General information Attribute Value Wellbore nameOfficial name of wellbore based on NPD guidelines for designation of wells and wellbores.25/7-2 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 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.25/7-2 Seismic locationPosition of spud location on seismic survey lines. SP: shotpoint.CN 8525 - 6 SP 390 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.Conoco 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.628-L Drilling facilityNPD's name of the facility which the wellbore was drilled from. Drilling daysNumber of days from wellbore entry to wellbore completion.161 Entered dateThe date when he wellbore was spudded. For sidetracks: The date when new formation was drilled by kicking off from the mother-wellbore,08.02.1990 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.18.07.1992 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.17.12.2003 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.LATE 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.INTRA DRAUPNE FM SS 2nd level with HC, ageAge of lithostratigraphic unit, 2nd level, where hydrocarbons were encountered. Examples of legal values: CRETACEOUS, EARLY CRETACEOUS, LATE JURASSIC, EOCENE.MIDDLE JURASSIC 2nd level with HC, formationName of lithostartigraphic unit, 2nd 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.HUGIN FM Kelly bushing elevation [m]Elevation of the rotary kelly bushing (RKB) above mean sea level.25.0 Water depth [m]Depth in metres betweem mean sea level and sea floor.124.0 Total depth (MD) [m RKB]Total measured length of wellbore from kelly bushing to total depth (driller's depth).4850.0 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).4847.0 Maximum inclination [°]Maximum deviation, in degrees, from a vertical well path.Shown only for released wells.12.9 Bottom hole temperature [°C]Estimated temperature at final total depth of the wellbore. Shown only for released wells. See discription.163 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.MIDDLE 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.SLEIPNER FM Geodetic datumReference system for coordinates. Example of legal values: ED50.ED50 NS degreesGeographic coordinate of the wellhead, north-south degrees.59° 16' 28.59'' N EW degreesGeographic coordinate of the wellhead, east-west degrees.2° 12' 26.09'' E NS UTM [m]Universal Transverse Mercator coordinate of the wellhead, north-south.6571051.25 EW UTM [m]Universal Transverse Mercator coordinate of the wellhead, east-west.454816.14 UTM zoneUniversal Transverse Mercator zone. Examples of legal values: 31, 32, 33, 34.31 NPDID wellboreNPD's unique id for the wellbore.1494
Wellbore historyGeneralNorwegian Continental Shelf Block 25/7 is located west of the Utsira basement High on the eastern flank of the Southern Viking Graben. The location is 5.3 km southwest of 25/7-1 which drilled into basement after the Cretaceous section without penetrating any Jurassic sediments and thus failed to test its target, Late Jurassic sandstones. With the 25/7-2 location further to the west one expected to penetrate a complete Brae analogue sequence. The main objectives of the well were to test the hydrocarbon potential of the Late Jurassic sands, the hydrocarbon potential of a structural closure at the Middle Jurassic sand level, and the hydrocarbon bearing potential of the Paleocene Heimdal sands. Trapping at Late and Middle Jurassic was assumed by sealing basement rocks to the east, and by dip closure elsewhere. Events interpreted as possible gas bearing sands occur between 200 and 300 m below sea level.Operations and resultsWildcat well 25/7-2 was spudded 8 February 1990by the semi-submersible rig Dyvi Stena, and completed 18 July 1990 at a depth of 4850 m in the Middle Jurassic Sleipner Formation. The well was drilled with Seawater and hi-vis pills down to 1220 m and with KCl Polymer WBS/200 mud from 1220 m to TD. Drilling took 131 days from spud and 142 days from taking over the rig. A further 29 days were used to log, test, and plug and abandon the well. The rig was on contract for a total of 171 days. One hundred and thirty days were used for planned operations while wait-on-weather, fishing operations, and equipment trouble accounted for the NPT. No indications of shallow gas were observed.Forty-seven metres of Cenomanian sand was encountered in the well. A gross thickness of 174 meters of hydrocarbon bearing Late Jurassic conglomerates and sandstones were encountered in the well. The Late Jurassic conglomerates and sandstones represent deposition by debris-flows, slumps and slides and minor turbidites on a fault-scarp submarine slope apron. The sequence had poor reservoir properties in the 25/7-2 location. Sedimentological interpretation and modelling as well as the DST analysis have shown the reservoir to be of limited size. It was therefore concluded that the 25/7-2 well encountered the Upper Jurassic conglomerate/sandstone sequence in a non-producible reservoir facies. The Middle Jurassic Hugin formation was 206 meters thick and was composed of sands deposited in an overall transgressive coastal barrier system. Hydrocarbons were present down to the base of the sands; however, the reservoir quality was extremely poor. The sandstones were intensely cemented and contained large amounts of fibrous illite. The Middle Jurassic Sleipner Formation had a very low sand/shale ratio. The FMS evaluation showed the sandstones to be intensely cemented. No net sand was interpreted from the log analysis.A total of 210 sidewall cores were attempted and 91 were recovered. Four conventional cores were cut in the interval from 4125 to 4169.2 m, and two in the interval from 4345 to 4488 m. No fluid samples were taken on wire line. The well was permanently plugged and abandoned on 18 July 1990 as gas and condensate discovery.TestingA single drill stem test was conducted over the hydrocarbon-bearing interval of the Late Jurassic Intra Draupne and Intra Heather -Formation Sandstone. The perforated intervals were 4148 m to 4173 m, 4194 m to 4219 m, and 4248 m to 4273 m. Contribution to flow was from the Intra Draupne Formation Sandstone in the upper set of perforations (4148 ? 4173 m). Initial flow rates through a 40/64" choke were 255700 Sm3 gas, 228 Sm3 condensate, and 2.7 Sm3 water pr day through a 15.9 mm choke. Initial GOR was 1121 Sm3/ Sm3. Pressure and flow rates declined while GOR increased during the test. Separator condensate density was 0.784 g/cm3 (at 15°C) while separator gas gravity was 0.710 (air = 1). From PVT analyses the stock tank oil density was found to be 0.775 g/cm3 and the stock tank gas gravity 0.756 (air = 1).
Cuttings at the NPD
Cuttings at the NPDCuttings available for sampling?YES Cuttings at the NPDCutting sample, top depth [m]Cutting samples, bottom depth [m]1230.004850.00
Cores at the NPD
Cores at the NPDCore sample numberCore sample - top depthCore sample - bottom depthCore sample depth - uom14125.04136.3[m ]24136.24145.7[m ]34145.74154.6[m ]44154.74169.2[m ]54345.04347.4[m ]64461.54488.6[m ] Cores at the NPDTotal core sample length [m]73.8 Cores at the NPDCores available for sampling?YES
Palynological slides at the NPD
Palynological slides at the NPDSample depthDepth unitSample typeLaboratory4109.0[m]DCRRI4115.0[m]DCRRI4125.1[m]CRRI4127.4[m]CRRI4162.6[m]CRRI4163.3[m]CRRI4164.4[m]CRRI4226.0[m]CRRI4245.0[m]CRRI4265.0[m]CRRI
Oil samples at the NPD
Oil samples at the NPDTest typeBottle numberTop depth
MD [m]Bottom depth
MD [m]Fluid typeTest timeSamples availableDST4148.004273.0011.07.1990 - 00:00YES
LithostratigraphyTop depth [m]Lithostrat. unit14944665168768710032098209821852216222222582318247025292698269827492925306032603295339934473714371438753948405640564119421242474293440744074613
Composite logsDocument nameDocument formatDocument size [MB]0.71
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]34.48
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]CST12252691CST39524121CST41764310CST43004340CST43654839DIL GR SLS SP AMS39114851DIL LSS MSFL GR SP AMS12102963DIL SLS GR SP AMS39114344DLL MSFL GR SP40504849DLL MSFL NGS CAL SP39114012DLL MSFL NGS CAL SP39114340FMS GR40104852LDL CNL GR CAL39114345LDL CNL NGL CAL40504852LDL DIL LSS GR CAL SP AMS2591925LDL DIL SLS MSFL GR CAL AMS29693918LDL GR CAL12102964MWD DPR39144345MWD RGD2651030MWD RGD35893914MWD RGD43494850MWD RGD-M10303440RFT41384292RFT42554567
Casing and leak–off tests
Casing and leak–off testsCasing typeCasing diam.
[m]LOT/FIT mud eqv.
[g/cm3]Formation test typeCONDUCTOR30259.036265.00.00LOTINTERM.201210.5261220.01.57LOTINTERM.13 3/82965.017 1/22974.01.94LOTINTERM.9 5/83906.012 1/43914.01.96LOTLINER74850.08 1/24850.00.00LOT
Drilling mudDepth MD [m]Mud weight [g/cm3]Visc. [mPa.s]Yield point [Pa]Mud typeDate measured1951.9226.012.0WATER BASED17.07.19901951.9222.011.0WATER BASED17.07.19902651.07WATER BASED12.02.19902651.06WATER BASED09.02.19903421.07WATER BASED12.02.199010301.07WATER BASED12.02.199010301.08WATER BASED13.02.199010501.08WATER BASED14.02.199010501.08WATER BASED15.02.199012181.08WATER BASED16.02.199012201.08WATER BASED19.02.199012201.2017.020.0WATER BASED20.02.199012201.2017.011.5WATER BASED21.02.199012201.0219.011.5WATER BASED23.02.199012201.2018.010.5WATER BASED26.02.199012201.2019.011.5WATER BASED26.02.199012201.2019.011.0WATER BASED27.02.199012201.2019.010.5WATER BASED28.02.199012201.2018.012.0WATER BASED22.02.199012201.2018.011.5WATER BASED26.02.199012501.2016.010.0WATER BASED01.03.199014761.2515.09.5WATER BASED02.03.199016841.2919.09.0WATER BASED06.03.199019381.3521.09.5WATER BASED06.03.199019381.3921.09.5WATER BASED06.03.199019381.3921.09.5WATER BASED06.03.199019401.4122.09.5WATER BASED07.03.199019401.4121.08.5WATER BASED08.03.199019581.4124.08.0WATER BASED09.03.199020051.4127.09.0WATER BASED12.03.199021131.2529.013.5WATER BASED12.03.199021301.4129.011.0WATER BASED12.03.199021781.4127.09.5WATER BASED13.03.199023151.2532.011.0WATER BASED14.03.199024371.4030.011.5WATER BASED16.03.199024401.4031.011.0WATER BASED16.03.199025041.4039.012.0WATER BASED20.03.199025451.4029.012.5WATER BASED20.03.199025451.4029.011.0WATER BASED20.03.199025661.4027.013.0WATER BASED20.03.199026301.4027.013.0WATER BASED21.03.199026951.4033.011.0WATER BASED22.03.199027071.4026.09.0WATER BASED23.03.199027071.4027.09.0WATER BASED26.03.199027071.4026.09.0WATER BASED26.03.199027071.4022.010.0WATER BASED26.03.199027371.4030.011.5WATER BASED27.03.199027471.4035.012.5WATER BASED28.03.199027471.4030.011.0WATER BASED29.03.199027471.4029.011.0WATER BASED30.03.199027471.4028.011.0WATER BASED02.04.199027471.4027.010.5WATER BASED02.04.199028111.4023.011.5WATER BASED02.04.199028431.4027.011.5WATER BASED05.04.199028431.4022.010.0WATER BASED04.04.199028641.4129.010.0WATER BASED06.04.199028951.4028.010.5WATER BASED09.04.199029241.4032.012.0WATER BASED10.04.199029581.4027.012.0WATER BASED10.04.199029741.4027.010.5WATER BASED11.04.199029741.4028.011.0WATER BASED18.04.199029741.4026.010.0WATER BASED18.04.199029741.4022.09.0WATER BASED18.04.199029741.3416.02.5WATER BASED18.04.199029741.4021.08.5WATER BASED18.04.199029741.4028.011.0WATER BASED10.04.199029741.4026.010.0WATER BASED18.04.199030341.3422.07.5WATER BASED18.04.199031351.3421.08.5WATER BASED19.04.199032501.3423.012.0WATER BASED23.04.199033491.3425.012.5WATER BASED23.04.199034221.4426.013.0WATER BASED23.04.199034401.4426.012.0WATER BASED24.04.199034451.4426.012.0WATER BASED25.04.199035061.4419.09.0WATER BASED26.04.199035611.4721.010.0WATER BASED27.04.199035891.4722.010.0WATER BASED30.04.199036421.5124.011.5WATER BASED30.04.199037131.9220.05.0WATER BASED16.07.199039121.6521.06.5WATER BASED03.05.199039141.6516.06.0WATER BASED08.05.199039141.6516.05.5WATER BASED08.05.199039141.6520.05.5WATER BASED04.05.199039201.6817.04.5WATER BASED08.05.199039691.7618.05.5WATER BASED08.05.199040311.8721.06.0WATER BASED09.05.199040791.9221.07.0WATER BASED10.05.199041201.9218.07.5WATER BASED11.05.199041251.9219.09.5WATER BASED15.05.199041311.9217.08.0WATER BASED15.05.199041361.9218.05.5WATER BASED15.05.199041461.9217.05.0WATER BASED15.05.199041551.9216.04.5WATER BASED16.05.199041691.9218.05.5WATER BASED18.05.199041951.9217.06.0WATER BASED21.05.199042401.9215.07.0WATER BASED21.05.199043021.9416.08.0WATER BASED21.05.199043421.9814.07.5WATER BASED22.05.199043451.9515.07.0WATER BASED23.05.199043451.9214.07.0WATER BASED25.05.199043451.9214.07.5WATER BASED29.05.199043451.9214.07.0WATER BASED29.05.199043451.9214.07.5WATER BASED29.05.199043451.9213.06.0WATER BASED30.05.199043451.9213.011.0WATER BASED01.06.199043451.9215.09.0WATER BASED06.06.199043451.9214.09.0WATER BASED06.06.199043451.9814.08.0WATER BASED22.05.199043451.9214.07.5WATER BASED25.05.199043451.9214.04.5WATER BASED31.05.199043451.9214.09.0WATER BASED05.06.199043491.9215.010.0WATER BASED06.06.199043491.9215.010.0WATER BASED07.06.199043491.9214.010.0WATER BASED08.06.199043981.9218.014.0WATER BASED08.06.199044621.9217.012.0WATER BASED08.06.199044891.9216.013.0WATER BASED12.06.199044951.9216.011.0WATER BASED12.06.199045201.9216.010.0WATER BASED12.06.199046241.9217.012.0WATER BASED12.06.199046431.9217.015.0WATER BASED13.06.199047271.9217.07.5WATER BASED14.06.199047391.9210.011.0WATER BASED15.06.199047691.9215.05.0WATER BASED19.06.199048021.9214.06.0WATER BASED19.06.199048091.9216.08.5WATER BASED19.06.199048121.9212.05.0WATER BASED05.07.199048121.9312.05.0WATER BASED09.07.199048121.9213.05.0WATER BASED10.07.199048121.9210.05.0WATER BASED10.07.199048121.9211.06.0WATER BASED02.07.199048121.9211.05.5WATER BASED02.07.199048121.9212.05.5WATER BASED03.07.199048121.9212.05.0WATER BASED10.07.199048121.9212.07.0WATER BASED16.07.199048301.9214.07.5WATER BASED19.06.199048501.9214.07.0WATER BASED20.06.199048501.9214.07.5WATER BASED21.06.199048501.9213.07.5WATER BASED25.06.199048501.9212.07.5WATER BASED25.06.199048501.9213.06.5WATER BASED27.06.199048501.9214.05.5WATER BASED28.06.199048501.9212.05.5WATER BASED04.07.199048501.9210.05.0WATER BASED10.07.199048501.928.014.0WATER BASED11.07.199048501.9212.07.5WATER BASED12.07.199048501.9220.07.0WATER BASED02.07.199048501.9213.06.5WATER BASED02.07.199048501.9212.07.5WATER BASED13.07.199048501.9215.06.5WATER BASED22.06.199048501.9212.08.0WATER BASED25.06.199048501.9212.05.5WATER BASED26.06.1990
Thin sections at the NPD
Thin sections at the NPDDepthUnit4131.00[m ]4146.25[m ]4148.25[m ]4152.75[m ]4160.25[m ]4166.00[m ]4168.00[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]0.22