UPDATE 1-Chesapeake files for $1 bln share sale, stock down

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SAN FRANCISCO, Nov 26 (Reuters) - Chesapeake Energy Corp (CHK.N) gave itself the ability to sell $1 billion in shares, according to a filing on Wednesday, as the U.S. natural gas company seeks to shore up its cash position.

After closing 11 percent higher, shares of Chesapeake fell 3 percent to $19.65 in extended trading on news of the shelf offering that includes preferred stock. Chesapeake shares have lost nearly one-half their value in 2008.

The company plans to generate $2.5 billion to $3 billion through asset sales this quarter. On Tuesday, it said it closed the sale of 32.5 percent of its Marcellus Shale interest to Norway's Statoil (STL.OL) for $1.25 billion in cash and a further $2.125 billion over the next four years. (Reporting by Braden Reddall; editing by Jeffrey Benkoe)