Devon Pictures Blue Horizon

When energy experts skimmed a mid-November drilling report for East Texas, one well immediately jumped out.

The well, drilled by Devon (DVN Quote) in the Freestone Trend of the Cotton Valley, reported initial production of some 23.3 million cubic feet of gas per day. While some vertical wells in the same region deliver plenty of gas, none looks nearly as promising as that Cotton Valley standout.

Harry Chernoff, a principal at Pathfinder Capital Advisors, did some math. The new well looked poised to deliver four to five times as much gas as one of Devon's successful vertical wells in the same region. Thus, he concluded, this one had to be a horizontal well instead.

Chernoff was right. Devon confirmed for TheStreet.com this week that the well is in fact a horizontal -- signaling yet another breakthrough for Devon and smaller players, such as GMX Resources (GMXR Quote), hoping to follow its lead. If the horizontal wells pan out as planned, experts say, the Cotton Valley could soon offer greater drilling opportunities than any other region in the country.

Big payoffs for investors could follow. Horizontal wells promise lower finding costs and greater gas recoveries per acre -- translating into higher profits -- for Cotton Valley players.

"This is huge," Chernoff says. "It's in everybody's presentations now."

Devon's stock slipped 36 cents to $72.88 on Wednesday, leaving it near the top end of its 52-week range.