31/6-2
Export: PDF
-
General information
-
Wellbore history
GeneralAppraisal well 31/6-2 was drilled on a location on the south-east periphery on the Troll East gas province. The main objective was to test the gas and oil accumulations in sandstones of Late to Middle Jurassic age. The planned TD was about 200 m into rocks of Triassic age to an estimated total depth of 2400 m RKB.The well is Reference well for the Hardråde Formation and for the undifferentiated Shetland Group in the Troll area.Operations and resultsWell 31/6-2 was spudded with the semi-submersible installation Deepsea Bergen on 18 October 1983 and drilled to TD at 2020 m in the Early Jurassic Drake Formation. Because of problems with a leak in 20" casing and lost circulation problems in a major fault, both 13 3/8" and 9 5/8" casing had to be set high. The well was drilled with sea water and hi-vis pills down to 412 m, with AQUAGEL/seawater spud mud from 412 m to 801 m, with KCl polymer mud from 801 m to TD. At 984 m Lost Circulation Material -pills were added to cure lost circulation problems.No reservoir sections were developed above the Jurassic. The well encountered 113 m of Draupne shale with top at 1322 m, overlying a 25 m thick Heather Formation sequence. The Sognefjord Formation sandstone reservoir was encountered at 1460 m with a gas column of approximately 110 m. No oil leg could be detected from electric logs or FMT's. Oil shows were recorded on sidewall core sandstone in the interval from 1831 m to 1988 m in the Middle to Early Jurassic. Nine cores were cut from 1435 m to 1619 m in the Heather and Sognefjord Formations. FMT sampling in the Sognefjord Formation recovered small amounts of gas from 1475 m and 1572 m. A sample from 1577 m gave mud filtrate.The well was suspended on 11 December 1983 as a gas appraisal.TestingNo drill stem test was performed. -
Cuttings at the Norwegian Offshore Directorate
Cuttings at the Norwegian Offshore Directorate Cuttings available for sampling?YESCuttings at the Norwegian Offshore Directorate Cutting sample, top depth [m]Cutting samples, bottom depth [m]420.002235.00 -
Cores at the Norwegian Offshore Directorate
Cores at the Norwegian Offshore Directorate Core sample numberCore sample - top depthCore sample - bottom depthCore sample depth - uom11435.01453.3[m ]21453.01471.4[m ]31471.61483.6[m ]41483.61497.1[m ]51497.11515.9[m ]61515.71543.4[m ]71543.61571.5[m ]81571.51589.0[m ]91591.01618.3[m ]Cores at the Norwegian Offshore Directorate Total core sample length [m]181.4Cores at the Norwegian Offshore Directorate Cores available for sampling?YES -
Core photos
-
Palynological slides at the Norwegian Offshore Directorate
Palynological slides at the Norwegian Offshore Directorate Sample depthDepth unitSample typeLaboratory995.0[m]SWCIKU1050.0[m]SWCIKU1250.0[m]SWCIKU1294.0[m]SWCIKU1326.5[m]SWCIKU1344.5[m]SWCIKU1360.0[m]SWCIKU1380.0[m]SWCIKU1399.0[m]SWCIKU1411.0[m]SWCIKU1426.0[m]SWCIKU1630.0[m]SWCIKU1660.0[m]SWCIKU1686.0[m]SWCIKU1710.0[m]SWCIKU1726.0[m]SWCIKU1745.0[m]SWCIKU1783.0[m]SWCIKU1800.0[m]SWCIKU1831.0[m]SWCIKU1855.0[m]SWCIKU1902.0[m]SWCIKU1915.5[m]SWCIKU1927.0[m]SWCIKU1937.0[m]SWCIKU1988.5[m]SWCIKU -
Lithostratigraphy
Lithostratigraphy Top depth [mMD RKB]Lithostrat. unit32650562662677688596896897811281128122313221322143514601625164218751910193119751975 -
Geochemical information
-
Documents – reported by the production licence (period for duty of secrecy expired)
Documents – reported by the production licence (period for duty of secrecy expired) Document nameDocument formatDocument size [MB]pdf18.98pdf1.29pdf7.28pdf0.88pdf0.46pdf0.66pdf13.96pdf6.31pdf6.12pdf2.46pdf0.85pdf2.60pdf9.45pdf0.17pdf25.98pdf5.83pdf8.92pdf5.38pdf6.17pdf6.40pdf3.19pdf3.03pdf17.60pdf2.77pdf6.41pdf1.07 -
Logs
Logs Log typeLog top depth [m]Log bottom depth [m]ACBL VDL GR326902ACBL VDL GR5151390CDL CNL GR CAL8002020CDL GR CAL412816DIFL BHC AC GR SP4122020DLL MLL GR13902020FMT13902020HR DIP9031400HR DIP13902020SPECTRALOG13902020VSP8952020 -
Casing and leak–off tests
Casing and leak–off tests Casing typeCasing diam.
[inch]Casing depth
[m]Hole diam.
[inch]Hole depth
[m]LOT/FIT mud eqv.
[g/cm3]Formation test typeCONDUCTOR30412.036412.00.00LOTSURF.COND.20801.026818.01.56LOTINTERM.13 3/8902.017 1/2920.01.76LOTINTERM.9 5/81391.012 1/41400.01.61LOTLINER72004.08 1/22020.00.00LOT -
Drilling mud
Drilling mud Depth MD [m]Mud weight [g/cm3]Visc. [mPa.s]Yield point [Pa]Mud typeDate measured4101.0445.0WATER BASED4801.0841.0WATER BASED9001.3047.0WATER BASED10101.2044.0WATER BASED14701.2546.0WATER BASED20051.1052.04.8WATER BASED07.08.198420751.1063.06.2WATER BASED07.08.198422351.1156.05.8WATER BASED07.08.198422351.1157.04.8WATER BASED07.08.1984 -
Pressure plots
Pressure plots The pore pressure data is sourced from well logs if no other source is specified. In some wells where pore pressure logs do not exist, information from Drill stem tests and kicks have been used. The data has been reported to the NPD, and further processed and quality controlled by IHS Markit.Pressure plots Document nameDocument formatDocument size [MB]pdf0.16