In the past ten days, the North American oil and gas industry has rocked key geological formations with earthquakes in British Columbia and Texas.
Damage from the US quake, the third largest in Texas history, shut down a large building in San Antonio and showed that fracking-induced tremors can threaten structures even hundreds of miles from the epicenter.
Beginning November 11, Canada’s Montney Formation, a major source of methane and natural gas liquids between BC and Alberta, experienced three earthquakes measuring greater than four on the Richter scale.
Shocks greater than three can be felt, while those greater than four can knock items off shelves and, in rare cases, cause damage to structures.
On November 11, a magnitude 4.7 earthquake struck 90 miles north of Fort St. John in northeastern BC. The province’s fracking regulator, the BC Oil and Gas Commission, told the Tyee that drilling by Malaysia’s Petronas triggered the quake and a host of others. As more earthquakes followed, Petronas’ operations were halted, but then resumed before being halted again when another quake with a magnitude greater than four struck on November 15.
Meanwhile, the US fracking industry most likely triggered a 5.4 magnitude earthquake on Nov. 16 in the oil-rich Permian Basin of west Texas. The strongest earthquake in Texas since 1995 shook the Mexican city of Ciudad Juárez, 320 kilometers away. In San Antonio, 560 kilometers from the quake’s epicenter, structural damage inflicted on a historic five-story complex on the city’s university health campus prompted the closure.
After yesterday’s earthquake near Pecos, Texas, civil engineers have determined the downtown Robert B. Green Historical Building is unsafe. This building has been cordoned off and a security zone established around it. We will keep you informed of this situation. pic.twitter.com/E9FhETZE55
— University Health (@UnivHealthSA) November 17, 2022
The Railroad Commission of Texas — which largely self-regulates the Texas oil and gas industry — acknowledges that injecting saline sewage deep into the ground has increased seismicity in the region by putting pressure on nearby faults.
Since 2018, industry fracking and sewage works in the Permian Basin have caused thousands of earthquakes with magnitudes greater than 2.5.
Over the past 15 years, fracking in the Montney Formation has altered seismic patterns in the region and is now responsible for 70 percent of earthquakes. The industry triggered thousands of small tremors, and then gradually triggered larger-scale tremors, such as the 4.6-magnitude Canadian Natural Resources Ltd. tremor that struck the under-construction Site C dam in 2018.
How fracking triggers earthquakes
The shale gas industry injects high-pressure fluids and sand into deep and shallow wellbores to fracture oil and gas deposits trapped in dense rock formations. This fracking creates a network of fractures that may also be associated with water zones, other drill sites, and industry faults.
Reactivation of these faults can then trigger earthquakes, sometimes days after fracture treatment, scientists say.
Fracking operations also often take the wastewater they produce and inject it underground, which can similarly destabilize a geological formation.
For more than a decade, the two technologies have caused earthquakes that damaged infrastructure at fracking zones and even killed citizens in China.
The fact that fracking can unpredictably trigger tremors dozens of miles away has stymied regulators. Tremors caused by saline discharge can last 12 to 18 months even after activity has been suspended.
In British Columbia, the three Petronas-triggered quakes occurred in a remote area near Pink Mountain, and there were “no reports of damage,” National Resources Canada said on its website.
Under OGC’s drilling and production regulations, companies must stop fracking operations if they cause a magnitude 4.0 earthquake.
However, the Oil and Gas Commission says its seismic monitors recorded different magnitudes than Natural Resources Canada, beginning with a quake measured at 3.75 on Nov. 11 and a level four quake four days later.
The commission told The Tyee that the operator suspended operations on the suspect well for 24 hours after the November 11 event to allow the build-up of energy from the fracking operations to dissipate. But after operations resumed the next day, “a second event was logged (ML 3.3) on the evening of November 12 and operations on the subject well were suspended until November 13, 2022,” a spokesman said in an E- Mail.
When a 4.03-magnitude quake struck the same area on Nov. 15, fracking operations were suspended again in accordance with the commission’s rules, the spokesman said. “The permit holder had to submit a new operational plan to further reduce and/or eliminate incidents from the operation. This plan is currently under review by the Commission,” the email reads.
When asked if the regulator was concerned that the same company, Petronas, also triggered a magnitude 4.6 quake in 2015, the spokesman replied that the commission was “concerned about any events caused.”
“A subject of paramount importance”
A year ago, Allan Chapman, a former senior geologist with the Oil and Gas Commission, warned in a scientific paper that stress changes caused by fracking could trigger a magnitude five or greater earthquake in the region, causing damage to dams, bridges, pipelines and cities if important regulatory and policy reforms are not implemented soon. “Just because a high-magnitude event has a low probability of occurring doesn’t mean it doesn’t have a probability of occurring,” Chapman told The Tyee.
“We can look at the billions of dollars in damage in the Abbotsford, Merritt and Princeton areas and the tragic deaths related to extreme rain and flooding in November 2021 to understand the horrific impact of the government’s failure to address known hazards.”
Chapman added that the province’s experimentation with unconventional shale development and large-scale hydraulic fracking “has given Northeast BC the sobering distinction of having caused some of the largest fracked earthquakes in the world. It is an issue of paramount importance.”
Fracking appears to have a cumulative effect on geological formations as the technology injects more and more fluid that changes the pressure in the formation over time.
Based on Oil and Gas Commission data, fracking triggered 38 earthquakes greater than three on the Richter scale between 2020 and 2022, averaging 13 per year.
That’s an increase from the previous seven years, when the industry caused 56 earthquakes with a magnitude greater than three.
That 60 percent increase, Chapman said, “might indicate the cumulative effect of the tailcoat fluid injection.”
The fracking industry has had a dramatic impact on geologies, water availability and landscapes wherever it has been permitted. In Patagonia, Argentina, which is now the scene of intense fracking, the industry has triggered magnitude four and five earthquakes near active wells. The production of methane then caused the ground to sink.
In the Permian Basin, which includes large parts of Texas and New Mexico, researchers have reported that 68 percent of earthquakes greater than 1.5 are due to “hydraulic fracturing or the disposal of produced formation water into either shallow or deep geologic formations.” The region is poised to become the US earthquake capital
A recent University of Waterloo study assessing the fragility of the Montney Formation between Alberta and BC found that some areas are highly vulnerable to earthquakes triggered by fracking or sewage injection and concluded that “ it appears that most fault planes in the Kiskatinaw area and northwest Montney formation would become unstable with only a modest change in pore pressure.”
The seismic problems in the vast Montney region and global examples of the type of structural damage seen in Texas last week are at the root of conflicts over where and how fracking operations should be conducted. Chapman isn’t alone in raising concerns that without more oversight and restraint, fracking could eventually trigger a devastating earthquake in western Canada.
TransAlta Corp., the owner of Alberta’s largest hydroelectric dam south of Edmonton, is currently suing the Alberta government and the Alberta Energy Regulatory Authority for issuing permits that allow the industry to frack five kilometers near its dam.
TransAlta alleges in court documents that the Alberta government “has failed to develop, implement or enact clear policies that would protect Brazeau’s storage and energy development from ‘unacceptable’ risks posed by hydraulic fracturing in the immediate vicinity.”