Operator Woodside Petroleum (16.67%) has announced the development of the Keast, Dockrell, Sculptor, Rankin, Lady Nora and Pemberton fields in the Greater Rankin Trend in order to unlock a further 1.6 trillion cubic feet of gas, sufficient resources to feed one of the North West Shelf Venture's five LNG trains for a decade.

The fields will be hooked up to the existing Goodwyn-A platform via new subsea infrastructure and a modest 35km-long, 16-inch pipeline.

Gas delivery will initially commence from five wells in the Lady Nora, Pemberton, Sculptor and Rankin fields from 2019, with the remaining three wells in the Keast and Dockrell fields expected in the first half of 2020.

The project sits in less than 130m of water and should take around eight months to bring into production.

The project is the fourth major gas development for the NWS project in the past seven years following GWF-1, the North Rankin redevelopment and Persephone.

Woodside CEO Peter Coleman described GWF-2 as an "economically robust" project that will deliver significant value by leveraging Woodside's substantial experience in delivering major subsea tieback projects.

"The GWF-2 project continues a series of NWS project subsea tiebacks that are commercialising its gas reserves in a timely and efficient manner to extend plateau production," Coleman said.

Woodside operates the NWSV for BHP Billiton, BP, Chevron Corporation, Japan Australia LNG and Shell.

All partners in the 30-year-old project own a 16.7% share.

The expansion of the development represents the next phase in gas supply to the existing North West Shelf Venture's Goodwyn-A platform, a key part of what remains Australia's largest LNG project.

The broader Greater Western Flank area consists of 16 fields located to the south-west of Goodwyn-A.

The NWSV is Australia's largest LNG project, with capacity for 16.5 million tonnes per annum.