7122/7-7 S

General

Well 7122/7-7 S was drilled as an appraisal well on the western segment of the Goliat field on the south-east margin of the Hammerfest Basin in the Barents Sea. The Goliat Field produces hydrocarbons from the Realgrunnen Subgroup, the Snadd Formation, and the Kobbe Formation. Primary objective was to test the hydrocarbon bearing potential of the Tubåen and the Fruholmen formations of the Realgrunnen Subgroup. Secondary objective was the Snadd Formation.

Operations and results

An 8 1/2" pilot hole was drilled from seabed to 489 m due to shallow gas warning. No shallow gas was observed. Appraisal well 7122/7-7 S was spudded with the semi-submersible installation West Hercules on 28 November 2018 and drilled to TD at 1330 m (1272 m TVD) m in the Late Triassic Snadd Formation. Operations proceeded without significant problems. The well was drilled with seawater and hi-vis pills down to 615 m and with EMS 4600 oil-based mud from 615 m to TD.

The Tubåen Formation was found gas bearing from 1166 to 1172.5 m (1123,5 to 1132 m TVD) with an oil rim down to an ODT at 1177 m (1134 m TVD). The Fruholmen Formation held oil from 1196 m (1151 m TVD) to the OWC at 1224 m (1176 m TVD). The OWC in Fruholmen Formation is clearly defined by pressure points. The Snadd Formation was found water bearing with weak shows. The pressure data show it is likely that Tubåen and Fruholmen are hydraulically separated and that the Goliat West compartment drilled by this well is overpressured compared to the rest of the Goliat field. Shows in the Realgrunnen Subgroup were described as weak yellow direct fluorescence, slow poor streaming and moderate bluish white crush cut. Shows in the Snadd formation were described as patchy weak yellow direct fluorescence,