Occidental Petroleum Corp on Thursday said it signed a deal to sell its interests in a natural gas field that sprawls across three states to an unnamed buyer for a pretax price of $1.4 billion.

The Los Angeles oil and gas developer, which has been selling off non-core assets, said proceeds would be used to buy back shares.

The Hugoton Field spans southwestern Kansas and parts of Oklahoma and Colorado. Occidental’s interest comprises more than 1.4 million acres.

Shares closed up 8 cents, or less than 1 percent, to $92.27 on the New York Stock Exchange.