36/7-2

General

Well 36/7-2 was drilled on the Øygarden Fault Complex, ca 14 km west of the outer skerries of Bulandet in Sogn og Fjordane county. The primary target were the Late Jurassic Sognefjord and the Upper Jurassic Fensfjord formations.

Operations and results

Wildcat well 36/7-2 was spudded with the semi-submersible installation West Vanguard on 2 September 1997 and drilled to TD at 1435 m in basement rock. An anchor test was performed after setting the 13 3/8" casing shoe. Anchor no. 2 and 3 failed the test to 180 ton and slipped at 170 ton. Piggyback anchors were set on anchor no. 2, while main anchor no. 3 was lost. Fishing for the anchor chain was delayed 47.5 hrs due to bad weather. The anchor chain was retrieved and the anchor reset with two piggy backs. Both anchors then stood a successful test. The well was drilled with seawater and hi-vis pills down to 591 m and with ANCO 2000 from 591 m to TD.

The well discovered heavily biodegraded oil in the Middle Jurassic deltaic sandstone reservoir of the Fensfjord Formation. The overlying Sognefjord Formation sands were tight and contained no hydrocarbons. A 32.5 m oil column was proven from 931.5 to ca 964.0 m. The exact level of the oil-water contact could not be determined as it was in a shaley zone. Oil shows on cuttings were recorded from 915 m down to 1045 m. The reservoir zone of the Fensfjord Formation was divided into two units, from which only the upper had good reservoir properties.

No conventional cores were cut, but 60 sidewall cores were taken from 603 to 1408 m with a recovery of 56 samples. The MDT tool was run and 23 good pressure points were acquired in addition to a fluid sample at 934.5 m.

The well was completed on 22 September 1997 as an oil discovery.

Testing

No drill stem test was performed.