1/3-11 is a wildcat exploration wellbore in the North Sea, drilled by DONG E&P Norge AS, entered May 28, 2008, to 3,595 m in the Ekofisk Fm.
Discovery 1/3-11 (Ipswich) · On the map →
- 3,595
- m total depth · 3,507 m vertical
- 72
- m water depth
- May 28, 2008
- entered · completed Aug 30, 2008
- Ekofisk Fm
- at total depth · Paleocene
- 93.7
- m of core in 5 cores
- 140
- °C bottom-hole temperature
SODIR FACTPAGES · RECORD UPDATED FEB 20, 2026 · RELEASED AUG 30, 2010
On file for this wellbore
What the Directorate holds from this wellbore. Each opens the section that lists it.
Drilling
- Drilling facility
- MÆRSK GUARDIAN · Jack-up 3 legs
- Drilling days
- 95
- Kelly bushing elevation
- 42 m
- Maximum inclination
- 20.29999924°
- Drilling permit
- 1179-L
- Licensing round
- NST2001
- Plugged and abandoned
- —
- Core samples available
- Yes
- Cuttings samples available
- Yes
- Position · ED50
- 56.84958° N, 2.72095° E
- Hydrocarbons in
- Forties Fm · Paleocene
Well history
WRITTEN BY THE NORWEGIAN OFFSHORE DIRECTORATE
General
The 1/3-11 Ipswich well was drilled in the Central Graben of the North Sea about 9 km south of the 1/3-10 Oselvar well, which confirmed oil in a similar geological setting to that of the Ipswich prospect. The primary objective of the 1/3-11 well was to determine the presence and nature of recoverable hydrocarbons in the Forties Formation Sandstone reservoir expected to exist along the western flank of the Ipswich salt dome.
Operations and results
Wildcat well 1/3-11 was spudded with the jack-up installation Mærsk Galant on 28 May 2008 and drilled to 3289 m in the Paleocene Våle Formation. The well path was drilled with a slight S shape after the originally planned surface location was moved to avoid potential shallow gas. Due to unexpected lithology the original hole penetrated most of an hydrocarbon-bearing reservoir sand in the well without cores being taken. Therefore it was decided to make a technical coring side-track, in which also fluid samples would be obtained. The sidetrack was denoted technical (1/3-11 T2) as coring was the main objective. It was kicked off at 1330 m and drilled to final TD at 3595 m in the Paleocene Ekofisk Formation. The well was drilled with seawater and pre-hydrated bentonite down to 825 m, with KCl/polymer mud from 825 m to 1306 m, and with Carbo SEA oil based mud from 1306 m to TD, including the technical sidetrack.
The well penetrated the clays and claystones (with sand interbeds) of the Nordland Group, the claystones of the Hordaland Group, and the claystones, tuffaceous claystones and sandstones of the Rogaland Group. The latter contained the Balder Formation, the Sele Formation (which was expected to contain the target Forties Formation sandstone), the Lista Formation and the Vål
Around this wellbore
This wellbore on Sodir FactPages → · Press release →
About this data
Norwegian Offshore Directorate (Sodir) FactPages, mirrored nightly and used under the Norwegian Licence for Open Government Data (NLOD). Depths are metres along the wellbore from the kelly bushing unless a row gives its own unit; older cores are filed in feet. A zero the Directorate files for an unmeasured pressure, density, or temperature is shown as a dash.
Developers: this page as JSON is GET /v1/data/norway/wells/5806, documented in the API reference.