- Increases working interest to 53.8%

- Estimated proved reserves acquired for less than $1.85 per Mcf

HOUSTON, Jan. 5 /PRNewswire-FirstCall/ -- Mariner Energy, Inc. (NYSE: ME) today announced that it has purchased an additional 11.6% working interest in the Bass Lite natural gas field (Atwater Valley Block 426) from Energy Resource Technology (ERT) for approximately $32.6 million. The purchase price is subject to customary post-closing adjustments. The acquisition provides internally estimated proved reserves of more than 17.6 billion cubic feet equivalent to Mariner.

Mariner Energy exercised its preferential right to acquire the interest following ERT's negotiated sale of its Bass Lite asset to a third party. The transaction was completed December 19, 2008 with an effective date of November 1, 2008.

Bass Lite is located in water depths of approximately 6,750 feet. Production from Bass Lite commenced in February 2008 from an early production system until the primary two-well development system was completed in August. Gross production from the development currently averages approximately 110 million cubic feet of natural gas per day. Natural gas is produced from Bass Lite via a 56-mile subsea tieback to the Devils Tower Spar located on Mississippi Canyon Block 773.

Mariner is the operator at Bass Lite and with this transaction owns a 53.8% working interest in the development. Other working interest owners in the field include Deep Gulf Energy LP, ENI, and EOG Resources, Inc.

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 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 additional information becomes available. 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, capital availability, 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 the Annual Report on Form 10-K for the fiscal year ended December 31, 2007, 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 to differ materially from those in the forward-looking statements. Investors are urged to read the Annual Report on Form 10-K for the year ended December 31, 2007 and other documents filed by Mariner with the SEC.

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

SOURCE Mariner Energy, Inc.