Shell's ambitions for establishing its first ever floating LNG facility in Australia have been boosted by a significant new gas discovery near its Prelude field in the Browse Basin.

Concerto was discovered with the tenth well of a 12 well program at Shell's wholly-owned WA-371-P permit, 450km north west of Broome in the Kimberley, where it has already confirmed more than 2 trillion cubic feet of gas at Prelude.

Although still early days, Concerto lies only 16km from the Prelude field, significantly enhancing its development prospects.

"It is too early to estimate volumes but the indications are sufficient for us to be looking at ways to commercialise it," a Shell spokeswoman told WA Business News. "Work is now underway to establish the extent of the find and consider development options."

Although too small to support a standalone onshore LNG facility, Prelude is a frontrunner to become the first of several Shell gasfields developed using innovative floating LNG (FLNG) technology. Shell last month awarded Samsung Heavy Industries and Technip a contract to design, construct and install multiple FLNG plants over a 15 year period. Shell is expected to nominate the first proposed project by the end of the year.

Speaking after addressing a CEDA function in Perth earlier this week, Shell Australia chairman Russell Caplan confirmed that Prelude was one of the frontrunners to become Shell's first FLNG development.

And though FLNG was largely aimed at relatively small fields, Mr Caplan said it was also possible that multiple FLNG facilities could be used to commercialise more significant gas resources in areas where economic, social or environmental factors made onshore development less attractive or unviable.

Shell envisages each FLNG project, entailing ship-mounted gas processing and liquefaction facilities, would have the capacity to produce around 3.5 million tonnes of LNG annually. The vessel would be similar to Floating Production, Storage and Offloading (FPSO) facilities commonly used to develop offshore oil fields, with the LNG able to be transferred to a more conventional LNG tanker moored alongside for export to customers.