Frigg Gas Field
Operations were regulated according to an agreement between the UK and Norwegian governments called the Frigg Treaty.
Infrastructural changes were made in three phases:
- Phase I - 1977
- Phase II - 1978
- Phase III - 1981
Geology
The field was discovered at a depth of 1,850 metres (6,070 ft) by the Petronord group (Elf Aquitaine, Total Oil Marine Norsk, and Norsk Hydro) and the Norwegian State in 1971 with Well 25/1-1 using the Semi-submersible Neptune P 81 in 100 metres (330 ft) of water. The well was located following interpretation of a 15 by 20 km grid of Reflection seismology lines recorded in 1965. A 5 by 5 km finer grid of seismic lines were recorded in 1969, followed by a 1 by 1 km grid in 1973, combined with four appraisal wells determined the field was 115 square kilometres (44 sq mi) in area with a 170-metre (560 ft) gas column in Lower Eocene sandstones forming an abyssal fan in the Viking Structural basin. The fan structure appears on seismic sections as a low relief Anticline that includes a Flat spot caused by the Density contrast of the gas.
Development
The Frigg field has been developed through a number of offshore platforms.
Platform | Coordinates | Function | Type | Legs | Well slots | Installed | Production start | Production to |
---|---|---|---|---|---|---|---|---|
Frigg DP1 | 59°52’40”N 02°04’48”E | Drilling platform | Steel jacket | 8 | ? | October 1974 buoyancy tanks collapsed damaged beyond recovery | – | – |
Frigg CDP1 | 59°52’31”N 02°03’42”E | Drilling, production | Concrete gravity | 1 | 24 | September 1975 | September 1977 | TP1 |
Frigg TP1 | 59°52’47”N 02°03’51”E | Treatment | Concrete gravity | 2 | – | June 1976 | September 1977 | MCP01 |
Frigg QP | 59°52’42”N 02°03’54”E | Quarters platform | Steel jacket | 4 | – | July 1975 | – | – |
Frigg DP2 | 59°53’10”N 02°04’21”E | Drilling, production | Steel jacket | 8 | 24 | May 1976 | August 1978 | TCP2 |
Frigg TCP2 | 59°52’48”N 02°04’01”E | Treatment, compression | Concrete gravity | 3 | – | June 1977 | August 1978 | MCP01, DP2 |
Frigg MCP-01 | 58°49’39”N 00°17’12”E | Manifold, compression | Concrete gravity | 1 | – | June 1976 | September 1977 | St Fergus |
Frigg flare platform FP | 59°52’54”N 02°03’21”E | Flare | Articulated steel | 1 | – | October 1975 | December 1977 | From TP1 |
Frigg NE | 59°59’07”N 02°14’52”E | Field control station | Steel tower, concrete base | 6 subsea trees | June 1981 | December 1983 | TCP2 |
The initial production of gas (in 1000 standard cubic metres) was:
Graphs are unavailable due to technical issues. There is more info on Phabricator and on MediaWiki.org. |
Pipelines
Pipelines associated with the Frigg field are as follows:
Start | Terminal | Length | Diameter | Type |
---|---|---|---|---|
TP1 / TCP2 | MCP-01 | 2 × 186 km | 32” | Gas |
MCP-01 | St Fergus | 2 × 174 km | 32” | Gas |
CDP1 | TP1 | 2 × 500 m | 26” | Gas |
CDP1 | TP1 | 500 m | 4” | Condensate |
TP1 | CDP1 | 500 m | 8” | Kill |
DP2 | TCP2 | 2 × 700 m | 26” | Gas |
DP2 | TCP2 | 700 m | 4” | Condensate |
TCP2 | DP2 | 700 m | 8” | Kill |
TP1 | FP | 500 m | 24” | Gas |
TP1 | FP | 500 m | – | Gas air pilot |
Subsea template | TCP2 | 18 km | 16” | Gas |
TCP2 | NEF | 18 km | 1.25” | Methanol |
FCS | Template | 500 feet | 2” | Kill |
Pipelines connected to the Frigg field
- Frigg UK System - natural gas transportation system from the Alwyn North Field in the North Sea via the Frigg field to St. Fergus near Peterhead in Scotland. The Frigg UK System is operated by Total E&P UK Plc.
- Vesterled - mostly the former Frigg Norwegian Pipeline.
- Gas production from the Odin gas field was transported to Frigg TCP2 by a 26 km 20-inch pipeline.
Images
-
Bridge from the Frigg field outside the Norwegian Petroleum Museum in Stavanger
Future plans
The Frigg field may be revitalised. A production licence on the Norwegian side of Frigg was allocated to Equinor in 2016. An appraisal well was drilled on Frigg in 2019. Equinor also holds the licence rights on the UK side of the field.
References
- ^ Heritier et al, 1980, p. 59
- ^ Heritier et al, 1980, p. 60
- ^ Heritier et al, 1980, p. 65
- ^ Oilfield Publications Limited (1985). The North Sea Platform Guide. Ledbury: Oilfield Publications Limited. pp. 223–46.
- ^ Gjerde, Kristin Øye. "New life for Frigg gas field?". INDUSTRIMINNE.NO. Norwegian Petroleum Museum.
Bibliography
- Heritier, F E; Lossel, P; Wathne, E (1980). "Frigg Field-Large Submarine-Fan Trap in Lower Eocene Rocks of the Viking Graben, North Sea". In Halbouty, Michel Thomas (ed.). Giant Oil and Gas Fields of the Decade:1968–1978. AAPG Memoir 30. Tulsa: American Association of Petroleum Geologists. ISBN 0891813063. OCLC 7355859.
External links
- Frigg Industrial Heritage Archived 2009-09-05 at the Wayback Machine - a website by the Norwegian Petroleum Museum, English version
- Frigg decommissioning - at the website of Total E&P Norge
- Frigg UK: 30 Years on
- Frigg in Interactive Energy Map