25/1-9
Export: PDF
-
General information
-
Wellbore history
GeneralWell 25/1-9 was drilled nearby and south of the Frigg structure close to the UK boarder, and was designed to prove possible hydrocarbon accumulation in the Frigg Formation and "Cod" sandstone (Intra Balder Formation Sandstone). A main objective was to verify the seismo-stratigraphic interpretation in block 25/1. In addition, the well was expected to obtain valuable data input to the Frigg Field reservoir simulation study. The prognosed depth was 2813 m, 50 m into the Shetland Group.Operations and resultsWildcat well 25/1-9 was spudded with Wi1h. Wi1helmsen installation Treasure Scout 9 September 1996 and drilled to TD at 2807 m in the Late Cretaceous Hardråde Formation. Drilling proceeded without significant problems. The well was drilled with seawater and hi-vis pills down to 990 m, with KCl/polymer mud from 990 m to 1965 m, and with PAC/polymer/seawater from 1965 m to TDThe Frigg Formation was encountered at 2035 m. It consisted of very fine to fine, hard sandstones with poor reservoir characteristics down to 2051 m. From 2051 m to 2199 m the lithology was predominantly massive sandstone with excellent reservoir characteristics. Occasional stringers of claystone and what was interpreted as concretions of calcite-cemented sandstone occurred throughout the section. The lower part, from 2196 m to 2237 m was claystone with a3 m conglomerate at the base.Hydrocarbons were encountered in the Frigg Formation with 2.6 m net pay of gas down to 2054 m and 6.9 m net pay oil down to a free water level at 2063 m. RFT pressure measurements gave an oil gradient corresponding to a fluid density of 0.81 g/cm3. Pore pressure indicated pressure depletion due to production from the Frigg Field. RFT data indicated that the Frigg Formation contains small reserves and the discovery was considered uneconomic.The gas/oil contact was defined at 2054 m, and the oil/water contact at 2063 m. Only very weak shows were recorded in the underlying water zone and Intra Balder Formation Sandstone. Two segregated fluid samples were taken, one in the gas zone and one in the oil zone. Four cores were cut in the interval 2048 - 2111 m, and one core was cut in the interval 2234 - 2256 m. The Frigg Formation came in at 2035 m as prognosed. The well was permanently abandoned as an oil and gas discovery 12 October 1986.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]1000.002807.00 -
Cores at the Norwegian Offshore Directorate
Cores at the Norwegian Offshore Directorate Core sample numberCore sample - top depthCore sample - bottom depthCore sample depth - uom12048.02049.2[m ]22049.52068.0[m ]32068.02087.2[m ]42088.52107.0[m ]52234.02255.0[m ]Cores at the Norwegian Offshore Directorate Total core sample length [m]78.4Cores at the Norwegian Offshore Directorate Cores available for sampling?YES -
Core photos
-
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 typeCONDUCTOR30221.036221.00.00LOTSURF.COND.20974.026990.01.33LOTINTERM.13 3/81947.017 1/21965.01.74LOTOPEN HOLE2807.012 1/42807.00.00LOT -
Logs
Logs Log typeLog top depth [m]Log bottom depth [m]CBL VDL8651947CST19682764CST19682347DIL LSS GR SP9751915DIL LSS GR SP19472776DIL LSS SP GR19472749DLL MSFL NSG SP GR20252300LDL CNL GR CAL19472756LDL GR CAL9751915MWD - GR RES DIR1352807NGS20252300RFT20522056RFT20522736RFT20542547SHDT19472757VSP10002780 -
Lithostratigraphy
Lithostratigraphy Top depth [mMD RKB]Lithostrat. unit135367990203522372237233223732402242024522480251525502603265526682675269727572757 -
Composite logs
Composite logs Document nameDocument formatDocument size [MB]pdf0.36 -
Geochemical information
Geochemical information Document nameDocument formatDocument size [MB]pdf0.51 -
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]pdf13.25 -
Drilling mud
Drilling mud Depth MD [m]Mud weight [g/cm3]Visc. [mPa.s]Yield point [Pa]Mud typeDate measured1701.03WATER14.10.19862211.15WATER09.09.19864531.15WATER10.09.19866211.03WATER14.09.19869900.00WATER14.09.19869900.0014.07.0WATER15.09.19869901.15WATER11.09.198610341.1310.07.0WATER16.09.198613001.1514.011.0WATER17.09.198617151.1613.010.0WATER18.09.198617971.0916.09.0WATER09.10.198619401.1612.010.0WATER21.09.198619651.2014.08.0WATER21.09.198619650.0014.010.0WATER21.09.198619650.0014.010.0WATER22.09.198619741.0810.09.0WATER23.09.198620501.0813.010.0WATER24.09.198620891.0815.08.0WATER25.09.198621111.0814.09.0WATER28.09.198622341.0817.013.0WATER28.09.198622441.0818.013.0WATER28.09.198623191.0818.012.0WATER29.09.198625111.0818.014.0WATER30.09.198626021.0918.014.0WATER01.10.198627021.0918.012.0WATER02.10.198627231.0917.011.0WATER05.10.198628071.0819.013.0WATER05.10.198628070.0019.012.0WATER05.10.198628070.0016.011.0WATER07.10.198628070.0015.011.0WATER08.10.198628070.0016.012.0WATER06.10.1986 -
Palynological slides at the Norwegian Offshore Directorate
Palynological slides at the Norwegian Offshore Directorate Sample depthDepth unitSample typeLaboratory2055.0[m]CR.R.I2076.0[m]CR.R.I2090.0[m]CR.R.I2200.0[m]SWCR.R.I2216.0[m]SWCR.R.I2232.0[m]SWCR.R.I2235.0[m]CR.R.I2240.0[m]CR.R.I2253.0[m]CR.R.I2254.0[m]CR.R.I2261.0[m]SWCR.R.I2287.0[m]SWCR.R.I2334.0[m]SWCR.R.I2340.5[m]SWCR.R.I2347.0[m]SWCR.R.I2369.5[m]SWCR.R.I2377.0[m]SWCR.R.I2385.0[m]SWCR.R.I2393.5[m]SWCR.R.I2407.5[m]SWCR.R.I2416.0[m]SWCR.R.I2427.0[m]SWCR.R.I2443.0[m]SWCR.R.I