The US Geological Survey (USGS) folded to pressure from the fossil fuel industry and pro-fracking Congress members last week by releasing a “more study needed” r
eport on fracking and earthquakes. The stakes are simply high enough that the agency is unwilling to strongly state the obvious. The report to Congress says, “ Keep fracking, these earthquakes are no big deal.”
For example, in northeastern Ohio, where the boom is in full swing, seismic instruments recorded nearly a dozen small quakes in 2011, with a magnitude-4.0 tremor reported December 31.
The quakes prompted state officials in January to order four fluid injection wells in the eastern part of the state to be “indefinitely” prohibited from opening.
John Armbruster of Lamont-Doherty Earth Observatory, Columbia University, who hass been studying seismic events and fracking in the Youngstown area for months, said on Friday that it’s “virtually certain” that an injection of fracking wastewater caused the New Year’s Eve tremor.
Depending on its location, “any disposal well that’s been pumping stuff into the ground for months can cause earthquakes,” said Armbruster, who’s studied earthquakes and drilling for 40 years.
Even the notably non-committal USGS report states “”Hydraulic fracturing in a well for shale gas development, which involves injection of fluids to fracture the shale and release the gas up the well, has been confirmed as the cause for small felt seismic events at one location in the world,” the report states. It found small seismic events involving “a very limited number” of injection wells, but the long-term effects of the growing number of wells wasn’t known.
In general, shifting the balance of fluids underground – whether taking more out of the ground than is put back in or vice versa – is likely to trigger seismic activity, the report concludes.
“While the general mechanisms that create induced seismic events are well understood, we are currently unable to accurately predict the magnitude or occurrence of such events due to the lack of comprehensive data on complex natural rock systems and the lack of validated predictive models,” the report states.
The USGS acknowledges that increased seismic activity coincides with wastewater injection. But it does not say there’s proof of a direct connection.
“While it appears likely that the observed seismicity rate changes in the middle part of the United States in recent years are manmade, it remains to be determined if they are related to either changes in production methodologies or to the rate of oil and gas production,” wrote David J. Hayes, deputy secretary of the U.S. Department of the Interior, which oversees the USGS.
“That’s too weak,” Armbruster said told CNN‘s Matt Smith and Thom Patterson. “In the case of Youngstown, the chance that this is just a random coincidence is like winning the lottery. It’s a million to one that it’s just a random coincidence.”
The USGS researchers found that, for three decades prior to 2000, seismic events in the nation’s midsection averaged 21 a year. They jumped to 50 in 2009, 87 in 2010 and 134 in 2011, according to the study, which was presented April 18 at the annual meeting of the Seismological Society of America.
Last year, Arkansas regulators permanently shut four disposal wells in the Fayetteville Shale after an outbreak of earthquakes near the town of Guy, including one that measured 4.7 on the Richter scale. This year, the state Oil and Gas Commission adopted rules requiring drillers to provide information on the structural geology of well sites and to position wells away from known faults, according to Lawrence Bengal, commission director.
“The circumstances under which these events occurred show there’s a very good relationship between these four disposal wells and the seismic activity,” Bengal said in an interview with Bloomberg.
The research council report shows that most of the tremors that can be blamed on humans occurred in the states of California, Texas, Colorado, Oklahoma, and Ohio. Colorado has one of the most documented cases of three 5.0 to 5.5 man-induced quakes because of a fracking waste-water injection well.
Left out of the study were man-made earthquakes this year, including induced quakes of magnitude 4 or larger in the past year in Texas, Oklahoma, Arkansas, Colorado, New Mexico, and Ohio, but the USGS authors said much of this conveniently happened too late for the research council to include in its study.