Mariner Energy Completes Merger

Houston, TX -- Mariner Energy, Inc., an oil and gas exploration and production company, today announced the completion of the merger of its parent, Mariner Energy LLC, with an affiliate of the private equity funds Acon Investments LLC and Carlyle/Riverstone Global Energy and Power Fund II, bringing an end to the company's ownership by Joint Energy Development Investments Limited Partnership, an affiliate of Enron Corp. The transaction was valued at $271.1 million and provided for the repayment of Mariner's existing debt. Carlyle/Riverstone affiliates own 67.0% of the equity interests of Mariner's parent, and Acon affiliates own the remaining 33.0%. Debt financing for the transaction was provided by a group of banks led by The Union Bank of California and BNP Paribas. The transaction was approved by the United States Bankruptcy Court.

Mariner is headquartered in Houston, Texas, and has operations in West Texas and the Gulf of Mexico. At year-end, Mariner had approximately 200 Bcfe of proven reserves, of which approximately 40 percent are located in West Texas, with the remainder located in the Gulf of Mexico. Current daily production is approximately 77 million cubic feet of natural gas and 7,100 barrels of crude oil.

Mariner's current management will continue to operate the company, headed by Scott Josey, Chief Executive Officer.

"Today starts a new and exciting chapter in Mariner's life. We have great confidence in Scott Josey and his management team and believe the company is poised for significant growth and the strengthening of its position as a high-quality independent producer," said David M. Leuschen, Managing Director of Carlyle/Riverstone.

"We were attracted to Mariner because it combines the stable cash flows generated by the onshore West Texas reserves with the growth potential from its exploration activities in the Gulf," said Jonathan Ginns, Managing Director of Acon Investments. Mariner will continue to partner with other E&P companies to explore onshore, on the shelf and opportunistically in the deepwater of the Gulf of Mexico.

"We are excited about the endorsement that we have received from two strong equity sponsors and our bank group. We look forward to creating value for our new shareholders. The future of this company is very bright as a result of this transaction," said Scott Josey.

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