7222/11-1

General

The 7222/11-1 Caurus well was drilled on the Bjarmeland Platform in the Barents Sea. The objective of the well was to prove hydrocarbons in the Caurus prospect in prognosed reservoir intervals in Snadd Formation of Carnian age and in Kobbe formation of Anisian age.

Operations and results

A pilot hole, 7222/11-U-1, was drilled 13 m south-west of the main well location. No shallow gas was found in the pilot hole.

Wildcat well 7222/11-1 was spudded with the semi-submersible installation Polar Pioneer on 24 August 2008 and drilled to TD at 2658 m (2625 m TVD) in the Middle Triassic Kobbe Formation. The 8 1/2" hole was drilled to 2082 m where the well started to lose mud to the formation due to drilling induced fractures, which were observed on the FMI logs. The well was plugged back, and a technical sidetrack T2 with reduced mud weight was drilled from 1252 m to TD. A second technical sidetrack T3, was drilled to core the Kobbe Formation. The well was drilled with seawater and hi-vis pills down to 606 m and with Glydril WBM from 606 m to TD.

The Caurus well penetrated a Quaternary section of 72 m and a Jurassic section of 185 m before drilling into rocks of Triassic age, Snadd Formation, at 636 m. The well proved gas in two levels in the Snadd Formation; in two thin sandstones of Early Norian age at top Snadd level, and in sandstones of Late Carnian age at 771 m with a gas/water contact at 785 m. Good oil shows were seen under the contact from 788 to 798 m. The gas bearing Snadd Formation sandstones had very good reservoir properties. In the Kobbe Formation oil and gas was found at two levels; oil in channelized san