Containing about 40 percent of total gas reserves on the Norwegian continental shelf (NCS) the Troll field represents the very cornerstone of Norwegian gas production. The field consists of the main Troll East and Troll West structures in blocks 31/2, 31/3, 31/5 and 31/6 in the North Sea.
The Troll field is located in the northern part of the North Sea, about 65 kilometres west of Kollsnes near Bergen.
Troll is also one of the largest oil fields on the NCS. In 2002 the oil production totalled more than 400,000 barrels per day.
Equinor is the operator of the Troll A, B and C platforms and the landfall pipelines, whereas Gassco is the operator for the gas processing plant at Kollsnes on behalf of Gassled. Equinor is the technical service provider for Kollsnes operations. The enormous gas reservoirs 1,400 metres below sea level are expected to produce for at least another 70 years.
Proven in 1979
Norske Shell was appointed operator when block 31/2 was awarded in April 1979. A large gas discovery with an underlying oil zone was proven later the same year. The block was declared commercial in 1983.
The neighbouring blocks were awarded to then Statoil, now Equinor, Norsk Hydro and Saga Petroleum in 1983.
Block 31/2 contains 32 percent of the Troll field’s reserves, whereas the three other blocks hold the remaining 68 percent.
The licence terms for block 31/2 specified that we could take over the operatorship of this acreage eight to 10 years after the field was declared commercial.
In 1985 the licences were unitised, allowing Troll to be developed as a single unit. We took over the operatorship of Troll Gas on 19 June 1996, whereas Hydro started production from Troll Oil in the autumn of 1995.