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.
A rash of earthquakes in the middle of the United States appears to be related to drilling for natural gas, according to researchers at the U.S. Geological Survey.
The surge in quakes "is almost certainly man-made," the scientists said in an abstract for their study.
Deep underground injection of drilling wastes appears the likely culprit.
The study found 50 earthquakes of magnitude 3.0 or greater in 2009 in an area from Alabama to Montana. That number grew to 87 in 2010 and 134 last year.
"This is very peculiar, what's going on," report author and geophysicist William Ellsworth told EnergyWire.
In Ohio, the Youngstown area has had 13 quakes in the last year near a now-closed injection well where brine wastes were pumped deep underground for disposal.
The paper is to be presented next month at a meeting of the Seismological Society of America in San Diego. The abstract has been released.
You can read the EnergyWire story here.