Mariner Strengthens Position in GOM, Bids on 45 Blocks

Mariner Energy announced that the company is the apparent high bidder on 45 blocks on which it bid at the U.S. Minerals Management Service Central Gulf of Mexico Lease Sale 213. The company's working interests on the blocks ranges from 16.67-100%, with a net exposure of approximately $62.8 million. Mariner expects the leases to be awarded over the next several months subject to MMS review and approval.

Mariner's apparent high bids include nine shelf blocks and 36 deepwater blocks covering 27 prospects. These include three conventional shelf, four deep shelf, one deepwater Wilcox, one deepwater conventional amplitude, and 18 deepwater subsalt Miocene prospects. In the Keathley Canyon and Walker Ridge Lease Protraction Areas, Mariner submitted joint bids with Anadarko Petroleum Company and Plains Exploration & Production Company, its co-venturers at the Lucius discovery on Keathley Canyon Block 875. Mariner partnered with both companies on 23 blocks and with Anadarko on six additional deepwater blocks. The apparent high bids include several drill-ready prospects and mature leads.

Mariner also announced that the reservoir engineering firm DeGolyer and MacNaughton recently evaluated 26 deepwater Gulf of Mexico prospects identified by Mariner as top high potential prospects in its current deepwater exploration portfolio (excluding any Lease Sale 213 prospects). D&M estimates that the 26 prospects hold prospective resource potential of approximately 1.28 billion barrels of oil equivalent, net, unrisked to Mariner, providing independent, third-party verification of the potential of a portion of Mariner's deepwater exploration portfolio.

"We are very pleased with the results of the lease sale as we strengthened our positions in existing holdings -- including two blocks offsetting our Lucius discovery -- expanded our positions in the prolific subsalt play in prospects similar to those evaluated in D&M's encouraging report, as well as broadened our portfolio in other exploration play fairways. We look forward to working with our partners on these projects," said Mike van den Bold, Senior Vice President and Chief Exploration Officer.