The wells were drilled by the Deepsea Yantai drilling facility. Photo: Odfjell Drilling

Neptune Energy Norge AS, operator of production licence 153, has concluded the drilling of appraisal wells 35/9-16 S and 35/9-16 A on oil and gas discovery 35/9-3 (Hamlet).

The wells were drilled about 7 kilometres north of the Gjøa field in the North Sea, and 58 kilometres west of Florø.

The 35/9-3 discovery was proven in reservoir rocks from the Early Cretaceous with generally poor reservoir quality (the Agat Formation) in 1997. Before wells 35/9-16 S and 35/9-16 A were drilled, the operator's resource estimate for the discovery was between 0.62 and 1.12 million Sm3 of recoverable oil equivalent.

The objective of the appraisal wells was to clarify the reservoir quality and hydrocarbon column in the southern part of the Hamlet structure.

Well 35/9-16 S encountered a 58-metre gas column and a 34-metre oil column in the Agat Formation in sandstone layers totalling 92 metres with moderate to poor reservoir quality. The gas/oil contact was encountered at 2624 metres below sea level.

Well 35/9-16 A encountered a 35-metre oil column in the Agat Formation in sandstone layers totalling 115 metres with good to poor reservoir quality. The oil/water contact was encountered at 2663 metres below sea level.

The preliminary calculation of the size of the discovery is between 2.2 and 3.4 million Sm3 of recoverable oil equivalent.

The licensees will consider tying the discovery into existing infrastructure in the Gjøa field and will assess the discovery alongside other nearby discoveries and prospects as regards further follow-up.

The wells were not formation-tested, but extensive data acquisition and sampling was undertaken.

These are the 11th and 12th exploration wells in production licence 153. The licence was awarded in the 12th licensing round in 1988.

Appraisal well 35/9-16 S was drilled to a vertical depth of 2720 metres below sea level and was terminated in the Sola Formation in the Early Cretaceous.

Appraisal well 35/9-16 A was drilled to a vertical depth and measured depth of 2790 metres and 3015 metres below sea level, respectively, and was terminated in the Sola Formation in the Early Cretaceous.

The water depth is 358 metres and the well has been plugged and abandoned. The wells were drilled by the Deepsea Yantai drilling facility, which will now drill production wells in production licence 586 in the Norwegian Sea, where Neptune Energy Norge AS is the operator.

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