Youngstown, Ohio, experienced its very first earthquake in January 2011. From then until February 2012, it experienced 108 more. According to research published in the Journal of Geophysical Research, the sudden wave of quakes, unheard of since Ohio began keeping records in 1776, was likely tied to hydraulic fracturing, or fracking.

Specifically, the study points to the December 2011 installation of a wastewater disposal well in neighboring Pennsylvania. According to the researchers, the quakes’ ‘onset, cessation and even temporary dips in activity