Uh-oh. But remember, correlation does not imply causation: Fracking Tied To Unusual Rise in Earthquakes in U. S.
A spate of earthquakes across the middle of the U.S. is “almost certainly” man-made, and may be caused by wastewater from oil or gas drilling injected into the ground, U.S. government scientists said in a study.
Researchers from the U.S. Geological Survey said that for the three decades until 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.
Those statistics, included in the abstract of a research paper to be discussed at the Seismological Society of America conference next week in San Diego, will add pressure on an energy industry already confronting more regulation of the process of hydraulic fracturing.
“Our scientists cite a series of examples for which an uptick in seismic activity is observed in areas where the disposal of wastewater through deep-well injection increased significantly,” David Hayes, the deputy secretary of the U.S. Department of Interior, said in a blog post yesterday, describing research by scientists at the U.S. Geological Survey.
But before everyone panics, there are a few things to consider.
First, the evidence is still very scant. USGS scientists can only point to a coincidence between the location of the increased seismic activity and the proximity of newly-drilled deep injection wells used to dispose of water recovered from the process of hydraulic fracturing. Also, the use of disposal wells is itself tied to government regulations, which now prohibit the use of open air evaporation pits as a disposal mechanism for fracking wastewater. And there is no correlation between hydraulic fracturing wells themselves, and any observed seismic activity. Only wastewater disposal wells are cited in the study. Finally, the full report, which hopefully will be made public after its formal presentation next week, is still not available.
But I have to say that as a resident of Oklahoma who got rattled and rolled by a couple of good sized quakes a few months ago, I am more than a little concerned. The story notes that according to current seismic theories, a rapid increase in tremblors similar to what has been observed in the central US would either be the result of volcanic activity, or the result of a major shock. Neither has been observed by the USGS.
I guess the new rule for living in Oklahoma is that if the tornadoes and hail don’t get you first, the earthquakes eventually will.
