BHP Successful with Neptune-7 Appraisal Well

BHP Billiton has revealed the results from its Neptune-7 appraisal well in the Gulf of Mexico, which was drilled in Atwater Valley Block 618, approximately 135 miles from the Louisiana coast. The well was drilled to a total depth exceeding 18,700 feet in water depths of nearly 6,260 feet and encountered a hydrocarbon column with approximately 114 feet of net oil pay.

Neptune-7 was spud using the GlobalSanteFe's drillship, Glomar Explorer. Information collected from the well will be used to help determine the size of the resource and options for its development. Pre-feasibility studies into the development of the Neptune resources are progressing and expected to be complete by the end of 2004.

Results from Neptune-7 further confirm the resource potential found in previous data collection efforts on the field. This includes Neptune-5, which was drilled in 2003 on Atwater Valley Block 574 and encountered approximately 500 feet of net oil pay, and Neptune-3, which was drilled in 2002 on Atwater Valley Block 617 and logged 130 feet of net pay.

The Neptune prospect is located in the Atwater Foldbelt region of the Central Gulf of Mexico. This area includes the Mad Dog and Atlantis fields, which are currently in development, and the BHP Billiton-operated Shenzi discovery, where appraisal activities are currently underway.

BHP Billiton is the designated operator on the block with a 35-percent working interest. Partners are Marathon Oil Company, which holds a 30 percent working interest; Woodside Energy (USA) Inc., a 20 percent working interest holder; and Maxus (US) Exploration Company, a subsidiary of Repsol YPF, with a 15 percent interest.