27/03/2014 Lundin Norway AS, operator of production licence 501, is in the process of completing the drilling of appraisal well 16/3-8 S on the 16/2-6 Johan Sverdrup oil discovery in the central part of the North Sea.
The discovery was proven in Jurassic reservoir rocks in production licence 501 in the summer of 2010. Appraisal well 16/3-8 S was drilled 3.8 kilometres southeast of the discovery well 16/2-6 and 2.8 kilometres west of appraisal well 16/3-4.
The objective of the well was to investigate the reservoir and flow properties of Upper Permian carbonate rocks (Zechstein group) and establish the presence, thickness and reservoir quality of the Upper Jurassic reservoir rocks. Information from this well is important in order to optimise the drainage strategy for this part of 16/2-6 Johan Sverdrup.
Well 16/3-8 S encountered a 54-metre gross oil column, 13 metres of which were in Upper Jurassic sandstones with very good reservoir quality, and about 30 metres in the Zechstein group’s carbonate rocks with variable reservoir properties. The limestone in the upper section (23 metres) is of poor reservoir quality, while the reservoir quality in the lower, dolomitic section (7 metres) varies from poor to good. The total thickness of the Zechstein group is 67 metres. The reservoir sandstone in Upper Jurassic is thicker and turned out to be somewhat shallower than expected. The pressure data and oil sample indicates communication between the sandstones in the Upper Jurassic and the carbonate rocks in the Zechstein group.
Extensive data acquisition and sampling have been carried out. A formation test was carried out in the Upper Jurassic sand interval. The test yielded a maximum rate of approx. 800 standard cubic metres (Sm3) of oil per flow day through a 52/64-inch nozzle opening. The test showed very good flow properties and indicated no barriers within a radius of 3 to 4 kilometres.
Well 16/3-8 S is the 20th exploration well drilled in production licence 501, which was awarded in APA 2008.
Appraisal well 16/3-8 S was drilled to a vertical depth of 2010 metres below the sea surface and was terminated in the Rotliegendes group in Permian rocks. The well will be permanently plugged and abandoned. The water depth is 116 metres.
The well was drilled by the Bredford Dolphin drilling facility, which is now headed for production licence 484 in the Norwegian Sea to drill wildcat well 6608/10-16, where Noreco Norway AS is the operator.
Contact in the Norwegian Petroleum Directorate
Eldbjørg Vaage Melberg, tel. +47 51 87 61 00