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.
The Marcellus Shale News and a newspaper in Coshocton report that the Ohio Department of Natural Resources' Division of Geological Survey intends to release a new map of Utica shale potential in Ohio.
That map is due to be released in September.
It reflects new and promising core sample data in central Ohio.
The samples from Crawford, Knox, Marion, Seneca and Wyandot counties show promise, said Ohio state geologist Mac Swinford.
He identified an area that runs north-south just west of Columbus as showing great potential.
The problem is whether the oil has been fully developed below ground and whether there is enougbh pressure to bring it to the surface.
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