Chesapeake Energy shares jumped after the natural gas producer announced plans to expand drilling and boosted its production forecasts.

The Oklahoma City-based company says 2008 output should rise 21 percent over last year's total, to equal 2.37 billion cubic feet of natural gas. Output in 2009 is likely to grow another 16 percent.

Chesapeake also laid out plans to explore for oil in four states, and said its Haynesville Shale site in Louisiana "could potentially have a larger impact on the company" than any previous project.

"The success seen in the Haynesville is positive not only for Chesapeake but for others that are active in the area," such as Cabot Oil & Gas, said Goldman Sachs analyst Brian Singer.

Chesapeake shares rose $1.39, or 3.1 percent, to close at $46.40.