7234/6-1

General

Well 7234/6-1 was drilled to test the Stangnestind prospect on the western flank of the Fedynsky High, 12 km from the Russian border. The primary objective was to explore the hydrocarbon potential of the untested play in Late Carboniferous to Early Permian carbonate intervals of the rn Formation, Gipsdalen Group.

Operations and results

An 8 1/2" pilot well, 7234/6-U-1, was spudded on 31 May 2021, 25 m west of the main bore to check for shallow gas, check out unknown shallow lithology in the Lower Cretaceous wedge and to serve as a data acquisition well in the shallow part of the stratigraphy at Stangnestind. The pilot hole was drilled to 672 m. No shallow gas or water flow was detected and a safe setting depth for the 20" casing in the main bore was established.

Wildcat well 7234/6-1 was spudded with the semi-submersible installation Deepsea Nordkapp on 1 June 2021 and drilled to TD at 4035 m (4041 m loggers depth) m in the rn Formation of Late Carboniferous to Early Permian age. Severe losses up to 60 m3/h occurred at TD. The well was stabilized, and logging commenced successfully. The well was drilled with seawater and hi-vis pills down to 630 m, with KCl water-based mud from 630 m to 3618 m, and with BaraECD 2.2 oil-based mud from 3618 m to TD.

The well encountered dolomitised limestone reservoir (intra rn Formation) at 3915 m and detected a 57 m column of dry gas. The gas contained 13 % CO2 and 15.9 % H2S. No wells on the Norwegian continental shelf have previously seen any H2S level close to this. 26 m of the reservoir zone had relatively good reservoir properties (average porosity of 14%). Although the gas-water contact was not seen on logs, an MDT-sample at