Texas

In Texas, Marathon's production in the active Mimms Creek Field in East Texas originates from the Bossier and Cotton Valley Sands, which are challenging formations of tight rock more than 2 miles below the surface. Since Marathon remapped these sands and increased drilling activity in 2000, gross risked resources of more than 320 bcf of gas have been identified.

Gross sales from the Marathon-operated Pearwood Field have reached 40 mmcfd since development of the Cotton Valley Carbonate shoal began in early 2005. Additional development drilling is planned through 2009 in the Pearwood Field. Development drilling is also ongoing targeting the Bossier, Cotton Valley, Pettit and Travis Peak formations in other asset areas of East Texas.

Marathon also focuses its exploration activity in East Texas on the Cotton Valley Carbonate and Deep Bossier reservoirs, acquiring more than 25,000 undeveloped net acres in 2007, with plans to drill nine gross (five net) exploration wells in 2008. The Company is also positioned with more than 25,000 net legacy acres in the core of the emerging Haynesville Shale resource play, with initial plans for development in 2009.