MOL Norge AS will reduce resource estimates in the 25/8-19 S (Iving) oil and gas discovery in PL 820S based on results from appraisal wells 25/8-21 S and 25/8-22 S. The wells were drilled about 8 km northwest of 25/8-11 Ringhorne on Balder field in the North Sea, about 200 km west of Stavanger in 127 m of water.
Appraisal wells 25/8-21 S and 25/8-22 S, the third and fourth exploration wells in the license, were drilled to respective measured depths of 2,663 and 2,582 m below sea level, and respective vertical depths of 2,587 and 2,515 m below sea level (OGJ Online Apr. 29, 2021). Both wells were terminated in basement rock.
The primary exploration target for well 25/8-21 S was the oil-water contact in sandstones in the Skagerrak formation. The secondary exploration target evaluation of the petroleum potential in the basement rock reservoir.
The well encountered a 3-m gas column over a 30-m oil column in sandstones of poor-to-good reservoir quality in the Skagerrak formation. Oil was also encountered in a 6-m sandstone layer with moderate reservoir quality in the lower part of the Skagerrak formation. Oil-water contact was not encountered. A separate oil column of about 50 m was encountered in basement rock with poor reservoir quality. Oil-water contact was also not encountered in this rock.
A small-scale formation test was conducted in the Skagerrak formation. The formation test revealed limited flow properties.
The primary exploration target for well 25/8-22 S was to evaluate the petroleum potential in sandstones in the lower part of the Statfjord group and in the Skagerrak formation. The secondary exploration target was to evaluate the petroleum potential in the Heimdal formation and basement rock.
The well encountered a 20-m gas column over a 29-m oil column in sandstones of moderate-to-good reservoir quality in the Skagerrak formation. Pressure data indicate communication in the Skagerrak reservoir between all wells in the discovery. The reservoir quality in the lowermost part of the Skagerrak formation was not sufficient to confirm mobile petroleum. The oil-water contact was not encountered.
A 2-m oil column was encountered in sandstone of good-to-very-good reservoir quality in the lower part of the Statfjord group, and this has been interpreted to be a separate accumulation in relation to 25/8-19 S (Iving). The oil-water contact was encountered at 2,185 m below sea level. The well also encountered oil in thin 2-m sandstones in the upper part of the Statfjord group and in the Heimdal formation (3 m). The reservoir quality in basement rock was not sufficient to confirm mobile petroleum. The well was not formation-tested, but data acquisition and sampling were carried out.
Before the appraisal wells were drilled, resource estimate for the discovery was between 2 and 11 million standard cu m (scm) recoverable oil equivalent in the Skagerrak formation. The well results will adjust resource estimates downward for this formation in 25/8-19 S (Iving), but it is too early to give an updated estimate for the discovery, MOL said.
The wells have been plugged.
MOL Norge AS is operator at 820S (40%) with partners Lundin Energy Norway AS (41%), Pandion Energy AS (12.5%), and Wintershall Dea Norge AS (6.5%).