Project Profile
Value: US$760 million
Location: 40 miles offshore in the Exmouth Sub-Basin, Australia
Start-up Year: November 2007
Production end: August 2015
Oil reserves: 60 to 90 MMbo
Water depth: 825 m
Located 40 miles (65 kilometres) offshore northwest Australia in the Exmouth Sub-Basin, the Stybarrow field development project is on license Block WA-255-P(2) and production Block WA-32-L. Ranked as Australia\'s deepest oil field development, Stybarrow is in waters measuring 2,707 feet (825 metres) on the Southern Carnarvon Basin. Incorporating the Stybarrow and the Eskdale fields, this project boasts a combined reserve estimate of 60 to 90 MMbo. Stybarrow is operated by BHP Billiton, which holds a 50% interest. Woodside Energy serves as the joint venture partner on the block with the remaining 50% interest.
Drilling
The permit on the block was awarded in 1994; and in 2003 and 2004, an extensive drilling campaign was performed on the field. In February 2003, the Stybarrow-1 exploration well discovered a 75-foot (23-metre) oil column in the Macedon member sandstone reservoir. Drilled in March 2003, the Eskdale-1 soon followed with promising oil shows. Both wells were drilled by the Atwood Falcon semisub. Appraisal drilling was then conducted on the fields, resulting in a number of confirmations. In April 2004, the Eskdale-2 appraisal well found a 43-foot (13-metre) oil column, as well as a 79-foot (24-metre) gas column. In May 2004, the Stybarrow-3 intersected an oil column measuring 21 feet (6.5 metres); and in June 2004, the Stybarrow-4 sidetrack well encountered a 52-foot (16-metre) oil column. In 2006, the Atwood Eagle semisubmersible undertook development drilling on the two fields.
Field Development
At a total cost of US$760 million, the field development concept for Stybarrow includes a subsea development, incorporating both Stybarrow and the nearby oil rim of Eskdale, tied to an FPSO. The subsea development includes 6 production wells, 2 gas-lift wells, 1 gas-injection well, and 2 water-injection wells. In December 2005, Vetco Gray was awarded the contract to supply the subsea production systems for the project, including horizontal xmas trees, multiplexed electro-hydraulic production controls and distribution equipment, remote connection systems and installation tooling and services. For a consideration of US$160 million, a joint venture between Technip and Subsea 7 was awarded the contract to design, fabricate, install and pre-commission the 30 miles (48 kilometres) of flexible risers, flowlines and jumpers, as well as the 10 miles (16 kilometres) of static umbilicals on Stybarrow. Additionally, the contract included the installation of the FPSO spider buoy and mooring system.
Project partners tapped MODEC in March 2006 to provide the dual-hulled FPSO, newly built by Samsung Heavy Industries. The contract included the engineering, procurement, construction, installation and commissioning of the vessel, named the Stybarrow Venture. In a 10-year contract with five one-year extensions, MODEC owns and operates the FPSO for the project partners. With a storage capacity of 900,000 barrels, the Stybarrow Venture FPSO has a total liquid processing capacity of 100,000 bpd, a crude production capacity of 80,000 bopd, a gas production capacity of 45 MMcf/d (1.3 MMcm/d) and a water injection capacity of 110,000 bwpd.
In April 2006, MODEC subcontracted the topsides processing units to Toyo Engineering, which were manufactured in modules. In a US$62 million contract, MODEC subcontracted the Stybarrow Venture FPSO\'s turret mooring system to FMC Technologies. Allowing the vessel to escape seasonal cyclones, the FPSO is moored in 825 metres of water through a dis-connectable internal turret.
Production
A number of months ahead of schedule, production commenced from the Stybarrow project on November 11, 2007. The first well to come online was that of the Eskdale field, and the project quickly ramped up to full production as other wells were tied-in. Within two months, production on the field had already reached and sustained a daily level of 80,000 bopd. In that time, the project had already produced 2.5 MMbo. The field life estimate on the project is 10 years.
Operators:
BHP Billiton: Operator with 50% interest
Woodside Energy: 50% interest
Contractors:
MODEC: Dual-hulled FPSO and operation of the FPSO
Subsea 7: Design, fabricate, install and pre-commission of flexible risers, flowlines and jumpers and the installation of the FPSO
Technip: Design, fabricate, install and pre-commission of flexible risers, flowlines and jumpers and the installation of the FPSO
Transocean: Drilling semi-submersible Jack Bates
Subcontractors:
FMC Technologies: FPSO\'s turret mooring system
Sal Heavylift: Engineer and execute the sea transportation of 36 subsea cable reels for Subsea 7/Technip
Toyo Engineering: Topsides processing units