16/2-20 A

General

Well 16/2-20 A is a geologic sidetrack to well 16/2-20 S. Both well tracks were drilled to test the Torvastad prospect north of the Johan Sverdrup Field on the Utsira High in the North Sea. The primary objective was to investigate the Jurassic - Early Cretaceous sequence with respect to reservoir facies, hydrocarbons, free water level, pressure communication with the Johan Sverdrup Field, and seismic interpretations and depth conversion. Well 16/2-20 A was drilled 800 meters towards west to investigate the presence of oil filled Jurassic reservoir at shallower depth than the S well.

Operations and results

Wildcat well 16/2-20 A was drilled with the semi-submersible installation Island Innovator. Operations started on 21 November 2013 but due to problems with the lower marine riser package (LMRP) and bad weather, actual kick-off was not performed until 12 December 2013. The kick-off point was at 732 m in the primary S well. Equipment failure, mainly related to the LMRP, caused 551 hours no production time for this well, while bad weather caused 725 hours WOW. Only 41% of total rig time was counted as productive. The well was drilled to TD at 2215 m in Granitic basement rock using Aquadril mud from kick-off to TD.

Well 16/2-20 A found a late Jurassic Draupne spiculitic sandstone/siltstone sequence of similar extent and facies as found in well 16/2-20 S, despite indications of a thinning of this sequence interpreted from seismic data. The Statfjord Group sequence is not present and the spiculite rests unconformable on a 57 m Triassic Hegre and Skagerrak Group sequence. Good shows were observed in the sandstones of the Draupne and Skagerrak formations.</spa