture and storage is a bad idea, he said, but it means a lot more seismic monitoring needs to take place around the sites to keep track of what's happening deep in the earth.
“This could be an issue,” Schultz said. “Monitoring will tell.
“You need to be able to see what is going on.”
Obsidian now must submit plans and take actions to reduce the frequency and magnitude of the events, says the protection order, which covers the November quake as well as subsequent events on March 16.
The company, an oil and gas producer that pumps about 33,000 barrels of oil equivalent a day, must also establish seismic monitoring in the surrounding area and install equipment within a 10-kilometre radius of the disposal operation to measure vibration.
This report by The Canadian Press was first published March 23, 2023.
CTVNews.ca Top Stories
Deaths of 4 people on Sask. farm confirmed as murder-suicide
The deaths of four people on a farm near the Saskatchewan village of Neudorf have been confirmed a murder-suicide.
Multiple bridges in Calgary shut down for police incident
Calgary police have shut down a number of bridges into and out of the downtown core as officers deal with a distraught individual.
Sunshine list: These were the Ontario public sector's highest earners in 2023
Ontario released its annual sunshine list Thursday afternoon, noting that the largest year-over-year increases were in hospitals, municipalities, and post-secondary sectors.
Why some Christians are angry about Trump's 'God Bless the USA' Bible
Former U.S. President Donald Trump is officially selling a copy of the Bible themed to Lee Greenwood’s famous song, 'God Bless the USA.' But the concept of a Bible covered in the American flag has raised concern among religious circles.
George Washington family secrets revealed by DNA from unmarked 19th century graves
Genetic analysis has shed light on a long-standing mystery surrounding the fates of U.S. President George Washington's younger brother Samuel and his kin.
Baby boom amongst nurses leads to maternity ward closure in Listowel, Ont.
The emergency room at Listowel’s hospital is open today, but come summer, their obstetrics unit will be temporarily closing its delivery rooms.
Humboldt Broncos bus crash survivor qualifies Canada for Paralympics in rowing event
Former Humboldt Broncos goaltender and bus crash survivor Jacob Wassermann has qualified Canada for a rowing event for the 2024 Paralympic games in Paris.
Krispy Kreme doughnuts coming to McDonald's in U.S., but not Canada
Canadians will be missing out on a sweet new partnership between McDonald's and Krispy Kreme, which will see doughnuts available at McDonald's locations across the U.S. by the end of 2026.
'We won't forget': How some Muslims view Poilievre's stance on Israel-Hamas war
A spokesman for a regional Muslim advocacy group says Conservative Leader Pierre Poilievre's stance on the Israel-Hamas war could complicate his party's relationship with Muslim Canadians.