Statoil has completed drilling and logging of exploration well 6507/3-3 and sidetracks 3A and 3B as operator for production licence 159, covering block 6507/3 about 170 kilometres off the coast of northern Norway.
The wells have been drilled on the C-fangst structure, which lies just north of BP Amoco's Skarv discovery. The water depth in the area is 392 metres.
Well 6507/3-3 was drilled to a total depth of about 3,800 metres below sea level and terminated in Lower Jurassic rocks. The well proved gas, but failed to establish the hydrocarbon/water contact.
To explore the downflank potential of C-fangst, the licensees drilled the 6507/3-3A and 3B sidetracks on an eastern segment of the structure. They proved gas in Jurassic sands, but it is too early to exclude the possibility that the structure also contains oil.
Drilling took longer than planned because of certain rig-specific technical problems and complex well paths. Drilling sidetracks has provided extensive information on the structure which will reduce the need for appraisal wells.
No production tests were carried out in the wells, but extensive data were gathered which will form the basis for further field development. About 220 metres of cores have been taken.
It is hard to give an secure estimate of the size of discoveries in this area, since hydrocarbon contacts vary and reservoirs are difficult to map in detail.
Results from the drilling will now be evaluated as a basis for more detailed calculation of local resources. The wells have yielded important information about the total potential of the area.
Depending on the outcome of this assessment and the area's commercial potential, a progress plan and work programme will be considered for possible further development of the discovery.
The PL 159 licensees will evaluate a unitised development of C-fangst and Skarv as well as utilisation of the established infrastructure in the area. This includes the Norne and Heidrun installations and the gas pipelines due to link these fields with the Åsgard Transport trunkline.
Drilling of the wells was performed by Byford Dolphin, which is now moving to the Yme field in the North Sea to drill production wells.
Awarded in part B of Norway's 12th offshore licensing round, PL 159 has the following licensees:
Statoil (operator) 50 per cent
(State's direct financial interest 20 per cent)
Enterprise Oil Norwegian 40 per cent
Saga Petroleum 10 per cent.