34/2-2 R

General

Exploration well 34/2-2 is located a northwestern part of the Tampen Spur area. It was intended to be the first well to test the reflections below the Base Cretaceous (Kimmeridgian) Unconformity on a seismically defined, northerly trending west-northwest dipping fault block. The well was located near the apex of the structure at the Base Cretaceous level, but down-dip with respect to deeper stratigraphy. Primary targets were the Middle Jurassic Brent Formation and the Early Jurassic/Triassic Statfjord Formation. Secondary targets were possible Early Tertiary and Late Jurassic sandstones. Planned TD was 4300 m Sub Sea.

Operations and results

Well 34/2-2 R was spudded with the semi-submersible installation Sedco 703 on 12 December after the first entry 34/2-2 had been abandoned for technical reasons. The well was drilled to TD at 4074 m in the Late Triassic Statfjord Formation, Raude Member. Bad weather conditions during wintertime delayed the drilling progress on many occasions. While drilling the 36" hole section some problems were encountered due to boulder beds. An abnormally high wave hit the rig on 16 January, damaging the living quarters. The rig had to be shut down for repairs for eleven days. Otherwise, drilling of the sedimentary sequence below the 30" casing to TD did not cause major problems. The well was drilled with spud mud/hi-vis pills down to 499 m, with CMC and bentonite from 499 m to 810 m, and with lignosulphonate mud from 810 m to TD.

The Brent Formation was not developed in the well and the reservoir conditions in the Statfjord Formations were found to be poorer than expected. No indications of hydrocarbon accumulations were seen. Trace shows were recorded in the Cretaceous in sandstone stringers from 2405 m to 2700 m, in siltstones from 2903 m to 3000 m, and in sandstones from 3200 m to 3282.5 m. From 3282.5 m to 3297.5 m there was a good show in a limestone bed. No oil shows were reported