Skjold Oil Field
The field
The Skjold oil field is located in Block 5504/16 of the Danish North Sea. The name Skjold translates as 'shield' in English. The field was discovered in March 1977 and is a Danian and Upper Cretaceous chalk anticline with salt tectonics. The reservoir has the following characteristics:
| Skjold reservoir properties | |
|---|---|
| Parameter | Value |
| Field delineation | 33 km |
| Reservoir depth | 1,600 m |
| API gravity | 30° |
| Gas/oil ratio | 510 scf/bbl |
| Sulfur | 0.30% |
| Recoverable reserves | 30-45 million barrels |
Owners and operators
The field was originally licensed to a joint venture called Dansk Undergrunds Consortium (DUC) comprising Shell (40.0%), A.P. Moeller (30.0%), Chevron (15.0%), and Texaco (15.0%). The field was originally operated by Maersk Oil & Gas A/S.
By 2013 ownership of the Skjold field was by Norwegian Energy (37.0%), TotalEnergies (43.0%) and Nordsøfonden (20.0%). The field was operated in 2013 by Maersk Olle og Gas A/S.
As of 2023, it is owned by BlueNord (36.8 %), Nordsøfonden (20.0 %) and TotalEnergies (43.2%). The field is operated by TotalEnergies.
Development
The field was originally developed by a single unattended wellhead platform. No processing was undertaken on the Skjold, and well fluids were routed via an 11km, 6-inch pipeline to the Gorm complex for processing. The Skjold platform was remotely operated from the Gorm installation.
In 1988 a system for the treatment and injection of water into the reservoir was installed on a jack-up rig adjacent to Skjold. This was later replaced by permanent water injection facilities on Gorm with injection water piped to Skjold.
Further infrastructure was subsequently added to the field. This comprised two installations, designated Skjold B and Skjold C, bridge linked to the original installation now designated Skjold A. Skjold B is a wellhead platform allowing further wells to be drilled to reach outlying areas of the reservoir. Skjold C is an accommodation platform. Outline details of the Skjold field platforms are summarised in the table.
| Skjold field infrastructure | |||
|---|---|---|---|
| Platform | Skjold A | Skjold B | Skjold C |
| Coordinates | 55°31’53”N 04°54’34”E | 55°31'52"N 4°54'32"E | 55°31'52"N 4°51'24"E |
| Water depth, metres | 40 | 40 | 40 |
| Fabrication | Jacket: Monberg & Thersen, Aalborg
Topsides: Volund Energiteknik, Essbjerg |
||
| Jacket / substructure weight, tonnes | 1308 | 545 | 830 |
| Topside weight, tonnes | 900 | 1100 | 1200 |
| Function | Wellhead | Wellhead, bridge link to A platform | Accommodation, bridge link to A platform |
| Accommodation | 8 (emergency) | Nil | 16 |
| Type | Steel jacket | STAR (see note) | STAR |
| Legs | 4 | 3 | 3 |
| Piles | 4 | 3 | 3 |
| Well slots | 9 | 7 | Nil |
| Helideck | S61 helicopter | — | Yes |
| Installed | May 1982 | 1994 | 1994 |
| Production start | November 1982 | 1994 | — |
| Oil and gas production to | Gorm D | A platform | — |
Note: STAR (Slim Tripod Adapted for Rig) is a concept developed by Maersk comprising a three-leg base piled to the seabed supporting a single large diameter column above sea level.
In 1994 a second 11 km pipeline from Skjold to Gorm was laid, this was associated with the increased production from the Skjold field.
As of 2023, there are 16 oil-producing wells and seven water injection wells.
Production
Peak oil production was in 1991 at 47.08 thousand barrels of oil per day.
To maintain production the reservoir pressure is kept high by water injection. Injection water is obtained from the Gorm complex. By 2014 there were 19 production wells and nine water injection wells.
Total fluid production to January 2014 was 45.38 million cubic metres of oil, 3.75 billion normal cubic metres of gas, and 70.65 million cubic metres of water. Water injection was 126.04 million cubic metres of water. The estimated reserves were 6.4 million cubic metres of oil, sufficient to sustain economic production until 2038.
The Danish Energy Agency publishes tables and bar charts of oil, gas and water production from the field, from commissioning in 1982 to the present day.
See also
- Gorm Field
- Tyra field
- Dan oil field
- Halfdan field
- Siri, Nini and Cecilie oil fields
- South Arne oil and gas field
- Valdemer oil and gas field
- Harald gas field
- Ravn oil field
References
- ^ Gallimore, David; Madsen, Tony (1985). The North Sea Platform Guide. Ledbury: Oilfield Publications Limited. pp. 613–15. ISBN 9789995350512.
- ^ "Danish to English Dictionary". bab.la. Retrieved 23 September 2023.
- ^ "Oil & gas field profile: Skjold Conventional Oil Field, Denmark". Offshore Technology. 28 July 2023. Retrieved 20 September 2023.
- ^ Nordsoefonden. "Oil and gas producing fields". Retrieved 24 September 2023.
- ^ Oil and gas in Denmark, Exploration and Production 1989 (PDF). Danish Energy Agency. 1989. ISBN 8789072243. Retrieved 24 September 2023.
- ^ Danish Energy Agency (2014). Oil and gas production in Denmark in December 2013 (PDF). Copenhagen: Danish Energy Agency. pp. 88–89. ISBN -978-87-93071-71-1.
- ^ Maersk (March 1994). "Maersk Post 3/1994" (PDF). Maersk. Retrieved 20 September 2023.
- ^ OSPAR (Convention for the Protection of the Marine Environment of the North East Atlantic) (2013). "Offshore Installations Inventory". OSPAR. Retrieved 20 September 2023.
- ^ Maersk Oil DBU (2016). "ESIA Maersk Oil DBU Technical Sections" (PDF). Retrieved 24 September 2023.
- ^ A Barrel Full. "Skjold Oil Field". A Barrel Full. Retrieved 20 September 2023.
- ^ "Statistics data, key figures and energy maps". Danish Energy Agency. 25 August 2016. Retrieved 20 September 2023.
