Goliat

Location and Geology

The Goliat oil and gas field is located in the Barents Sea, approximately 85 kilometers northwest of the city of Hammerfest, Norway. It is situated within Production License 229 and is the first oil-producing field north of the Arctic Circle in this region.
The field is in water depths of 360-420 meters.
The reservoirs are found in Triassic sandstones of the Kapp Toscana Group (Realgrunnen subgroup) and the Kobbe Formation, with additional minor oil discoveries in the Snadd and Klappmyss formations. The reservoirs lie at depths of 1,100 to 1,800 meters and have a complex and segmented structure.

The Goliat field has two main reservoirs: the Realgrunnen reservoir at about 1,100 meters below sea level and the Kobbe reservoir at about 1,800 meters below sea level. Both reservoirs contain oil with overlying gas caps.
The estimated recoverable reserves include approximately 180 million barrels of oil, 8 billion cubic meters of gas, and 0.3 million tonnes of natural gas liquids (NGL).

The field was discovered in 2000, and the plan for development and operation (PDO) was approved by the Norwegian Parliament in June 2009. Production started on March 12, 2016.
The field is developed using a cylindrical floating production, storage, and offloading (FPSO) facility called Sevan 1000 FPSO. This FPSO is equipped with advanced technologies to handle the harsh Arctic environment and has a capacity to store 1 million barrels of oil.
The FPSO is tied back to eight subsea templates with a total of 32 well slots. The production system includes 22 wells (12 oil producers, 7 water injectors, and 3 gas injectors).
The daily production capacity is approximately 100,000 barrels of oil per day, with gas production also significant. Produced gas is re-injected into the Kobbe reservoir, and future gas export is planned via the Snøhvit pipeline to the LNG processing facility at Melkøya near Hammerfest.

The field is produced using water injection as pressure support, with additional pressure support from the reinjection of produced gas. This strategy helps maintain the reservoir pressure and optimize oil recovery.

The Sevan 1000 FPSO is a geostationary unit with a hull diameter of 90 meters, 25 riser slots, and 14 mooring lines. It weighs about 22,500 tons and can accommodate 120 people on board. The FPSO has a crude storage capacity of 950,000 barrels and can export oil to shuttle tankers at a rate of 8,000 cubic meters per hour.
Key contractors involved in the project include:
- Aker Solutions: Engineering, procurement, and construction of the subsea production system.
- Hyundai Heavy Industries: Fabrication of the FPSO.
- Technip: Installation of flowlines, riser systems, subsea templates, and umbilicals.
- ABB: Electrical, automation, instrumentation, and telecommunications systems for the FPSO.
- Sevan Marine: Project and engineering management for the FPSO.

The Goliat FPSO is designed with several environmental features, including advanced oil spill response systems and power supply from shore via subsea power cables, which reduces CO2 emissions by 50% compared to alternative solutions.
The platform is fully winterized to operate in the harsh Arctic conditions, with a design operating limit of -18°C (-0.4°F) and features to prevent icing from seaspray and fog.

The field is operated by Eni Norge AS (now part of Var Energi AS), which holds a 65% stake. Equinor Energi AS (formerly Statoil) holds the remaining 35%.

Production started in March 2016, and the field is expected to be in production for up to 15-20 years. Despite initial production regularity issues, continuous maintenance and modifications have improved the facility's performance. Future plans include infill wells and potential gas export solutions to extend the field's lifetime.

The development of the Goliat field has had significant economic and social impacts on northern Norway. Regional suppliers have contributed substantially to the project, and Eni has established an operations organization in Hammerfest, employing local personnel.