Norwegian oil and gas firm Statoil is celebrating a key milestone for its giant Mariner development near Shetland.
Pipe-laying for the £4billion-plus project got under way earlier this week.
About 25 miles of pipelines for gas, oil and diluting agent are being installed on the seabed by the pipe-lay vessel Seven Navica.
Mariner, located about 93 miles east of Shetland, is under development by Statoil – the operator and 65.11% stakeholder – and partners JX Nippon (28.89%) and Dyas (6%).
It is the largest field development in the UK North Sea in more than a decade and expected to be in production for at least 30 years.
Drilling is planned to start in 2016, with production start-up following in 2017. The main platform will have one drilling rig and one well intervention and completion unit.
The development is expected to contribute more than 250million barrels of reserves, with average peak production of around 55,000 barrels a day.
Jon Aksel Brynildsen, project manager for subsea, umbilicals, risers and flowlines, said subsea installation work this year involved more than 200 “vessel days” on nine different ships.
This is in addition to guard vessels, of which the first left Peterhead last Wednesday.
Statoil will have a total of six ships in rotation doing guard vessel duties to support offshore installation activities.
Earlier this year, the seabed was examined along the proposed route of essential pipelines and large rocks blocking it were removed.
When the pipe-laying is complete, other installation vessels will be used for flooding, trenching and rock-dumping.