The first of 49 foundation piles were driven into the seabed late last week in 250m of water.

Each pile is about 66m long and weighs more than 450 tonnes.

Ichthys managing director Louis Bon said that installation of the complex network of subsea infrastructure and equipment across the 800 square kilometre Ichthys field was progressing well.

"The mooring installation works are part of the offshore installation campaign that the Ichthys LNG Project commenced in October 2014," Bon said.

"As part of that campaign, we are installing more than 30,000t of subsea infrastructure and equipment across the Ichthys field so that we will be able to safely and efficiently extract gas and condensate."

"The mooring work is being carried out specifically to prepare for the arrival of the project's two big offshore facilities - the central processing facility and the floating production, storage and offloading facility."

The CPF and FPSO are under construction in South Korea and are expected to be delivered to the field in 2016 where they will be moored for the projected 40 year lifespan of the field by 40,000t of chain secured to about 20,000t of foundation piles.

The mooring installation work scope is being led by Heerema Marine Contractors using the deepwater construction vessel DCV Aegir, under subcontract to McDermott Australia.

Moorings will be installed by DCV Aegir in non-continuous phases, with piles driven first and mooring chains laid out later in the campaign.

As of May 2015, the Ichthys project had installed 47km of flowlines, more than 30 flowline sleeper structures and a 6500t riser support structure in the Ichthys field as part of the offshore installation campaign.