In February, Mariner produced 63,000 barrels of oil equivalent (boe) per day from the Gulf Shelf and deepwater, the Permian basin and unconventional onshore plays. At year-end 2009, Mariner had estimated proved reserves of 181 million boe (47% liquid hydrocarbons) as well as unbooked resource potential of two billion boe.

Steven Farris, chairman and CEO of Apache, said: “This is a strategic step and a natural extension into the deepwater Gulf for Apache. Mariner provides an exciting new platform for growth in the deepwater and complements our strengths in the Gulf Shelf and the Permian Basin. Based on our experience working with the Mariner team, we also believe the two companies will make an excellent cultural fit.”

Scott Josey, chairman, president and CEO of Mariner, said: “The combination with Apache is an excellent outcome for Mariner’s stakeholders. Our partners will work with a world-class company with the financial and technical resources to fully exploit our assets. Our employees will benefit from the opportunities provided in a large company with values similar to Mariner’s.”

Mariner’s deepwater portfolio includes nearly 100 blocks, seven discoveries in development – including interests in Lucius and Heidelberg – and more than 50 prospects.

Apache has said that it will acquire additional Gulf Shelf assets from Devon Energy that add production of 19,000 boe per day with year-end 2009 estimated proved and probable reserves of 83 million boe across 158 blocks.