Offshore staff
OSLO -- Norske Shell has completed an appraisal well on its Gro gas discovery in the Norwegian Sea, with disappointing results.
Gro was discovered last year in production license 326 in Upper Cretaceous reservoir rocks (the Springar formation). Well 6603/12-1 was drilled around 350 km (217 mi) west of Sandnessjøen.
Before work started on the appraisal well, 6604/10-1, resource estimates were in the range 10-100 bcm (353-3531 bcf) of recoverable gas, according to the Norwegian Petroleum Directorate (NPD).
The new well proved gas in a 50-m (164-ft) column in the Springar formation in the Upper Cretaceous. NPD says the reservoir rocks are of a more substantial thickness, but reservoir quality was poorer than expected.
Preliminary estimates suggest the find is in the lower range of the original resource estimate. However, the variable reservoir quality and gas saturation, along with the extent of the discovery, mean further studies will be needed to clarify the actual size.
The well was not formation-tested, but extensive data collection and sampling have been performed. Water depth at the site is 1,345 m (4,413 ft). The well will be permanently P&A’d.
The semisub Aker Barents, which drilled the well, now heads to PL 392 in the Norwegian Sea to drill wildcat 6603/5-1, again for Norske Shell.
08/30/2010
