ME Mariner Energy Inc.

Mariner Energy, Inc. (NYSE: ME) announced today that the company has acquired 100% working interest in approximately 54,000 net acres in the Denver Julesburg Basin (DJ Basin) from an undisclosed third party. Financial terms of the transaction are confidential.

The acreage comprises fee, state and federal leases located in Southern Wyoming in Laramie County. Mariner believes the acreage is on trend with and contains shales with petrophysical properties similar to the commercial Niobrara Shale discoveries of the Jake 2-01H well and Silo Field.

"This acquisition is consistent with our stated strategy of obtaining sizeable low-entry-cost oily shale plays where we can operate. The acreage is close to existing infrastructure, facilitating development if our exploration efforts are successful," said Scott D. Josey, Chairman, Chief Executive Officer, and President of Mariner Energy.

About Mariner Energy, Inc. Mariner Energy is an independent oil and gas exploration, development, and production company headquartered in Houston, Texas, with principal operations in the Permian Basin, Gulf Coast and the Gulf of Mexico. For more information about Mariner, visit the company's website at www.mariner-energy.com.

Important Information Concerning Forward-looking Statements

This press release includes forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. All statements, other than statements of historical facts, that address activities that Mariner assumes, plans, expects, believes, projects, estimates or anticipates (and other similar expressions) will, should or may occur in the future are forward-looking statements. Our forward-looking statements generally are accompanied by words such as "may", "will", "estimate", "project", "predict", "believe", "expect", "anticipate", "potential", "plan", "goal", or other words that convey the uncertainty of future events or outcomes. Forward-looking statements provided in this press release are based on Mariner's current belief based on currently available information as to the outcome and timing of future events and assumptions that Mariner believes are reasonable. Mariner does not undertake to update its guidance, estimates or other forward-looking statements as conditions change or as additional information becomes available. Estimated reserves are related to hydrocarbon prices. Hydrocarbon prices used in estimating reserves may vary significantly from actual future prices. Therefore, volumes of reserves actually recovered may differ significantly from such estimates. Mariner cautions that its forward-looking statements are subject to all of the risks and uncertainties normally incident to the exploration for and development, production and sale of oil and natural gas. These risks include, but are not limited to, price volatility or inflation, environmental risks, drilling and other operating risks, regulatory changes, the uncertainty inherent in estimating future oil and gas production or reserves, and other risks described in Mariner's latest Annual Report on Form 10-K and other documents filed by Mariner with the Securities and Exchange Commission (SEC). Any of these factors could cause Mariner's actual results and plans of Mariner to differ materially from those in the forward-looking statements. Investors are urged to read Mariner's latest Annual Report on Form 10-K and other documents filed by Mariner with the SEC.

"Proved" oil and gas reserves are those that can be estimated with reasonable certainty to be economically and legally producible under existing economic conditions, operating methods and government regulations. "Probable," "possible" and "non-proved" reserves, reserve "potential" or "upside" or other descriptions of volumes of reserves potentially recoverable involve estimates that by their nature are more speculative than estimates of proved reserves and accordingly are subject to substantially greater risk of actually being realized by Mariner. The SEC generally does not permit a company's filings with the SEC to include estimates or estimated values of oil or gas resources other than reserves due to concern that resources other than reserves are too speculative and may be misleading.

This press release does not constitute an offer to sell or a solicitation of an offer to buy any securities of Mariner.