A study by the BC Oil and Gas Commission that has linked hydraulic fracturing with swarms of small earthquakes is not likely to lead to any significant restrictions on drilling activity, according to industry and regulatory officials.
But new guidelines, increased seismic monitoring and more research will occur because of the investigation by the commission, which linked oil and gas activity in the Horn River Basin to a flurry of earthquake activity between 2009 and 2011.
Ken Paulson, chief operating officer for the commission, said the seismic events – triggered by fracking activities in which fluid was injected underground to fracture shale deposits and release gas – were all so small that only one of them was felt by people in the area.
Many were so small that they weren’t even picked up by federal seismic-monitoring stations, although they were recorded by dense arrays of sensors installed by researchers in some areas of the gas fields in northeast B.C.
Mr. Paulson said none of the 272 earthquakes recorded during the study period were of a magnitude large enough to raise environmental or public-safety concerns.
He said, however, that more research into the subject will be undertaken and closer monitoring of seismic events will take place in B.C.’s oil and gas fields.
“Anywhere you are inducing fault slippage you want to understand it and make sure that it’s controlled and you know exactly what’s happening so you have containment,” he said.
David Pryce, vice-president of operations for the Canadian Association of Petroleum Producers, said the industry has become increasingly aware of the issue over the past few years because of studies in the U.K. and U.S.
But he said the BC Oil and Gas Commission’s findings seem to be more definitive than anything he has seen before, and industry accepts a linkage has been established between its activities and localized earthquakes.
He noted, however, that the seismic events are all so small that with awareness about where existing faults are, and with attention to the pumping rate of fluids (faster pumping is more likely to trigger an event), future problems can be avoided.
“The OGC report comes out on the heels of a couple of other reports . . . all three say these are relatively low-energy seismic events . . . and if we operate according to regulations and good practices ... the risk [of a damaging event] is low to non-existent,” Mr. Pryce said.
He said although the earthquakes studied were all too small to cause any damage, industry is paying attention because the public is concerned about the issue.
“If we’re not doing that and the public isn’t satisfied that we’re doing a good job in that regard, then our social licence to operate is at risk, so we pay attention to that,” Mr. Pryce said.
He said CAPP will partner with Geoscience BC, an industry-led, non-profit geoscience organization, to provide an enhanced array of seismic monitors in B.C. gas fields to help record future events. The additional monitoring equipment is expected to cost more than $1-million.
John Clague, a professor of earth sciences at Simon Fraser University, said the commission’s study confirms a link between industry activity and seismic events that many had suspected.
“It doesn’t surprise me,” he said of the study. “Back maybe six months ago when this issue first came to public attention we had a look at the epicentres of a cluster of earthquakes that had been reported [in northeast B.C.] ... and in space and in time they were closely linked with hydraulic fracturing taking place in the Horn River Basin. So I think it kind of confirms what we already knew.”
Mr. Clague said the findings do not raise public-safety concerns.
“The interesting thing is you don’t seem to get big earthquakes and small earthquakes don’t necessarily lead to large ones,” he said.
Mr. Clague praised the commission for looking into the issue and for promising more research and regulation.
“The Oil and Gas Commission is doing the right thing. They are saying we need to look at this more closely,” he said.Report Typo/Error