7125/4-2

General

The 7125/4-2 Nucula Appraisal well was drilled in the Måsøy Fault Complex in the Barents Sea. The objective was to prove oil or gas in the Nucula B segment, with the Kapp Toscana Group sands as primary target and the lower Kobbe Formation as secondary target.

Operations and results

Appraisal well 7125/4-2 was spudded with the semi-submersible installation Polar Pioneer on 7 November 2008 and drilled to TD at 1750 m in the Early Triassic Klappmyss Formation. No shallow gas was observed. No significant problem was encountered in the operations. The well was drilled with seawater and hi-vis pills down to 503 m and with Glydril mud from 503 m to TD.

The Kapp Toscana Group was encountered at 930 m, under 40 m of Late Jurassic Hekkingen Formation shale. Hydrocarbons were observed in the Kapp Toscana Group down to an OWC at 946 m. MDT pressure points indicated a pressure drop of up to 0.4 bar in the oil zone across the delineating fault between segments C and B. The top reservoir exhibited a similar low net to gross as seen in the first well. Deeper in the Kapp Toscana Group and top Snadd Fm, however, thicker water bearing channel sandstones were observed. Weak oil shows were recorded from 1281 to 1290 m in the base of the Snadd Formation, and from 1536 to 1560 m in the Kobbe Formation.

No cores were cut in the well. The MDT toll was run for pressure measurements, water and oil samples. Oil samples, both 2 3/4 gallon and 18 Gallon samples, was recovered from 940 m, while water samples were recovered from 946.5, 976.4, and 1027.9 m. Due to the good reservoir properties the fluid samples were collected with low drawdown. The