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.
Investor site StreetAuthority is gushing over the potential of other shale fields in the United States. It says one shale formation in particular now being explored in Texas could hold as much as 30 billion barrels of recoverable oil and fuel, dwarfing the estimated 4.3 billion barrels in North Dakota's Bakken shale.
Street Authority writes: "Devon's wells show that the formation contains 3.6 million recoverable barrels of oil per square mile. As the Cline is roughly 9,800 square miles in size, this works out to estimated reserves in excess of 30 billion barrels.
"These reserves could easily eclipse the Bakken (4.3 billion barrels according to conservative government estimates) and the Eagle Ford (3 billion barrels).
"Something I should point out here is that the numbers quoted above are subject to change, have changed often in the past and can vary wildly depending on your source."
Read the whole thing here.