January 21 2015
Jillian Kay Melchior
Even the authors of the fracking-earthquake study think the reaction to it has gotten out of hand.
Despite the sensationalistic headlines and opinion pieces, fracking can trigger earthquakes only in very rare, very specific conditions, say the authors of the highly publicized study in this month’s Bulletin of the Seismological Society of America.
“It did seem like there were some folks who were trying to use this [study] as fuel to say we should ban fracking because it generates earthquakes,” says co-author Mike Brudzinski, a professor of seismology at Miami University in Ohio. “But earthquakes’ occurring during fracking is extraordinarily rare.”
Robert Skoumal, the primary author, tells National Review Online that he was concerned about the response as news of the report went viral: “Millions of people saw this [study], and the comment section was just a train wreck. People didn’t really see what we were doing, what we were arguing. . . . These are pretty small events, so an outright ban [on fracking] wouldn’t be appropriate.”
Skoumal and Brudzinski used a computer program coded in-house to correlate seismic activity and active fracking operations over time. Using high-tech seismic monitoring, they identified 77 small quakes near fracking sites around Poland Township. The largest was magnitude 3. “They say if you’re right on top of it, it’s like a milk jug falling off a counter, and that’s it,” says Eric Heis, a spokesman for the Ohio Department of Natural Resources, of this size quake. “A 3.0 is not a danger to anybody. It doesn’t even knock over a plate on a table,” he added.
Skoumal and Brudzinski tell NRO that the Poland Township scenario they recorded was freakish. Fracking had occurred right on top of small, preexisting faults, and shortly after fracking stopped, so did the quakes.
“In this case, there’s no evidence of wrongdoing by the operators of this well,” Skoumal says. “They just happened to be operating near a fault that’s very hard to detect. The conditions were ideal. They were just very unfortunate in this case.”
Brudzinski insists that, while there are hundreds of thousands of fracking sites worldwide, “just a handful” have ever been recorded to trigger quakes. (Another earthquake expert, Cliff Frohlich, tells NRO that he is aware of “maybe ten other instances on the planet” where fracking triggered an earthquake.)
“These seem to be very specific situations, and it seems to be only when you’re very close to one of these faults that’s sort of ripe. You could have many, many operations where you see no seismicity at all with fracking,” Brudzinski says. “The fracturing process itself rarely produces earthquakes.”
The earthquakes that Skoumal and Brudzinski recorded correlated with fracking operations less than half a mile from the fault. Around a hundred other fracking sites operated just a bit beyond the half-mile mark, Brudzinski says, and “they didn’t produce any recordable earthquakes.”
The higher earthquake risk actually involves what happens after fracking, Brudzinski says. Some companies pump the wastewater back underground, which can lubricate stone-on-stone stress, unleashing a pent-up earthquake. “To help you understand the rock-on-rock [tension], think of it as a really rough surface, almost like it has teeth,” he explains. “In a regular earthquake, basically, the stresses on both sides of the fault have to be big enough to break the teeth. . . . But if you put water in there, the two sets of teeth don’t have to touch and can slip.”
There’s a much stronger correlation between this wastewater-disposal process and earthquakes, but calling it “fracking” isn’t accurate, according to Brudzinski.
The appropriate response to their study, Skoumal and Brudzinski say, is not to ban fracking but to do more research and better monitor where faults might rest. In the rare event that a fracking site sits on a fault, or if small earthquakes begin in the immediate vicinity, state officials and energy companies, they suggest, should consider stopping and moving operations a bit farther away.
“At this point, there’s not a lot of rationale for huge changes in how the industry is fracking,” Brudzinski says.
— Jillian Kay Melchior writes for National Review as a Thomas L. Rhodes Fellow for the Franklin Center. She is also a senior fellow at the Independent Women’s Forum.