BHP Billiton's Neptune-5 appraisal well in the Gulf of Mexico indicates 'impressive' sands

By OGJ editors

HOUSTON, Aug. 8 -- BHP Billiton reported Friday the results from its Neptune-5 appraisal well, which was spudded July 2 on Atwater Valley Block 574 in the Gulf of Mexico about 135 miles off Louisiana. The well found a gross hydrocarbon column of nearly 1,200 ft, BHP said, with more than 500 ft (total vertical thickness) of net oil pay.

Neptune prospect is in the Atwater Foldbelt region of the Central Gulf of Mexico, and area that includes Mad Dog and Atlantis fields, which are currently in development, and the BHP Billiton-operated Shenzi discovery, where an appraisal well will be drilled later this year.

"The net column is significantly larger than those recorded in the similar Miocene reservoir sandstone intervals of previous Neptune wells," BHP said, "and the preliminary evaluation of the fluids indicates the presence of oil similar in quality to the medium sour crude found at the Atlantis and Mad Dog fields."

Neptune-5 was drilled to 19,142 ft TD in 6,215 ft of water using BHP Billiton's CR Luigs drillship.

"The well logs at Neptune-5 indicate thick sands and are amongst the most impressive we've seen in the Gulf of Mexico," said Philip Aiken, BHP Billiton Petroleum president and CEO.

Following its positive results from its Neptune-3 well in July 2002, BHP and its partners have "accelerated the appraisal program at the field over the last year, drilling 3 wells since mid-2002," Aiken said.

Currently, the partners have taken core and fluid samples from Neptune-5, which will be sidetracked while the partners assess options for other associated operations at the well, BHP said.

BHP Billiton is the operator on the block with a 35% working interest. Partners are Marathon Oil Co. 30%, Woodside Petroleum Ltd. 20%, and Repsol-YPF SA unit Maxus (US) Exploration Co. 15%.