Troll B, a floating process and accommodation platform with concrete hull, and Troll C, a floating process and accommodation platform with a steel hull, produce from thin oil-bearing layers in the Troll West reservoir.
The thin oil layer is between 22 and 26 meters in the Troll West oil province and 11 and 13 meters in the Troll West gas province.
In order to recover oil from the thin layer, it has been necessary to develop advanced drilling and production technology.
All of the more than 110 production wells to be drilled in Troll Oil are horizontal wells.
This entails drilling in two phases. First, down to the reservoir, which lies at 1,600 meters beneath the sea bottom, and then to 3,200 meters in a horizontal direction through the reservoir.
A total of 28 of the wells are called multi-lateral wells, which have two or three horizontal sections that radiate out from a conjunctive point in the reservoir.
