Another rare case of fracking-caused earthquakes has jolted Ohio.
A new study connects some 400 micro-earthquakes near the town of Canton, in Harrison County, to hydraulic fracturing wells. The three wells operated from September through October 2013 in the Utica Shale. Ten of the quakes registered between magnitude 1.7 and magnitude 2.2, but the tremors were too deep to cause damage or to be easily felt by people, according to the study, published Oct. 14 in the journal Seismological Research Letters.
The new study is the second report this year of fracking-linked earthquakes from drilling in the Utica Shale. The shale is a rock formation that is deeper and closer than the Marcellus Shale to the crystalline basement rocks where faults are more common. In March, scientists with Ohio’s Department of Natural Resources (ODNR) shut down drilling at seven Utica Shale gas wells in Poland Township after fracking triggered two small earthquakes. The ODNR now requires monitoring of seismic activity at fracking sites near known fault lines, and reducing the flow of water if earthquakes begin to occur.