From the Associated Press:
A newspaper analysis finds that the average number of 2.0 magnitude and higher earthquakes occurring in Ohio each year has risen.
The rise reported by The Columbus Dispatch coincides with an average increase in tremblors nationally and to an increase in oil-and-gas drilling and deep injection activity in eastern Ohio.
Ohio Department of Natural Resources data reviewed by the newspaper showed Ohio averaged two earthquakes annually of 2.0 magnitude or greater between 1950 and 2009. Between 2010 and 2014, that average rose to nine.
Nationally, earthquakes of magnitude 3.0 or higher averaged 100 annually between 2010 and 2012, compared to 21 annually from 1967 to 2000, according to the U.S. Geological Survey.
Up to five minor earthquakes recorded southeast of Youngstown last Monday and Tuesday are being investigated by ODNR.
The epicenter of the quakes is about two miles from th Hickory Bend gas-processing plant on the Ohio-Pennsylvania border.
Chesapeake Energy Corp,the Oklahoma-based firm is the No. 1 driller in Ohio.
Rig Count Interactive Map by Baker Hughes, an energy services company.
Shale Sheet Fracking, a Youngstown Vindicator blog.
The Ohio Environmental Council, a statewide eco-group based in Columbus.
Earthjustice, a national eco-group.
People's Oil and Gas Collaborative-Ohio, a grass-roots group in Northeast Ohio.
Concerned Citizens of Medina County, a grass-roots group.
No Frack Ohio, a Columbus-based grass-roots group.
Fracking: Gas Drilling's Environmental Threat by ProPublica, an online journalism site.
Pipeline, blog from Pittsburgh Post-Gazette on Marcellus shale drilling.
Allegheny Front, environmental public radio for Western Pennsylvania.