Anadarko Announces Deepwater Gulf of Mexico Discovery

Anadarko Petroleum Corporation announced a substantial oil discovery at its Heidelberg prospect in Green Canyon block 859 in the deepwater Gulf of Mexico. The discovery well encountered more than 200 feet of net oil pay in several high-quality Miocene sands.

“The Heidelberg discovery further validates our geologic understanding of the subsalt Miocene trend. The well encountered the same-age sands and reservoir characteristics similar to the previously announced Caesar/Tonga discoveries,” said Bob Daniels, Anadarko Sr. Vice President, Worldwide Exploration. “Since 2005, we have drilled seven successful exploration wells in this Middle-Miocene trend, each targeting resources of more than 100 million barrels.”

Heidelberg is located in approximately 5,000 feet of water and, to date, has been drilled to a total depth of approximately 28,500 feet. Heidelberg’s proximity to Anadarko’s 100-percent owned Constitution spar enhances the company’s flexibility to consider a variety of development options after further appraisal, which Anadarko intends to conduct in the second half of 2009. Anadarko operates the block with a 44.25-percent working interest. Partners in the discovery include Mariner Energy, Inc. (12.5-percent working interest), ENI (12.5-percent working interest), StatoilHydro (12-percent working interest), ExxonMobil (9.375-percent working interest) and Cobalt International Energy, L.P. (9.375-percent working interest).

Once drilling operations are complete at Heidelberg, Anadarko plans to drill the Vito prospect in Mississippi Canyon block 984, which Anadarko operates with a 20-percent working interest. Vito is a 30,500-foot test, targeting Miocene objectives in 4,000 feet of water and is on trend with other recently announced industry discoveries at Kodiak and Freedom.

Anadarko also is currently drilling the Shenandoah Lower-Tertiary prospect, located in Walker Ridge block 52. Anadarko operates Shenandoah with a 30-percent working interest.

An additional exploration well is planned to spud during the first quarter at the Samurai prospect, which is operated by Anadarko with a 33.33-percent working interest. Samurai is a Middle- and Lower-Miocene test located in Green Canyon block 432.