Announces Deepwater Gulf of Mexico Discovery;
Expands 2009 and 2010 Commodity Derivative Positions

Anadarko Petroleum Corporation (NYSE:APC) today provided updates on its exploration and hedging activities. Most significantly, Anadarko announced a Miocene discovery at the Samurai prospect in the deepwater Gulf of Mexico in Green Canyon block 432. The discovery well, located approximately 12 miles north of the Marco Polo platform, encountered more than 120 feet of net oil pay in several high-quality sands.

“Samurai marks our third discovery in the deepwater Gulf of Mexico this year,” said Bob Daniels, Anadarko Sr. Vice President, Worldwide Exploration. “We are very pleased with the results of this initial well, which is located in close proximity to existing infrastructure, demonstrating the value of our hub-and-spoke approach. We look forward to drilling a sidetrack appraisal well within the next year. The continued success of our worldwide exploration program reinforces our expectations of discovering approximately 350 million BOE (barrels of oil equivalent) of net resources in 2009, which is a 50-percent increase from the expectations we communicated at our investor conference in March of this year.”

Samurai was drilled using the Belford Dolphin drillship. The well is located in approximately 3,400 feet of water and was drilled to a depth of about 31,700 feet. Anadarko operates the block with a 33.33-percent working interest. Partners in the discovery include Murphy Oil Corporation (NYSE:MUR) and Samson Offshore Co., each with a 33.3-percent working interest.

Anadarko is mobilizing the Belford Dolphin to West Africa to commence drilling on the company’s Venus prospect in Block SL-6/07 (50-percent working interest) offshore Sierra Leone followed by its South Grand Lahou prospect in Block 105 (55.88-percent working interest) offshore Côte d’Ivoire. Both prospects have seismic signatures and characteristics similar to the world-class Jubilee field offshore Ghana. Following these drilling activities, Anadarko plans to move the drillship to begin the company’s multi-well, deepwater drilling program offshore Mozambique.

Anadarko also is currently drilling the Vito prospect in the Gulf of Mexico, a Miocene test located in Mississippi Canyon block 984 and expects to have results in the coming weeks. Anadarko operates the Vito exploration well with a 20-percent working interest. The company’s activities at the Turtle Lake Lower-Tertiary prospect (20-percent working interest) in the Gulf of Mexico and the Gouda pre-salt prospect (30-percent working interest) offshore Brazil were unsuccessful.

In addition to the exploration activities described above, Anadarko announced that it has expanded its commodity derivative program. The company entered into additional fixed-price natural gas swaps for June, July and August 2009 and also increased its 2010 derivative positions for both crude oil and natural gas through costless, three-way collars.

Additional details surrounding the company’s commodity derivatives are provided in the tables attached to this news release.

A map of the Samurai discovery and other Anadarko-operated discoveries, producing fields and infrastructure in the Green Canyon area of the Gulf of Mexico will be available under the “Media Center/Anadarko News” tabs on the company’s Web site at www.anadarko.com.

Anadarko Petroleum Corporation’s mission is to deliver a competitive and sustainable rate of return to shareholders by exploring for, acquiring and developing oil and natural gas resources vital to the world’s health and welfare. As of year-end 2008, the company had approximately 2.3 billion barrels of oil equivalent of proved reserves, making it one of the world’s largest independent exploration and production companies. For more information about Anadarko, please visit www.anadarko.com.

This news release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Anadarko believes that its expectations are based on reasonable assumptions. No assurance, however, can be given that such expectations will prove to have been correct. A number of factors could cause actual results to differ materially from the projections, anticipated results or other expectations expressed in this news release, including our ability to successfully drill, complete, test and produce the wells described in this release. See “Risk Factors” in the company’s 2008 Annual Report on Form 10-K and other public filings and press releases. Anadarko undertakes no obligation to publicly update or revise any forward-looking statements.

Cautionary Note to U.S. Investors: The United States Securities and Exchange Commission (“SEC”) permits oil and gas companies, in their filings with the SEC, to disclose only proved reserves that a company has demonstrated by actual production or conclusive formation tests to be economically and legally producible under existing economic and operating conditions. Anadarko uses certain terms in this news release, such as “net resources” and similar terms that the SEC’s guidelines strictly prohibit Anadarko from including in filings with the SEC. U.S. Investors are urged to consider closely the disclosure in Anadarko’s Form 10-K for the year ended Dec. 31, 2008, File No. 001-08968, available from Anadarko at www.anadarko.com or by writing Anadarko at: Anadarko Petroleum Corporation, 1201 Lake Robbins Drive, The Woodlands, Texas 77380, Attn: Investor Relations. You can also obtain this form from the SEC by calling 1-800-SEC-0330.

Anadarko
Media:
John Christiansen, 832-636-8736
john.christiansen@anadarko.com
Matt Carmichael, 832-636-2845
matt.carmichael@anadarko.com
Investors:
John Colglazier, 832-636-2306
john.colglazier@anadarko.com,
Chris Campbell, CFA, 832-636-8434
chris.campbell@anadarko.com