2010-01-07-2009-11-05-2009-11-05

Acquired 50% WI in deepwater GOM East Breaks 597 Balboa prospect, gaining 4 MMBOE 2P.

Mariner Energy Inc., Houston, (NYSE: ME) has reported that in third-quarter 2009 it acquired a 50% working interest in the deepwater Gulf of Mexico East Breaks 597, known as Balboa, from an undisclosed seller for an undisclosed price. Estimated gross proved plus probable reserves are 7- to 8 million barrels of oil equivalent. Mariner has assumed operations and expects production to begin fourth-quarter 2010. Additionally, Mariner swapped eight deepwater blocks in the Heidelberg area of the Gulf of Mexico with Anadarko Petroleum Corp., The Woodlands, Texas, (NYSE: APC) and farmed into Anadarko's Keathley Canyon 875 prospect, known as Lucias. The prospect is currently drilling.