2/4-15 S

General

The primary purpose of well 2/4-15 S was to control and kill the underground blow out in well 2/4-14. Well 2/4-15 S was planned deviated from a location ca 1 km south of the 2/4-14 location to intersect with the 2/4-14 well bore below the bottom hole assembly that had been left in this hole. The well would serve several possible uses:

- Assist in killing 2/4-14 below the BHA.

- To check and verify the extent of underground pressure charging, zone isolation and underground blowouts, and to cure and verify possible cross flows.

- To serve as an emergency relief well to dynamically kill an uncontrolled blow out in well 2/4-14.

- To be used as an exploration well if the top intervention was successful.

Shallow gas was predicted at 611 m where a seismic anomaly corresponds to a gas bearing sand layer in well 2/4-14

Operations and results

Wildcat Relief well 2/4-15 S was spudded 31 January 1989 by the semi-submersible installation Treasure Saga. The well was spudded 1182 m south of the 2/4-14 spud location and drilled to 4962 m where it intersected with the 2/4-14 well bore. This point is recognized as TD of the well. The well was drilled with sea water/gel mud down to 920 m, with KCl mud from 920 m to 3867 m, and with Hi-Temp polymer mud from 3867 m to TD. Shallow gas was encountered at 611 m as prognosed. Thin gas-bearing sands were seen on the resistivity MWD log also at 525 m and at 627 m. Drilling proceeded with significant problems due to rich smectite content between 1800 and 2300 m. The drill string got stuck twice, backed off, and after unsuccessful fishing, technical sidetracks were performed. On 1 May 1989, when drilling the 12 1/4" section in well 2/4-15 S, well 2/4-14 was re-entered with the jack up rig Neddrill Trigon. Both wells were now involved in the killing operations (see well history for 2/4-14 R). When drilling 2/4-15 S at around 4962 m, just prior to pulling