Oil and gas fracking operations in British Columbia’s Peace region were by far the main cause of 5,757 “tiny earthquakes” between 2017 and 2019 that would have gone unrecorded if researchers hadn’t been looking for them, according to a study published last month in the journal Seismological Research Letters.
“If we see some kind of connection in time and place between the operation and the occurrence of the earthquake, we can associate an occurrence of the earthquake with the fracking operation,” one of the study’s lead authors, McGill University geophysicist Alessandro Verdecchia, told CBC. On that basis, “the vast majority of them seem to be connected with hydraulic fracking operations.”
The McGill research team set up 15 earthquake monitors across the region over the three-year span, CBC writes. Their goal was to determine “the largest magnitude earthquake that can be created by fracking in the western Canada sedimentary basin, a region in northeast British Columbia that includes the Montney Formation, a shale gas area that’s home to nearly 3,000 production wells.”
The answer to the question matters because “large-magnitude events can produce larger acceleration and velocity of the ground and, of course, can produce larger damages to infrastructure,” Verdecchia said. In 2018, no damage was reported after a 4.5 magnitude earthquake in Fort St. John, but the shakes were felt as far away as Dawson Creek and Chetwynd, 75 and 135 kilometres away.
The researchers also want to know how far away from a fracking site an earthquake can occur—so far, CBC says, studies have uncovered incidents at distances of up to five kilometres. “This will be helpful for operators when they decide to start a fracking well, to begin operations, because they can more or less keep a distance, let’s say, from important infrastructures or populated areas,” Verdecchia said.