34/4-6
Export: PDF
-
General information
-
Wellbore history
GeneralWell 34/4-6 was drilled in the northern part of the Snorre Field. The main objectives were to test the northern outline of the field and to confirm the oil/water-contact and reservoir characteristics of the Upper Lunde Formation. The stratigraphy and reservoir characteristics of the Middle and Lower Lunde together with the Lomvi Formations were secondary objectives. Prognosed depth was at 3236 m in Triassic rocks.Operations and resultsAppraisal well 34/4-6 was spudded with the semi-submersible installation Vinni on 31 December 1995 and drilled to TD at 3282 m in the Late Triassic Teist Formation. The 26" section was hampered by bad weather and large parts of the period from the evening of 9 January up to 18 January was spent as WOW. When reaching 740 m the bad weather also made it necessary to disconnect the riser from the well head. Technical problems when attempting to re-latch the pin connector back on to the well head resulted in the remaining section down to TD at 920 m in the 26" section being drilled with no returns to the surface. The well was drilled with spud mud down to 530 m, with gel mud from 530 m to 920 m, with gypsum/polymer mud from 920 m to 2345 m, and with gel mud from 2345 m to TD.Apart from the sandy Utsira Formation of Late - Middle Miocene to Pliocene age (1127.5 - 1239 m) and a sandstone unit within the Hordaland Group of Early Oligocene age (1358.5 - 1387 m), the upper section down to the Base Cretaceous Unconformity proved mainly claystones. No Jurassic rocks were encountered in the well. The Triassic Hegre Group consists of sandstones with minor shales and siltstones down to TD of the well. The target horizon, the Upper Lunde Formation, was encountered at 2576.5 m, 65 m deeper than prognosed. It had a gross thickness of 68.5 m with 39.7 m net sand. Hydrocarbons were encountered in the uppermost part of this formation with an OWC was at 2587 m, determined from RFT pressure points.The first appearance of shows was seen in the Shetland Group from ca 2090 m. This was seen in silt lenses where pale yellow fluorescence was accompanied by slow to moderate streaming blue white cut reaction. A slight yellow residue was occasionally observed. Entering the main reservoir at 2576.5 m, the shows were as follows in the interval 2576.5 - 2587 m (OWC): 100% yellow brown oil stain, 100% yellow fluorescence with instant to fast streaming blue white cut, leaving a light yellow brown residue upon evaporation. The odour was good. Below the OWC, shows decreased gradually to become extinct below 2624 m.Six cores were cut totalling 84.5 m. One core was cut in the Shetland Group crossing the border zone into Cromer Knoll Group. The other cores were taken in the Late Lunde Group where hydrocarbons were encountered in the uppermost section. The RFT chambers from this well gave no pressurized fluid samples. An atmospheric RFT sample from 2580 m contained ca 1.6 l oil and ca 2 l water/mud filtrate.The well was permanently abandoned on 27 March 1986 as an oil appraisal.TestingOne DST test was performed in the well. This was a combined production/interference test in the Upper Lunde Formation. The well produced from the interval 2577 - 2585 m, with the interval 2592 - 2595 m as an observation interval. The test included three flow periods; 1) Clean-up flow of the lower zone; 2) initial flow of the upper zone; 3) main flow of the upper zone. The two first flows produced only cushion water. The last flow produced 1206 Sm2 oil /day with a wellhead pressure of 153.6 bar. The flowing bottom hole pressure was 359.6 bar at 2546.9 m. The gas-oil ratio was measured to 91.3 Sm3 /Sm3 after a four stage separation. The corresponding dead oil density was 824.5 kg/Sm3. Maximum temperature in the test was 99.7 deg C. During flow 3) wellhead samples and samples for recombination from the separator were taken. These samples include the "DST3" samples in the geochemical download report from IKU found further down on this fact page. -
Cuttings at the Norwegian Offshore Directorate
Cuttings at the Norwegian Offshore Directorate Cuttings available for sampling?NOCuttings at the Norwegian Offshore Directorate Cutting sample, top depth [m]Cutting samples, bottom depth [m]530.003207.00 -
Cores at the Norwegian Offshore Directorate
Cores at the Norwegian Offshore Directorate Core sample numberCore sample - top depthCore sample - bottom depthCore sample depth - uom12549.52553.3[m ]22576.02583.0[m ]32589.02596.5[m ]42600.02612.9[m ]52614.02622.4[m ]62642.02660.5[m ]Cores at the Norwegian Offshore Directorate Total core sample length [m]58.1Cores at the Norwegian Offshore Directorate Cores available for sampling?YES -
Core photos
-
Oil samples at the Norwegian Offshore Directorate
Oil samples at the Norwegian Offshore Directorate Test typeBottle numberTop depth
MD [m]Bottom depth
MD [m]Fluid typeTest timeSamples availableDSTDST10.000.00OIL18.03.1986 - 00:00YES -
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 typeCONDUCTOR30521.036530.00.00LOTSURF.COND.20904.026920.01.63LOTINTERM.13 3/81841.017 1/21856.01.80LOTINTERM.9 5/82760.012 1/42770.01.99LOT -
Drill stem tests (DST)
Drill stem tests (DST) Test numberFrom depth MD
[m]To depth MD
[m]Choke size
[mm]1.0259225956.41.12577258512.7Drill stem tests (DST) Test numberFinal shut-in pressure
[MPa]Final flow pressure
[MPa]Bottom hole pressure
[MPa]Downhole temperature
[°C]1.0931.193Drill stem tests (DST) Test numberOil
[Sm3/day]Gas
[Sm3/day]Oil density
[g/cm3]Gas grav. rel.airGOR
[m3/m3]1.01.11173727260.8210.77062 -
Logs
Logs Log typeLog top depth [m]Log bottom depth [m]CBL VDL GR7501841CBL VDL GR27803255CST18532762CST18532762DLL MSFL GR SP25452766GR0530ISF DDBHC GR521917ISF DDBHC GR9041853ISF LSS GR18412769ISF LSS GR27613281LDL CNL GR27613282LDL CNL NGT GR18412769LDL GR521919LDL GR9041854MWD521919MWD9041854MWD18412770MWD27613282RFT25782747RFT25802580RFT25832585SHDT GR18412770SHDT GR27613282VELOCITY3003240 -
Lithostratigraphy
Lithostratigraphy Top depth [mMD RKB]Lithostrat. unit40012101250135913871658165816881775177520562555255525652577257731533231 -
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]pdf1.65pdf8.39 -
Drilling mud
Drilling mud Depth MD [m]Mud weight [g/cm3]Visc. [mPa.s]Yield point [Pa]Mud typeDate measured5301.06WATER BASED03.01.19865301.06WATER BASED06.01.19865301.06WATER BASED30.12.19855851.077.016.3WATER BASED13.01.19867401.146.013.5WATER BASED13.01.19869041.1012.07.2WATER BASED05.02.19869201.1012.07.2WATER BASED05.02.19869201.127.013.9WATER BASED13.01.19869201.146.012.5WATER BASED13.01.19869201.127.014.4WATER BASED13.01.19869201.145.09.6WATER BASED14.01.19869201.155.010.1WATER BASED13.01.19869201.155.010.6WATER BASED13.01.19869201.146.011.1WATER BASED19.01.19869201.148.011.5WATER BASED19.01.19869201.149.010.6WATER BASED19.01.19869201.03WATER BASED19.01.19869201.145.012.0WATER BASED13.01.19869201.155.010.1WATER BASED19.01.198611101.1119.010.1WATER BASED05.02.198613811.1317.09.1WATER BASED05.02.198617911.3120.010.6WATER BASED05.02.198618561.4822.08.7WATER BASED05.02.198618561.4824.09.1WATER BASED05.02.198618561.4825.09.6WATER BASED05.02.198618561.4825.010.6WATER BASED05.02.198618611.4817.09.6WATER BASED05.02.198621271.5519.011.5WATER BASED05.02.198622731.6527.012.0WATER BASED05.02.198623451.6521.011.1WATER BASED11.02.198624431.6821.010.1WATER BASED11.02.198624951.6816.08.7WATER BASED11.02.198624981.6818.09.6WATER BASED11.02.198625491.7019.06.8WATER BASED11.02.198625601.7019.06.3WATER BASED11.02.198625751.7022.06.3WATER BASED12.02.198625751.7023.07.2WATER BASED17.02.198625761.7022.06.8WATER BASED11.02.198625761.7018.06.8WATER BASED10.03.198625761.7018.06.8WATER BASED17.03.198625761.7019.06.8WATER BASED17.03.198625761.7017.06.3WATER BASED24.03.198625761.7019.06.8WATER BASED24.03.198625761.7019.07.2WATER BASED24.03.198625761.7017.06.3WATER BASED18.03.198625761.7018.06.8WATER BASED24.03.198625881.7022.06.3WATER BASED12.02.198626001.7023.06.8WATER BASED12.02.198626321.7022.06.8WATER BASED17.02.198626601.7022.07.7WATER BASED17.02.198626801.7017.07.7WATER BASED10.03.198627001.7018.06.8WATER BASED10.03.198627201.7018.06.3WATER BASED12.03.198627201.7018.06.3WATER BASED08.03.198627201.7018.06.3WATER BASED17.03.198627461.7020.07.7WATER BASED17.02.198627601.6217.06.8WATER BASED05.03.198627601.6221.07.2WATER BASED28.02.198627601.6217.07.7WATER BASED03.03.198627601.6218.06.8WATER BASED03.03.198627601.6219.07.7WATER BASED04.03.198627701.6243.08.2WATER BASED26.02.198627701.7022.07.7WATER BASED24.02.198627701.7027.07.7WATER BASED24.02.198627701.7020.07.7WATER BASED24.02.198627701.7022.07.7WATER BASED24.02.198627701.6226.06.8WATER BASED26.02.198627921.6219.06.8WATER BASED28.02.198632821.6217.06.8WATER BASED10.03.198632821.7018.07.2WATER BASED10.03.1986 -
Palynological slides at the Norwegian Offshore Directorate
Palynological slides at the Norwegian Offshore Directorate Sample depthDepth unitSample typeLaboratory1853.0[m]SWCR.R.I1875.0[m]SWCR.R.I1900.0[m]SWCR.R.I1925.0[m]SWCR.R.I1960.0[m]SWCR.R.I2001.0[m]SWCR.R.I2025.0[m]SWCR.R.I2068.0[m]SWCR.R.I2130.0[m]SWCR.R.I2225.0[m]SWCR.R.I2267.0[m]SWCR.R.I2300.0[m]SWCR.R.I