The Edda oil and gas field was a crude oil and associated gas production field in the Norwegian sector of the central North Sea. Production of oil and gas started in 1979, peak oil and gas was achieved in 1980. Production ceased in 1998 and the installation and field infrastructure were dismantled in 2012.
The characteristics of the Edda field reservoir are as follows. [1] [2] [3]
| Field | Edda |
| Reservoir | Maastrichtian and lower Paleocene chalk. Upper Cretaceous Tor formation |
| Block | 2/7a |
| Reservoir depth | 3100 m, 10,500 feet |
| API gravity | 33-39° |
| Gas Oil ratio (GOR) | 1,125 scf/bbl (standard cubic feet / barrel) |
| Sulphur content | 0.1% |
| Pressure | 7,175 psi (49,470 kPa) |
| Discovery | September 1972 |
| Recoverable reserves | 44-68 million barrels oil; 220-600 billion cubic feet gas |
The field was owned and operated by ConocoPhillips Skandinavia AS. [2]
The field was developed through a single offshore installation, designated Edda ‘C’. [1] [2] [3]
| Name | Edda ‘C’ |
| Coordinates | 56.464839°N 3.104464°E |
| Water depth | 71m |
| Bridge | To flare structure |
| Installation | May 1978 |
| Function | Production and accommodation |
| Production start | 1979 |
| Type | Steel jacket |
| Substructure weight tonnes | 6,155 |
| Topsides weight tonnes | 10,390 |
| Number of wells | 13 (15 slots) |
| Legs | 12 |
| Piles | 12 |
| Flare | 3-leg jacket |
| Status | Decommissioned |
| Export, liquids | 10-inch 8-mile pipeline to Ekofisk R |
| Export, gas | 12-inch 8-mile pipeline to Ekofisk R |
| Design contractor | Brown and Root |
| Jacket fabrication | NAPM Vlissingen |
| Deck fabrication | RDL Methil |
| Accommodation | 48 |
The design production capacity was 4,100 Nm3/day oil and 1 million Nm3/day gas. Initial separation was at 515 psia (35.5 bar). Process facilities included gas dehydration and oily water treatment. [1]
Production from the Edda field was by natural depletion. From 1988 gas from Tommeliten Gamma was used as gas lift for the Edda wells. The oil, NGL (natural gas liquids)and gas production profile of the Edda field is as shown. [2]
| Year | Oil (million standard m3 oil equivalent | NGL (MSm3OE) | Gas (MSm3OE) |
|---|---|---|---|
| 1979 | 0.049088 | 0.002244 | 0.010064 |
| 1980 | 1.260264 | 0.084601 | 0.420312 |
| 1981 | 0.717792 | 0.071256 | 0.408622 |
| 1982 | 0.423624 | 0.055091 | 0.296568 |
| 1983 | 0.291055 | 0.044767 | 0.200605 |
| 1984 | 0.231917 | 0.029223 | 0.133306 |
| 1985 | 0.19199 | 0.022817 | 0.089882 |
| 1986 | 0.139436 | 0.01308 | 0.051593 |
| 1987 | 0.049961 | 0.00408 | 0.014713 |
| 1988 | 0.079292 | 0.006468 | 0.018187 |
| 1989 | 0.170931 | 0.014284 | 0.044442 |
| 1990 | 0.178578 | 0.015096 | 0.049031 |
| 1991 | 0.144094 | 0.009506 | 0.037357 |
| 1992 | 0.168869 | 0.009709 | 0.042032 |
| 1993 | 0.136341 | 0.007884 | 0.032994 |
| 1994 | 0.136903 | 0.007414 | 0.031291 |
| 1995 | 0.145824 | 0.007139 | 0.031132 |
| 1996 | 0.138113 | 0.006296 | 0.031357 |
| 1997 | 0.103684 | 0.005044 | 0.020162 |
| 1998 | 0.059554 | 0.003026 | 0.012671 |
Over this period, Edda produced 30.3 million barrels of oil, 1.97 million scm of gas and 21 000 tonnes of NGL. [4]
Edda ‘C’ ceased in production in 1998 and the installation was removed from the field in 2012. [2]