THE UK Continental Shelf has nine mobile rigs (four semi-submersibles and five jack-ups) currently active on four exploration and five appraisal wells in the Northern, Central and Southern North Sea.
Activity in the East Irish Sea Basin will resume this month, but E&A (exploration and appraisal) activity in the West of Shetland sector in 2010 has yet to begin.
E&A is bolstered by the floaters, Ocean Nomad (from stack) and Stena Spey (from CNS development work), mobilising to drill in the Northern sector.
Eight exploration spuds and five appraisals bring the 2010 well start total to 13 and, although imminent, still no sidetrack activity has been started.
On the field-development front, drilling activity is ongoing on 14 development operations, six with mobile rigs (five semis and a jack-up) and the remainder utilising platform derrick facilities.
E&A activity in the Northern North Sea stepped up during April with three wells classed as active. Total’s Laphroaig well, 3/15-13A, being worked by the Sedco 714, needed a re-spud, and there were two new starts: Stena Spey drilling well 210/25a-10 (an appraisal of Tern North for TAQA), and Valiant’s Tybalt exploration well, 211/8c-4, being pursued by the Ocean Nomad.
There is no change in the Central North Sea, where two wells remain active: Nexen-operated Bugle North appraisal well 15/23d-15 with the semi-submersible, GSF Arctic 4, and Ithaca’s Stella appraisal well 30/6a-8 with the jack-up, Galaxy 2, where a geological sidetrack will be initiated following the testing of 2,850 barrels per day of light oil from the objective Palaeocene sands.
Activity in the Southern North Sea remains static with four jack-ups operating. GDF SUEZ Cygnus appraisal well 44/11a-4, with the Ensco 100, has tested 28million cu ft per day of gas from the Leman Sandstone.
Noble Julie Robertson is operating on Centrica’s Olympus exploration well 48/12e-11; GSF Labrador remains on Dana’s Platypus prospect well 48/1a-5, now likely to be testing following the discovery of good-quality gas-bearing sands in the Leman reservoir, and ATP has the Noble Byron Welliver, which mobilised from Esjberg port, in Denmark, to drill well 43/22a-3, an appraisal of the Carboniferous reservoir in the north-west part of the Kilmar field.
In the East Irish Sea, the last well drilled by the jack-up, Ensco 92, during a year-long tenure in the basin has been abandoned. BHP’s well 110/13b-21 on the Bel Air/Douglas East prospects was abandoned after 32 days, the rig moving to port on the north-east coast of England.
The next activity in the EIS is expected to be Serica’s Conan well on block 113/27c using the jack-up, Ensco 80, set to commence operations early this month.
Simon Robertshaw’s column is courtesy of drilling analysts Hannon Hannon Westwood