Alvheim set for further tiebacks

Marathon Petroleum has discovered more oil in the Alvheim area of the Norwegian North Sea.

Offshore staff

OSLO, Norway -- Marathon Petroleum has discovered more oil in the Alvheim area of the Norwegian North Sea.

Although the oil volumes are relatively modest, they likely will be tied into a new subsea development linked to the Alvheim facilities, according to partner Lundin Petroleum.

The semisub Transocean Winner drilled the discovery well 24/9-10 S, and the subsequent sidetrack/appraisal well 24/9-10 A, 1.5 km (0.9 mi) to the northwest, at a location 31 km (19 mi) south of the Alvheim FPSO.

Lundin says the main aim was to prove oil in upper Palaeocene reservoir rocks (Hermod formation). This was achieved. Both wells encountered oil in 26-m and 24-m (85- and 79-ft) columns in a sandstone reservoir. Preliminary estimates put Caterpillar in the range 5-12 MMboe.

Development studies are progressing for last fall’s Bøyla (ex-Marihøne), 8 km (4.9 mi) northwest of Caterpillar, and the two fields will probably tieback jointly to the Alvheim production ship.

These are the first wells drilled on the PL 340 S concession, which was awarded a year ago under Norway’s APA 2009 licensing round. They were drilled in a water depth of 117 m (384 ft), and have since been permanently plugged and abandoned

TheTransocean Winner now heads to PL505 to drill the Earb South prospect (well 25/10-11) for Marathon.

2/15/2011

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