ID: 404
OBJECTID: 404
wlbNpdidWellbore: 409
wlbName: 33/9-4
wlbHistory:

General

Well 33/9-4 was drilled on the Statfjord structure on Tampen Spur in the northern North Sea. The primary objective was to test the northern extension of the Statfjord discovery in the Brent Group.

Operations and results

Appraisal well 33/9-4 was spudded with the semi-submersible installation Norskald on 30 July 1975 and drilled to TD at 3076 m in the Triassic Hegre Group. No significant problem was encountered in the operations. The well was drilled with seawater and spud mud down to 488 m and with Lignosulphonate mud from 488 m to TD.

The objective Brent Group was encountered at 2554.5 meters, 33.9 meters high to prognosis. Measured core porosities in the Brent Group averaged 26 percent. Horizontal liquid permeability ranged from 0.05 to 1100.5 milliDarcy and averaged 2155 milliDarcy. The Brent Group was oil filled down to the oil-water contact at 2611.5 m. This is 2 m deeper than on the southern part of Statfjord Field and constitute an in-well gross oil column of 57 m of which 37 m was calculated as net reservoir with 25.4% average porosity and 24.2% average water saturation. Apart from shows in the oil bearing section an oil show was described on a sidewall core at 2618 m.

Continuous coring was carried out from within the overlying Middle Jurassic shales through the base of the oil/water contact in the Brent sands, from 2547.2 to 2612.5 meters. Of the 56.7 meters cut by nine cores, 50.7 meters (89 percent) was recovered. No fluid sample was taken on wire line.

The well was permanently abandoned on 17 September as an oil appraisal well.

Testing
wlbHistoryDateUpdated: 2016-07-06T00:00:00