Chesapeake Energy Corp. is No. 1 in drilling in Pennsylvania's Marcellus shale, according to a report from Standrad & Poor's, the credit ratings agency.
The Oklahoma-based energy company has leasses on nearly 1.8 million acres in Pennsylvania.
The ratings are based on the volume of natural gas produced. There are two estimates for each of the Top 15 drilling companies.
Click here to see a story and chart from the Marcellus Drilling News.
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.