Sigrun delineation appraisal well completed

Source: press release, 16 August 2018

illustration: NPD
illustration: NPD

The Norwegian Petroleum Directorate reports that Equinor Energy AS, operator of production licence 025, has concluded the drilling of appraisal well 15/3-11 on the 15/3-4 (Sigrun) oil and gas discovery.

The well was drilled about 10 kilometres southeast of the Gudrun field in the North Sea, and about 225 km west of Stavanger. The objective of the well was to delineate the 15/3-4 discovery in three reservoir zones in the Middle Jurassic (the Hugin formation).

The discovery was proven in reservoir rocks from the Middle Jurassic in the Brent group in 1982. Before well 15/3-11 was drilled, the operator’s resource estimate for the discovery was between 0.3 – 1.4 million standard cubic metres (Sm3) of recoverable oil equivalents.

The well encountered a total oil column of about 35 metres in the Hugin formation, of which about a 15-metre thick sandstone layer with poor to moderate reservoir quality. The oil/water contact was not encountered. Preliminary estimates of the size of the discovery after the delineation well are between 1.1 and 2 million Sm3of recoverable oil equivalents.

The well was not formation-tested, but extensive data acquisition and sampling have been carried out.

The licensees in production licence 025 will assess the profitability of the discovery regarding a potential development over the Gudrun field.

This is the ninth exploration well in production licence 025. The licence was awarded in licensing round 2-A in 1969.

Appraisal well 15/3-11 was drilled to a vertical depth of 3991 metres below the sea surface and was terminated in the Sleipner formation in the Middle Jurassic. Water depth at the site is 109 metres. The well has been permanently plugged and abandoned.

The well was drilled by the Deepsea Bergen which will now drill wildcat well 35/10-4 S in production licence 630 in the northern part of the North Sea, where Equinor Energy AS is the operator.