Ohio has experienced a surge in earthquakes in recent years, an uptick that corresponds with an increase in fracking in the state, according to a new analysis.
The Columbus Dispatch looked at data from the Ohio Department of Natural Resources and found that, between 1950 and 2009, Ohio saw an average of two greater than 2.0 magnitude earthquakes each year. Between 2010 and 2014, when fracking operations began to take off in the state, that number jumped to an average of nine per year.
That’s an uptick in earthquakes that’s been mirrored nationally, the analysis found. Between 2010 and 2012, the U.S. experienced an average of 100 magnitude 3.0 or higher earthquakes each year, compared to the 21 the country experienced each year between 1967 and 2000.
The analysis was prompted by a spate of earthquakes over the last few weeks in Ohio. Last week, five earthquakes were recorded in a 25-hour period near the town of Poland Township in Mahoning County, Ohio, an area that before a few years ago hadn’t seen a sizable earthquake in 100 years, according to the Columbus Dispatch. The earthquakes prompted a shutdown of a nearby fracking operation while scientists work to figure out whether the operation caused or contributed to the earthquakes. Officials with Columbia University’s Lamont-Doherty Earth Observatory say that those five earthquakes are part of a string of 11 1.2 to 3.0 magnitude quakes felt in the Youngstown, Ohio area between March 4 and 10.
The fracking process has been linked before to earthquakes in the Youngstown area. In 2012, a disposal well in Youngstown was shut down after scientists suspected that fracking waste injected deep into the ground may have caused a fault to slip.
It’s also been linked to earthquakes in other states. A December study from Southern Methodist University linked a string of 2009 and 2010 earthquakes in Texas to the injection of fracking wastewater into the ground. Cleburne, Texas experienced more than 50 earthquakes in 2009 and 2010 — before 2008, the Fort Worth Basin of Texas had never experienced an earthquake.
Wastewater injection has also been confirmed by the U.S. Geological Survey as a possible earthquake trigger. However, officials say that the recent earthquakes in Ohio were not related to wastewater injection, and are instead looking into whether fracking itself is related to the earthquakes. If fracking is determined to have caused last week’s earthquakes in Ohio, it would be the first time that fracking — and not waste disposal — was linked directly to earthquakes