Man-made earthquakesOhio town suffers 100 earthquakes as a result of shale fracking

Since records began in 1776, the people of Youngstown, Ohio had never experienced an earthquake. From January 2011, 109 tremors were recorded, and new research in Geophysical Research-Solid Earth reveals how this may be the result of shale fracking.

A Wiley release reports that in December 2010, Northstar 1, a well built to pump wastewater produced by fracking in the neighboring state of Pennsylvania, came online. In the year that followed seismometers in and around Youngstown recorded 109 earthquakes; the strongest being a magnitude 3.9 earthquake on 31 December 2011.

The study authors analyzed the Youngstown earthquakes, finding that their onset, cessation, and even temporary dips in activity were all tied to the activity at the Northstar 1 well. The first earthquake recorded in the city occurred thirteen days after pumping began, and the tremors ceased shortly after the Ohio Department of Natural Resources shut down the well in December 2011.

Dips in earthquake activity correlated with Memorial Day, the Fourth of July, Labor Day, and Thanksgiving, as well as other periods when the injection at the well was temporarily stopped.

— Read more in Won-Young Kim, “Induced seismicity associated with fluid injection into a deep well in Youngstown, Ohio,” Journal of Geophysical Research: Solid Earth 118, no. 7 (19 July 2013) (DOI: 10.1002/jgrb.50247)