OSLO, Norway – Petroleum Safety Authority (PSA) Norway has sanctioned use of the semisubmersible COSLInnovator for production drilling on the Troll field in the North Sea, using the controlled mud level (CML) method.
The consent applies to the 8½-in. sections in well 31/2-L-22. Statoil previously tested the technique, otherwise known asdual gradient drilling, in another production well at Troll. It allows wells to be drilled in depleted reservoirs when it is no longer possible to drill using conventional methods.
The company is now looking to perform a new pilot study to implement improvements and experiences from the first program, before committing to widespread deployment of the technology.
PSA also has authorized Lundin Norway to use the jackupRowan Viking to drill production wells on the Edvard Grieg field in block 16/1 in the central Norwegian North Sea. Water depth at the site is around 110 m (361 ft).
The field is being developed with a fixed wellhead, accommodation, and production facility.Rowan Viking will drill 15 wells for production and water injection. The program runs until fall 2017, with a break next summer to coincide with installation of seabed facilities.