CALDWELL, Ohio — The energy boom has swept into the rural counties of the upper Ohio River Valley, producing a torrent of investment in mineral leasing that is jolting the economies of small towns and swelling the bank accounts of some working-class families.

Here in Noble County, where vehicle repair and convenience stores are economic mainstays, Eclipse Resources, a Pennsylvania company, mailed $16 million in oil- and gas-leasing checks last month to 70 households whose property has been found to sit atop oil and gas reserves. Working with a lawyer in nearby Marietta, the residents were able to band together to negotiate an unusually lucrative deal with the company that paid $4,000 an acre and 19 percent royalties on oil and gas production, and included safeguards to protect water and land. (The standard has been $20 to $30 an acre, one-sixth royalty rates, and no protections for water and land.)

In a region where median household income is less than $33,000, the first big flush of oil- and gas-related income produced leasing checks of six and seven figures — amounts the recipients say are a bit disorienting.