Another offshore duster for Equinor
- Exploration & Production
Norwegian operator Equinor has concluded the drilling of two wildcat wells offshore Norway, which has resulted in one dry well and one minor oil discovery.
The wells, named 35/10-4 S and 35/10-4 A, were drilled about ten kilometers southwest of the Vega field in the northern part of the North Sea in production license 630 where Equinor is the operator.
According to a Thursday report by the Norwegian Petroleum Directorate (NPD), the primary exploration target for well 35/10-4 S was to prove petroleum in Middle and Lower Jurassic reservoir rocks (the Brent group and the Cook formation). The secondary exploration target was to prove hydrocarbons in Upper Jurassic reservoir rocks (the Heather formation, as well as to test the reservoir potential in the Palaeocene (Intra Balder sands/the Sele formation).
The well 35/10-4 S encountered the Brent group, about 210 meters thick, whereof effective reservoir rocks of 40 meters of sandstone, mainly with poor to moderate reservoir properties. The Cook formation has a thickness of about 140 meters, whereof effective reservoir rocks of 75 meters, mainly with moderate to good reservoir properties. Both of the primary targets were aquiferous.
In the secondary exploration targets, the Heather formation has thin sandstone layers totaling about ten meters with poor reservoir quality. Traces of oil were proven in one of the lower layers. In the Palaeocene, the well encountered a 17-meter thick aquiferous sand package with good reservoir properties. Data was acquired in the well.
The primary exploration target for well 35/10-4 A was to prove petroleum in reservoir rocks in the Upper Jurassic (the Heather formation). The secondary exploration target was to explore the reservoir properties in Middle Jurassic deposits from the Callovian Age.
The well 35/10-4 A encountered sandstone layers in the Heather formation totaling about 122 meters, mainly with poor reservoir quality. Oil was proven, but the oil/water contact was not encountered. Preliminary estimates show from 0.2 MSm3 to 1.2 MSm3 recoverable oil. The volume range is mainly due to uncertain reservoir quality. A preliminary assessment indicates that the discovery is not currently profitable. The well was not drilled into the secondary exploration target.
Extensive volumes of data were collected in the well.
These are the first and second exploration wells in production license 630, which was awarded in APA 2011.
The well 35/10-4 S was drilled to a vertical depth of 3787 meters below the sea surface, and was terminated in the Amundsen formation in the Lower Jurassic.
The well 35/10-4 A was drilled to a vertical depth of 3427 meters below the sea surface, and was terminated in the Heather formation in the Upper Jurassic.
Water depth is 363 meters. The wells have been permanently plugged and abandoned.
The wells were drilled by the Deepsea Bergen, which then went on to drill wildcat well 6407/11-1 in the Norwegian Sea in production license 751, where Equinor Energy is the operator.
It is worth reminding that the Deepsea Bergen recently drilled another dry well for Equinor. The well was drilled about 15 kilometers southeast of the Njord field and 120 kilometers north of Kristiansund.