Claymore

Location and Geology

The Claymore oil field is situated in Block 14/19 on the United Kingdom's Continental Shelf, approximately 161 km (100 mi) northeast of Aberdeen in the Central North Sea. The field's coordinates are 58°27′N 0°15′W / 58.450°N 0.250°W.

Discovery and Development

The Claymore field was discovered in 1974 by Occidental of Scotland with the well 14/19-2, which penetrated 158 meters of oil sand at a depth of 2,459 meters subsea. The field is subdivided into main, central, and northern areas, each with different geological characteristics. Production comes from Upper Jurassic paralic and turbidite sandstones in the main area, lower Cretaceous turbidite sandstones in the northern area, and Permian carbonates and Carboniferous sandstones in the central area.

Production

First oil production from the Claymore field began in November 1977 and was exported to the Flotta Terminal via a 30-inch pipeline. The field reached its peak production in 1984, producing 5.25 million tonnes of oil and 60,000 tonnes of Natural Gas Liquids. The oil in place has an API Gravity of 26–33° and a gas oil ratio of 100–400 standard cubic feet per barrel, with a sulfur content of 1.8%.

Infrastructure

The field is developed through a large steel jacket platform standing in 110 meters of water. In addition to the production platform, a separate accommodation platform (CAP) was installed in 1995 and linked to the existing Claymore Production Platform (CPP) by a 106-meter bridge. The production platform also supports production from the Scapa, Golden Eagle, and Tartan fields. Fluid production is supported by gas lift and significant water injection, with two subsea water injection templates installed in 1981 and 1985.

Operations and Facilities

The Claymore installation includes 32 platform oil production wells, four platform water injection wells, five subsea Scapa oil production wells, and 17 subsea water injection wells. Fluids are separated in two horizontal vessels operating in parallel, plus a dedicated Scapa separator. Produced water is treated in hydrocyclones and a degasser vessel prior to overboard disposal. The platform also provides 'up and over' transportation facilities for the Golden Eagle field, with well fluids transported to the Claymore CPP platform for separation and co-mingling with Claymore fluids.

Ownership

The original licensee and operator of the Claymore field was Occidental of Scotland. In May 1991, Occidental sold its North Sea interests, including Claymore, to Elf Aquitaine. Elf later sold the Piper, Claymore, and Saltire platforms in 1999. Talisman Energy acquired a major stake in the Claymore field in 2000 and again in 2004. Following Talisman's acquisition by Repsol in 2014, the Claymore installation is currently owned and operated by Repsol Sinopec Resources UK.

Techno-Economic and Environmental Considerations

The Claymore field has been the subject of various techno-economic studies, particularly focusing on enhanced oil recovery (EOR) and carbon capture and storage (CCS) technologies. These studies evaluate the economic viability and environmental impact of CO2-EOR and CCS in the North Sea, including the Claymore field.

Current Status

As of the last available updates, the Claymore field continues to operate with a complex setup that includes multiple platforms and subsea wells. The field's production capacity and facilities are managed to optimize oil recovery while adhering to environmental and safety standards.