Well 6406/12-4 S was drilled approximately 33 km southwest of the Njord field in the southern part of the Norwegian Sea and approx. 1.7 km southeast of discovery well 6406/12-3 S (Pil).
The primary exploration target of well 6406/12-4 S was to prove petroleum in Upper Jurassic sandstones in a southwestern segment, which is adjacent to the 6406/12-3 S discovery (Pil). The well encountered an approximately 590 m thick unit of Upper Jurassic rocks, 20 m of which of are sandstone (the Rogn formation) with good reservoir quality. Preliminary estimates of the size of the discovery range between two and five million standard cubic metres (Sm3) of recoverable oil equivalents. The licensees will consider the discovery in conjunction with other nearby discoveries as regards a possible future development.
The secondary exploration target was to prove petroleum in Upper Jurassic rocks (sandstone in the Intra Melke formation), the extent, thickness and properties of the reservoir rocks, as well as depth to hydrocarbon contacts. The well encountered 368 m of sandstone in the Intra Melke formation of varying quality and with traces of oil.
The objective of well 6406/12-4 A was to prove petroleum in Upper Jurassic reservoir rocks (sandstone in the Intra Spekk and Intra Melke formations) in a southern segment adjacent to the 6406/12-3 S discovery (Pil). Well 6406/12-4 A encountered about 20 m of Intra Spekk sandstone and 515 m of reservoir rocks in the Intra Melke formation, both with poor reservoir properties. The reservoir contains only traces of hydrocarbons. The well was classified as dry.
Extensive data acquisition and sampling have been carried out. These are the fourth and fifth wells to be drilled in production licence 586, which was awarded in APA 2010.
6406/12-4 S was drilled to measured and vertical depths of 4318 and 3832 m below sea level respectively, and was terminated in the Melke formation in the Upper Jurassic.
6406/12-4 A was drilled to measured and vertical depths of 4058 and 3799 m below sea level respectively, and was terminated in the Melke formation in the Jurassic. Water depth at the site is 319 m.
The wells will now be permanently plugged and abandoned.
Wells 6406/12-4 S and A were drilled by the drilling facility Transocean Arctic which now will drill 6406/12-5 S in a northern segment adjacent to the discovery 6406/12-3 S (Pil).
Adapted from a press release by Louise Mulhall