- Installed in 1973
- On stream May 1977
- Ceased production in 1998
- Removal completed in 2012
- Also known as Ekofisk Delta
West Ekofisk was discovered by 2/4-5 X, the only exploration well drilled in this structure. Testing yielded commercial volumes of gas and condensate (a very light oil which condenses from the gas) in two zones.
This field is a small circular formation created by a salt structure which had thrust up the reservoir rocks. It lies about 4.5 kilometres west of the main Ekofisk field.
West Ekofisk 2/4 D was a combined production, drilling and accommodation platform located in block 2/4 on the Norwegian continental shelf, eight kilometres west of the Ekofisk Complex.
Its steel jacket (support structure), module support frame (MSF) and drilling modules were built by UIE at St Wandrille in France, while the generator and mud modules came from Offshore Industry Services (OIS) in Kristiansand.
A new accommodation module with 96 beds in double cabins was delivered in 1983 by Leirvik Sveis at Stord south of Bergen. This six-storey structure had the galley, dining room, offices and various leisure facilities on its two lowest stories.
It functioned primarily as a wellhead platform with 15 producing wells, but also carried a test separator measuring 6.1 by 1.2 metres and metering equipment for oil, gas and water. Electricity was provided by a 480V, 1 260kW generator driven by a Kongsberg Viking gas turbine.
The platform was tied back to Ekofisk 2/4 R by a 24-inch pipeline which carried oil and gas simultaneously (two-phase flow).
From 1994, West Ekofisk 2/4 D was remotely operated from the control room on Ekofisk 2/4 T (the tank). The drilling rig and associated equipment were removed in 1997, and it ceased operation the following year.
Until West Ekofisk 2/4 D was shut down in July 1998, the field had produced:
76 million barrels or 12.15342 million standard cubic metres (scm) of oil
25.97430 billion scm of gas
1.429530 million tonnes of natural gas liquids (NGL)
Processing equipment was cleaned and the wells plugged and secured. The platform was removed in 2012.