General information Attribute Value Wellbore nameOfficial name of wellbore based on NPD guidelines for designation of wells and wellbores.35/11-2 TypeWellbore type. Legal values: EXPLORATION, DEVELOPMENT, OTHER (see 'Purpose' for more information)EXPLORATION PurposeFinal classification of the wellbore.
Legal values for exploration wellbores:
WILDCAT, APPRAISAL, WILDCAT-CCS, APPRAISAL-CCS.
Legal values for development wellbores:
OBSERVATION, PRODUCTION, INJECTION, INJECTION-CCS, OBSERVATION-CCS.
Legal values for other wellbores:
SOIL DRILLING (drilling in connection with track surveys and other subsurface surveys to investigate the soil conditions prior to placement of facilities),
SHALLOW GAS (drilling to investigate shallow gas before the first 'real' drilling on the location),
PILOT (drilling to investigate the geology and fluid connectors for location of the main wellbore),
SCIENTIFIC (drilling according to Law of Scientific research and exploration),
STRATIGRAPHIC (driling according to Law of Petroleum activities §2-1).WILDCAT
StatusStatus for the wellbore. Legal values are:
BLOWOUT: A blowout has occurred in the well.
CLOSED: A development wellbore that has been closed in a shorter or longer periode. Also applies to development wellbores where drilling is completed, but production/injection has not yet been reported.
DRILLING: The well is in the drilling phase - can be active drilling, logging, testing or plugging,
JUNKED: The drilling operation has been terminated due to technical problems.
P&A: Exploration: The well is plugged and abandoned, and can not be reentered for further use. Development wells: The production/injection from/to the well is stopped and the well is plugged. The wellhead is removed or else made unavailable for further well operations.
PLUGGED: The wellbore has been plugged, but the upper parts of the wellbore can be re-used. A sidetrack might be drilled at a later stage.
PRODUCING: It was produced from the wellbore at the time of the operators last monthly report to the NPD.
INJECTING: It was injected to the wellbore at the time of the operators last monthly report to the NPD.
PREDRILLED: The upper part of the well has been drilled, usually as part of a batch-drilling campaign covering several wellbores.
RE-CLASS TO DEV: Exploration wellbore that is reclassified to a development wellbore.
RE-CLASS TO TEST: Exploration wellbore that is reclassified to test production.
SUSPENDED: The drilling operation in the wellbore has been temporarily stopped. The current plan is to continue drilling later on.
P&AFactmaps in new window
Main areaName of the area on the Norwegian Continental Shelf where the wellbore is located. Legal values: BARENTS SEA, NORWEGIAN SEA, NORTH SEA.NORTH SEA FieldName of the field the wellbore is related to. DiscoveryName of the discovery the wellbore is related to. Well nameOfficial name of the parent well for the wellbore based on NPD guidelines for designation of wells and wellbores.35/11-2 Seismic locationPosition of spud location on seismic survey lines. SP: shotpoint.NM84 - 208 SP. 520 Production licenceOfficial designation of the production licence the wellbore was drilled or planned to be drilled from ( well head posistion). Drilling operatorName of the licensee starting the drilling operation on behalf of the active production license (well head position). This will usually equal the operator of the production license.Mobil Exploration Norway INC Drill permitThe drilling permit number together with the version of the drilling permit as stated in the drilling permit granted by the NPD.553-L Drilling facilityNPD's name of the facility which the wellbore was drilled from. Drilling daysNumber of days from wellbore entry to wellbore completion.138 Entered dateThe date when he wellbore was spudded. For sidetracks: The date when new formation was drilled by kicking off from the mother-wellbore,20.07.1987 Completed dateExploration wellbores from moveable facilities:
For floating facilities - date when anchor handling is started. For jackups - date the jacking-down started. Exploration wellbores from fixed facilities and all development wellbores:
Date when the wellbore is at total depth, and last casing, liner or screen is set. In case of immediate plugging of the wellbore, completed date equals the date the last plug i set in the wellbore.
Date when the wellbore is at total depth, and last casing, liner or screen is set. In case of immediate plugging of the wellbore, completed date equals the date the last plug i set in the wellbore.
Release dateDate when raw data which has been reported to the authorities from the wellbore is not confidential any longer. Normally 2 years after finishing the drilling. May be earlier if the area of the production license is relinquished.04.12.1989 Publication dateDate quality control of the wellbore information was completed, so it can be published on the internet as a 'Well Data Summary Sheet' wellbore with more information available than other wellbores.25.04.2005 Purpose - plannedPre-drill purpose of the wellbore. Legal values for exploration wellbores: WILDCAT, APPRAISAL, WILDCAT-CCS, APPRAISAL-CCS. Example of legal values for development wellbores: OBSERVATION, PRODUCTION, INJECTION.WILDCAT ReentryStatus whether the wellbore has been re-entered (YES) or not (NO). Re-entered wellbores are not included in the count when wellbores are presented in statistical overviews.NO ContentFor exploration wellbores, status of discovery.
DRY, SHOWS (trace amounts of hydrocarbons), GAS, GAS/CONDENSATE, OIL or OIL/GAS.
SHOWS (GAS SHOWS, OIL SHOWS or OIL/GAS SHOWS) are detected as fluorescent cut (organic extract), petroleum odour, or visual stain on cuttings or cores, or as increased gas reading on the mud-loggers gas detection equipment.
Legal values for WILDCAT-CCS and APPRAISAL-CCS: WATER
For development wellbores, type of produced/injected fluid.
WATER, CUTTINGS, NOT AVAILABLE, OIL, GAS/CONDENSATE, OIL/GAS, CO2, GAS, WATER/GAS, NOT APPLICABLE.GAS/CONDENSATE
Discovery wellboreIndicator which tells if the wellbore made a new discovery. Legal values: YES, NO. Prior to press-release or other information regarding drilling results, the indicator will be “NO” as a default.YES 1st level with HC, ageAge of lithostratigraphic unit, 1st level, where hydrocarbons were encountered. Examples of legal values: CRETACEOUS, EARLY CRETACEOUS, LATE JURASSIC, EOCENE. See also NPD bulletins.MIDDLE JURASSIC 1st level with HC, formationName of lithostartigraphic unit, 1st level, where hydrocarbons were encountered. Shown only for released wells. Examples of legal values: BASEMENT, COOK FM, EKOFISK FM, HEIMDAL FM, SANDNES FM, SOGNEFJORD FM, TARBERT FM, BRENT GP. See also NPD bulletins.BRENT GP Kelly bushing elevation [m]Elevation of the rotary kelly bushing (RKB) above mean sea level.23.0 Water depth [m]Depth in metres betweem mean sea level and sea floor.372.0 Total depth (MD) [m RKB]Total measured length of wellbore from kelly bushing to total depth (driller's depth).4025.0 Final vertical depth (TVD) [m RKB]Vertical elevation from total depth to kelly bushing. Shown only for released wells. Referred to as true vertical depth (TVD).4024.0 Maximum inclination [°]Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.3.2 Bottom hole temperature [°C]Estimated temperature at final total depth of the wellbore. Shown only for released wells. See discription.153 Oldest penetrated ageAge (according to Geologic Time Scale 2004 by F. M. Gradstein, et al. (2004)) of the oldest penetrated formation. May differ from age at TD for example in deviated wellbores. Examples of legal values: CRETACEOUS, EARLY CRETACEOUS, LATE JURASSIC, EARLY PERMIAN, EARLY TRIASSIC, EOCENE.EARLY JURASSIC Oldest penetrated formationName of the oldest lithostratigraphic unit penetrated by the wellbore. Shown only for released wells. In most wellbores this is formation or group at total depth. May differ from formation or group at TD for example in wellbores drilled with high deviation or through faults. Examples of legal values: AMUNDSEN FM, BALDER FM, BASEMENT, BLODØKS FM, BRYNE FM, BURTON FM, COOK FM, DRAKE FM, DRAUPNE FM, EKOFISK FM, DUNLIN GP.STATFJORD GP Geodetic datumReference system for coordinates. Example of legal values: ED50.ED50 NS degreesGeographic coordinate of the wellhead, north-south degrees.61° 10' 26.42'' N EW degreesGeographic coordinate of the wellhead, east-west degrees.3° 27' 31.36'' E NS UTM [m]Universal Transverse Mercator coordinate of the wellhead, north-south.6782416.83 EW UTM [m]Universal Transverse Mercator coordinate of the wellhead, east-west.524675.04 UTM zoneUniversal Transverse Mercator zone. Examples of legal values: 31, 32, 33, 34.31 NPDID wellboreNPD's unique id for the wellbore.893
Wellbore historyGeneralBlock 35/11 is situated at the boundary between the Horda Platform and the Viking Graben just north of the Troll Field and south of block 35/8 where two gas/condensate discoveries had been made. The work obligation for Block 35/11 included three exploration wells to be drilled to 4000 metres or to Triassic sediments, one of which must test an Early Cretaceous stratigraphic play. The first of these wells, 35/11-1, was drilled in 1984 to a depth of 3361 m in rocks of Triassic age. The primary objective of that well was to assess the hydrocarbon potential of the Middle to Upper Jurassic sands in the "A" structure. No hydrocarbons were present in any of the objectives although good quality Brent sands were encountered. The second well to be drilled on the block was 35/11-2. It was designed primarily to test an Early Cretaceous stratigraphic play, interpreted seismically as a fan development with a 130 km3 closure, and reservoir thickness of 270 m. A secondary objective was the "B" structure at Brent level.Operations and resultsWildcat well 35/11-2 was spudded with the semi-submersible rig Treasure Scout on 20 July 1987 and drilled to TD at 4025 m in Early Jurassic rocks. The hole was drilled to setting depth for 20" casing without a riser. MWD was used, but the resistivity unit was destroyed after few meters. Conventional logs did not get past 760 m, and while attempting this; there was an intrusion of formation fluid into the hole. There was no sign of shallow gas, and heavier mud was used. The hole was opened to 26" without logging below 760 m. The reason for the problems around 760 m was probably washed-out zones. When preparing the setting of 20"casing, fluid was again flowing into the hole, and the mud weight was increased. Further drilling went without significant problems. The well was drilled with spud mud down to 1026 m, with seawater and lignosulphonate from 1026 m to 2195 m, and with a seawater/low solids polymer from 2195 m to TD.The well penetrated the Early Cretaceous at 2682 m (prognosed at 2713 m) and intersected a 225 m thick, predominantly argillaceous/marly sequence. No reservoir rocks were penetrated. At 3011 m Intra Heather Formation sandstone was encountered, and at 3370 m the Brent Group was penetrated (prognosed at 3298 m). The Brent section was 231 m thick with reservoir quality sandstones in the Tarbert, Ness, Etive, and Oseberg Formations. It contained a 175 m gross hydrocarbon column, but the net/gross ratio is low. The logs and RFT pressure data showed a gas/water contact around 3545 m (3522 m SS) in the Oseberg Formation. Oil shows were observed in the Late Jurassic Intra Heather sandstone and throughout the Middle Jurassic Brent Group sandstones. Patchy shows persisted through the Dunlin Group and the Statfjord Formation to total depth. Organic geochemical analyses showed good source rock potential in the Draupne and the Heather Formations, the first of these being the best and more oil prone. The penetrated source intervals were immature to marginally mature, and certainly less mature than the sampled petroleum. Analysis of the DST oils indicated a common source, and the oils increased in maturity with depth.Eight cores were cut in the Late and Middle Jurassic reservoirs (total 129 m). Core recovery was 124.9 m (97%). Four RFT fluid samples were taken. Sample RFT 1 taken at 3040.99 m in the Intra Heather Formation sandstone filled very slowly and recovered gas and mud filtrate with a light oil film. Sample RFT 2 at 3077 m in the Tarbert Formation recovered gas and mud filtrate. Sample RFT 3 at 3481.05 m in the Etive Formation recovered gas and condensate. Sample RFT 4 at3524.98 m in the Oseberg Formation recovered gas and condensate.The well was plugged and abandoned on 4 December 1987 as a gas and condensate discovery.TestingFive drill stem tests, including one in the water leg, were undertaken. The Intra Heather sandstone was tight, with a low net/gross, and was not tested.DST 1, the water test in the lower Oseberg Formation, produced 315 m3 water/day through a 28/64? choke in the main flow. The reservoir temperature was 136 °C.DST 2B in the upper Oseberg Formation produced at maximum 280 Sm3 condensate and 369000 gas /day through a 48/64? choke. The GOR was 1319 Sm3/Sm3. The reservoir temperature was 133.3 °C.DST 3 in the Etive Formation produced at maximum 510 Sm3 condensate and 531000 gas /day through a 40/64? choke. The GOR was 1041Sm3/Sm3. The reservoir temperature was 133.3 °C.DST 4 in the Ness Formation produced at maximum 425 Sm3 condensate and 402400 Sm3 gas /day through a 44/64? choke. The GOR was 946 Sm3/Sm3. The reservoir temperature was 135 °C.DST 5 in the Tarbert Formation produced 415 Sm3 condensate and 177400 Sm3 gas /day through a 32/64? choke in the main flow. The GOR was 427 Sm3/Sm3. The reservoir temperature was 130 °C. This test indicated that there is a thin Tarbert Formation on the top without connection to the rest of the reservoir because the GOR is less than half of the GOR in the other tests.
Cuttings at the NPD
Cuttings at the NPDCuttings available for sampling?NO Cuttings at the NPDCutting sample, top depth [m]Cutting samples, bottom depth [m]1030.004025.00
Cores at the NPD
Cores at the NPDCore sample numberCore sample - top depthCore sample - bottom depthCore sample depth - uom10.023042.03045.2[m ]33369.03391.6[m ]43392.93413.7[m ]53414.03428.9[m ]63452.03462.5[m ]73463.03489.3[m ]83490.03516.3[m ] Cores at the NPDTotal core sample length [m]124.4 Cores at the NPDCores available for sampling?YES
Palynological slides at the NPD
Palynological slides at the NPDSample depthDepth unitSample typeLaboratory2745.0[m]DCRRI2772.0[m]DCRRI2808.0[m]DCRRI2835.0[m]DCRRI2865.0[m]DCRRI2950.0[m]DCRRI2970.0[m]DCRRI2991.0[m]DCRRI3033.0[m]DCRRI3042.3[m]CRRI3042.9[m]CRRI3044.2[m]CRRI3044.8[m]CRRI3045.2[m]CRRI3135.0[m]DCRRI3371.4[m]CGEOSTRAT3375.0[m]CRRI3376.6[m]CGEOSTRAT3382.3[m]CGEOSTR3383.0[m]CRRI3393.5[m]CGEOSTRAT3397.0[m]CRRI3400.2[m]CGEOSTRAT3411.6[m]CGEOSTR3412.0[m]CRRI3421.7[m]CRRI3422.0[m]CRRI3456.8[m]CGEOSTRAT3462.1[m]CGEOSTR3462.3[m]CRRI3468.7[m]CGEOSTRAT3474.0[m]CRRI3478.9[m]CGEOSTR3480.2[m]CRRI3492.9[m]CGEOSTRAT3505.3[m]CGEOSTR3511.0[m]CRRI3515.8[m]CGEOSTRAT3612.0[m]DCRRI3630.0[m]DCRRI3648.0[m]DCRRI3672.0[m]DCRRI3690.0[m]DCRRI3762.0[m]DCRRI3822.0[m]DCRRI3846.0[m]DCRRI3870.0[m]DCRRI3900.0[m]DCRRI3942.0[m]DCRRI3960.0[m]DCRRI3978.0[m]DCRRI
Oil samples at the NPD
Oil samples at the NPDTest typeBottle numberTop depth
MD [m]Bottom depth
MD [m]Fluid typeTest timeSamples availableDSTDST23524.003542.0003.11.1987 - 00:00YESDST3524.003542.0009.11.1987 - 00:00YESDSTDST2B0.000.0009.11.1987 - 00:00YESDSTDST33477.003486.5012.11.1987 - 00:00YESDSTDST43370.003378.0014.11.1987 - 00:00YESDSTDST40.000.0014.11.1987 - 02:00YESDSTDST43427.003432.0014.11.1987 - 00:00YESDST3374.003378.0019.11.1987 - 00:00YESDSTDST 53378.003374.0019.11.1987 - 00:00YESDSTDST5A3374.003378.00YES
LithostratigraphyTop depth [m]Lithostrat. unit3957418241081166316631721175319261950195020872675268226822710272129272927301130423370337033803475348735243601360136153712373037753798
Composite logsDocument nameDocument formatDocument size [MB]0.73
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]46.01
Drill stem tests (DST)
Drill stem tests (DST)Test numberFrom depth MD
[m]To depth MD
Drill stem tests (DST)Test numberFinal shut-in pressure
[MPa]Final flow pressure
[MPa]Bottom hole pressure
Drill stem tests (DST)Test numberOil
[g/cm3]Gas grav. rel.airGOR
LogsLog typeLog top depth [m]Log bottom depth [m]CBL VDL GR8572184CBL VDL GR21633348CBL VDL GR33563972CET GR32623596CST00DIL BHC GR547759DIL BHC GR10022188DIL LSS GR390759DIL LSS GR21853372DIL SDT GR33504028DLL MSFL GR21853372DLL MSFL GR33504026LDL CNL GR7252188LDL CNL GR21853373LDL CNL NGS33504030MWD - GR RES DIR3724025MWD - GR RLL33783517NGS33504030RFT29453042RFT29953373RFT33773963SHDT21853373SHDT33504029VELOCITY14304030
Casing and leak–off tests
Casing and leak–off testsCasing typeCasing diam.
[m]LOT/FIT mud eqv.
[g/cm3]Formation test typeCONDUCTOR30546.8361026.00.00LOTSURF.COND.201004.0261026.01.39LOTINTERM.13 3/82184.617 1/22195.01.62LOTINTERM.9 3/53348.812 1/43377.01.85LOTLINER74025.08 1/24025.00.00LOT
Drilling mudDepth MD [m]Mud weight [g/cm3]Visc. [mPa.s]Yield point [Pa]Mud typeDate measured11.03WATER BASED23.07.19874611.02WATER BASED22.07.19875501.03WATER BASED23.07.19875501.06WATER BASED27.07.19875561.06WATER BASED27.07.19876491.006.003WATER BASED28.07.198710261.06OIL BASED29.07.198710261.06WATER BASED03.08.198710261.30WATER BASED03.08.198710261.32WATER BASED03.08.198711801.2610.014.4WATER BASED10.08.198713351.2616.027.8WATER BASED10.08.198713351.2616.027.8WATER BASED11.08.198713501.3011.028.3WATER BASED13.08.198713501.2616.023.0WATER BASED11.08.198713501.2614.015.4WATER BASED11.08.198713501.2612.031.1WATER BASED12.08.198713501.3013.029.7WATER BASED18.08.198713501.3013.026.8WATER BASED18.08.198713501.3018.023.5WATER BASED19.08.198713501.3012.034.5WATER BASED14.08.198713501.3013.029.2WATER BASED18.08.198721951.2026.08.6WATER BASED20.08.198723101.2018.08.6WATER BASED21.08.198723431.2023.07.7WATER BASED24.08.198724421.2025.08.1WATER BASED24.08.198725441.2026.08.6WATER BASED24.08.198725591.2232.09.1WATER BASED25.08.198726311.2425.010.5WATER BASED26.08.198726851.2027.09.6WATER BASED27.08.198727381.2027.09.6WATER BASED28.08.198727881.2031.011.0WATER BASED31.08.198728861.2028.012.5WATER BASED31.08.198729341.2024.012.5WATER BASED31.08.198729501.2225.012.0WATER BASED03.09.198729501.2225.011.0WATER BASED03.09.198729501.2233.012.5WATER BASED04.09.198729501.2225.012.0WATER BASED07.09.198729501.2223.011.0WATER BASED07.09.198729501.2223.012.0WATER BASED07.09.198733771.4328.011.0WATER BASED09.09.198733771.5125.08.6WATER BASED09.09.198733771.5430.011.0WATER BASED10.09.198733771.5729.010.0WATER BASED11.09.198733771.5729.012.0WATER BASED14.09.198733771.5728.010.5WATER BASED14.09.198733771.5729.09.1WATER BASED16.09.198733771.6243.01.1WATER BASED18.09.198733771.5733.014.4WATER BASED14.09.198733771.5823.06.7WATER BASED07.10.198733771.5815.06.2WATER BASED08.10.198733771.5816.04.8WATER BASED09.10.198733791.6233.08.6WATER BASED21.09.198733981.6227.07.2WATER BASED21.09.198734171.6228.06.7WATER BASED21.09.198734381.6222.06.7WATER BASED21.09.198734611.6231.08.1WATER BASED22.09.198734881.6230.08.1WATER BASED23.09.198735041.6230.07.7WATER BASED24.09.198735211.6225.07.7WATER BASED25.09.198735801.6225.09.1WATER BASED28.09.198736821.6225.09.6WATER BASED28.09.198737191.6222.07.7WATER BASED28.09.198737741.6224.09.6WATER BASED29.09.198737871.6218.08.1WATER BASED01.10.198738351.6222.09.6WATER BASED30.09.198739611.6220.06.2WATER BASED05.10.198739621.5825.07.7WATER BASED06.10.198740251.6215.04.8WATER BASED05.10.198740251.6215.44.8WATER BASED05.10.198740251.5820.06.7WATER BASED05.10.1987
Thin sections at the NPD
Thin sections at the NPDDepthUnit3043.36[m ]
Pressure plotsThe 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 plotsDocument nameDocument formatDocument size [MB]0.23