2/3-2

General

Well 2/3-2 is located on the Sørvestlandet High north of the Søgne Basin and south of the Åsta Graben. The well was drilled to determine if Oligocene - Miocene reservoirs were developed off the flanks of the 2/3-1 structure and if the hydrocarbon accumulations tested in the 2/3-1 well extended beyond the spill point of the structure. Total depth of the well was planned in Lower Oligocene.

The well is Reference Well for the Vade Formation.

Operations and results

Appraisal well 2/3-2 was spudded with the semi-submersible installation Ocean Traveller on 26 July 1969 and drilled to TD at 2297 m in Paleocene sediments. The water depth at the location is 58 m. The surface hole was drilled to 299 m, to simulataneously run the 30 inch and 20 inch casings. Problems with stuck pipe occurred. High pump pressure and difficulty in washing past 265 m required pulling out of the hole again. It was found that two drill collars and the bit had backed off. A dive was made to determine if the fish was on the ocean floor. It could not be found. The hole was abandoned and repositioned 20 m due east of the original location, for re-spudding. After this no significant problems occurred during drilling. The 36" and 26" holes, down to 211 m were drilled with sea water and returns were to the sea floor. The rest of the well was drilled with a Q-Broxin/Caustic type mud. As in well 2/3-1 bridging caused problema during the logging operations. This was especially evident in the 17 1/2 inch hole, which had to be reamed and circulated. Still it turned out to be impossible to obtain an open hole GR/BHC-Sonic survey.

At 1795 m a sandy sequence, the Vade Formation, was encountered. It was described as two sandstone beds, greenish gray, very fine grained, poorly consolidated, porous and permeable. The sandstone beds were separated by about 15 m of dark brown shale with thin streaks of dolomitic limestone. Below the Vade sand only thin sand beds coul