Ekofisk Field

If compaction occurs as a result of production careful monitoring is required. The Ekofisk Field in the Norwegian North Sea made headlines when, as a result of hydrocarbon production, the pores of the fine-grained carbonate reservoir collapsed and the platforms on the seabed started to sink. The situation was later remedied by inserting steel sections into the platform legs. Compaction effects are also an issue in the Groningen gas field in Holland where subsidence in the order of one meter is expected at the surface. 

Sr/ Sr ratios within the Ekofisk Field as indicating that the strontium in the pore waters was derived from the Chalk itself as they closely matched values from primary calcite and contemporary seawater. The Sr/ Sr ratios from the Joanne Field vary from ca. 0.7088 to 0.7096 and are significantly higher than the value of ca. 0.7079 for Late Cretaceous seawater (no primary calcite was analysed for comparison). This suggests the strontium in the Joanne Field pore waters is unlikely to have been derived predominantly from the Chalk. 

The comparison of the numerical results with the total stress conditions are those of Ekofisk field i.e. 

Teufel L.W. Farrel H.E. 1990. In situ stress and natural fracture distribution in the Ekofisk field, North Sea. Proc. Third North Sea Chalk Symposium, Copenhagen. 

High flow rate, which above a certain level causes removal of FeCOs from the tube wall and thereby activates the steel surface. Experienee from Ekofisk field in the North Sea indicates that erosion corrosion occurs when the fluid veloeity on top of the well exceeds 7-10 m/s. Figure 8.12 shows a similar result from a gas/condensate well [8.28]. 

Milestones in the Study of Soils, Marine Sediments, and Marine Geotechnics Late 1960s—Ekofisk field in North Sea discovered... 

Service Jack 1 (delivery of an accommodation module and other equipment on the Ekofisk field). 

The audit of the Service Jack 1 project is the only one of the fourteen reports to focus on the design and construction phase. Some new cranes, an office module and a larger accommodation module at Ekofisk field were to be constructed. A large part of the actual work was to be done in Indonesia. The inspection was conducted by interviews and documentary research at the supplier Master Marine s project offices in Oslo and Singapore, and through a visit to the production plant... 

Intensified exploitation of gas and oil required, on the one hand, larger investments by companies and. on the other hand, promised profits as well. Risks to be expected in connection with regional employment and economic development prospects had to be calculated. Possible effects on the environment are not difficult to imagine now, in view of the accident in the Ekofisk field in the North Sea and various incidents with supertankers during the recent past. Effects on fishing and tourism may be mentioned in this connection, and legal aspects of national and international. scope are certainly not the least of the problems. 

Snow, S.W. Hough, E.V. "Field and Laboratory Experience in Stimulating Ekofisk Area North Sea Chalk Reservoirs," SPE paper 18225 1988 SPE Annual Technical Conference and Exhibition, Houston. 

Physical properties. Most of the petroleums tested from the Chalk reservoirs in the Judy and Joanne Fields are undersaturated black oils. Gas-oil ratios are generally in the range 2000 to 2500scf/bbl and bubble points are approximately 1000 to ISOOpsi below present-day reservoir pressures (Table 2). In the Judy structure, well 30/7a-4a tested gas caps in both the Ekofisk and Tor reservoirs. Petroleum tested from the Tor in 30/7a-6 also had a high GOR (4322 scf/bbl) and PVT analysis confirmed the fluid as a gas-condensate (Pd = 7185psi). However, the dew point pressure is very close to the reservoir pressures obtained from RFT pressure measurements (7150-7200 psi). Furthermore, flow rates were very low and so the test results may not be valid. 

Introduction. The existence or absence of separate compartments within the Ekofisk and Tor reservoirs is a critical issue in determining reserves distribution and optimal production methods. Initially, a fault compartmentalized reservoir model was used to account for the southwesterly deepening oil-water contacts recorded in appraisal wells in the Joanne Field. Within the Ekofisk reservoir, the observed oil-water contact deepens by 280 ft from 9920 ft (tvdss) in 30/7a-l to 10200 ft in 30/7a-3 in the Tor, the oil-water contact deepens by almost 400ft from 10276ft in 30/7a-l to 10675 ft in 30/7a-3. Following completion of development well drilling, the current model incorporates single tilted oil-water contacts in both the Ekofisk and Tor. 

Smalley, P. C., L0N0y, A. Raheim, A. 1992. Spatial Sr/ Sr variations in formation water and calcite from the Ekofisk chalk oil field implications for reservoir connectivity and fluid composition. Applied Geochemistry, 7, 341—350. 

Houghton CJ, Westermark RV. Downhole corrosion mitigation in Ekofisk (North Sea) field. In CO2 Corrosion in Oil and Gas Production, Selected Papers, Abstracts, and References. Houston NACE Task Group T-1-3,1984. 

There have been a number of recent and well publicised accidents in which human error has played a prominent part. At Three Mile Island a combination of poor display design, bad maintenance and operator error led to the reactor core becoming uncovered and the release of radioactivity into the atmosphere. At the Ekofisk oil field incident a blowout preventer was installed upside down which resulted in an accident, following which widespread environmental pollution ensued. In both these cases the overall losses have been estimated in tens and hundreds of millions of pounds. These and similar incidents have brought sharply into focus the need to include an appraisal of human reliability and the factors which affect it when considering the safety performance of both large and small scale systems of work. ... 

Alexander L. Kielland was a Norwegian semisubmersible rig/platform in the Ekofisk oil field, Norwegian continental shelf, about 235 miles east of Dundee, Scotland, United Kingdom. The rig/platform was named after a Norwegian writer, and it was owned by the Stavanger Drilling Company of Norway. At the time of the occurrence of the disaster, the rig/platform was hired by the United States Company called Phillips Petroleum. 

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