Experts with the U.S. Geological Survey and other seismologists have directly linked recent earthquake activity in Ohio and Oklahoma to nearby hydraulic fracturing (fracking) activity. MSNBC.com reports a geophysicist with the survey based in Menlo Park, Calif., confirmed a relationship between recent minor seismic activity with the injection of waste fracking fluids into underground wells.
The most recent earthquake in Ohio occurred on Dec. 31 near Youngstown and registered 4.0 on the Richter scale. It prompted local officials to order several injections wells to close and stopped any fracking drilling near the well. That quake was the last of 11 recorded in Ohio in 2011 and experts believe there will be more tremors through this year even if the wells remain closed and fracking is halted.
The report indicates officials near Oklahoma City are investigating a possible link between a 5.6 earthquake last year and nearby fracking activity. Fracking has been the suspected culprit behind thousands of earthquakes across the country, most frequently in Arkansas, West Virginia and California.
Epicenters of the Ohio quakes are not in particularly seismic areas but the Geological Survey believes the high-pressure injection of waste fracking fluid is working to trigger earthquakes that were possibly bound to happen. The briny nature of the waste fracking fluid is believed to be either splitting underground rock and causing faults to slip and trigger the tremors or wearing down rock, creating minor faults which slip and cause earthquakes.
How waste fracking fluid injected into underground wells causes the earthquakes is not known for certain but the timing of fracking activity, subsequent earthquakes and the probability of earthquakes in a particular area, specifically in Ohio, led the seismologists and geophysicists interviewed by MSNBC.com to draw the same conclusion, that fracking drilling causes earthquakes. Earthquakes are likely even after drilling and disposal is halted as underground rock continues to settle. It is not known if earthquake magnitude will increase if fracking activity and the use of underground injection wells continues.
Not every state dealing with fracking experiences earthquakes but that doesn’t make the process any safer. If anything, the earthquakes are just an added danger. Fracking has already been suspected of causing widespread and localized contamination of underground water supplies, contaminating thousands of private water wells in states where fracking is conducted. At the moment, much of the activity is in the Mid Atlantic and the massive Marcellus shale formation, which stretches from Ohio to New Jersey.
The problems encountered with underground injection wells seemingly presents one less option for states dealing the problem of disposing of waste fracking fluid, such as Pennsylvania, which attempts to treat waste fracking fluid and eventually recycle it. Studies on that process have determined all but one water treatment plant in that state were able to properly treat waste fracking fluid before it could be taken to a public facility, where it would eventually be released back into the public drinking supply.