Wintershall Dea (Harbour Energy) has proven gas in appraisal well 6507/4-5 S in the Norwegian Sea, 270 kilometres north of Kristiansund.
The preliminary estimate of the size of the discovery in the Lange Formation (“Sabina”) is between 2.7 and 6.2 million standard cubic metres (Sm3) of recoverable oil equivalent. This corresponds to about 17-39 million barrels of oil equivalent.
In the Lysing Formation (“Adriana”), the well confirms the size of the discovery at 4-7 million Sm3 of recoverable oil equivalent, which corresponds to around 28-43 million barrels of oil equivalent.
The well was drilled by the Transocean Norge rig.
Wintershall Dea (Harbour Energy) is the operator of production licence 211 CS, while Petoro, Aker BP and Orlen are the other licensees. The licensees are considering tying the discoveries back to existing infrastructure in the area.
Geological information
Before appraisal well 6507/4-5 S was drilled, the operator’s resource estimate for the primary exploration target was 3-9 million Sm3 of recoverable oil equivalent, while the resource estimate for the secondary exploration target was 4-7 million Sm3 of recoverable oil equivalent.
The primary objective of the well was to delineate the gas/condensate discovery from wildcat well 6507/4-2 S in the Lange Formation (“Sabina”), and to carry out formation testing.
The secondary objective was to delineate the gas/condensate discovery (6507/4-2 S) in the Lysing Formation (“Adriana”).
In the primary exploration target, the well encountered a 41-metre gas column in sandstone rocks totalling 17 metres, with poor to moderate reservoir quality. The gas/water contact was not encountered. The well also encountered two sandstone layers in the Middle and Lower Lange Formation of around 4 and 21 metres, with poor reservoir quality but with traces of hydrocarbons.
In the secondary exploration target, the well encountered a 30-metre gas column in sandstone rocks totalling 23 metres with good to very good reservoir quality. The gas/water contact was encountered at 2897 metres below sea level. Extensive data acquisition and sampling have been carried out.
A successful production test was conducted in the upper part of the Lange Formation. The maximum production rate was 530,000 Sm3 of gas and 80 Sm3 of condensate per flow day through a 28/64-inch nozzle opening.
The appraisal well was drilled to a vertical depth of 4111 metres and a measured depth of 4150 metres below sea level, and was terminated in the Lange Formation in the Lower Cretaceous.
Water depth at the site is 455 metres. Appraisal well 6507/4-5 S has been permanently plugged and abandoned.
Source: Norwegian Offshore Directorate
