HOUSTON — Chesapeake Energy Corp. is selling oil and gas assets in Colorado and Wyoming as it seeks to raise revenue to fund its cash-strapped operations.

According to a prospectus listed by the transaction-advisory firm helping Chesapeake, about 503,863 net acres of land in the northern DJ Basin are being listed. The area includes both conventional and unconventional reservoirs. Last year, Chesapeake sold acreage there to China’s Cnooc Ltd.

The move is part of Chesapeake’s bid to raise up to $11.5 billion from the sale of assets this year to help pay down debt and run its expensive drive into oil-rich shale areas. The company recently said it would seek to divest noncore assets in addition to the widely announced sale of its oil-rich land in the Permian Basin and the listing of a joint venture in the Mississippi Lime in the central U.S.

Analysts have said they are concerned about the company’s liquidity, which has been sapped by decade-low levels for natural-gas prices, by its high levels of debt and by the steep requirements of its drilling program.