What's the Latest Development?
A study that appeared in a recent issue of Geophysical Research Letters reveals that each of the 109 earthquakes that took place in or near Youngstown, OH in 2011 was linked to activity associated with the nearby Northstar 1 injection well. The well went online at the end of 2010 and was shut down at the end of 2011 after a magnitude 3.9 earthquake occurred. Interestingly, "dips in earthquake activity lined up with Memorial Day, the Fourth of July, Labor Day, Thanksgiving and other times when injection at the well was temporarily stopped."
What's the Big Idea?
While it's not the first time fracking and its outputs have been linked to seismic events, the persistence and regularity of such events in an area that had no records of earthquake activity in over 230 years is unique. Seismologist Won-Young Kim says that the Northstar 1 well was located in an ancient fault, which was ruptured by the wastewater injection. However, he notes that of the 177 other injection wells operating in Ohio during 2011, only this well was linked with seismic activity, and that, rather than change the overall disposal method, companies should "find better ways to image hidden subsurface faults and fractures."