17/6-1

General

Well 17/6-1 was drilled on the Svaneøgle prospect located in the Ling Depression in the North Sea. The primary objective was to test the hydrocarbon potential of the Middle Jurassic Sandnes and Bryne Formations. Secondary objectives were to prove sand development and hydrocarbons in the Upper Jurassic Sauda Formation, and to prove reservoir presence and hydrocarbons in the Early Jurassic/Late Triassic Gassum/Skagerrak formations. A tertiary objective was to acquire quality data across the Balder Formation.

Operations and results

Wildcat well 17/6-1 was spudded with the semi-submersible installation West Alpha on 5 January 2011 and drilled to TD at 3065 m in the Late Triassic Skagerrak Formation. No significant problem was encountered in the operations. The well was drilled with seawater and hi-vis sweeps down to 712 m and with Glydril mud from 712 m to TD.

Top of the main target, Sandnes and Bryne formations was penetrated at 2630 m. The formations had a total gross reservoir thickness of 96 m containing sandstones interbedded with claystones and thin coal beds. Reservoir properties were poorer than expected in the Sandnes Formation, and only minor amounts of hydrocarbons were encountered in the uppermost part. The Bryne Formation had a better reservoir sand development, but was found to be water bearing. The secondary target Sauda Formation had no sand/reservoir development. The Gassum/Skagerrak Formation showed minor amounts of sandstones, but contained no hydrocarbons. The Balder Formation showed no reservoir development and had no indications of hydrocarbon shows. Two cuttings samples from the Sandnes Formation showed weak cut fluorescence (no core samples were taken); otherwise no oil shows were recorded in the well.</sp