Gullfaks
The main Gullfaks field lies in block 34/10 in the northern part of the Norwegian North Sea. It has been developed with three large concrete production platforms.
The Gullfaks A platform began production on 22 December 1986, with Gullfaks B following on 29 February 1988 and the C platform on 4 November 1989.
Produced oil is loaded directly into shuttle tankers on the field, while associated gas is piped to the Kårstø gas treatment plant north of Stavanger and then on to continental Europe.
The A platform is also used for storing and exporting stabilised crude from the Vigdis and Visund fields.
Oil and gas from Gullfaks B is transferred to the A and C platforms for processing, storage and export.
Since June 1994, Gullfaks C has received and processed oil from the Tordis field.
The field set a production record of 605,965 barrels for a single day on 7 October 1994.
The satellite fields – Gullfaks South, Rimfaks, Skinfaks and Gullveig – have been developed with subsea wells remotely controlled from the Gullfaks A and C platforms.
The recovery factor on Gullfaks is 59 per cent, but the goal is to increase into 62 per cent.
Measures to improve recovery include horizontal and extended-reach wells, new completion and sand control technology, and water alternating gas (WAG) injection.
Block 34/10 was awarded in 1978 to three Norwegian companies:
- Statoil, now Equinor (operator)
- Norsk Hydro
- the former Saga Petroleum
This was the first time a purely domestic consortium had been awarded an offshore licence.
Interest in this acreage was very high, and it had been nicknamed the Golden Block before being awarded.
Location: 34/10 in the northern part of the North Sea
Production start: Gullfaks A December 1986, Gullfaks B February 1988, Gullfaks C November 1989
Production: Oil and gas
Gullfaks Sør
Gullfaks Sør lies in blocks 34/10 and 33/12 in the northern North Sea, where water depths are 130-220 metres.
These blocks were awarded in 1978/1995 and 1973 (carve-out 1998) respectively.
Gullfaks Sør is a satellite to the main Gullfaks field, developed with subsea production installations.
The first development phase was approved in March 1996, and came on stream in October 1998. Phase II was approved in June 1998, coming on stream in October 2001.
Phase I covers the production of oil and condensate, with reinjection of associated gas. The eight subsea installations in this part of the development are tied back to the Gullfaks A platform for processing, storage and loading.
Phase II covers production and export of gas and associated liquids, with subsea installations tied back to both Gullfaks A and Gullfaks C.
The gas is piped from Gullfaks to the Statpipe trunkline and on to Kårstø north of Stavanger.
Oil and condensate (light oil) are stabilised and stored on the A and C platforms before being exported by ship.
Gullfaks Sør also includes the separate Rimfaks and Gullveig structures.
Location: 34/10 and 33/12 in the northern North Sea.
Production start: 10 October 1998
Gimle
Gimle lies in the Tampen area of the North Sea, between the Gullfaks and Visund fields. The Gimle well is tied back to the Gullfaks C platform.
Reserves were proven at Gimle in December 2004 and the field commenced test recovery shortly after. The find, previously known as Topas, was proven through a 7,400-metre well drilled from the Gullfaks C platform.
The Gimle find covers two licences. The owners established a Gimle Unit which covers the Gimle area, with Equinor as operator.
Since the Gimle Unit does not have the same ownership structure as Gullfaks, it has been necessary to establish a tie-back and processing contract relating to the Gullfaks licences.
Production start: 19.05.2006
Production: Oil
Gullveig
Gullveig is a satellite to the main Gullfaks field in block 34/10.
It has been developed with a subsea template installed 11 kilometres west of Gullfaks.
This installation is tied back via a flowline to the Gullfaks A platform.
Gullveig began production on 10 October 1998.
Skinfaks
Skinfaks is a satellite to the main Gullfaks field in block 34/10. The field was proven in 2002 and comprises several smaller structures.
The field was developed with a subsea production system tied in to existing xmas trees on the Gullfaks South satellite field.
Production from Skinfaks started on 27 January 2007.
Rimfaks
Rimfaks is a satellite to the main Gullfaks field in block 34/10. It has been developed with three subsea templates tied back to the Gullfaks A platform.
Rimfaks has been in production since 7 February 1999.