Research on the effect of injecting fracking wastewater on seismic activity in the state of Oklahoma has divided the U.S. scientific community. Seismologist researchers from the University of Oklahoma claim that disposing of produced water underground can trigger seismic activity, while the Oklahoma Geological Survey concluded that the series of earthquakes which led to the research happened because of natural causes.
In an interview for the Real News Network in Baltimore, Md., Dr. Elizabeth Cochran, a seismologist with the U.S. Geological Survey who worked on the research with the University of Oklahoma, explained that scientists looked into three separate earthquakes in 2011, with two of them having a magnitude of 5.0 and the third one having a magnitude of 5.7. These earthquakes occurred within 500 meters of injection wells, Cochran said.
Researchers believe that over the years of fracking activity in the area, the pressure of the injected produced water has been rising, eventually causing these quakes.
The Oklahoma Geological Survey stated that the so-called Prague Earthquake Sequence should continue to be studied, along with other analysis of current active seismic areas in the state Oklahoma. In addiction, improved earthquake monitoring and acquisition of formation pressure data are recommended for a more detailed picture of the causes of seismic activity, it said.