7218/11-1

General

Well 7218/11-1 was drilled on the Darwin prospect about 230 kilometres northwest of Hammerfest and 80 kilometres southwest of the 7220/8-1 (Skrugard) discovery in the western part of the Barents Sea. The primary exploration target for the well was to prove petroleum in the Late Cretaceous (Kveite Formation). The secondary exploration target was to prove petroleum in the Paleocene Torsk formation

Operations and results

Wildcat well 7218/11-1 was spudded with the semi-submersible installation Transocean Barents on 5 March 2013 and drilled to TD at 2542 m in the Early Cretaceous Kolmule Formation. A 9 7/8" pilot hole (7218/11-U-1) was drilled to 1155 m to check for shallow gas. No shallow gas or water flow was observed. In the main bore problems occurred as the hole packed off after drilling to 1155 m. A technical sidetrack was performed (7218/11-1 T2), with kick-off at 605 m in the main bore, and further operations proceeded without significant problems. The well was drilled with seawater and bentonite sweeps down to 437 m, with seawater/bentonite sweeps and CMC from 437 m to 1155 m, and with Glydril water based mud from 1155 m to TD. The Glydril mud contain 4-5% glycols.

Reservoir development was not proven in the Kveite formation, and thin, dense sandstone layers were proven in the Torsk formation, as well as traces of gas. The section between 1610 and 1750 in the upper Kolmule Formation is a potential source rock for gas and oil. It has enhanced TOC in the range 2 - 3.5 %wt and Rock-Eval Hydrogen index in the range 200 - 300 mg HC/g TOC. The kerogen in this section is mainly of terrestrial nature, with some algal contribution. In the well location, the section is immature for petroleum generation.