BHP Completes Drilling Campaign Off Western Australia

BHP Billiton has successfully completed its four well drilling program in its operated license block WA-255-P(2) in the Exmouth Sub-basin in waters 65 kilometers from Exmouth in northwest Western Australia.

The purpose of the drilling campaign was to appraise the discovery at Stybarrow (February 2003) and the oil shows at Eskdale (March 2003), and to test the further exploration potential of the block.

Two appraisal wells, Stybarrow-3 and Stybarrow-4 and two exploration wells, Eskdale-2 and Knott-1, were drilled in the permit from 18th April to 10th July using the semisubmersible drilling rig the Atwood Eagle.

BHP Billiton Petroleum President Americas/Australia Operations and Technology Mike Weill said the results from the Stybarrow appraisal wells were encouraging and provided vital information about the size of the Stybarrow oil reserve.

"Our interpretation of the preliminary well data has enhanced our previous perception of the potential volume of the Stybarrow field, indicating Stybarrow is a medium-sized oil accumulation," Mr Weill said.

"This is a positive outcome and Petroleum's Australia Operated Asset Team is continuing with plans to commercialise the prospects.

"At this stage no decision has been made on the nature of any development, but we are assessing a number of options including stand-alone facilities and co-development with other accumulations in the area.

"BHP Billiton believes the Exmouth Sub-basin is developing as an important oil province in Australian waters, having yielded a number of small to medium oil discoveries in recent years.

"We have now drilled a total of nine wells in WA-255-P(2) in 2003 and to date in 2004, and are continuing to assess the potential of adjacent prospects," Mr Weill said.

BHP Billiton is also currently operating on behalf of the WA-271-P joint venture (Woodside, operator 60%, Mitsui 40%) the drilling of the exploration well Indian-1. This well is located in WA-271-P, and is close to the boundary of WA-255-P(2).

Data from the well may assist BHP Billiton to assess further exploration potential, drilling and appraisal requirements in WA-255-P(2).

Recent drilling programme summary:

  • Eskdale-2 commenced drilling on 18th April encountered a gross oil column of 13 meters and a gross gas column 24 meters. Water depth was 830 meters.
  • Stybarrow-3 drilled on 18th May encountered a gross oil column of 6.5 meters and the subsequent sidetrack well Stybarrow-4, drilled on 4th June, intersected a 16 meter gross oil column within the primary target Macedon Member sandstone. Water depth was 792 meters. The well location was approximately 2 kilometers northeast of Stybarrow-1.
  • Knott-1 drilled on 28th June and plugged and abandoned on 10th July. Water depth was 681 meters.

  • Previous drilling in WA-255-P(2) in 2003:

  • The Stybarrow oil discovery was made in February, when the Stybarrow-1 well encountered a gross oil column of 23 meters with 18.6 meters of net pay in the Macedon Member sandstone reservoir. Water depth was 825 meters.
  • Other wells were; Eskdale-1 (March), Skiddaw-1 and Skiddaw-2 (May) and Stybarrow-2 (June).

  • BHP Billiton owns a 50% interest and is the operator of WA-255-P with 50% held by Woodside Energy Limited.

    BHP Billiton is also undertaking a drilling campaign in the nearby block WA-12-R (BHP Billiton, operator 71.43%, Apache Energy 28.57%) around its Ravensworth (WA-155-P(1)) and Crosby (WA-12-R) discoveries. This five well program is due to conclude in August.