Atwood Osprey's Easter adventure during Cyclone Olwyn last month saw it break its moorings and float away from the Iago-B drilling location, drifting almost 6km.

"The first thing we knew when we were looking at the area was that there was a drill rig sitting above one of our main flowlines for Pluto," Woodside managing director Peter Coleman said yesterday.

"We chose to shut in the pipeline, which would have been a normal thing that we would have done if were operating our business and if it was a planned activity … and then we assisted our vessels to survey the pipeline, and subsequently move the rig to a safer place."

The rig was operated by Chevron in an adjacent block, drilling for the Wheatstone LNG development, a project that Woodside is now involved in via its Julimar-Brunello gas fields, although Woodside has no interest in the Iago field.

"We are still assessing liabilities. Fortunately there was no to very minimal damage to Pluto, to the pipeline," Coleman said.

"We are assessing that right now, to the extent of any claims that may be made, but I will not go too far into that because it is still under legal privilege."

Coleman said it would be a few weeks before Woodside made any decisions on asking the Iago participants to pay up, or if it would lodge an insurance claim, but Woodside was free of any blame for the lost production.

He also revealed that there was a minor impact on the Wheatstone pipeline with the cyclone damaging the pipeline's coating.