9/3-2

General

Wildcat well 9/3-2 is located east in the Egersund Basin in the North Sea.The well was drilled as part of the Production License 316. PL 316 is a stratigraphic license that applies to all levels from 200 meter below base Jurassic and up to seafloor where Triassic is present, and all levels over base Jurassic where Triassic is not present. The main objective was to determine the presence of commercial volumes of hydrocarbons within the Sandnes formation of the Aimee prospect, which straddles Blocks 9/3 and 9/2. A secondary objective was to acquire reservoir pressure data and geological data, to improve reservoir understanding for any future field development.

Operations and results

Well 9/3-2 was spudded with the jack-up installation Mærsk Giant on 23 October 2005 and drilled to TD at 3154 m in the Late Triassic Skagerrak Formation. Operations took significantly longer time than planned due mainly to bad weather and open hole problems. The well was drilled with seawater down to 219 m, with seawater/KCl mud from 219 m to 507 m, with seawater only again from 507 m to 1149 m, and with "Enviromul" oil based mud from 1149 m to TD.

There were no sand development above Jurassic level. At 1970 m the well encountered a 690 m thick Late Jurassic Boknfjord Group described mainly as claystone, including a 104 m thick Tau Formation with top at 2503 m. The Sandnes Formation reservoir was penetrated at 2660 m (2612.6 m TVD SS), 29.4 m high from the prognosis, however no hydrocarbons were encountered. The Sandnes Formation had a gross interval of 117.6 m and a net interval of 81.84 m, with a net/gross of 0.69. Water wet Bryne reservoir was also encountered, at 2777.9 m (2730.2 m TVD SS). It had a gross interval of 290.02 m with a net interval of 71.93 m, giving a net/gross of 0.25. There were no shows in the well other than a very slow pale milky white cut, with a pale white residual in the Bryne Formation between 2810 - 2830 m, t