ID: 291
OBJECTID: 291
wlbNpdidWellbore: 296
wlbName: 7/12-3
wlbHistory:

General

Well 7/12-3 was drilled as an appraisal well on the western flank of the 7/12-2 Ula Discovery in the North Sea.

Operations and results

Appraisal well 7/12-3 was spudded with the semi-submersible installation Norskald on 5 April 1977 and drilled to TD at 3710 m in Late Jurassic sediments. The drilling, coring and logging of the well were of a routine nature. Plugging of the flow lines and screens by hydrating clays while drilling the 17-1/2" hole caused delays and the loss of considerable quantities of mud. Rates of penetration were less than anticipated in the Lower Cretaceous and Upper Jurassic mudstones/ shales. Ninety-four hours were lost through weather delays during the course of the well. The well was drilled with fresh water and gel down to 471 m and with Lime/Drispac mud from 471 m to TD.

Core, log and R.F.T. analyses proved the well to have penetrated the Jurassic reservoir discovered in well 7/12-2 beneath the oil water contact.

One core was cut in the Jurassic section, from 3612.2 to 3628.6 m. An RFT water sample was taken at 3683 m

The well was plugged back for sidetracking on 3 June as a dry well.

Testing

No drill stem test was performed.

wlbHistoryDateUpdated: 2016-07-06T00:00:00