It's unclear who owns the minerals underlying much of Ohio's state park system, according to this article in the Columbus Dispatch. "Of the 115,300 acres of state parks, the Ohio Department of Natural Resources estimates that it owns the gas rights for 34,590 acres. That's less than one-third of the state park land that could be opened to drilling if lawmakers approve one of several proposals."
Interesting. And a good map illustrating the issue.